Sample records for temporal flow variations

  1. Temporal variations of the rotation rate in the solar interior

    E-Print Network [OSTI]

    H. M. Antia; Sarbani Basu

    2000-04-25T23:59:59.000Z

    The temporal variations of the rotation rate in the solar interior are studied using frequency splittings from Global Oscillations Network Group (GONG) data obtained during the period 1995-99. We find alternating latitudinal bands of faster and slower rotation which appear to move towards the equator with time - similar to the torsional oscillations seen at the solar surface. This flow pattern appears to persist to a depth of about 0.1R_sun and in this region its magnitude is well correlated with solar activity indices. We do not find any periodic or systematic changes in the rotation rate near the base of the convection zone.

  2. TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES...

    Open Energy Info (EERE)

    OF SHEAR-WAVE SPLITTING Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE...

  3. Temporal Geochemical Variations In Volatile Emissions From Mount...

    Open Energy Info (EERE)

    Geochemical Variations In Volatile Emissions From Mount St Helens, Usa, 1980-1994 Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Temporal...

  4. Solar cycle variations of large scale flows in the Sun

    E-Print Network [OSTI]

    Sarbani Basu; H. M. Antia

    2000-01-17T23:59:59.000Z

    Using data from the Michelson Doppler Imager (MDI) instrument on board the Solar and Heliospheric Observatory (SOHO), we study the large-scale velocity fields in the outer part of the solar convection zone using the ring diagram technique. We use observations from four different times to study possible temporal variations in flow velocity. We find definite changes in both the zonal and meridional components of the flows. The amplitude of the zonal flow appears to increase with solar activity and the flow pattern also shifts towards lower latitude with time.

  5. Temporal Variations in the Sun's Rotational Kinetic Energy

    E-Print Network [OSTI]

    H. M. Antia; S. M. Chitre; D. O. Gough

    2007-11-06T23:59:59.000Z

    AIM: To study the variation of the angular momentum and the rotational kinetic energy of the Sun, and associated variations in the gravitational multipole moments, on a timescale of the solar cycle. METHOD: Inverting helioseismic rotational splitting data obtained by the Global Oscillation Network Group and by the Michelson Doppler Imager on the Solar and Heliospheric Observatory. RESULTS: The temporal variation in angular momentum and kinetic energy at high latitudes (>\\pi/4) through the convection zone is positively correlated with solar activity, whereas at low latitudes it is anticorrelated, except for the top 10% by radius where both are correlated positively. CONCLUSION: The helioseismic data imply significant temporal variation in the angular momentum and the rotational kinetic energy, and in the gravitational multipole moments. The properties of that variation will help constrain dynamical theories of the solar cycle.

  6. REVISITING THE SOLAR TACHOCLINE: AVERAGE PROPERTIES AND TEMPORAL VARIATIONS

    SciTech Connect (OSTI)

    Antia, H. M. [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Basu, Sarbani, E-mail: antia@tifr.res.in, E-mail: sarbani.basu@yale.edu [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)

    2011-07-10T23:59:59.000Z

    The tachocline is believed to be the region where the solar dynamo operates. With over a solar cycle's worth of data available from the Michelson Doppler Imager and Global Oscillation Network Group instruments, we are in a position to investigate not merely the average structure of the solar tachocline, but also its time variations. We determine the properties of the tachocline as a function of time by fitting a two-dimensional model that takes latitudinal variations of the tachocline properties into account. We confirm that if we consider the central position of the tachocline, it is prolate. Our results show that the tachocline is thicker at latitudes higher than the equator, making the overall shape of the tachocline more complex. Of the tachocline properties examined, the transition of the rotation rate across the tachocline, and to some extent the position of the tachocline, show some temporal variations.

  7. Temporal variations of solar rotation rate at high latitudes

    E-Print Network [OSTI]

    H. M. Antia; Sarbani Basu

    2001-08-14T23:59:59.000Z

    Frequency splitting coefficients from Global Oscillation Network Group (GONG) and Michelson Doppler Imager (MDI) observations covering the period 1995--2001 are used to study temporal variations in the solar rotation rate at high latitudes. The torsional oscillation pattern in the Sun is known to penetrate to a depth of about $0.1R_\\odot$ with alternate bands of faster and slower rotating plasma. At lower latitudes the bands move towards equator with time. At higher latitudes, however, the bands appear to move towards the poles. This is similar to the observed pole-ward movement of large scale magnetic fields at high latitudes. This also supports theoretical results of pole-ward moving bands at high latitudes in some mean field dynamo models. The polar rotation rate is found to decrease between 1995 and 1999 after which it has started increasing.

  8. Study of temporal variation of radon concentrations in public drinking water supplies

    SciTech Connect (OSTI)

    York, E.L. [Univ. of North Carolina, Chapel Hill, NC (United States). Dept. of Environmental Sciences and Engineering

    1995-12-31T23:59:59.000Z

    The Environmental Protection Agency (EPA) has proposed a Maximum Contaminant Level (MCL) for radon-222 in public drinking water supplies of 300 pCi/L. Proposed monitoring requirements include collecting quarterly grab samples for the first year, then annual samples for the remainder of the compliance cycle provided first year quarterly samples average below the MCL. The focus of this research was to study the temporal variation of groundwater radon concentrations to investigate how reliably one can predict an annual average radon concentration based on the results of grab samples. Using a {open_quotes}slow-flow{close_quotes} collection method and liquid scintillation analysis, biweekly water samples were taken from ten public water supply wells in North Carolina (6 month - 11 month sampling periods). Based on study results, temporal variations exist in groundwater radon concentrations. Statistical analysis performed on the data indicates that grab samples taken from each of the ten wells during the study period would exhibit groundwater radon concentrations within 30% of their average radon concentration.

  9. Supplementary Information for Methanol as a sensitive probe for spatial and temporal variations of the

    E-Print Network [OSTI]

    Supplementary Information for Methanol as a sensitive probe for spatial and temporal variations.757 0.68(5) Table I. Methanol (12 CH16 3 OH) maser transitions and accurate rest frequencies taken from

  10. An integrated experimental and numerical study: Developing a reaction transport model that couples chemical reactions of mineral dissolution/precipitation with spatial and temporal flow variations in CO2/brine/rock systems

    Broader source: Energy.gov [DOE]

    Project objectives: Generate and characterize mineral dissolution/precipitation reactions in supercritical CO2/brine/rock systems under pressure-temperature-chemistry conditions resembling CO2injection into EGS. Characterize three-dimensional spatial and temporal distributions of rock structures subject to mineral dissolution/precipitation processes by X-ray tomography, SEM imaging, and Microprobe analysis.

  11. A study of possible temporal and latitudinal variations in the properties of the solar tachocline

    E-Print Network [OSTI]

    Sarbani Basu; H. M. Antia

    2001-01-18T23:59:59.000Z

    Temporal variations of the structure and the rotation rate of the solar tachocline region are studied using helioseismic data from the Global Oscillation Network Group (GONG) and the Michelson Doppler Imager (MDI) obtained during the period 1995--2000. We do not find any significant temporal variation in the depth of the convection zone, the position of the tachocline or the extent of overshoot below the convection zone. No systematic variation in any other properties of the tachocline, like width, etc., is found either. Possibility of periodic variations in these properties is also investigated. Time-averaged results show that the tachocline is prolate with a variation by about 0.02R_sun in its position. The depth of the convection zone or the extent of overshoot does not show any significant variation with latitude.

  12. Gradual Variation Analysis for Groundwater Flow

    E-Print Network [OSTI]

    Chen, Li

    2010-01-01T23:59:59.000Z

    Groundwater flow in Washington DC greatly influences the surface water quality in urban areas. The current methods of flow estimation, based on Darcy's Law and the groundwater flow equation, can be described by the diffusion equation (the transient flow) and the Laplace equation (the steady-state flow). The Laplace equation is a simplification of the diffusion equation under the condition that the aquifer has a recharging boundary. The practical way of calculation is to use numerical methods to solve these equations. The most popular system is called MODFLOW, which was developed by USGS. MODFLOW is based on the finite-difference method in rectangular Cartesian coordinates. MODFLOW can be viewed as a "quasi 3D" simulation since it only deals with the vertical average (no z-direction derivative). Flow calculations between the 2D horizontal layers use the concept of leakage. In this project, we have established a mathematical model based on gradually varied functions for groundwater data volume reconstruction. T...

  13. Variational principle for optimal accelerated neutralized flow A. Fruchtman

    E-Print Network [OSTI]

    Variational principle for optimal accelerated neutralized flow A. Fruchtman Holon Academic Institute of Technology, 52 Golomb Street, P.O. Box 305, Holon 58102, Israel N. J. Fisch Princeton Plasma

  14. Temporal and spatial variation in age-specific survival rates of a long-lived mammal,

    E-Print Network [OSTI]

    Aberdeen, University of

    . INTRODUCTION Understanding variability in survival patterns is funda- mental to life-history theory, wildlifeTemporal and spatial variation in age-specific survival rates of a long-lived mammal, the Hawaiian 8YJ, UK Estimates of variability in pinniped survival rates are generally based on observations

  15. Effects of spatial and temporal variations in aerosol properties on mean cloud albedo

    E-Print Network [OSTI]

    in quantifying the effects of cloud on radiation budget and aerosol indirect effects on global scaleEffects of spatial and temporal variations in aerosol properties on mean cloud albedo Jian Wang1 effect on mean cloud albedo, was investigated using data collected at Pt. Reyes, California, during

  16. Temporal integration of focus position signal during compensation for pursuit in optic flow

    E-Print Network [OSTI]

    Krekelberg, Bart

    Temporal integration of focus position signal during compensation for pursuit in optic flow Center in optic flow that specifies heading. Concurrent smooth pursuit causes distortion of the retinal flow on optic flow perception has received little attention. Here we separated the effects of velocity and gaze

  17. Relativistic Hydrodynamic Flows Using Spatial and Temporal Adaptive Structured Mesh Refinement

    E-Print Network [OSTI]

    Peng Wang; Tom Abel; Weiqun Zhang

    2007-12-31T23:59:59.000Z

    Astrophysical relativistic flow problems require high resolution three-dimensional numerical simulations. In this paper, we describe a new parallel three-dimensional code for simulations of special relativistic hydrodynamics (SRHD) using both spatially and temporally structured adaptive mesh refinement (AMR). We used the method of lines to discretize the SRHD equations spatially and a total variation diminishing (TVD) Runge-Kutta scheme for time integration. For spatial reconstruction, we have implemented piecewise linear method (PLM), piecewise parabolic method (PPM), third order convex essentially non-oscillatory (CENO) and third and fifth order weighted essentially non-oscillatory (WENO) schemes. Flux is computed using either direct flux reconstruction or approximate Riemann solvers including HLL, modified Marquina flux, local Lax-Friedrichs flux formulas and HLLC. The AMR part of the code is built on top of the cosmological Eulerian AMR code {\\sl enzo}. We discuss the coupling of the AMR framework with the relativistic solvers. Via various test problems, we emphasize the importance of resolution studies in relativistic flow simulations because extremely high resolution is required especially when shear flows are present in the problem. We also present the results of two 3d simulations of astrophysical jets: AGN jets and GRB jets. Resolution study of those two cases further highlights the need of high resolutions to calculate accurately relativistic flow problems.

  18. Temporal variations in space-time and progenitors of gamma ray burst and millisecond pulsars

    E-Print Network [OSTI]

    Preston Jones

    2007-08-31T23:59:59.000Z

    A time varying space-time metric is shown to be a source of electromagnetic radiation. The post-Newtonian approximation is used as a realistic model of the connection between the space-time metric and a time varying gravitational potential. Large temporal variations in the metric from the coalescence of colliding black holes and neutron stars are shown to be possible progenitors of gamma ray burst and millisecond pulsars.

  19. {sup 222}Rn in water: A comparison of two sample collection methods and two sample transport methods, and the determination of temporal variation in North Carolina ground water

    SciTech Connect (OSTI)

    Hightower, J.H. III [North Carolina Univ., Chapel Hill, NC (United States). Dept. of Environmental Sciences and Engineering] [North Carolina Univ., Chapel Hill, NC (United States). Dept. of Environmental Sciences and Engineering

    1994-12-31T23:59:59.000Z

    Objectives of this field experiment were: (1) determine whether there was a statistically significant difference between the radon concentrations of samples collected by EPA`s standard method, using a syringe, and an alternative, slow-flow method; (2) determine whether there was a statistically significant difference between the measured radon concentrations of samples mailed vs samples not mailed; and (3) determine whether there was a temporal variation of water radon concentration over a 7-month period. The field experiment was conducted at 9 sites, 5 private wells, and 4 public wells, at various locations in North Carolina. Results showed that a syringe is not necessary for sample collection, there was generally no significant radon loss due to mailing samples, and there was statistically significant evidence of temporal variations in water radon concentrations.

  20. Methanol as a Sensitive Probe for Spatial and Temporal Variations of the Proton-to-Electron Mass Ratio

    E-Print Network [OSTI]

    Methanol as a Sensitive Probe for Spatial and Temporal Variations of the Proton-to-Electron Mass, corresponding to the 51 ! 60Aþ and 20 ! 3À1E transitions in methanol (CH3OH), respectively, are among transitions in the ground state of methanol to a variation of the proton-to- electron mass ratio. We show

  1. DDT in Mytilus edulis: Spatio-temporal variations in the Punta Banda estuary, Baja California, Mexico

    SciTech Connect (OSTI)

    Galindo-Bect, M.S.; Flores-Baez, B.P. (Univ. Autonoma de Baja California, Ensenada (Mexico))

    1991-02-01T23:59:59.000Z

    The mussel Mytilus sp. has been widely used as a sentinel organism or biological indicator of organic pollutants in the marine environment. In studies recently carried out in Baja California, Mexico, it was found that the spatial and temporal variations of DDT in samples of the mussel Mytilus californianus collected from the area exposed to the ocean do not follow a defined pattern and that the highest values of DDT are found at the border with the US. The Maneadero Valley in Baja California, Mexico, is an agricultural area where important volumes of pesticides are applied, part of which are transported to the Punta Banda Estuary where they remain for an undetermined period of time during which they are consumed and bioaccumulated by organisms. The main objective of the present work is to determine the levels and temporal variation of DDT in the mussel Mytilus edulis in the Punta Banda Estuary, Baja California. With the results, the authors will define the dynamics of this pollutant in the estuary.

  2. Spatial and Temporal Variations of Light Curves in Gravitationally Lensed Sources

    E-Print Network [OSTI]

    A. A. Minakov; V. G. Vakulik

    2004-01-06T23:59:59.000Z

    Effects of macro-and microlensing on the spatial and temporal characteristics of images of remote sources, observed through the inner regions of lensing galaxies are discussed. A particular attention was given to the case, when microlenses, - stars, star-like or planetary bodies, - are situated near the critical curves of macrolenses, - galaxies, stellar clusters, etc. The investigation is of interest for the gravitational lens (GL) systems, where the lensed images are observed close to the critical curve of a macrolens. Annular, arched or confluent images should be regarded as an indication to such a proximity. Numerical simulation allowed to determine the structure of critical curves and caustics, formed by macro and microlenses, and to evaluate possible distortions, caused by microlenses for various locations with respect to the critical curve of a regular lens. The difference of our results from those obtained earlier with the standard (linearized) approach to describe the regular gravitational lens was shown to be the larger the closer to the critical curve the microlenses are situated. In addition to spatial redistributions in the visible images, complicated deformation of their light curves occurs in gravitational lensing of variable in time and extended sources. The magnitude of the temporal variations depend not only on the GL parameters (e.g., mass distribution), but on the parameters of the source as well, such as linear dimension of the emitting region, its location with respect to the critical curve, and the impulse duration. The analysis shows, that in this case GL acts as a filter, which passes slow temporal variations without degradations, and smoothes the rapid ones.

  3. Estimating permeability from quasi-static deformation: Temporal variations and arrival time inversion

    SciTech Connect (OSTI)

    Vasco, D.W.; Ferretti, Alessandro; Novali, Fabrizio

    2008-05-01T23:59:59.000Z

    Transient pressure variations within a reservoir can be treated as a propagating front and analyzed using an asymptotic formulation. From this perspective one can define a pressure 'arrival time' and formulate solutions along trajectories, in the manner of ray theory. We combine this methodology and a technique for mapping overburden deformation into reservoir volume change as a means to estimate reservoir flow properties, such as permeability. Given the entire 'travel time' or phase field, obtained from the deformation data, we can construct the trajectories directly, there-by linearizing the inverse problem. A numerical study indicates that, using this approach, we can infer large-scale variations in flow properties. In an application to Interferometric Synthetic Aperture (InSAR) observations associated with a CO{sub 2} injection at the Krechba field, Algeria, we image pressure propagation to the northwest. An inversion for flow properties indicates a linear trend of high permeability. The high permeability correlates with a northwest trending fault on the flank of the anticline which defines the field.

  4. Bois B., Wald L., Pieri P., Van Leeuwen C., Commagnac L., Chery Ph., Christen M., Gaudillre J.-P., Saur E., Estimating spatial and temporal variations in solar radiation within bordeaux winegrowing region using remotely

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    .-P., Saur E., Estimating spatial and temporal variations in solar radiation within bordeaux winegrowing-25, 2008. ESTIMATING SPATIAL AND TEMPORAL VARIATIONS IN SOLAR RADIATION WITHIN BORDEAUX WINEGROWING REGION presents a study solar radiation spatial and temporal variations in Bordeaux winegrowing area, for a 20

  5. Temporal Entropy Generation in the Viscous Layers of Laterally-converging Duct Flows

    SciTech Connect (OSTI)

    Donald M. McEligot; Robert S. Brodkey; Helmut Eckelmann

    2008-12-01T23:59:59.000Z

    Since insight into entropy generation is a key to increasing efficiency and thereby reducing fuel consumption and/or waste and -- for wall-bounded flows -- most entropy is generated in the viscous layer, we examine the transient behavior of its dominant contributor there for a non-canonical flow. New measurements in oil flow are presented for the effects of favorable streamwise mean pressure gradients on temporal entropy generation rates and, in the process, on key Reynolds-stress-producing events such as sweep front passage and on the deceleration/outflow phase of the overall bursting process. Two extremes have been considered: (1) a high pressure gradient, nearing "laminarization," and (2), for comparison, a low pressure gradient corresponding to many earlier experiments. In both cases, the peak temporal entropy generation rate occurs shortly after passage of the ejection/sweep interface. Whether sweep and ejection rates appear to decrease or increase with the pressure gradient depends on the feature examined and the manner of sampling. When compared using wall coordinates for velocities, distances and time, the trends and magnitudes of the transient behaviors are mostly the same. The main effects of the higher pressure gradient are (1) changes in the time lag between detections -- representing modification of the shape of the sweep front and the sweep angle with the wall, (2) modification of the magnitude of an instantaneous Reynolds shear stress with wall distance and (3) enlarging the sweeps and ejections. Results new for both low and high pressure gradients are the temporal behaviors of the dominant contribution to entropy generation; it is found to be much more sensitive to distance from the wall than to streamwise pressure gradient.

  6. An analysis of spatial and temporal variation in fecal indicator concentrations in Singapore

    E-Print Network [OSTI]

    Shin, Suejung

    2012-01-01T23:59:59.000Z

    This study used extensive measurements of indicator concentrations to describe spatial and temporal patterns of four fecal indicators: E. coli, enterococci, total coliform, and human factor. Twenty twelve-hour time series ...

  7. Three-dimensional instabilities in a discretely heated annular flow: Onset of spatio-temporal complexity via defect dynamics

    E-Print Network [OSTI]

    Marques, Francisco

    . INTRODUCTION Interest in natural convection in enclosures has a long history,1 motivated by both relevanceThree-dimensional instabilities in a discretely heated annular flow: Onset of spatio- temporal of the flow in an annular rotor-stator cavity Phys. Fluids 21, 064106 (2009); 10.1063/1.3156859 Stability

  8. Model for the spatio-temporal intermittency of the energy dissipation in turbulent flows

    E-Print Network [OSTI]

    Fabio Lepreti; Vincenzo Carbone; Pierluigi Veltri

    2007-02-08T23:59:59.000Z

    Modeling the intermittent behavior of turbulent energy dissipation processes both in space and time is often a relevant problem when dealing with phenomena occurring in high Reynolds number flows, especially in astrophysical and space fluids. In this paper, a dynamical model is proposed to describe the spatio-temporal intermittency of energy dissipation rate in a turbulent system. This is done by using a shell model to simulate the turbulent cascade and introducing some heuristic rules, partly inspired by the well known $p$-model, to construct a spatial structure of the energy dissipation rate. In order to validate the model and to study its spatially intermittency properties, a series of numerical simulations have been performed. These show that the level of spatial intermittency of the system can be simply tuned by varying a single parameter of the model and that scaling laws in agreement with those obtained from experiments on fully turbulent hydrodynamic flows can be recovered. It is finally suggested that the model could represent a useful tool to simulate the spatio-temporal intermittency of turbulent energy dissipation in those high Reynolds number astrophysical fluids where impulsive energy release processes can be associated to the dynamics of the turbulent cascade.

  9. Spatial and temporal climate variations influencing medium-range temperature predictions over south-central European Russia

    E-Print Network [OSTI]

    Johnson, Jeffrey Edward

    1990-01-01T23:59:59.000Z

    JOHNSON Approved as to style and content by: ohn F. Gri hs tChair of Cotnmittee) Steven W. L ons t 1VIember) . J. Freund Member) James R. Scoggins tHead of Department) May 1990 ABSTRACT Spatial and Temporal Climate Variations Influencing Medium... det. ailed climatology. A monthly overview f' or 9 stations in the region is given for the weather elements as stated above. Pentad and 3-hourly averages are also included. The detailed climatology is helpful in orienting a. new weather forecaster...

  10. Temporal Variations in the Effective Reproduction Number of the 2014 West Africa

    E-Print Network [OSTI]

    at the individual, regional, and national levels. Methods to provide real-time assessment of changing transmission Authors Sherry Towers Oscar Patterson-Lomba Carlos Castillo-Chavez Temporal Varia,ons in the Effec or the recently deceased, and the disease is particularly prone to transmission in unprotected homecare settings

  11. Analyzing the temporal variation of wind turbine responses using Gaussian Mixture Model and Gaussian Discriminant Analysis

    E-Print Network [OSTI]

    Stanford University

    such as loads, displacement, fatigue damages and power outputs. However, wind flow is a complex phenomenon Gaussian Discriminant Analysis, representative daytime and nocturnal wind turbine loads are compared, mean wind direction, turbulence intensity and power exponent quantifying the vertical profile

  12. Toposcale analyses of the temporal variations in the vertical distribution of moist-term refractivity

    E-Print Network [OSTI]

    Shumbera, August Leo, Jr

    1963-01-01T23:59:59.000Z

    OF FIGURES Figure Page Map showing location of Hanford Reservation, Hanford, Washington. 9 Variation in M as a function of Tw. . . . . . . 19 Surface isobaric and 700-mb analysis, 0400 PST, 13 August 1959. 24 Sounding for Reservation, 2115 PST, 13... direction and the 1/4- to 32-m mean wind speed for 24-hr period beginning 1900 PST, 11 August 1959. 41 Sounding for Hanford Reservation, 2330 PST, 11 August 1959. 43 14 Gradients of M and N for 16- to 32-m layer from 1900 PST, 11 August 1959 to 1900...

  13. Methanol as a Sensitive Probe for Spatial and Temporal Variations of the Proton-to-Electron Mass Ratio

    SciTech Connect (OSTI)

    Jansen, Paul; Ubachs, Wim; Bethlem, Hendrick L. [Institute for Lasers, Life and Biophotonics, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam (Netherlands); Xu Lihong [Department of Physics and Centre for Laser, Atomic, and Molecular Sciences, University of New Brunswick, Saint John, New Brunswick E2L 4L5 (Canada); Kleiner, Isabelle [Laboratoire Interuniversitaire des Systemes Atmospheriques (LISA), CNRS UMR 7583 et Universites Paris 7 et Paris Est, 61 avenue du General de Gaulle, 94010 Creteil Cedex (France)

    2011-03-11T23:59:59.000Z

    The 6.7 and 12.2 GHz masers, corresponding to the 5{sub 1}{yields}6{sub 0}A{sup +} and 2{sub 0}{yields}3{sub -1}E transitions in methanol (CH{sub 3}OH), respectively, are among the brightest radio objects in the sky. We present calculations for the sensitivity of these and other transitions in the ground state of methanol to a variation of the proton-to-electron mass ratio. We show that the sensitivity is greatly enhanced due to a cancellation of energies associated with the hindered internal rotation and the overall rotation of the molecule. We find sensitivities of K{sub {mu}=}-42 and K{sub {mu}=}-33, for the 5{sub 1}{yields}6{sub 0}A{sup +} and 2{sub 0}{yields}3{sub -1}E transitions, respectively. The sensitivities of other transitions in the different isotopologues of methanol range from -88 to 330. This makes methanol a sensitive probe for spatial and temporal variations of the proton-to-electron mass ratio.

  14. Detection of embedded radiation sources using temporal variation of gamma spectral data.

    SciTech Connect (OSTI)

    Shokair, Isaac R.

    2011-09-01T23:59:59.000Z

    Conventional full spectrum gamma spectroscopic analysis has the objective of quantitative identification of all the isotopes present in a measurement. For low energy resolution detectors, when photopeaks alone are not sufficient for complete isotopic identification, such analysis requires template spectra for all the isotopes present in the measurement. When many isotopes are present it is difficult to make the correct identification and this process often requires many trial solutions by highly skilled spectroscopists. This report investigates the potential of a new analysis method which uses spatial/temporal information from multiple low energy resolution measurements to test the hypothesis of the presence of a target spectrum of interest in these measurements without the need to identify all the other isotopes present. This method is referred to as targeted principal component analysis (TPCA). For radiation portal monitor applications, multiple measurements of gamma spectra are taken at equally spaced time increments as a vehicle passes through the portal and the TPCA method is directly applicable to this type of measurement. In this report we describe the method and investigate its application to the problem of detection of a radioactive localized source that is embedded in a distributed source in the presence of an ambient background. Examples using simulated spectral measurements indicate that this method works very well and has the potential for automated analysis for RPM applications. This method is also expected to work well for isotopic detection in the presence of spectrally and spatially varying backgrounds as a result of vehicle-induced background suppression. Further work is needed to include effects of shielding, to understand detection limits, setting of thresholds, and to estimate false positive probability.

  15. A Viscosity Approach to Total Variation Flows of Non-Divergence Type

    E-Print Network [OSTI]

    Ishii, Hitoshi

    A Viscosity Approach to Total Variation Flows of Non-Divergence Type Norbert Poz´ar Graduate School, we will introduce a notion of viscosity solutions for a class of singular nonlinear parabolic viscosity theory does not apply is the unboundedness of the operator on the right-hand side of (5) at u = 0

  16. Blood Pressure and Blood Flow Variation during Postural Change from Sitting to Standing: Model

    E-Print Network [OSTI]

    1 Blood Pressure and Blood Flow Variation during Postural Change from Sitting to Standing: Model that regulates blood pressure, and cerebral autoregulation that maintains cerebral perfusion. We present a mathematical model that can predict dynamic changes observed in beat-to-beat arterial blood pressure and middle

  17. Spatial and temporal variation of freely dissolved polycyclic aromatic hydrocarbons in an urban river undergoing Superfund remediation

    SciTech Connect (OSTI)

    Aregory James Sower; Kim A. Anderson [Oregon State University, Corvallis, OR (USA). Environmental and Molecular Toxicology Department

    2008-12-15T23:59:59.000Z

    Urban rivers with a history of industrial use can exhibit spatial and temporal variations in contaminant concentrations that may significantly affect risk evaluations and even the assessment of remediation efforts. Concentrations of 15 biologically available priority pollutant polycyclic aromatic hydrocarbons (PAHs) were measured over five years along 18.5 miles of the lower Willamette River using passive sampling devices and HPLC. The study area includes the Portland Harbor Superfund megasite with several PAH sources including remediation operations for coal tar at RM 6.3 west and an additional Superfund site, McCormick and Baxter, at RM 7 east consisting largely of creosote contamination. Study results show that organoclay capping at the McCormick and Baxter Superfund Site reduced PAHs from a precap average of 440 {+-} 422 ng/L to 8 {+-} 3 ng/L postcapping. Results also reveal that dredging of submerged coal tar nearly tripled nearby freely dissolved PAH concentrations. For apportioning sources, fluoranthene/pyrene and phenanthrene/anthracene diagnostic ratios from passive sampling devices were established for creosote and coal tar contamination and compared to published sediment values. 29 refs., 3 figs., 3 tabs.

  18. Temporal Variation in Estuarine Flows Relevant to Chemically-Mediated Predators

    E-Print Network [OSTI]

    on an intertidal mudflat at Priest Landing in Wassaw Sound, GA, USA over a 7 day period (6/4/09- 6/11/09). We

  19. HYDRODYNAMIC AND RADIATIVE MODELING OF TEMPORAL H{alpha} EMISSION V/R VARIATIONS CAUSED BY DISCONTINUOUS MASS TRANSFER IN BINARIES

    SciTech Connect (OSTI)

    Chadima, Pavel; Harmanec, Petr; Wolf, Marek [Astronomical Institute of the Charles University, Faculty of Mathematics and Physics, V Holesovickach 2, CZ-180 00 Praha 8 (Czech Republic); Firt, Roman [Mathematical Institute, University of Bayreuth, D-95447 Bayreuth (Germany); Ruzdjak, Domagoj; Bozic, Hrvoje [Hvar Observatory, Faculty of Geodesy, University of Zagreb, 10000 Zagreb (Croatia); Koubsky, Pavel, E-mail: pavel.chadima@gmail.com [Astronomical Institute of the Academy of Sciences, CZ-251 65 Ondrejov (Czech Republic)

    2011-07-15T23:59:59.000Z

    H{alpha} emission V/R variations caused by discontinuous mass transfer in interacting binaries with a rapidly rotating accreting star are modeled qualitatively for the first time. The program ZEUS-MP was used to create a non-linear three-dimensional hydrodynamical model of a development of a blob of gaseous material injected into an orbit around a star. It resulted in the formation of an elongated disk with a slow prograde revolution. The LTE radiative transfer program SHELLSPEC was used to calculate the H{alpha} profiles originating in the disk for several phases of its revolution. The profiles have the form of a double emission and exhibit V/R and radial velocity variations. However, these variations should be a temporal phenomenon since imposing a viscosity in the given model would lead to a circularization of the disk and fading-out of the given variations.

  20. Flow past superhydrophobic surfaces with cosine variation in local slip length

    E-Print Network [OSTI]

    Asmolov, Evgeny S; Harting, Jens; Vinogradova, Olga I

    2012-01-01T23:59:59.000Z

    Anisotropic super-hydrophobic surfaces have the potential to greatly reduce drag and enhance mixing phenomena in microfluidic devices. Recent work has focused mostly on cases of super-hydrophobic stripes. Here, we analyze a relevant situation of cosine variation of the local slip length. We derive approximate formulae for maximal (longitudinal) and minimal (transverse) directional effective slip lengths that are in good agreement with the exact numerical solution and lattice-Bolzmann simulations for any surface slip fraction. The cosine texture can provide a very large effective (forward) slip, but it was found to be less efficient in generating a transverse flow as compared to super-hydrophobic stripes.

  1. Surface tension of multi-phase flow with multiple junctions governed by the variational principle

    E-Print Network [OSTI]

    Shigeki Matsutani; Kota Nakano; Katsuhiko Shinjo

    2011-08-02T23:59:59.000Z

    We explore a computational model of an incompressible fluid with a multi-phase field in three-dimensional Euclidean space. By investigating an incompressible fluid with a two-phase field geometrically, we reformulate the expression of the surface tension for the two-phase field found by Lafaurie, Nardone, Scardovelli, Zaleski and Zanetti (J. Comp. Phys. \\vol{113} \\yr{1994} \\pages{134-147}) as a variational problem related to an infinite dimensional Lie group, the volume-preserving diffeomorphism. The variational principle to the action integral with the surface energy reproduces their Euler equation of the two-phase field with the surface tension. Since the surface energy of multiple interfaces even with singularities is not difficult to be evaluated in general and the variational formulation works for every action integral, the new formulation enables us to extend their expression to that of a multi-phase ($N$-phase, $N\\ge2$) flow and to obtain a novel Euler equation with the surface tension of the multi-phase field. The obtained Euler equation governs the equation of motion of the multi-phase field with different surface tension coefficients without any difficulties for the singularities at multiple junctions. In other words, we unify the theory of multi-phase fields which express low dimensional interface geometry and the theory of the incompressible fluid dynamics on the infinite dimensional geometry as a variational problem. We apply the equation to the contact angle problems at triple junctions. We computed the fluid dynamics for a two-phase field with a wall numerically and show the numerical computational results that for given surface tension coefficients, the contact angles are generated by the surface tension as results of balances of the kinematic energy and the surface energy.

  2. Fluid flow near reservoir lakes inferred from the spatial and temporal analysis of the electric potential

    E-Print Network [OSTI]

    Adolphs, Ralph

    , 2002. 1. Introduction [2] Detecting subsurface groundwater circulation using geophysical methods to result from the electrokinetic coupling associated with a vertical groundwater flow connecting a constant pore pressure source to the bottom of the lakes. Numerical modeling indicates that the spatial

  3. Trophic ecology of the invasive argentine ant: spatio-temporal variation in resource assimilation and isotopic enrichment

    E-Print Network [OSTI]

    Menke, Sean B.; Suarez, Andy V.; Tillberg, Chadwick V.; Chou, Cheng T.; Holway, David A.

    2010-01-01T23:59:59.000Z

    DOI 10.1007/s00442-010-1694-1 COMMUNITY ECOLOGY - ORIGINALPAPER Trophic ecology of the invasive argentine ant: spatio-variation in the trophic ecology of prominent members of

  4. Soil respiration and microbial biomass in a savanna parkland landscape: spatio-temporal variation and environmental controls

    E-Print Network [OSTI]

    McCulley, Rebecca Lynne

    1998-01-01T23:59:59.000Z

    ) in this region. The objective of this study was to quantify variation in soil respiration, soil microbial biomass (SMB), and potential C and N mineralization rates in relation to landscape heterogeneity and woody plant encroachment in this region. In addition...

  5. An isogeometric variational multiscale method for large-eddy simulation of coupled multi-ion transport in turbulent flow

    SciTech Connect (OSTI)

    Bauer, Georg; Gamnitzer, Peter [Institute for Computational Mechanics, Technische Universität München, Boltzmannstr. 15, 85747 Garching (Germany)] [Institute for Computational Mechanics, Technische Universität München, Boltzmannstr. 15, 85747 Garching (Germany); Gravemeier, Volker, E-mail: vgravem@lnm.mw.tum.de [Institute for Computational Mechanics, Technische Universität München, Boltzmannstr. 15, 85747 Garching (Germany) [Institute for Computational Mechanics, Technische Universität München, Boltzmannstr. 15, 85747 Garching (Germany); Emmy Noether Research Group “Computational Multiscale Methods for Turbulent Combustion”, Technische Universität München, Boltzmannstr. 15, 85747 Garching (Germany); Wall, Wolfgang A. [Institute for Computational Mechanics, Technische Universität München, Boltzmannstr. 15, 85747 Garching (Germany)] [Institute for Computational Mechanics, Technische Universität München, Boltzmannstr. 15, 85747 Garching (Germany)

    2013-10-15T23:59:59.000Z

    Highlights: •We present a computational method for coupled multi-ion transport in turbulent flow. •The underlying formulation is a variational multiscale finite element method. •It is combined with the isogeometric concept for electrochemical systems. •Coupled multi-ion transport in fully turbulent Taylor–Couette flow is simulated. •This example is an important model problem for rotating cylinder electrodes. -- Abstract: Electrochemical processes, such as electroplating of large items in galvanic baths, are often coupled to turbulent flow. In this study, we propose an isogeometric residual-based variational multiscale finite element method for multi-ion transport in dilute electrolyte solutions under turbulent flow conditions. In other words, this means that the concepts of isogeometric discretization and variational multiscale methods are successfully combined for developing a method capable of simulating the challenging problem of coupled multi-ion transport in turbulent flow. We present a comprehensive three-dimensional computational method taking into account, among others, coupled convection–diffusion-migration equations subject to an electroneutrality constraint in combination with phenomenological electrode-kinetics modeling. The electrochemical subproblem is one-way coupled to turbulent incompressible flow via convection. Ionic mass transfer in turbulent Taylor–Couette flow is investigated, representing an important model problem for rotating-cylinder-electrode configurations. Multi-ion transport as considered here is an example for mass transport at high Schmidt number (Sc=1389). An isogeometric discretization is especially advantageous for the present problem, since (i) curved boundaries can be represented exactly, and (ii) it has been proven to provide very accurate solutions for flow quantities when being applied in combination with residual-based variational multiscale modeling. We demonstrate that the method is robust and provides results which are in good agreement with direct numerical simulation results as well as empirical mass-transfer correlations reported in literature.

  6. Temporal and spatial variations of butyltin concentrations in bivalve and sediment samples from some coastal areas of the United States

    E-Print Network [OSTI]

    Garcia-Romero, Bernardo

    1988-01-01T23:59:59.000Z

    is not sensitive to non-norntal distributions and extreme values. These conditions may arise by excluding concentration values below 5 ng Sn/g and/or by sampling away from contamination point sources. This procedure is cquivalcnt to the Krustal-Waltis test, a... composition was significantly lower in August than during the other sampling months in 1986. The relative butyltin contamination in Galveston Bay was GBYC & GBCR & GBTD & GBHR. At the confidence level chosen (P & 0. 05), no significant spatial variation...

  7. Spatial and temporal variations in indoor environmental conditions, human occupancy, and operational characteristics in a new hospital building

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

    Ramos, Tiffanie; Dedesko, Sandra; Siegel, Jeffrey A.; Gilbert, Jack A.; Stephens, Brent

    2015-03-02T23:59:59.000Z

    The dynamics of indoor environmental conditions, human occupancy, and operational characteristics of buildings influence human comfort and indoor environmental quality, including the survival and progression of microbial communities. A suite of continuous, long-term environmental and operational parameters were measured in ten patient rooms and two nurse stations in a new hospital building in Chicago, IL to characterize the indoor environment in which microbial samples were taken for the Hospital Microbiome Project. Measurements included environmental conditions (indoor dry-bulb temperature, relative humidity, humidity ratio, and illuminance) in the patient rooms and nurse stations; differential pressure between the patient rooms and hallways; surrogatemore »measures for human occupancy and activity in the patient rooms using both indoor air CO? concentrations and infrared doorway beam-break counters; and outdoor air fractions in the heating, ventilating, and air-conditioning systems serving the sampled spaces. Measurements were made at 5-minute intervals over consecutive days for nearly one year, providing a total of ~8×10? data points. Indoor temperature, illuminance, and human occupancy/activity were all weakly correlated between rooms, while relative humidity, humidity ratio, and outdoor air fractions showed strong temporal (seasonal) patterns and strong spatial correlations between rooms. Differential pressure measurements confirmed that all patient rooms were operated at neutral pressure. The patient rooms averaged about 100 combined entrances and exits per day, which suggests they were relatively lightly occupied compared to higher traffic environments (e.g., retail buildings) and more similar to lower traffic office environments. There were also clear differences in several environmental parameters before and after the hospital was occupied with patients and staff. Characterizing and understanding factors that influence these building dynamics is vital for hospital environments, where they can impact patient health and the survival and spread of healthcare associated infections.« less

  8. Carbonaceous aerosols recorded in a southeastern Tibetan glacier: analysis of temporal variations and model estimates of sources and radiative forcing

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

    Wang, Mo; Xu, B.; Cao, J.; Tie, X.; Wang, Hailong; Zhang, Rudong; Qian, Yun; Rasch, Philip J.; Zhao, Shuyu; Wu, Guangjian; et al

    2015-01-01T23:59:59.000Z

    High temporal resolution measurements of black carbon (BC) and organic carbon (OC) covering the time period of 1956–2006 in an ice core over the southeastern Tibetan Plateau show a distinct seasonal dependence of BC and OC with higher respective concentrations but a lower OC / BC ratio in the non-monsoon season than during the summer monsoon. We use a global aerosol-climate model, in which BC emitted from different source regions can be explicitly tracked, to quantify BC source–receptor relationships between four Asian source regions and the southeastern Tibetan Plateau as a receptor. The model results show that South Asia hasmore »the largest contribution to the present-day (1996–2005) mean BC deposition at the ice-core drilling site during the non-monsoon season (October to May) (81%) and all year round (74%), followed by East Asia (14% to the non-monsoon mean and 21% to the annual mean). The ice-core record also indicates stable and relatively low BC and OC deposition fluxes from the late 1950s to 1980, followed by an overall increase to recent years. This trend is consistent with the BC and OC emission inventories and the fuel consumption of South Asia (as the primary contributor to annual mean BC deposition). Moreover, the increasing trend of the OC / BC ratio since the early 1990s indicates a growing contribution of coal combustion and/or biomass burning to the emissions. The estimated radiative forcing induced by BC and OC impurities in snow has increased since 1980, suggesting an increasing potential influence of carbonaceous aerosols on the Tibetan glacier melting and the availability of water resources in the surrounding regions. Our study indicates that more attention to OC is merited because of its non-negligible light absorption and the recent rapid increases evident in the ice-core record.« less

  9. Carbonaceous Aerosols Recorded in a Southeastern Tibetan Glacier: Analysis of Temporal Variations and Model Estimates of Sources and Radiative Forcing

    SciTech Connect (OSTI)

    Wang, Mo; Xu, B.; Cao, J.; Tie, X.; Wang, Hailong; Zhang, Rudong; Qian, Yun; Rasch, Philip J.; Zhao, Shuyu; Wu, Guangjian; Zhao, Huabiao; Joswiak, Daniel R.; Li, Jiule; Xie, Ying

    2015-01-01T23:59:59.000Z

    High temporal resolution measurements of black carbon (BC) and organic carbon (OC) covering the time period of 1956-2006 in an ice core over the southeastern Tibetan Plateau show a distinct seasonal dependence of OC/BC ratio with higher values in the non-monsoon season than during the summer monsoon. We use a global aerosol-climate model, in which BC emitted from different source regions can be explicitly tracked, to quantify BC source-receptor relationships between four Asian source regions and the southern Tibetan Plateau as a receptor. The model results show that South Asia is a primary contributor during the non-monsoon season (October to May) (81%) and on an annual basis (74%), followed by East Asia (14% and 21%, respectively). The ice-core record also indicates stable and relatively low BC and OC deposition fluxes from late 1950s to 1980, followed by an overall increase to recent years. This trend is consistent with the BC and OC emission inventories and the fuel consumption of South Asia as the primary contributor. Moreover, the increasing trend of OC/BC ratio since the early 1990s indicates a growing contribution of coal combustion and biomass burning to the emissions. The estimated radiative forcing induced by BC/OC impurities in snow has increased since 1980, suggesting an increasing influence of carbonaceous aerosols on the Tibetan glacier melting, influencing the availability of water resources in the surrounding regions. Our study indicates that the role of OC deserves more attention because of its non-negligible light absorption and the more rapid increase than BC

  10. Variational bounds on the energy dissipation rate in body-forced shear flow

    E-Print Network [OSTI]

    Petrov, Nikola

    , the bulk (space and time averaged) dissipation rate per unit mass is proportional to the power required applied to many flows driven by boundary conditions, including shear flows and a variety of thermal

  11. NUMERICAL METHODS FOR ANISOTROPIC MEAN CURVATURE FLOW BASED ON A DISCRETE TIME VARIATIONAL

    E-Print Network [OSTI]

    Soatto, Stefano

    . This variational approach was studied in [ATW93, LS95, CN07]. The level set method (see Section 1.2) can also

  12. Macroroughness and variations in reach-averaged flow resistance in steep mountain streams

    E-Print Network [OSTI]

    Kirchner, James W.

    , boulder diameter and protrusion, and roughness of longitudinal channel profiles in six reaches of steep equation for flow velocity. The predictions were better than predictions by the variable power law equation intakes, and other infrastructure in or near streams. To accurately predict bed load transport rates

  13. Simulations of Turbulent Flows with Strong Shocks and Density Variations: Final Report

    SciTech Connect (OSTI)

    Sanjiva Lele

    2012-10-01T23:59:59.000Z

    The target of this SciDAC Science Application was to develop a new capability based on high-order and high-resolution schemes to simulate shock-turbulence interactions and multi-material mixing in planar and spherical geometries, and to study Rayleigh-Taylor and Richtmyer-Meshkov turbulent mixing. These fundamental problems have direct application in high-speed engineering flows, such as inertial confinement fusion (ICF) capsule implosions and scramjet combustion, and also in the natural occurrence of supernovae explosions. Another component of this project was the development of subgrid-scale (SGS) models for large-eddy simulations of flows involving shock-turbulence interaction and multi-material mixing, that were to be validated with the DNS databases generated during the program. The numerical codes developed are designed for massively-parallel computer architectures, ensuring good scaling performance. Their algorithms were validated by means of a sequence of benchmark problems. The original multi-stage plan for this five-year project included the following milestones: 1) refinement of numerical algorithms for application to the shock-turbulence interaction problem and multi-material mixing (years 1-2); 2) direct numerical simulations (DNS) of canonical shock-turbulence interaction (years 2-3), targeted at improving our understanding of the physics behind the combined two phenomena and also at guiding the development of SGS models; 3) large-eddy simulations (LES) of shock-turbulence interaction (years 3-5), improving SGS models based on the DNS obtained in the previous phase; 4) DNS of planar/spherical RM multi-material mixing (years 3-5), also with the two-fold objective of gaining insight into the relevant physics of this instability and aiding in devising new modeling strategies for multi-material mixing; 5) LES of planar/spherical RM mixing (years 4-5), integrating the improved SGS and multi-material models developed in stages 3 and 5. This final report is outlined as follows. Section 2 shows an assessment of numerical algorithms that are best suited for the numerical simulation of compressible flows involving turbulence and shock phenomena. Sections 3 and 4 deal with the canonical shock-turbulence interaction problem, from the DNS and LES perspectives, respectively. Section 5 considers the shock-turbulence inter-action in spherical geometry, in particular, the interaction of a converging shock with isotropic turbulence as well as the problem of the blast wave. Section 6 describes the study of shock-accelerated mixing through planar and spherical Richtmyer-Meshkov mixing as well as the shock-curtain interaction problem In section 7 we acknowledge the different interactions between Stanford and other institutions participating in this SciDAC project, as well as several external collaborations made possible through it. Section 8 presents a list of publications and presentations that have been generated during the course of this SciDAC project. Finally, section 9 concludes this report with the list of personnel at Stanford University funded by this SciDAC project.

  14. Spatial and Temporal Variation of Elemental Deposition in Maricopa County T. Zschau1, S. Getty2, C. Gries1, T.H. Nash III1

    E-Print Network [OSTI]

    Hall, Sharon J.

    %, a pattern that reflects the switch to unleaded gasoline. Similarly the closure of the Ajo smelter has of old smelter. Temporal trends: Levels remain fairly constant for most parts of the county. A sharp decline in the south is related to closure of Ajo smelter in 1986. Lead: Spatial: Concentrated

  15. Temporal implicatures

    E-Print Network [OSTI]

    Thomas, Guillaume (Guillaume Pierre Yves)

    2012-01-01T23:59:59.000Z

    This dissertation proposes a theory of temporal implicatures, and applies it to the study of tense in Mbyá Guaraní. It is composed of two parts. In the first one, I discuss the analyses of temporal implicatures developed ...

  16. Computations of Viscous Compressible Flows in h, p, k Finite Element Framework with Variationally Consistent Integral Forms

    E-Print Network [OSTI]

    Allu, Srikanth

    2008-01-31T23:59:59.000Z

    viscous form of Burgers equation, 1-D Riemann shock tube with ideal and real gas models and Boundary Value Problems in 2-D compressible flow : Carter's plate with Mach 1, 2, 3 and 5 flows and Mach 1 flow past a circular cylinder are used as model problems...

  17. Bi-Annual Report 2010-2011: Shaping pulse flows to meet environmental and energy objectives

    SciTech Connect (OSTI)

    Jager, Yetta [ORNL

    2010-10-01T23:59:59.000Z

    This report describes a bioenergetic model developed to allocate seasonal pulse flows to benefit salmon growth. The model links flow with floodplain inundation and production of invertebrate prey eaten by juvenile Chinook salmon. A unique quantile modeling approach is used to describe temporal variation among juvenile salmon spawned at different times. Preliminary model outputs are presented and future plans to optimize flows both to maximize salmon growth and hydropower production are outlined.

  18. Temporal variations of mineral dust, biogenic tracers, and anthropogenic species during the past two centuries from Belukha ice core, Siberian Altai - article no. D05309

    SciTech Connect (OSTI)

    Olivier, S.; Blaser, C.; Brutsch, S.; Frolova, N.; Gaggeler, H.W.; Henderson, K.A.; Palmer, A.S.; Papina, T.; Schwikowski, M. [Paul Scherrer Institute, Villigen (Switzerland)

    2006-03-07T23:59:59.000Z

    In July 2001, a 140 m long ice core was recovered from the Belukha glacier (49 degrees 48'26''N, 86 degrees 34'43''E, 4062 m a.s.l.) in the Siberian Altai. The ion chemistry of the upper 86 m, covering the last two centuries, is characterized by biogenic emissions (ammonium and formate), aeolian dust (calcium, magnesium, chloride, and sodium) and anthropogenic species (sulfate, nitrate, and ammonium). Particularly high ammonium and formate concentrations indicate pronounced emissions from Siberian forests. The inferred fire frequency does not show a long-term trend but distinct periods of enhanced activity. Sulfate has the highest industrial to preindustrial ratio and an anthropogenic contribution of more than 80%. Variations in this record reflect sulfur dioxide emissions in Siberia and Kazakhstan. Sulfate concentrations remained low until 1950, then sharply increased and peaked in the 1970s. The decrease in the 1980s is attributed to the economic, political, and social crises and to the replacement of coal with gas. Rising nitrate concentrations since 1960 reflect traffic growth and enhanced fertilizer application. Increasing ammonium concentrations since the 1950s are attributable to population inflow in southern Siberia with the associated enhancement of agricultural activity. A nitrate peak of short duration in 1908 is thought to be the atmospheric signature from the Tunguska event on 30 June 1908.

  19. Source Characterization and Temporal Variation of Methane Seepage from Thermokarst Lakes on the Alaska North Slope in Response to Arctic Climate Change

    SciTech Connect (OSTI)

    None

    2012-09-30T23:59:59.000Z

    The goals of this research were to characterize the source, magnitude and temporal variability of methane seepage from thermokarst lakes (TKL) within the Alaska North Slope gas hydrate province, assess the vulnerability of these areas to ongoing and future arctic climate change and determine if gas hydrate dissociation resulting from permafrost melting is contributing to the current lake emissions. Analyses were focused on four main lake locations referred to in this report: Lake Qalluuraq (referred to as Lake Q) and Lake Teshekpuk (both on Alaska?s North Slope) and Lake Killarney and Goldstream Bill Lake (both in Alaska?s interior). From analyses of gases coming from lakes in Alaska, we showed that ecological seeps are common in Alaska and they account for a larger source of atmospheric methane today than geologic subcap seeps. Emissions from the geologic source could increase with potential implications for climate warming feedbacks. Our analyses of TKL sites showing gas ebullition were complemented with geophysical surveys, providing important insight about the distribution of shallow gas in the sediments and the lake bottom manifestation of seepage (e.g., pockmarks). In Lake Q, Chirp data were limited in their capacity to image deeper sediments and did not capture the thaw bulb. The failure to capture the thaw bulb at Lake Q may in part be related to the fact that the present day lake is a remnant of an older, larger, and now-partially drained lake. These suggestions are consistent with our analyses of a dated core of sediment from the lake that shows that a wetland has been present at the site of Lake Q since approximately 12,000 thousand years ago. Chemical analyses of the core indicate that the availability of methane at the site has changed during the past and is correlated with past environmental changes (i.e. temperature and hydrology) in the Arctic. Discovery of methane seeps in Lake Teshekpuk in the northernmost part of the lake during 2009 reconnaissance surveys provided a strong impetus to visit this area in 2010. The seismic methods applied in Lake Teshekpuk were able to image pockmarks, widespread shallow gas in the sediments, and the relationship among different sediment packages on the lake?s bottom, but even boomer seismics did not detect permafrost beneath the northern part of the lake. By characterizing the biogeochemistry of shallow TKL with methane seeps we showed that the radical seasonal shifts in ice cover and temperature. These seasonal environmental differences result in distinct consumption and production processes of biologically-relevant compounds. The combined effects of temperature, ice-volume and other lithological factors linked to seepage from the lake are manifest in the distribution of sedimentary methane in Lake Q during icecovered and ice-free conditions. The biogeochemistry results illustrated very active methanotrophy in TKLs. Substantial effort was subsequently made to characterize the nature of methanotrophic communities in TKLs. We applied stable isotope probing approaches to genetically characterize the methanotrophs most active in utilizing methane in TKLs. Our study is the first to identify methane oxidizing organisms active in arctic TKLs, and revealing that type I methanotrophs and type II methanotrophs are abundant and active in assimilating methane in TKLs. These organisms play an important role in limiting the flux of methane from these sites. Our investigations indicate that as temperatures increase in the Arctic, oxidation rates and active methanotrophic populations will also shift. Whether these changes can offset predicted increases in methanogenesis is an important question underlying models of future methane flux and resultant climate change. Overall our findings indicate that TKLs and their ability to act as both source and sink of methane are exceedingly sensitive to environmental change.

  20. Variation of Fish Habitat and Extent of the Low-Salinity Zone with Freshwater Flow in the San Francisco Estuary

    E-Print Network [OSTI]

    Kimmerer, Wim J.; MacWilliams, Michael L.; Gross, Edward S.

    2013-01-01T23:59:59.000Z

    prey, and fish early-life histories to striped bass Moroneby striped bass larvae. Trans Am Fish Soc 117(1):72–77.fish, freshwater flow, resource selec- tion function, delta smelt, longfin smelt, striped bass,

  1. Flow geometry variation of IGR 17091-3624 as revealed by Comptonizing Efficiency and its comparison with GRS 1915+105

    E-Print Network [OSTI]

    Pal, Partha Sarathi

    2015-01-01T23:59:59.000Z

    Variability class transitions in the enigmatic black hole candidate GRS 1915+105 has been known to accompany variation of distinct flow geometry as is evidenced by the behavior of Comptonizing Efficiency (CE). This dynamical hardness ratio is defined to be the ratio between the number of power-law (hard) photons and injected seed (soft) photons and to some extent represent the geometry of the so-called Compton cloud. Similarities of light curves in some variability classes in GRS 1915+105 and IGR 17091-3624 have been reported in the literature. In the present paper, we present some more variability classes for which the light curves are similar. We examine CE variations in all these light curves of IGR 17091-3624 and find that they are also similar to what was reported for GRS 1915+105, even though masses of these objects are believed to be widely different. This shows that characterization of variability classes based on dynamical hardness ratios or CEs is likely to be black hole mass independent.

  2. Complex temporal and spatial patterns in nonequilibrium systems

    SciTech Connect (OSTI)

    Swinney, H.L.

    1991-09-01T23:59:59.000Z

    Dynamical systems methods are being developed and used to characterize the formation and evolution of temporal and spatial patterns in systems maintained far from equilibrium. In particular, experiments and analyses are considering electrodeposition of fractal metallic clusters, pattern formation in reaction-diffusion systems, and the primary instabilities of some fluid flows. Novel reactors have been developed to search for chemical patterns (spatial variations in the chemical composition), and sustained patterns have been found in several different one- and two-dimensional geometries. Bifurcations in these patterns are studied by varying control parameters, e.g., the concentrations of the feed chemicals or the temperature. The observed two-dimensional chemical patterns range from the stationary patterns, similar to those predicted by Turing in 1952 but not observed until 1990, to chemical turbulence, which is characterized by large numbers of defects and a rapid decay of spatial correlations. These provide general insights into the formation of spatiotemporal patterns in nonequilibrium systems.

  3. Cooling Flows or Heating Flows?

    E-Print Network [OSTI]

    James Binney

    2003-10-08T23:59:59.000Z

    It is now clear that AGN heat cooling flows, largely by driving winds. The winds may contain a relativistic component that generates powerful synchrotron radiation, but it is not clear that all winds do so. The spatial and temporal stability of the AGN/cooling flow interaction are discussed. Collimation of the winds probably provides spatial stability. Temporal stability may be possible only for black holes with masses above a critical value. Both the failure of cooling flows to have adiabatic cores and the existence of X-ray cavities confirm the importance of collimated outflows. I quantify the scale of the convective flow that the AGN Hydra would need to drive if it balanced radiative inward flow by outward flow parallel to the jets. At least in Virgo any such flow must be confined to r<~20 kpc. Hydrodynamical simulations suggest that AGN outbursts cannot last longer than ~25 Myr. Data for four clusters with well studied X-ray cavities suggests that heating associated with cavity formation approximately balances radiative cooling. The role of cosmic infall and the mechanism of filament formation are briefly touched on.

  4. Anomalous diffusion in bounded temporally irregular flows

    E-Print Network [OSTI]

    Venkataramani, Shankar C.

    Department of Physics, Department of Electrical Engineering and Institute for Plasma Research, University

  5. Correcting the record on the analysis of IBEX and STEREO data regarding variations in the neutral interstellar wind

    E-Print Network [OSTI]

    Frisch, P C; Drews, C; Leonard, T; Livadiotis, G; McComas, D J; Moebius, E; Schwadron, N A; Sokol, J M

    2015-01-01T23:59:59.000Z

    The journey of the Sun through space carries the solar system through a dynamic interstellar environment that is presently characterized by Mach 1 motion between the heliosphere and the surrounding interstellar medium (ISM). The interaction between the heliosphere and ISM is an evolving process due to the variable solar wind and to interstellar turbulence. Frisch et al. presented a meta-analysis of the historical data on the interstellar wind flowing through the heliosphere and concluded that temporal changes in the ecliptic longitude of the wind were statistically indicated by the data available in the refereed literature at the time of that writing. Lallement and Bertaux disagree with this result, and suggested, for instance, that a key instrumental response function of IBEX-Lo was incorrect and that the STEREO pickup ion data are unsuitable for diagnosing the flow of interstellar neutrals through the heliosphere. Here we show that temporal variations in the interstellar wind through the heliosphere are con...

  6. Doing time : inducing temporal graphs

    E-Print Network [OSTI]

    Bramsen, Philip James

    2006-01-01T23:59:59.000Z

    We consider the problem of constructing a directed acyclic graph that encodes temporal relations found in a text. The unit of our analysis is a temporal segment, a fragment of text that maintains temporal coherence. The ...

  7. Markov Temporal Logic Wojciech Jamroga

    E-Print Network [OSTI]

    Zachmann, Gabriel

    Richter (Technical Computer Science) Prof. Dr. Gabriel Zachmann (Computer Graphics) #12;Markov Temporal

  8. An initial look at the dynamics of the microscale flow field within a large wind farm in response to variations in the natural inflow

    SciTech Connect (OSTI)

    Kelley, N.D.

    1989-10-01T23:59:59.000Z

    This paper discusses some early results from a study to examine the influence of the natural inflow structure on the internal microscale turbulence environment of a large wind farm. Two fully equipped, high-resolution boundary layer measurement systems were employed to document the alteration of the turbulent structure as the flow entered and left a wind park consisting of 41 rows of turbines. These systems collected data continuously for a period of several weeks during the peak wind season in San Gorgonio Pass. In addition, statistical summaries of the inflow and outflow characteristics from a hub-height elevation were recorded prior to, during and after the detailed measurement period. Results of these hub-height summaries will be discussed and interpreted in this paper. 11 figs.

  9. Spatial pattern and temporal dynamics of northern bobwhite abundance and agricultural landuse, and potential casual factors 

    E-Print Network [OSTI]

    Okay, Atiye Zeynep

    2006-04-12T23:59:59.000Z

    There was a long-term decline in northern bobwhite (Colinus virginianus, NBW) abundance since the 1920s, based on the Christmas Bird Count (CBC) data, but with substantial spatial and temporal variations across its range. ...

  10. Analysis and visualization of temporal variations in video

    E-Print Network [OSTI]

    Rubinstein, Michael, Ph. D. Massachusetts Institute of Technology

    2014-01-01T23:59:59.000Z

    Our world is constantly changing, and it is important for us to understand how our environment changes and evolves over time. A common method for capturing and communicating such changes is imagery - whether captured by ...

  11. Temporal Velocity Variations beneath the Coso Geothermal Field...

    Open Energy Info (EERE)

    Field Observed using Seismic Double Difference Tomography of Compressional and Shear Wave Arrival Times Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference...

  12. Temporal Variation in Fish Communities Off Santa Cruz Island, California

    E-Print Network [OSTI]

    Larson, Ralph

    2008-01-01T23:59:59.000Z

    at sub-tidal reefs and kelp beds at Santa Cruz Island in theand/or by the loss of giant kelp, which occurs during warm-diminishing the extent of giant kelp beds. Student Michelle

  13. Temporal Variation in Fish Communities off Santa Cruz Island, California

    E-Print Network [OSTI]

    Graves, Michelle R.; Larson, Ralph J.; Alevizon, William S.

    2006-01-01T23:59:59.000Z

    mean log count mean log count Kelp perch Olive rockfish meancount mean log count Opaleye Kelp coverage mean lkelp scoreLerma D, Richards D. 1999. Kelp Forest Monitoring Handbook,

  14. Spatial and Temporal Variations of Groundwater Arsenic in South and

    E-Print Network [OSTI]

    van Geen, Alexander

    in rural areas throughout the major river basins draining the Himalayas have become the main source. Arsenic enters groundwater naturally from rocks and sediment by coupled biogeochemical and hydrologic population exposed to unsafe As levels by drinking untreated groundwater in India, China, Myanmar, Pakistan

  15. Variation in temporal [14 photosynthesis among warm monomictic

    E-Print Network [OSTI]

    Mazumder, Asit

    , DEPARTMENT OF BIOLOGY, UNIVERSITY OF VICTORIA, PO BOX 3020 STN CSC, VICTORIA, BC V8N 3N5, CANADA). In ice-covered lakes $10% of annual areal PP occurs under ice [range 2% to >30% (Alvarez- Cobelas isothermal conditions in Lake Michigan and that this was also an important time of new production. Coastal

  16. TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES IN THE

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f <Maintained By FaultSunpodsSweetwater 4aSyntheticTAU SolarTDKCOSO

  17. Temporal Velocity Variations beneath the Coso Geothermal Field Observed

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f <Maintained ByManagement IncDrillbe nice if logos couldCalifornia:using

  18. Temporal Geochemical Variations In Volatile Emissions From Mount St Helens,

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries PvtStratosolar Jump to:HoldingsTechintIsNumeric JumpTerrace,

  19. assessing meiofaunal variation: Topics by E-print Network

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

    of Constants . . . . . . . . . . . . . . . . . . . . . . 20 3.1.1 Flow Graphs Mller-Olm, Markus 356 Multiobjective Optimization Problem with Variational Inequality Constraints...

  20. acute postural variation: Topics by E-print Network

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

    of Constants . . . . . . . . . . . . . . . . . . . . . . 20 3.1.1 Flow Graphs Mller-Olm, Markus 469 Multiobjective Optimization Problem with Variational Inequality Constraints...

  1. arecaceae biogeographic variation: Topics by E-print Network

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

    of Constants . . . . . . . . . . . . . . . . . . . . . . 20 3.1.1 Flow Graphs Mller-Olm, Markus 317 Multiobjective Optimization Problem with Variational Inequality Constraints...

  2. Temporal Representation in Semantic Graphs

    SciTech Connect (OSTI)

    Levandoski, J J; Abdulla, G M

    2007-08-07T23:59:59.000Z

    A wide range of knowledge discovery and analysis applications, ranging from business to biological, make use of semantic graphs when modeling relationships and concepts. Most of the semantic graphs used in these applications are assumed to be static pieces of information, meaning temporal evolution of concepts and relationships are not taken into account. Guided by the need for more advanced semantic graph queries involving temporal concepts, this paper surveys the existing work involving temporal representations in semantic graphs.

  3. Temporal dosimeter and method

    DOE Patents [OSTI]

    Warner, Benjamin P.; Lopez, Thomas A.

    2003-09-30T23:59:59.000Z

    The invention includes a temporal dosimeter. One dosimeter embodiment includes a housing that is opaque to visible light but transparent to ionizing radiation. The dosimeter also includes a sensor for recording dosages of ionizing radiation, a drive mechanism, a power source, and rotatable shields that work together to produce a compound aperture to unveil different portions of the sensor at different times to ionizing radiation. Another dosimeter embodiment includes a housing, a sensor, a shield with an aperture portion, and a linear actuator drive mechanism coupled to the sensor for moving the sensor past the aperture portion. The sensor turns as it moves past the aperture, tracing a timeline record of exposure to ionizing radiation along a helical path on the sensor.

  4. TEMPORAL DATA WAREHOUSING a dissertation

    E-Print Network [OSTI]

    Pratt, Vaughan

    of information available to large-scale enterprises is growing rapidly. New information is being generated. To support eÆcient analysis and mining of such diverse, distributed information, a data warehousing system for temporal data, and a temporal data warehousing prototype supporting incremental maintenance based

  5. Solar-cycle variation of the sound-speed asphericity from GONG and MDI data 1995-2000

    E-Print Network [OSTI]

    H. M. Antia; S. Basu; F. Hill; R. Howe; R. W. Komm; J. Schou

    2001-09-19T23:59:59.000Z

    We study the variation of the frequency splitting coefficients describing the solar asphericity in both GONG and MDI data, and use these data to investigate temporal sound-speed variations as a function of both depth and latitude during the period from 1995-2000 and a little beyond. The temporal variations in even splitting coefficients are found to be correlated to the corresponding component of magnetic flux at the solar surface. We confirm that the sound-speed variations associated with the surface magnetic field are superficial. Temporally averaged results show a significant excess in sound speed around 0.92 solar radii and latitude of 60 degrees.

  6. Amos Storkey, School of Informatics. Temporal and Spatio-Temporal

    E-Print Network [OSTI]

    Edinburgh, University of

    scale parallel particle filters for stochastic differential systems Applied to fMRI. Looking for other Spiliopoulou, Bessi Bjarnason. #12;Amos Storkey, School of Informatics. Overall Goal Temporal Systems Model

  7. Spatiotemporal variation in survival rates: implications for population dynamics of yellow-bellied marmots

    E-Print Network [OSTI]

    Ozgul, Arpat; Armitage, Kenneth; Blumstein, Daniel T.; Oli, Madan K.

    2006-04-01T23:59:59.000Z

    Spatiotemporal variation in age-specific survival rates can profoundly influence population dynamics, but few studies of vertebrates have thoroughly investigated both spatial and temporal variability in age-specific survival rates. We used 28 years...

  8. VARIATIONS IN THE HELIOSPHERIC POLAR ENERGETIC NEUTRAL ATOM FLUX OBSERVED BY THE INTERSTELLAR BOUNDARY EXPLORER

    E-Print Network [OSTI]

    Reisenfeld, D. B.

    The ecliptic poles are observed continuously by the Interstellar Boundary Explorer (IBEX); thus, it is possible to discern temporal variations in the energetic neutral atoms (ENAs) from the outer heliosphere on timescales ...

  9. Geographic variation in Elaphe guttata (Linnaeus) (Serpentes: Colubridae

    E-Print Network [OSTI]

    Thomas, Robert Allen

    1974-01-01T23:59:59.000Z

    of supralabials entering orbit , . . . 28 3. Distribution of different postocular combinations . . . , , . . . . . . ~ . . . . 30 Temporal combinations observed in ~Ela he g tt ta . . 5. Distribution of the different infra- ~ ~ 31 labial combinations... scales 'n ~Ela he gutta* . . . . . 35 North-south geographic variation in numbers of ventrals plus subcaudals in ~Ela he g ttat 5 ~ West-east geographic variation in numbers of ventrals plus subcaudals in ~Ela he g tta*a 6 ~ West-east geographic...

  10. Spontaneous bursting: From temporal to spatio-temporal intermittency

    SciTech Connect (OSTI)

    Platt, N.; Hammel, S.M. [Code B44, Nonlinear Dynamics and Wavelets Group, Naval Surface Warfare Center, 10901 New Hampshire Ave, Silver Spring, Maryland, 20903-5640 (United States)

    1996-06-01T23:59:59.000Z

    A simple model for temporal bursting is introduced. This model invokes either dynamic or random forcing of a bifurcation parameter of some simple dynamical system in a way that makes the bifurcation parameter spend suitable amounts of time below and above the bifurcation threshold. This model is extended to coupled map lattices to produce spontaneous spatio-temporal burstings. It models physical systems which are embedded in a random background that is statistically homogeneous in space and time. An application of this model to optical turbulence is discussed. {copyright} {ital 1996 American Institute of Physics.}

  11. Variations of surface water extent and water storage in large river basins: A comparison of different global data sources

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of the spatio-temporal variations of total terrestrial water storage (the sum of ground water, soil water1 Variations of surface water extent and water storage in large river basins: A comparison mass variations monitored by GRACE, simulated surface and total water storage from WGHM, water levels

  12. (, 310027) An Efficient Method for Surface Simplification Based On Variational Shape

    E-Print Network [OSTI]

    Liu, Ligang

    mesh ( chart rox (a) bunny , 69451 c) Fig. 1 Flow of variational shape app imation 1 #12;4 3 of the model. The paper presents a local greedy algorithm to minimize the energy defined by variational shape

  13. adh1a variation predisposes: Topics by E-print Network

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

    of Constants . . . . . . . . . . . . . . . . . . . . . . 20 3.1.1 Flow Graphs Mller-Olm, Markus 287 Multiobjective Optimization Problem with Variational Inequality Constraints...

  14. Variational Methods Michael Moeller

    E-Print Network [OSTI]

    Cremers, Daniel

    Continuous dependence Regularization Design Total Variation updated 09.12.2014 Generalization A quantum leap Regularization Design Total Variation updated 09.12.2014 Generalization A quantum leap forward! · Imagine F

  15. Observations and simulations of synoptic, regional, and local variations in atmospheric CO2

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    Observations and simulations of synoptic, regional, and local variations in atmospheric CO2 Jih] Synoptic events may play an important role in determining the CO2 spatial distribution and temporal 2001, which had the most significant CO2 concentration variation in our case pool. The CO2

  16. Temporal Specifications with Accumulative Values

    E-Print Network [OSTI]

    Boker, Udi

    Temporal Specifications with Accumulative Values Udi Boker, Krishnendu Chatterjee, Thomas A the accumulation of values along a computation. It is either the accumulated summation, as with the energy objectives, or the accumulated average, as with the mean-payoff objectives. We investigate the extension

  17. Active Temporal Multiplexing of Photons

    E-Print Network [OSTI]

    Gabriel J. Mendoza; Raffaele Santagati; Jack Munns; Elizabeth Hemsley; Mateusz Piekarek; Enrique Martin-Lopez; Graham D. Marshall; Damien Bonneau; Mark G. Thompson; Jeremy L. O'Brien

    2015-03-04T23:59:59.000Z

    Quantum information science promises powerful new technologies and fundamental scientific discoveries. Photonic qubits are appealing for their low noise properties-the cost is the non-deterministic nature of many processes, including photon generation and entanglement. Active multiplexing can increase the success probability of such processes above a required threshold, and spatial multiplexing of up to four heralded photon sources shows great promise. The cost is a proliferation of hardware. Temporal multiplexing-repeated use of the same hardware components-has been proposed as an alternative and is likely to be essential to greatly reduce resource complexity and system sizes. Requirements include the precise synchronization of a system of low-loss switches, delay lines, fast photon detectors, and feed-forward. Here we demonstrate multiplexing of 8 'bins'-four temporal and two spatial-from a heralded photon source. We show enhanced photon emission statistics, observing an increase in both the triggering and heralded photon rates. Despite its current limitations due to extrinsic sources of loss, this system points the way to harnessing temporal multiplexing in quantum technologies, from single-photon sources to large-scale computation.

  18. A Logical Temporal Relational Data Model

    E-Print Network [OSTI]

    Mahmood, Nadeem; Ahsan, Kamran

    2010-01-01T23:59:59.000Z

    Time is one of the most difficult aspects to handle in real world applications such as database systems. Relational database management systems proposed by Codd offer very little built-in query language support for temporal data management. The model itself incorporates neither the concept of time nor any theory of temporal semantics. Many temporal extensions of the relational model have been proposed and some of them are also implemented. This paper offers a brief introduction to temporal database research. We propose a conceptual model for handling time varying attributes in the relational database model with minimal temporal attributes.

  19. A Microfluidic Device for Temporally Controlled Gene Expression and Long-Term Fluorescent Imaging in

    E-Print Network [OSTI]

    Siggia, Eric

    A Microfluidic Device for Temporally Controlled Gene Expression and Long-Term Fluorescent Imaging of the cell cycle. Over the past ten years, microfluidic techniques in cell biology have emerged that allow a microfluidic flow cell to grow Saccharomyces Cerevisiae for more than 8 generations (

  20. Geomagnetic Temporal Spectrum Catherine Constable 1 GEOMAGNETIC TEMPORAL SPECTRUM

    E-Print Network [OSTI]

    Constable, Catherine G.

    of geomagnetic variations. The power spectral density S(f) is a measure of the power in geomagnetic field. At a distance of about 3 earth radii, the magnetospheric ring current for Encyclopedia of Geomagnetism measurements of the geomagnetic field to estimate the power spectrum. Power spectral estimation is usually

  1. Radiotherapy Adapted to Spatial and Temporal Variability in Tumor Hypoxia

    SciTech Connect (OSTI)

    Sovik, Aste [Department of Medical Physics, Norwegian Radium Hospital, Oslo (Norway); Department of Physics, University of Oslo, Oslo (Norway); Malinen, Eirik [Department of Medical Physics, Norwegian Radium Hospital, Oslo (Norway) and Department of Physics, University of Oslo, Oslo (Norway)]. E-mail: emalinen@fys.uio.no; Skogmo, Hege K. [Department of Companion Animal Clinical Sciences, Norwegian School of Veterinary Science, Oslo (Norway); Bentzen, Soren M. [Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin (United States); Bruland, Oyvind S. [Department of Oncology, Norwegian Radium Hospital, Oslo (Norway); Department of Clincal Medicine, University of Oslo, Oslo (Norway); Olsen, Dag Rune [Department of Physics, University of Oslo, Oslo (Norway); Department of Radiation Biology, Norwegian Radium Hospital, Oslo (Norway)

    2007-08-01T23:59:59.000Z

    Purpose: To explore the feasibility and clinical potential of adapting radiotherapy to temporal and spatial variations in tumor oxygenation. Methods and Materials: Repeated dynamic contrast enhanced magnetic resonance (DCEMR) images were taken of a canine sarcoma during the course of fractionated radiation therapy. The tumor contrast enhancement was assumed to represent the oxygen distribution. The IMRT plans were retrospectively adapted to the DCEMR images by employing tumor dose redistribution. Optimized nonuniform tumor dose distributions were calculated and compared with a uniform dose distribution delivering the same integral dose to the tumor. Clinical outcome was estimated from tumor control probability (TCP) and normal tissue complication probability (NTCP) modeling. Results: The biologically adapted treatment was found to give a substantial increase in TCP compared with conventional radiotherapy, even when only pretreatment images were used as basis for the treatment planning. The TCP was further increased by repeated replanning during the course of treatment, and replanning twice a week was found to give near optimal TCP. Random errors in patient positioning were found to give a small decrease in TCP, whereas systematic errors were found to reduce TCP substantially. NTCP for the adapted treatment was similar to or lower than for the conventional treatment, both for parallel and serial normal tissue structures. Conclusion: Biologically adapted radiotherapy is estimated to improve treatment outcome of tumors having spatial and temporal variations in radiosensitivity.

  2. Nano-elastohydrodynamics: Structure, dynamics, and flow in nonuniform lubricated junctions

    SciTech Connect (OSTI)

    Gao, J.; Luedtke, W.D.; Landman, U. [Georgia Institute of Technology, Atlanta, GA (United States)

    1995-10-27T23:59:59.000Z

    Structure, flow, and response characteristics of molecularly thin films of hexadecane, sheared by topographically nonuniform solid gold surfaces sliding at a relative velocity of 10 meters per second, were investigated with molecular dynamics simulations. The simulations reveal three characteristics: spatial and temporal variations in the density and pressure of the lubricant in the region confined by the approaching asperities, accompanied by asperity-induced molecular layering transitions that are reflected in oscillatory patterns in the friction force; asperity deformations and microstructural transformations mediated by the lubricant; and an onset of cavitated zones in the lubricant after the asperity-asperity collision process. The simulations extend micrometer-scale elastohydrodynamic investigations into the nanometer-scale regime and provide molecular-scale insights into the fundamental mechanisms of ultrathin film lubrication phenomena under extreme conditions. 20 refs., 3 figs.

  3. Time series of high resolution photospheric spectra in a quiet region of the Sun. II. Analysis of the variation of physical quantities of granular structures

    E-Print Network [OSTI]

    Puschmann, K G; Vazquez, M; Bonet, J A; Hanslmeier, A; 10.1051/0004-6361:20047193

    2012-01-01T23:59:59.000Z

    From the inversion of a time series of high resolution slit spectrograms obtained from the quiet sun, the spatial and temporal distribution of the thermodynamical quantities and the vertical flow velocity is derived as a function of logarithmic optical depth and geometrical height. Spatial coherence and phase shift analyzes between temperature and vertical velocity depict the height variation of these physical quantities for structures of different size. An average granular cell model is presented, showing the granule-intergranular lane stratification of temperature, vertical velocity, gas pressure and density as a function of logarithmic optical depth and geometrical height. Studies of a specific small and a specific large granular cell complement these results. A strong decay of the temperature fluctuations with increasing height together with a less efficient penetration of smaller cells is revealed. The T -T coherence at all granular scales is broken already at log tau =-1 or z~170 km. At the layers beyon...

  4. Self-regulating flow control device

    DOE Patents [OSTI]

    Humphreys, Duane A. (Pittsburgh, PA)

    1984-01-01T23:59:59.000Z

    A variable, self-regulating valve having a hydraulic loss coefficient proportional to a positive exponential power of the flow rate. The device includes two objects in a flow channel and structure which assures that the distance between the two objects is an increasing function of the flow rate. The range of spacing between the objects is such that the hydraulic resistance of the valve is an increasing function of the distance between the two objects so that the desired hydraulic loss coefficient as a function of flow rate is obtained without variation in the flow area.

  5. Variational symmetries, conserved quantities and identities for several equations of mathematical physics

    SciTech Connect (OSTI)

    Donchev, Veliko, E-mail: velikod@ie.bas.bg [Laboratory “Physical Problems of Electron and Ion Technologies,” Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko shosse, 1784 Sofia (Bulgaria)] [Laboratory “Physical Problems of Electron and Ion Technologies,” Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko shosse, 1784 Sofia (Bulgaria)

    2014-03-15T23:59:59.000Z

    We find variational symmetries, conserved quantities and identities for several equations: envelope equation, Böcher equation, the propagation of sound waves with losses, flow of a gas with losses, and the nonlinear Schrödinger equation with losses or gains, and an electro-magnetic interaction. Most of these equations do not have a variational description with the classical variational principle and we find such a description with the generalized variational principle of Herglotz.

  6. Structure of Turbulence in Katabatic Flows below and above the Wind-Speed Maximum

    E-Print Network [OSTI]

    Grachev, Andrey A; Di Sabatino, Silvana; Fernando, Harindra J S; Pardyjak, Eric R; Fairall, Christopher W

    2015-01-01T23:59:59.000Z

    Measurements of small-scale turbulence made over the complex-terrain atmospheric boundary layer during the MATERHORN Program are used to describe the structure of turbulence in katabatic flows. Turbulent and mean meteorological data were continuously measured at multiple levels at four towers deployed along the East lower slope (2-4 deg) of Granite Mountain. The multi-level observations made during a 30-day long MATERHORN-Fall field campaign in September-October 2012 allowed studying of temporal and spatial structure of katabatic flows in detail, and herein we report turbulence and their variations in katabatic winds. Observed vertical profiles show steep gradients near the surface, but in the layer above the slope jet the vertical variability is smaller. It is found that the vertical (normal to the slope) momentum flux and horizontal (along the slope) heat flux in a slope-following coordinate system change their sign below and above the wind maximum of a katabatic flow. The vertical momentum flux is directed...

  7. Nordic Journal of Computing TEMPORAL CONCURRENT CONSTRAINT

    E-Print Network [OSTI]

    Palamidessi, Catuscia

    Nordic Journal of Computing TEMPORAL CONCURRENT CONSTRAINT PROGRAMMING: DENOTATION, LOGIC on this semantics, we develop a proof system for linear­temporal properties of these processes. The expressiveness of ntcc is illustrated by modeling cells, timed systems such as RCX controllers, multi­agent systems

  8. Reasoning about Actions with Temporal Answer Sets

    E-Print Network [OSTI]

    Giordano, Laura; Dupré, Daniele Theseider

    2011-01-01T23:59:59.000Z

    In this paper we combine Answer Set Programming (ASP) with Dynamic Linear Time Temporal Logic (DLTL) to define a temporal logic programming language for reasoning about complex actions and infinite computations. DLTL extends propositional temporal logic of linear time with regular programs of propositional dynamic logic, which are used for indexing temporal modalities. The action language allows general DLTL formulas to be included in domain descriptions to constrain the space of possible extensions. We introduce a notion of Temporal Answer Set for domain descriptions, based on the usual notion of Answer Set. Also, we provide a translation of domain descriptions into standard ASP and we use Bounded Model Checking techniques for the verification of DLTL constraints.

  9. Flow chamber

    DOE Patents [OSTI]

    Morozov, Victor (Manassas, VA)

    2011-01-18T23:59:59.000Z

    A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

  10. Geological flows

    E-Print Network [OSTI]

    Yu. N. Bratkov

    2008-11-19T23:59:59.000Z

    In this paper geology and planetology are considered using new conceptual basis of high-speed flow dynamics. Recent photo technics allow to see all details of a flow, 'cause the flow is static during very short time interval. On the other hand, maps and images of many planets are accessible. Identity of geological flows and high-speed gas dynamics is demonstrated. There is another time scale, and no more. All results, as far as the concept, are new and belong to the author. No formulae, pictures only.

  11. Variational transition state theory

    SciTech Connect (OSTI)

    Truhlar, D.G. [Univ. of Minnesota, Minneapolis (United States)

    1993-12-01T23:59:59.000Z

    This research program involves the development of variational transition state theory (VTST) and semiclassical tunneling methods for the calculation of gas-phase reaction rates and selected applications. The applications are selected for their fundamental interest and/or their relevance to combustion.

  12. Temporal Discounting in Moral and Economic Judgement 

    E-Print Network [OSTI]

    Morton, David

    2013-01-01T23:59:59.000Z

    higher subjective valuations for sooner rewards relative to later ones, psychologists have proposed two competing models of temporal discounting: hyperbolic and exponential. In our study we presented a series of economic preference questions between a...

  13. The temporal efficiency of SO? emissions trading

    E-Print Network [OSTI]

    Ellerman, A. Denny

    2002-01-01T23:59:59.000Z

    This paper provides an empirical evaluation of the temporal efficiency of the U.S. Acid Rain Program, which implemented a nationwide market for trading and banking sulfur dioxide (SO2) emission allowances. We first develop ...

  14. A study of temporal visual composition

    E-Print Network [OSTI]

    Sun, Xiaohua, 1972-

    2007-01-01T23:59:59.000Z

    With the rapid growth of digital art, the temporal dimension is becoming a more and more important aspect of visual creations. This thesis is an effort to contribute to the construction of a disciplined basis for the ...

  15. Mdp Optimal Control under Temporal Logic Constraints

    E-Print Network [OSTI]

    Ding, Xu Chu

    In this paper, we develop a method to automatically generate a control policy for a dynamical system modeled as a Markov Decision Process (MDP). The control specification is given as a Linear Temporal Logic (LTL) formula ...

  16. Query Processing on Temporally Evolving Social Data

    E-Print Network [OSTI]

    Huo, Wenyu

    2013-01-01T23:59:59.000Z

    10 Figure 2: The TEG example and its nodes andefficient way, we use the Temporally Evolving Graph (TEG).In a TEG = (V, E, w, t s , t e ), besides the nodes, edges

  17. Agents, Beliefs, and Plausible Behavior in a Temporal Setting

    E-Print Network [OSTI]

    Zachmann, Gabriel

    Zachmann (Computer Graphics) #12;Agents, Beliefs, and Plausible Behavior in a Temporal Setting Nils Bulling

  18. Geospatio-temporal Semantic Web for Cultural Heritage Geospatio-temporal Semantic Web for Cultural

    E-Print Network [OSTI]

    Hyvönen, Eero

    that publish cultural heritage content on a map. For example, WatWasWaar.nl publishes historical geographicalGeospatio-temporal Semantic Web for Cultural Heritage Page 1 Geospatio-temporal Semantic Web for Cultural Heritage Tomi Kauppinen, Panu Paakkarinen, Eetu Mäkelä, Heini Kuittinen, Jari Väätäinen and Eero

  19. Porosity, Permeability, And Fluid Flow In The Yellowstone Geothermal...

    Open Energy Info (EERE)

    section of the 0.6-Ma Lava Creek ash-flow tuff. In this core, the degree of welding appears to be responsible for most of the variations in porosity, matrix...

  20. CFD analysis of laminar oscillating flows

    SciTech Connect (OSTI)

    Booten, C. W. Charles W.); Konecni, S. (Snezana); Smith, B. L. (Barton L.); Martin, R. A. (Richard A.)

    2001-01-01T23:59:59.000Z

    This paper describes a numerical simulations of oscillating flow in a constricted duct and compares the results with experimental and theoretical data. The numerical simulations were performed using the computational fluid dynamics (CFD) code CFX4.2. The numerical model simulates an experimental oscillating flow facility that was designed to test the properties and characteristics of oscillating flow in tapered ducts, also known as jet pumps. Jet pumps are useful devices in thermoacoustic machinery because they produce a secondary pressure that can counteract an unwanted effect called streaming, and significantly enhance engine efficiency. The simulations revealed that CFX could accurately model velocity, shear stress and pressure variations in laminar oscillating flow. The numerical results were compared to experimental data and theoretical predictions with varying success. The least accurate numerical results were obtained when laminar flow approached transition to turbulent flow.

  1. Spatial and temporal variation in fish assemblage structure at Village Creek

    E-Print Network [OSTI]

    Moriarty, Loren Joan

    1995-01-01T23:59:59.000Z

    . . . . . . . . . . . 50 22. Length frequency distributions mesohabitat and season. of Gambusia affinis by 59 23. Length frequency distributions mesohabitat and season. of Etheostoma vivax by . . 60 24. Length frequency distributions mesohabitat and season... COLLECTED AT VILLAGE CREEK, PRESENTED IN DESCENDING ORDER OF SITE OCCURRENCE. pecies ypnne a venusta Pimephales vigilax Gambusia affinis Fundulus olivaceus Notropis sabinae Notropis texanus Lepomis macrochirus Etheostoma vivax Labidesthes sicculus...

  2. SPATIAL AND TEMPORAL VARIATION IN CALCIUM AND ALUMINUM IN NORTHERN HARDWOOD FOREST FLOORS

    E-Print Network [OSTI]

    Phillips, Richard P.

    -6955) (Received 23 December 2003; accepted 22 July 2004) Abstract. Acid rain results in losses of exchangeable: acid rain, Ca:Al, cation depletion, forest floor, soil 1. Introduction Acid rain is thought to have and Simonsson, 2003). Alternatively, mobilization of Al by acid rain from the mineral soil below may provide

  3. DNA Microarray Data Clustering Based on Temporal Variation: FCV with TSD Preclustering

    E-Print Network [OSTI]

    Rostock, Universität

    artificial and real experimental data sets, where k-means and random clustering are used for comparison such as k-means or hierarchical clustering. The algorithm called fuzzy c- varieties clustering of the clusters; showing that the TSD-FCV algorithm has better performance than the k-means algorithm on both data

  4. Estimating permeability from quasi-static deformation: Temporal variations and arrival time inversion

    E-Print Network [OSTI]

    Vasco, D.W.

    2008-01-01T23:59:59.000Z

    Thermal Oper- ations and Heavy Oil Symposium, CHOA 97848,activity at the Cold Lake heavy oil ?eld, Alberta, Canada:

  5. Abstract--Meteorological time series are characterized by important spatial and temporal variation. Model determination and

    E-Print Network [OSTI]

    Fernandez, Thomas

    of the meteorological time series used, which includes the use of statistical techniques to detect whether there exist for the time series using an evolutionary algorithm that adaptively adjusts some of its parameters during its and temperatures collected in a region of Romania. The results are promising for the analysis of such time series

  6. Estimating permeability from quasi-static deformation: Temporal variations and arrival time inversion

    E-Print Network [OSTI]

    Vasco, D.W.

    2008-01-01T23:59:59.000Z

    eld, Algeria. The Krechba, Teg, and Reg are gas ?elds aredetermined for the Reg and Teg ?elds and observed throughout

  7. Temporal and spatial variation in methyl bromide emissions from a salt marsh 

    E-Print Network [OSTI]

    Drewer, Julia; Heal, Mathew R; Heal, Kate V; Smith, Keith A

    2006-01-01T23:59:59.000Z

    measurements of CH3Br emissions from a salt marsh in Scotland (56°00?N, 2°35?W) were made during one year using eight static enclosures. Net emissions showed both strong seasonal and diurnal cycles. Day-to-day maxima in emissions were associated with sunny days...

  8. Modeling temporal variations of electrical resistivity associated with pore pressure change in a kilometer-scale

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    (hautot@univ-brest.fr) [1] From 1995 to 1998 the natural electric field was monitored with an array of 20 role of fluids in the distortion of the induced electric fields. Electromagnetic methods could provide in a kilometer-scale natural system Sophie Hautot School of Geosciences, University of Edinburgh, Edinburgh, UK

  9. Supplementary Material Cover Sheet1 Temporal Variations of Organic Composition in the Tropical and Marine Atmosphere

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    's "Borneo: Treasure Island at Risk" Report (2005): http://www.mongabay.com/borneo.html). Mangroves are found

  10. Spatial and Temporal Variation in Stone Raw Material Provisioning in the Chivay Obsidian Source Area

    E-Print Network [OSTI]

    Tripcevich, Nicholas; MacKay, Alex

    2012-01-01T23:59:59.000Z

    we go: A llama caravan in Bolivia. Llama World Spring:10–15.Interaction in Peru and Bolivia LBL6343. Lawrence BerkeleyPeru and northern Bolivia. Journal of World Prehistory 14(

  11. Mortality experience of Tsimane amerindians of Bolivia: Regional variation and temporal trends

    E-Print Network [OSTI]

    Supa, Alfredo Zelada; Kaplan, Hillard; Gurven, Michael

    2007-01-01T23:59:59.000Z

    de adultos en el área rural de BoliviA (1829–1987). ArchivosAmerindians of Lowlands Bolivia [Ph.D. ]. Gainsville, FL:y originarios de Bolivia. Trinidad: Vice-Ministerio de

  12. "Method for Controlling of Spatial and Temporal Variations of Plasma

    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: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengtheningWildfiresImpurity

  13. Flow conditions of fresh mortar and concrete in different pipes

    SciTech Connect (OSTI)

    Jacobsen, Stefan, E-mail: stefan.jacobsen@ntnu.n [Norwegian University of Science and Technology, Dept of Structural Engineering, Trondheim (Norway); Haugan, Lars; Hammer, Tor Arne [SINTEF Byggforsk AS Building and Infrastructure, Trondheim (Norway); Kalogiannidis, Evangelos [Norwegian University of Science and Technology, Dept of Structural Engineering, Trondheim (Norway)

    2009-11-15T23:59:59.000Z

    The variation in fresh concrete flow rate over the pipe cross section was investigated on differently coloured and highly flowable concrete mixes flowing through pipes of different materials (rubber, steel, acryl). First, uncoloured (gray) concrete was poured through the pipe and the pipe blocked. Similar but coloured (black) concrete was then poured into the pipe filled with gray concrete, flowing after the gray concrete for a while before being blocked and hardened. The advance of the colouring along the pipe wall (showing boundary flow rate) was observed on the moulded concrete surface appearing after removing the pipe from the hardened concrete. The shapes of the interfaces between uncoloured and coloured concrete (showing variation of flow rate over the pipe cross section) were observed on sawn surfaces of concrete half cylinders cut along the length axes of the concrete-filled pipe. Flow profiles over the pipe cross section were clearly seen with maximum flow rates near the centre of the pipe and low flow rate at the pipe wall (typically rubber pipe with reference concrete without silica fume and/or stabilizers). More plug-shaped profiles, with long slip layers and less variation of flow rate over the cross section, were also seen (typically in smooth acrylic pipes). Flow rate, amount of concrete sticking to the wall after flow and SEM-images of pipe surface roughness were observed, illustrating the problem of testing full scale pumping.

  14. Inclusion of Inter-Temporal Constraints into a Distributed Newton-Raphson Method

    E-Print Network [OSTI]

    Li, Xin

    Power Flow (OPF) and Economic Dispatch (ED) are important components of the Energy Man- agement System (EMS) in electric power systems. Economic Dispatch is used to determine the most cost-effective gen in the economic dispatch problem. Another approach to overcome the variations in the power output of the renewable

  15. Downstream variations in the width of bedrock channels David R. Montgomery and Karen B. Gran

    E-Print Network [OSTI]

    Montgomery, David R.

    Downstream variations in the width of bedrock channels David R. Montgomery and Karen B. Gran the Mokelumne River show that bedrock channel width decreases substantially downstream at the contact between show systematic channel widening after flood flows and debris flow impacts. We conclude that downstream

  16. Heterogeneous Temporal Probabilistic Agents JURGEN DIX

    E-Print Network [OSTI]

    Kraus, Sarit

    and software modules. We will define the concept of a heterogeneous temporal probabilistic (HTP) agent). Intuitively, an FTPSI specifies what all an HTP agent is permitted/forbidden/obliged to do at various times t. As changes occur in the environment, the HTP agent must compute a new FTPSI. HTP agents continuously compute

  17. Temporal pulse tailoring in laser manufacturing technologies

    E-Print Network [OSTI]

    Peinke, Joachim

    5 Temporal pulse tailoring in laser manufacturing technologies Razvan Stoian1 , Matthias. Ultrafast lasers have gained momentum in material processing technolo- gies in response to requirements for quality material processing. 5.1 Introduction The demand for precision in laser material processing

  18. Issues in Temporal Representation of Multimedia Documents

    E-Print Network [OSTI]

    Joseph Fourier Grenoble-I, Université

    Issues in Temporal Representation of Multimedia Documents Nabil Layaïda OPERA project, INRIA Rhône the means of increasing the rich­ ness of information contained in electronic documents. One of the goals of the Opera team is designing an authoring environment for multimedia documents, called MADEUS, which meets

  19. Temporally Coherent Interactive Ray Tracing William Martin

    E-Print Network [OSTI]

    Utah, University of

    systems use a sparse sam- pling of the image (approximately one ray per pixel) and relatively small image in point sam- pled imagery by targeting new rays to intersection points from previous frames. Remaining to cause sub-pixel detail in rendered images, leading to temporal aliasing. We believe this is the dominant

  20. Spatiotemporal discrimination model predicts temporal masking functions

    E-Print Network [OSTI]

    CA 94035 a b Institute for Optical Research, Stockholm, Sweden W ABSTRACT e present a simplified dual, and masking based on local spatio­temporal contrast energy. The contras ensitivity filter parameters for the lack of space­time l s separability in contrast detection, the model has separate sustained

  1. Temporal Databases Status and Research Directions

    E-Print Network [OSTI]

    Snodgrass, Richard T.

    the other excellent papers in temporal databases. My goal is to characterize the evolution of this field relations when a DBMS can support multiple kinds of time. SIGMOD RECORD, Vol. 19, No. 4, December 1990 83-attribute-time-value quadruples) and implementation of the first historical DBMS, the Time Oriented Data

  2. Automated Storage Reclamation Using Temporal Importance Annotations

    E-Print Network [OSTI]

    Chandra, Surendar

    Automated Storage Reclamation Using Temporal Importance Annotations Surendar Chandra, Ashish.edu Abstract This work focuses on scenarios that require the storage of large amounts of data. Such sys- tems require the ability to either continuously increase the storage space or reclaim space by deleting

  3. Controlling Wild Bodies Using Linear Temporal Logic

    E-Print Network [OSTI]

    LaValle, Steven M.

    Controlling Wild Bodies Using Linear Temporal Logic Leonardo Bobadilla Oscar Sanchez Justin or state feedback. We do this by exploiting the wild motions of very simple bodies in an environment propose to start with a "wildly behaving" body for which its precise equations of motion are unknown

  4. SEISMIC INTERFEROMETRY FOR TEMPORAL MONITORING Norimitsu Nakata

    E-Print Network [OSTI]

    Snieder, Roel

    SEISMIC INTERFEROMETRY FOR TEMPORAL MONITORING by Norimitsu Nakata #12;c Copyright by Norimitsu Seismic interferometry, where one computes coherency of waves between two or more receivers and averages from the first study related to seismic interferometry (although the name of seismic interferometry has

  5. Enhancing Smart Home Algorithms Using Temporal Relations

    E-Print Network [OSTI]

    Cook, Diane J.

    Enhancing Smart Home Algorithms Using Temporal Relations Vikramaditya R. JAKKULA1 and Diane J COOK School of Electrical Engineering and Computer Science Abstract. Smart homes offer a potential benefit improves the performance of these algorithms and thus enhances the ability of smart homes to monitor

  6. DETECTION OF PLASMA FLUCTUATIONS IN WHITE-LIGHT IMAGES OF THE OUTER SOLAR CORONA: INVESTIGATION OF THE SPATIAL AND TEMPORAL EVOLUTION

    SciTech Connect (OSTI)

    Telloni, D.; Antonucci, E. [National Institute for Astrophysics (INAF), Astrophysical Observatory of Torino, Via Osservatorio 20, I-10025 Pino Torinese (Italy); Ventura, R.; Romano, P.; Spadaro, D. [National Institute for Astrophysics (INAF), Astrophysical Observatory of Catania, Via S. Sofia 78, I-95123 Catania (Italy)

    2013-04-20T23:59:59.000Z

    This work focuses on the first results from the identification and characterization of periodic plasma density fluctuations in the outer corona, observed in STEREO-A COR1 white-light image time series. A two-dimensional reconstruction of the spatial distribution and temporal evolution of the coronal fluctuation power has been performed over the whole plane of the sky, from 1.4 to 4.0 R{sub Sun }. The adopted diagnostic tool is based on wavelet transforms. This technique, with respect to the standard Fourier analysis, has the advantage of localizing non-persistent fluctuating features and exploring variations of the relating wavelet power in both space and time. The map of the variance of the coronal brightness clearly outlines intermittent spatially coherent fluctuating features, localized along, or adjacent to, the strongest magnetic field lines. In most cases, they do not correspond to the visible coronal structures in the brightness maps. The results obtained provide a scenario in which the solar corona shows quasi-periodic, non-stationary density variations characterized by a wide range of temporal and spatial scales and strongly confined by the magnetic field topology. In addition, structures fluctuating with larger power are larger in size and evolve more slowly. The characteristic periodicities of the fluctuations are comparable to their lifetimes. This suggests that plasma fluctuations lasting only one or two wave periods and initially characterized by a single dominant periodicity either rapidly decay into a turbulent mixed flow via nonlinear interactions with other plasma modes, or they are damped by thermal conduction. The periodic non-stationary coronal fluctuations outlined by the closed field lines at low and mid latitudes might be associated with the existence of slow standing magneto-acoustic waves excited by the convective supergranular motion. The fluctuating ray-like structures observed along open field lines appear to be linked either to the intermittent nature of the processes underlying the generation of magnetic reconnection in the polar regions or to the oscillatory transverse displacements of the coronal ray itself.

  7. Physiological Integration and Phenotypic Variation

    E-Print Network [OSTI]

    Arnold, Jonathan

    Physiological Integration and Phenotypic Variation in Vertebrates Seminar and Roundtable Guest Speaker: Lynn "Marty" Martin, PhD Assistant Professor Department of Integrative Biology, University

  8. Wavelet analysis of temporal data David Alexander Goodwin

    E-Print Network [OSTI]

    Stone, J. V.

    Wavelet analysis of temporal data David Alexander Goodwin Submitted in accordance proper acknowledgement. #12;i Abstract This thesis considers the application of wavelets to problems involving multiple series of temporal data. Wavelets have proven to be highly effective at extracting

  9. Evolution of transcription networks in response to temporal fluctuations

    E-Print Network [OSTI]

    Hespanha, João Pedro

    Evolution of transcription networks in response to temporal fluctuations Journal: Evolution, Evolution & Marine Biology Keywords: Population Genetics, Epistasis, Genetic Networks, Transcription Evolution: For Review Only #12;EVOLUTION OF TRANSCRIPTION NETWORKS IN RESPONSE TO TEMPORAL FLUCTUATIONS

  10. antibody encephalitis temporal: Topics by E-print Network

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

    Jon Reid 1987-01-01 57 Temporal Lorentzian Spectral Triples CERN Preprints Summary: We present the notion of temporal Lorentzian spectral triple which is an extension of the notion...

  11. aminocaproic acid temporal: Topics by E-print Network

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

    Jon Reid 1987-01-01 36 Temporal Lorentzian Spectral Triples CERN Preprints Summary: We present the notion of temporal Lorentzian spectral triple which is an extension of the notion...

  12. archival temporal bones: Topics by E-print Network

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

    13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Temporal Search Web Archives Computer Technologies and Information Sciences Websites Summary: Temporal...

  13. Viscous Flow Over a Chemically Patterned Surface

    E-Print Network [OSTI]

    J. E. Sprittles; Y. D. Shikhmurzaev

    2009-04-07T23:59:59.000Z

    The classical fluid dynamics boundary condition of no-slip suggests that variation in the wettability of a solid should not affect the flow of an adjacent liquid. However experiments and molecular dynamics simulations indicate that this is not the case. In this paper we show how flow over a solid substrate with variations of wettability can be described in a continuum framework using the interface formation theory developed earlier. Results demonstrate that a shear flow over a perfectly flat solid surface is disturbed by a change in its wettability, i.e. by a change in the chemistry of the solid substrate. The magnitude of the effect is shown to be proportional to cos(t1)-cos(t2) where t1 and t2 are the equilibrium contact angles that a liquid-gas free surface would form with the two chemically different parts of the solid surface.

  14. Global Representation of the Fine Structure Constant and its Variation

    E-Print Network [OSTI]

    Michael Edmund Tobar

    2005-02-06T23:59:59.000Z

    The fine structure constant, alpha, is shown to be proportional to the ratio of the quanta of electric and magnetic flux of force of the electron, and provides a new representation, which is global across all unit systems. Consequently, a variation in alpha was shown to manifest due to a differential change in the fraction of the quanta of electric and magnetic flux of force, while a variation in hcross.c was shown to manifest due to the common mode change. The representation is discussed with respect to the running of the fine structure constant at high energies (small distances), and a putative temporal drift. It is shown that the running of the fine structure constant is due to equal components of electric screening (polarization of vacuum) and magnetic anti-screening (magnetization of vacuum), which cause the perceived quanta of electric charge to increase at small distances, while the magnetic flux quanta decreases. This introduces the concept of the bare magnetic flux quanta as well as the bare electric charge. With regards to temporal drift, it is confirmed that it is impossible to determine which fundamental constant is varying if alpha varies.

  15. Solar weak currents, neutrino oscillations, and time variations

    SciTech Connect (OSTI)

    Haxton, W.C.; Zhang, W. (Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195 (USA) Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (USA))

    1991-04-15T23:59:59.000Z

    The effective neutrino mass in the presence of matter depends on both the charge and three-current weak densities. The effect of solar current loops on neutrino conversion need not be small if the scale of the eddies'' is comparable to the local oscillation length. This would seem to offer a mechanism for temporal variations in the neutrino flux that requires neither neutrino magnetic moments nor large solar density fluctuations. The effect of sinusoidally varying currents (or, alternatively, density fluctuations) is explored analytically and numerically. The analytic result we develop is based on the uniform approximation, and reduces to the adiabatic and Landau-Zener results in the appropriate limits. Despite the very interesting effects that may arise, we conclude that this mechanism for temporal variations in the solar-neutrino flux, like others suggested before, appears to require somewhat contrived solar conditions. However, it is quite likely that the influence of currents on neutrino effective masses is important and natural in other astrophysical settings, such as supernovas.

  16. Generating Descriptions that Summarize Geospatial and Temporal Data Martin Molina

    E-Print Network [OSTI]

    Molina, Martín

    pattern analysis, etc. In addition, geospatial and temporal data summarization can be combined with domainGenerating Descriptions that Summarize Geospatial and Temporal Data Martin Molina Department a knowledge-based method for automatically generating summaries of geospatial and temporal data, i.e. data

  17. PROTON: A Prolog Reasoner for Temporal ONtologies Nikos Papadakis1

    E-Print Network [OSTI]

    Petrakis, Euripides G.M.

    PROTON: A Prolog Reasoner for Temporal ONtologies in OWL Nikos Papadakis1 ,Kostas Stravoskoufos2, University of Crete, dp@csd.uoc.gr Abstract We present PROTON, a reasoner for managing temporal information. PROTON is implemented using this extension. Key words: Ramification problem; Temporal Ontologies

  18. A Foundation for Conventional and Temporal Query Optimization

    E-Print Network [OSTI]

    Snodgrass, Richard T.

    substantially from built-in temporal support in the DBMS. To achieve this, temporal query representation DBMS architectures and ones where the temporal support is obtained via a layer on top of a conventional DBMS. This foundation captures duplicates and ordering for all queries, as well as coalescing

  19. TEMPORAL PATTERN DISCOVERY FOR ANOMALY DETECTION IN A SMART HOME

    E-Print Network [OSTI]

    Cook, Diane J.

    TEMPORAL PATTERN DISCOVERY FOR ANOMALY DETECTION IN A SMART HOME Vikramaditya Jakkula , Diane J, cook}@eecs.wsu.edu Keywords: Knowledge discovery, smart homes, anomaly detection, temporal relations and relations on smart home datasets [10]. This paper describes a method of discovering temporal relations

  20. Spatial and Temporal Patterns of Global Onshore Wind Speed Distribution

    SciTech Connect (OSTI)

    Zhou, Yuyu; Smith, Steven J.

    2013-09-09T23:59:59.000Z

    Wind power, a renewable energy source, can play an important role in electrical energy generation. Information regarding wind energy potential is important both for energy related modeling and for decision-making in the policy community. While wind speed datasets with high spatial and temporal resolution are often ultimately used for detailed planning, simpler assumptions are often used in analysis work. An accurate representation of the wind speed frequency distribution is needed in order to properly characterize wind energy potential. Using a power density method, this study estimated global variation in wind parameters as fitted to a Weibull density function using NCEP/CFSR reanalysis data. The estimated Weibull distribution performs well in fitting the time series wind speed data at the global level according to R2, root mean square error, and power density error. The spatial, decadal, and seasonal patterns of wind speed distribution were then evaluated. We also analyzed the potential error in wind power estimation when a commonly assumed Rayleigh distribution (Weibull k = 2) is used. We find that the assumption of the same Weibull parameter across large regions can result in substantial errors. While large-scale wind speed data is often presented in the form of average wind speeds, these results highlight the need to also provide information on the wind speed distribution.

  1. variational method for rel ativistic

    E-Print Network [OSTI]

    on a rigourous variational meth od. Th is provides a numerical meth od wh ich is free of th e numerical drawbacks anics -- relativistic models for atoms and molecules -- computational meth ods -- ab­initio meth ods -- basis sets -- B­splines -- Dirac operators-- e#ective Hamiltonians -- variational meth ­ ods -- min

  2. Gunfire characterization and simulation using temporal moments

    SciTech Connect (OSTI)

    Smallwood, D.O.

    1994-08-01T23:59:59.000Z

    The concept of band-limited temporal moments is briefly reviewed. An input-output relationship for the band-limited product model is derived. The band-limited product model is then used to characterize and simulate a gunfire record in the following manner. An ensemble of 50 gunfire rounds are averaged to determine the mean response. The mean is subtracted from the original record and the remaining signal is characterized using a smoothed mean square response of the signal filtered into contiguous bandwidths. This operation preserves the lower bandlimited temporal moments of the original data. This smoothed mean square response was used as the deterministic window for the product model. The power spectrum of the response with the mean removed is used to estimate the spectrum for the random part a product model. An additional step varied the repetition rate in a random manner of the simulated gunfire rounds to match the original record in a statistical sense.

  3. Damage from pulses with arbitrary temporal shapes

    SciTech Connect (OSTI)

    Trenholme, J.B.

    1994-06-06T23:59:59.000Z

    In fusion laser designs, the laser pulse has a complicated temporal shape which undergoes significant change as it passes through the laser. Our damage data, however, was taken with pulses whose temporal shapes were (more or less) Gaussian. We want to determine the damage propensity of a material exposed to a pulse of arbitrary temporal shape , given data taken with Gaussian pulses of different pulse widths. To do so, we must adopt a physical model of damage. This model will contain some number of parameters that depend on material properties, geometry, and so forth. We determine the parameters of the model appropriate to each material by fitting the model to the Gaussian data for that material. The resulting normalized model is then applied, using the appropriate pulse shape, to find the damage level for a specific material subjected to a specific pulse. The model we shall assume is related to diffusion, although (as we shall see) the experimental results do not fit any simple diffusion model. Initially, we will discuss simple diffusion models. We then examine some experimental data, and then develop a modified diffusive model from that data. That modified model is then used to predict damage levels in various portions of the NIF laser design.

  4. Performance of the nested grid model during cold air outbreaks and periods of return flow

    E-Print Network [OSTI]

    Janish, Paul Richard

    1991-01-01T23:59:59.000Z

    the Return ot Wind and Geopotential Height Field Evolution 103 1) Offshore Flow Phase . . 2) Onshore Flow and the Low ? Level Jet. . . . 3) Extreme Case of 10-14 February 1988. . . . 105 117 126 7. REAL TIME VERIFICATION. . 132 a Satellite Data. b... and associated return flows are isolated. A good index of these cycles is the 950 mb meridional wind component. Composites and individual cases of the horizontal, vertical, and temporal structure of wind, temperature, and moisture are diagnosed for the NGM...

  5. Variational Principle of Hydrodynamics and Quantization by Stochastic Process

    E-Print Network [OSTI]

    T. Kodama; T. Koide

    2015-01-05T23:59:59.000Z

    The well-known hydrodynamical representation of the Schr\\"{o}dinger equation is reformulated by extending the idea of Nelson-Yasue's stochastic variational method. The fluid flow is composed by the two stochastic processes from the past and the future, which are unified naturally by the principle of maximum entropy. We show that this formulation is easily applicable to the quantization of scalar fields.

  6. Temporal evolution of multiple evaporating ribbon sources in a solar flare

    E-Print Network [OSTI]

    Graham, D R

    2015-01-01T23:59:59.000Z

    We present new results from the Interface Region Imaging Spectrograph showing the dynamic evolution of chromospheric evaporation and condensation in a flare ribbon, with the highest temporal and spatial resolution to date. IRIS observed the entire impulsive phase of the X-class flare SOL2014-09-10T17:45 using a 9.4 second cadence `sit-and-stare' mode. As the ribbon brightened successively at new positions along the slit, a unique impulsive phase evolution was observed for many tens of individual pixels in both coronal and chromospheric lines. Each activation of a new footpoint displays the same initial coronal up-flows of up to ~300 km/s, and chromospheric downflows up to 40 km/s. Although the coronal flows can be delayed by over 1 minute with respect to those in the chromosphere, the temporal evolution of flows is strikingly similar between all pixels, and consistent with predictions from hydrodynamic flare models. Given the large sample of independent footpoints, we conclude that each flaring pixel can be c...

  7. Determination of Transport Properties From Flowing Fluid Temperature LoggingIn Unsaturated Fractured Rocks: Theory And Semi-Analytical Solution

    SciTech Connect (OSTI)

    Mukhopadhyay, Sumit; Tsang, Yvonne W.

    2008-08-01T23:59:59.000Z

    Flowing fluid temperature logging (FFTL) has been recently proposed as a method to locate flowing fractures. We argue that FFTL, backed up by data from high-precision distributed temperature sensors, can be a useful tool in locating flowing fractures and in estimating the transport properties of unsaturated fractured rocks. We have developed the theoretical background needed to analyze data from FFTL. In this paper, we present a simplified conceptualization of FFTL in unsaturated fractured rock, and develop a semianalytical solution for spatial and temporal variations of pressure and temperature inside a borehole in response to an applied perturbation (pumping of air from the borehole). We compare the semi-analytical solution with predictions from the TOUGH2 numerical simulator. Based on the semi-analytical solution, we propose a method to estimate the permeability of the fracture continuum surrounding the borehole. Using this proposed method, we estimated the effective fracture continuum permeability of the unsaturated rock hosting the Drift Scale Test (DST) at Yucca Mountain, Nevada. Our estimate compares well with previous independent estimates for fracture permeability of the DST host rock. The conceptual model of FFTL presented in this paper is based on the assumptions of single-phase flow, convection-only heat transfer, and negligible change in system state of the rock formation. In a sequel paper [Mukhopadhyay et al., 2008], we extend the conceptual model to evaluate some of these assumptions. We also perform inverse modeling of FFTL data to estimate, in addition to permeability, other transport parameters (such as porosity and thermal conductivity) of unsaturated fractured rocks.

  8. An analysis of the trade-off between spatial and temporal resources for measurement-based quantum computation

    E-Print Network [OSTI]

    Jisho Miyazaki; Michal Hajdušek; Mio Murao

    2014-09-29T23:59:59.000Z

    In measurement-based quantum computation (MBQC), elementary quantum operations can be more parallelized than the quantum circuit model by employing a larger Hilbert space of graph states used as the resource. Thus MBQC can be regarded as a method of quantum computation where the temporal resource described by the depth of quantum operations can be reduced compared to the quantum circuit model by using the extra spatial resource described by graph states. To analyze the trade-off relationship of the spatial and temporal resources, we consider a method to obtain quantum circuit decompositions of general unitary transformations represented by MBQC on graph states with a certain underlying geometry called generalized flow. We present a method to translate any MBQC with generalized flow into quantum circuits without extra spatial resource. We also show an explicit way to unravel acausal gates that appear in the quantum circuit decomposition derived by a translation method presented in [V. Danos and E. Kashefi, Phys. Rev. A {\\bf 74}, 052310 (2006)] and that represent an effect of the reduction of the temporal resource in MBQC. Finally, by considering a way to deterministically simulate these acausal gates, we investigate a general framework to analyze the trade-off between the spacial and temporal resources for quantum computation.

  9. Quantization of systems with temporally varying discretization. I. Evolving Hilbert spaces

    SciTech Connect (OSTI)

    Höhn, Philipp A., E-mail: phoehn@perimeterinstitute.ca [Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo, Ontario N2L 2Y5 (Canada)

    2014-08-15T23:59:59.000Z

    A temporally varying discretization often features in discrete gravitational systems and appears in lattice field theory models subject to a coarse graining or refining dynamics. To better understand such discretization changing dynamics in the quantum theory, an according formalism for constrained variational discrete systems is constructed. While this paper focuses on global evolution moves and, for simplicity, restricts to flat configuration spaces R{sup N}, a Paper II [P. A. Höhn, “Quantization of systems with temporally varying discretization. II. Local evolution moves,” J. Math. Phys., e-print http://arxiv.org/abs/arXiv:1401.7731 [gr-qc].] discusses local evolution moves. In order to link the covariant and canonical picture, the dynamics of the quantum states is generated by propagators which satisfy the canonical constraints and are constructed using the action and group averaging projectors. This projector formalism offers a systematic method for tracing and regularizing divergences in the resulting state sums. Non-trivial coarse graining evolution moves lead to non-unitary, and thus irreversible, projections of physical Hilbert spaces and Dirac observables such that these concepts become evolution move dependent on temporally varying discretizations. The formalism is illustrated in a toy model mimicking a “creation from nothing.” Subtleties arising when applying such a formalism to quantum gravity models are discussed.

  10. Optical monitor for observing turbulent flow

    DOE Patents [OSTI]

    Albrecht, Georg F. (Livermore, CA); Moore, Thomas R. (Rochester, NY)

    1992-01-01T23:59:59.000Z

    The present invention provides an apparatus and method for non-invasively monitoring turbulent fluid flows including anisotropic flows. The present invention uses an optical technique to filter out the rays travelling in a straight line, while transmitting rays with turbulence induced fluctuations in time. The output is two dimensional, and can provide data regarding the spectral intensity distribution, or a view of the turbulence in real time. The optical monitor of the present invention comprises a laser that produces a coherent output beam that is directed through a fluid flow, which phase-modulates the beam. The beam is applied to a temporal filter that filters out the rays in the beam that are straight, while substantially transmitting the fluctuating, turbulence-induced rays. The temporal filter includes a lens and a photorefractive crystal such as BaTiO.sub.3 that is positioned in the converging section of the beam near the focal plane. An imaging system is used to observe the filtered beam. The imaging system may take a photograph, or it may include a real time camera that is connected to a computer. The present invention may be used for many purposes including research and design in aeronautics, hydrodynamics, and combustion.

  11. Low volume flow meter

    DOE Patents [OSTI]

    Meixler, Lewis D. (East Windsor, NJ)

    1993-01-01T23:59:59.000Z

    The low flow monitor provides a means for determining if a fluid flow meets a minimum threshold level of flow. The low flow monitor operates with a minimum of intrusion by the flow detection device into the flow. The electrical portion of the monitor is externally located with respect to the fluid stream which allows for repairs to the monitor without disrupting the flow. The electronics provide for the adjustment of the threshold level to meet the required conditions. The apparatus can be modified to provide an upper limit to the flow monitor by providing for a parallel electronic circuit which provides for a bracketing of the desired flow rate.

  12. Theory of solar luminosity variations

    E-Print Network [OSTI]

    H. C. Spruit

    2000-03-03T23:59:59.000Z

    The theory of stellar structure can be used to identify the most plausible mechanisms for the irradiance variations associated with the solar cycle. Changes in surface emissivity, i.e. the reduced cooling in spots and enhanced emission by small scale magnetic fields, are the most effective mechanisms and account for most of the observed variation. Helioseismology will soon be able to test the consequences of changes in surface emissivity, and distinguish them from other scenarios for irradiance variability.

  13. Attosecond Temporal Gating with Elliptically Polarized Light

    SciTech Connect (OSTI)

    Dudovich, N.; Smirnova, O.; Ivanov, M. Yu.; Villeneuve, D. M.; Corkum, P. B. [Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Levesque, J. [Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); INRS-EMT, 1650 boulevard Lionel-Boulet, CP 1020, Varennes, Quebec J3X 1S2 (Canada); Zeidler, D. [Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Carl Zeiss SMT AG, Oberkochen D-73447 (Germany); Comtois, D. [INRS-EMT, 1650 boulevard Lionel-Boulet, CP 1020, Varennes, Quebec J3X 1S2 (Canada)

    2006-12-22T23:59:59.000Z

    Temporal gating allows high accuracy time-resolved measurements of a broad range of ultrafast processes. By manipulating the interaction between an atom and an intense laser field, we extend gating into the nonlinear medium in which attosecond optical and electron pulses are generated. Our gate is an amplitude gate induced by ellipticity of the fundamental pulse. The gate modulates the spectrum of the high harmonic emission and we use the measured modulation to characterize the sub-laser-cycle dynamics of the recollision electron wave packet.

  14. Video sculpture:spatio-temporal warping

    E-Print Network [OSTI]

    Groves, Jeff David

    2004-09-30T23:59:59.000Z

    of Committee) Carol LaFayette (Member) John Keyser (Member) Phillip Tabb (Head of Department) December 2003 Major Subject: Visualization Sciences iii ABSTRACT Video Sculpture: Spatio-temporal Warping. (December 2003) Jeff Groves, B.S., Portland State University..., 2002. [22] J. Groves, Journeys in Space and Time. digital video, 2003. 35 VITA Jeff Groves 1402 Kirkwood Unit A Austin, TX 78722 jgroves@viz.tamu.edu Education M.S. in Visualization Sciences Texas A&M University, 12/03 B.S. in Architecture Portland...

  15. Bacteria in shear flow

    E-Print Network [OSTI]

    Marcos, Ph.D. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    Bacteria are ubiquitous and play a critical role in many contexts. Their environment is nearly always dynamic due to the prevalence of fluid flow: creeping flow in soil, highly sheared flow in bodily conduits, and turbulent ...

  16. Dispersed flow film boiling

    E-Print Network [OSTI]

    Yoder, Graydon L.

    1980-01-01T23:59:59.000Z

    Dispersed flow consists of small liquid droplets entrained in a flowing vapor. This flow regime can occur in cryogenic equipment, in steam generators, and during nuclear reactor loss of coolant accidents. A theoretical ...

  17. GSTP: A Temporal Reasoning System Supporting Multi-Granularity Temporal Constraints

    E-Print Network [OSTI]

    Mascetti, Sergio

    and algorithms proposed in the literature for Temporal Constraint Satisfaction Problems (TCSP) have essentially granularity, so that some of the standard algorithms for CSP, like consistency checking through arc- or path adopting these conversions as the only tool to reduce the problem to a standard CSP is in- evitably

  18. Implementing variation risk management during product development

    E-Print Network [OSTI]

    Padgalskas, Nicholas (Nicholas Keith)

    2007-01-01T23:59:59.000Z

    All manufactured systems exhibit some degree of variation. Manufacturing organizations should be aware of those parameters whose variation will impact product performance and customer satisfaction. Such parameters are ...

  19. Comparative Analysis of Proteome and Transcriptome Variation...

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

    Comparative Analysis of Proteome and Transcriptome Variation in Mouse. Comparative Analysis of Proteome and Transcriptome Variation in Mouse. Abstract: The relationships between...

  20. AA DiscretizationDiscretization ProcedureProcedure forfor EvolutionaryEvolutionary VariationalVariational

    E-Print Network [OSTI]

    Nagurney, Anna

    Variational InequalitiesInequalities andand ApplicationsApplications toto aa FinancialFinancial ModelModel Patrizia Daniele VariationalD Variational InequalitiesInequalities EE QuasiQuasi--VariationalVariational InequalitiesInequalitiesVariational InequalitiesInequalities"",, Comm.Comm. PurePure ApplAppl.. MathMath..,, 2222, 493, 493--519.519. 2.2. Brezis

  1. Multiphase flow calculation software

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2003-04-15T23:59:59.000Z

    Multiphase flow calculation software and computer-readable media carrying computer executable instructions for calculating liquid and gas phase mass flow rates of high void fraction multiphase flows. The multiphase flow calculation software employs various given, or experimentally determined, parameters in conjunction with a plurality of pressure differentials of a multiphase flow, preferably supplied by a differential pressure flowmeter or the like, to determine liquid and gas phase mass flow rates of the high void fraction multiphase flows. Embodiments of the multiphase flow calculation software are suitable for use in a variety of applications, including real-time management and control of an object system.

  2. analise temporal das: Topics by E-print Network

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

    Series IfI-07-11 12;Impressum Richter (Technical Computer Science) Prof. Dr. Gabriel Zachmann (Computer Graphics) 12;Markov Temporal of Markov chains and Markov decision...

  3. auditory temporal processing: Topics by E-print Network

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

    Websites Summary: properties of auditory-nerve (AN) fibers in normal and impaired ears. SPC manipulates the temporal aspects in the impaired ear. Quality judgments and...

  4. Penetrative turbulence associated with mesoscale surface heat flux variations

    E-Print Network [OSTI]

    Alam, Jahrul M

    2015-01-01T23:59:59.000Z

    This article investigates penetrative turbulence in the atmospheric boundary layer. Using a large eddy simulation approach, we study characteristics of the mixed layer with respect to surface heat flux variations in the range from 231.48 W/m$^2$ to 925.92 W/m$^2$, and observe that the surface heterogeneity on a spatial scale of $20$ km leads to downscale turbulent kinetic energy cascade. Coherent fluctuations of mesoscale horizontal wind is observed at 100m above the ground. Such a surface induced temporal oscillations in the horizontal wind suggest a rapid jump in mesocale wind forecasts, which is difficult to parameterize using traditional one-dimensional ensemble-mean models. Although the present work is idealized at a typical scale (20km) of surface heterogeneity, the results help develop effective subgrid scale parameterization schemes for classical weather forecasting mesoscale models.

  5. Precision electron flow measurements in a disk transmission line.

    SciTech Connect (OSTI)

    Clark, Waylon T.; Pelock, Michael D.; Martin, Jeremy Paul; Jackson, Daniel Peter Jr.; Savage, Mark Edward; Stoltzfus, Brian Scott; Mendel, Clifford Will, Jr.; Pointon, Timothy David

    2008-01-01T23:59:59.000Z

    An analytic model for electron flow in a system driving a fixed inductive load is described and evaluated with particle in cell simulations. The simple model allows determining the impedance profile for a magnetically insulated transmission line given the minimum gap desired, and the lumped inductance inside the transition to the minimum gap. The model allows specifying the relative electron flow along the power flow direction, including cases where the fractional electron flow decreases in the power flow direction. The electrons are able to return to the cathode because they gain energy from the temporally rising magnetic field. The simulations were done with small cell size to reduce numerical heating. An experiment to compare electron flow to the simulations was done. The measured electron flow is {approx}33% of the value from the simulations. The discrepancy is assumed to be due to a reversed electric field at the cathode because of the inductive load and falling electron drift velocity in the power flow direction. The simulations constrain the cathode electric field to zero, which gives the highest possible electron flow.

  6. Counterintuitive temporal shape of single photons

    E-Print Network [OSTI]

    Gurpreet Kaur Gulati; Bharath Srivathsan; Brenda Chng; Alessandro Cerè; Dzmitry Matsukevich; Christian Kurtsiefer

    2014-02-24T23:59:59.000Z

    We prepare heralded single photons from a photon pair source based on non-degenerate four-wave mixing in a cold atomic ensemble via a cascade decay scheme. Their statistics shows strong antibunching with g(2)(0) < 0.03, indicating a near single photon character. In an optical homodyne experiment, we directly measure the temporal envelope of these photons and find, depending on the heralding scheme, an exponentially decaying or rising profile. The rising envelope will be useful for efficient interaction between single photons and microscopic systems like single atoms and molecules. At the same time, their observation illustrates the breakdown of a realistic interpretation of the heralding process in terms of defining an initial condition of a physical system.

  7. Freshwater Flow Charts - 1995

    SciTech Connect (OSTI)

    Kaiper, G V

    2003-11-21T23:59:59.000Z

    This report covers the following: (1) Explanation of Charts Showing Freshwater Flow in 1995; (2) Estimated U.S. Freshwater Flow in 1995 (chart); (3) Estimated California Freshwater Flow in 1995 (chart); (4) Estimated New Mexico Freshwater Flow in 1995 (chart); and (5) Web locations and credits.

  8. Portable wastewater flow meter

    DOE Patents [OSTI]

    Hunter, Robert M. (320 S. Wilson Ave., Bozeman, MT 59715)

    1990-01-01T23:59:59.000Z

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under full pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  9. Portable wastewater flow meter

    DOE Patents [OSTI]

    Hunter, Robert M. (320 S. Wilson Ave., Bozeman, MT 59715)

    1999-02-02T23:59:59.000Z

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under fill pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  10. Regularization of Nonmonotone Variational Inequalities

    SciTech Connect (OSTI)

    Konnov, Igor V. [Department of Applied Mathematics, Kazan University, ul. Kremlevskaya 18, Kazan 420008 (Russian Federation)], E-mail: Igor.Konnov@ksu.ru; Ali, M.S.S. [Department of Mathematics, Faculty of Education, Ain Shams University, Cairo (Egypt); Mazurkevich, E.O. [Informatics Problems Institute of AS RT, Kazan 420012 (Russian Federation)

    2006-05-15T23:59:59.000Z

    In this paper we extend the Tikhonov-Browder regularization scheme from monotone to rather a general class of nonmonotone multivalued variational inequalities. We show that their convergence conditions hold for some classes of perfectly and nonperfectly competitive economic equilibrium problems.

  11. amygdala temporal dynamics: Topics by E-print Network

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

    amygdala temporal dynamics 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 TEMPORAL DYNAMICS OF BRAIN...

  12. analyze temporal dynamics: Topics by E-print Network

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

    analyze temporal dynamics 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 ATT: Analyzing Temporal...

  13. Temporal Logics for Concurrent Recursive Programs: Satisfiability and Model Checking

    E-Print Network [OSTI]

    Bollig, Benedikt

    Temporal Logics for Concurrent Recursive Programs: Satisfiability and Model Checking Benedikt,cyriac,gastin,zeitoun}@lsv.ens-cachan.fr Abstract. We develop a general framework for the design of temporal logics for concurrent recursive programs. A program execution is modeled as a partial order with multiple nesting relations. To specify

  14. TEMPORAL AND SPATIAL PREDICTION OF RADIOCAESIUM TRANSFER TO FOOD PRODUCTS

    E-Print Network [OSTI]

    Crout, Neil

    1 TEMPORAL AND SPATIAL PREDICTION OF RADIOCAESIUM TRANSFER TO FOOD PRODUCTS A.G. GILLETT1 , N #12;2 ABSTRACT A recently developed semi-mechanistic temporal model to is used predict food product (exchangeable K, pH, % clay and % organic matter content). A raster database of soil characteristics

  15. SALT---Structured Assertion Language for Temporal Logic

    E-Print Network [OSTI]

    Leucker, Martin

    SALT---Structured Assertion Language for Temporal Logic Andreas Bauer, Martin Leucker,leucker,streit}@informatik.tu­muenchen.de Abstract. This paper presents Salt. Salt is a general purpose speci­ fication and assertion language other formalisms used for temporal specification of properties, Salt does not target a specific domain

  16. SALT--Structured Assertion Language for Temporal Logic

    E-Print Network [OSTI]

    SALT--Structured Assertion Language for Temporal Logic Andreas Bauer, Martin Leucker , and Jonathan,leucker,streit}@informatik.tu-muenchen.de Abstract. This paper presents Salt. Salt is a general purpose speci- fication and assertion language other formalisms used for temporal specification of properties, Salt does not target a specific domain

  17. STQL --A SPATIO-TEMPORAL QUERY LANGUAGE Martin Erwig

    E-Print Network [OSTI]

    Erwig, Martin

    evolutions of spatial objects over time. We consider spatio- temporal operations that are particularly useful is to provide a DBMS data model and query language capable of handling such time-dependent geome- tries. Thereby. Our modeling also includes the sim- pler, discrete case where temporal evolutions are stepwise

  18. Adaptable Query Optimization and Evaluation in Temporal Middleware

    E-Print Network [OSTI]

    Snodgrass, Richard T.

    that such data- base applications may benefit substantially from built-in temporal support in the DBMS the DBMS proper or as a source level translation from temporal queries to conventional SQL. This paper proposes a new approach: using a middleware component on top of a conventional DBMS. This component accepts

  19. Representing a Robotic Domain Using Temporal Description Logics

    E-Print Network [OSTI]

    Franconi, Enrico

    Representing a Robotic Domain Using Temporal Description Logics Alessandro Artale artale@irst.itc effects; effects may not directly follow the action but more complex temporal relations may hold describes a collection of properties of the world holding at a certain time. Actions are represented through

  20. Constraint Orientated Specification with CSP and Real Time Temporal Logic

    E-Print Network [OSTI]

    Kent, University of

    Constraint Orientated Specification with CSP and Real Time Temporal Logic Justin Pearson Department Processes (CSP) [Hoa85] and a version of Propositional Temporal Logic (PTL), derived from [Eme90]. CSP. The behaviour of a CSP process is dependent on its environment; it is therefore difficult to assert global

  1. Temporal, Spatial, and Morphologic Features of Hair Cell Regeneration in

    E-Print Network [OSTI]

    Rubel, Edwin

    Temporal, Spatial, and Morphologic Features of Hair Cell Regeneration in the Avian Basilar Papilla 98195-7923 ABSTRACT Hair cell­selective antibodies were used in combination with the nucleotide bromode- oxyuridine (BrdU) to examine the temporal, spatial, and morphologic progression of auditory hair cell

  2. Land clearing reduces gene flow in the granite outcrop-dwelling lizard, Ctenophorus ornatus

    E-Print Network [OSTI]

    Tomkins, Joseph L.

    not provide adequate resources or protection from predation (Stow et al. 2001; Berry et al. 2005; Hoehn et al genetic variation as an indicator of levels of gene flow (e.g. Driscoll & Hardy 2005; Hoehn et al. 2007

  3. Stratum Approaches to Temporal DBMS Implementation Kristian Torp Christian S. Jensen

    E-Print Network [OSTI]

    Snodgrass, Richard T.

    Stratum Approaches to Temporal DBMS Implementation Kristian Torp Christian S. Jensen Department temporal DBMSs have assumed that a temporal DBMS must be built from scratch, employing an integrated a temporal DBMS as a stratum on top of an existing non-temporal DBMS, rendering implementation more feasible

  4. Infrastructure Analysis Tools: A Focus on Cash Flow Analysis (Presentation)

    SciTech Connect (OSTI)

    Melaina, M.; Penev, M.

    2012-09-01T23:59:59.000Z

    NREL has developed and maintains a variety of infrastructure analysis models for the U.S. Department of Energy. Business case analysis has recently been added to this tool set. This presentation focuses on cash flow analysis. Cash flows depend upon infrastructure costs, optimized spatially and temporally, and assumptions about financing and revenue. NREL has incorporated detailed metrics on financing and incentives into the models. Next steps in modeling include continuing to collect feedback on regional/local infrastructure development activities and 'roadmap' dynamics, and incorporating consumer preference assumptions on infrastructure to provide direct feedback between vehicles and station rollout.

  5. Anomalous diffusion for inertial particles under gravity in parallel flows

    E-Print Network [OSTI]

    Marco Martins Afonso

    2014-07-04T23:59:59.000Z

    We investigate the bounds between normal or anomalous effective diffusion for inertial particles transported by parallel flows. The infrared behavior of the fluid kinetic-energy spectrum, i.e. the possible presence of long-range spatio-temporal correlations, is modeled as a power law by means of two parameters, and the problem is studied as a function of these latter. Our results, obtained in the limit of weak relative inertia, extend well-known results for tracers and apply to particles of any mass density, subject to gravity and Brownian diffusion. We consider both steady and time-dependent flows, and cases of both vanishing and finite particle sedimentation.

  6. Weak-strong clustering transition in renewing compressible flows

    E-Print Network [OSTI]

    Ajinkya Dhanagare; Stefano Musacchio; Dario Vincenzi

    2014-11-01T23:59:59.000Z

    We investigate the statistical properties of Lagrangian tracers transported by a time-correlated compressible renewing flow. We show that the preferential sampling of the phase space performed by tracers yields significant differences between the Lagrangian statistics and its Eulerian counterpart. In particular, the effective compressibility experienced by tracers has a non-trivial dependence on the time correlation of the flow. We examine the consequence of this phenomenon on the clustering of tracers, focusing on the transition from the weak- to the strong-clustering regime. We find that the critical compressibility at which the transition occurs is minimum when the time correlation of the flow is of the order of the typical eddy turnover time. Further, we demonstrate that the clustering properties in time-correlated compressible flows are non-universal and are strongly influenced by the spatio-temporal structure of the velocity field.

  7. Weak-strong clustering transition in renewing compressible flows

    E-Print Network [OSTI]

    Dhanagare, Ajinkya; Vincenzi, Dario

    2014-01-01T23:59:59.000Z

    We investigate the statistical properties of Lagrangian tracers transported by a time-correlated compressible renewing flow. We show that the preferential sampling of the phase space performed by tracers yields significant differences between the Lagrangian statistics and its Eulerian counterpart. In particular, the effective compressibility experienced by tracers has a non-trivial dependence on the time correlation of the flow. We examine the consequence of this phenomenon on the clustering of tracers, focusing on the transition from the weak- to the strong-clustering regime. We find that the critical compressibility at which the transition occurs is minimum when the time correlation of the flow is of the order of the typical eddy turnover time. Further, we demonstrate that the clustering properties in time-correlated compressible flows are non-universal and are strongly influenced by the spatio-temporal structure of the velocity field.

  8. Two-phase air-water stratified flow measurement using ultrasonic techniques

    SciTech Connect (OSTI)

    Fan, Shiwei; Yan, Tinghu; Yeung, Hoi [School of Engineering, Cranfield University, Cranfield, Bedfordshire MK43 0AL (United Kingdom)

    2014-04-11T23:59:59.000Z

    In this paper, a time resolved ultrasound system was developed for investigating two-phase air-water stratified flow. The hardware of the system includes a pulsed wave transducer, a pulser/receiver, and a digital oscilloscope. The time domain cross correlation method is used to calculate the velocity profile along ultrasonic beam. The system is able to provide velocities with spatial resolution of around 1mm and the temporal resolution of 200?s. Experiments were carried out on single phase water flow and two-phase air-water stratified flow. For single phase water flow, the flow rates from ultrasound system were compared with those from electromagnetic flow (EM) meter, which showed good agreement. Then, the experiments were conducted on two-phase air-water stratified flow and the results were given. Compared with liquid height measurement from conductance probe, it indicated that the measured velocities were explainable.

  9. DNA Content Variation and Its Significance in the Evolution of the Genus Micrasterias (Desmidiales,

    E-Print Network [OSTI]

    in their evolutionary history. However, study of genome size variation in microalgae lags behind that of higher plants Micrasterias. We applied flow-cytometric techniques of DNA quantification to microalgae and mapped the importance of cell/life cycle studies for interpretation of DNA content measurements in microalgae. Citation

  10. Hydrodynamic forces and surface topography: Centimeter-scale spatial variation in wave forces

    E-Print Network [OSTI]

    Denny, Mark

    Hydrodynamic forces and surface topography: Centimeter-scale spatial variation in wave forces. On the rugose rock surfaces of wave-swept shores, interactions between substratum topography and wave-induced flow may create such a spatially variable environment. Topography Numerous investigators have explored

  11. Intracranial Pressure Variation Associated with Changes in End-Tidal CO2

    E-Print Network [OSTI]

    Intracranial Pressure Variation Associated with Changes in End-Tidal CO2 Sunghan Kim, James Mc that the partial pressure of arterial CO2 (PaCO2) can affect cerebral blood flow, cerebral blood volume, and therefore ICP. The end-tidal CO2 (ETCO2) is usually monitored by clinicians as a proxy for PaCO2. We show

  12. Variation of hydraulic conductance of some adult conifers under natural conditions

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Variation of hydraulic conductance of some adult conifers under natural conditions A. Granier, N; in the liquid phase, the flow depends upon water potential gradients and hydraulic conductance from the soil present here some evaluations of hydraulic conductance of trees growing under natural conditions. Data

  13. Scatterometer observations of wind variations induced by oceanic islands: Implications for

    E-Print Network [OSTI]

    Scatterometer observations of wind variations induced by oceanic islands: Implications for wind-driven of the Hawaiian and Cabo Verde islands on the mean atmospheric flow. A wake of weak winds, flanked by accelerated winds, appears for each major island of both archipelagos. The resulting wind stress curl displays

  14. Polarized quasiperiodic structures in pulsar radio emission reflect temporal modulations of non-stationary plasma flow

    E-Print Network [OSTI]

    Mitra, Dipanjan; Rankin, Joanna M

    2015-01-01T23:59:59.000Z

    Bright single pulses of many radio pulsars show rapid intensity fluctuations (called microstructure) when observed with time resolutions of tens of microseconds. Here, we report an analysis of Arecibo 59.5 $\\mu$sec-resolution polarimetric observations of 11 P-band and 32 L-band pulsars with periods ranging from 150 msec to 3.7 sec. These higher frequency observations forms the most reliable basis for detailed microstructure studies. Close inspection of individual pulses reveals that most pulses exhibit quasiperiodicities with a well-defined periodicity timescale ($P_{\\mu}$). While we find some pulses with deeply modulating microstructure, most pulses show low-amplitude modulations on top of broad smooth subpulses features, thereby making it difficult to infer periodicities. We have developed a method for such low-amplitude fluctuations wherein a smooth subpulse envelope is subtracted from each de-noised subpulse; the fluctuating portion of each subpulse is then used to estimate $P_{\\mu}$ via autocorrelation a...

  15. 113 Years of Physical Review: Using Flow Maps to Show Temporal and Topical Citation Patterns

    E-Print Network [OSTI]

    Indiana University

    Cyberinfrastructure for Network Science Center School of Library and Information Science, Indiana University. In 1977, the Physical Review introduced the Physics and Astronomy Classification Scheme (PACS) codes, revised, corrected and published; code(s) from the Physics and Astronomy Classification Scheme (PACS) [1

  16. Spatial and temporal analysis and experiments of annular two-phase flow under microgravity conditions

    E-Print Network [OSTI]

    Carron, Igor

    1992-01-01T23:59:59.000Z

    of the coexistence of huge waves with liquid slugs. This last observation however is already too detailed for the codes that are developed nowadays for nuclear safety assessment such as RELAP 5 [6). One of the main issue is therefore to characterize quantitatively... and base state II. 5 Verification of the code II. 6 Implementation . . II. 7 Conclusion 17 18 20 30 34 40 45 EXPERIMENTS IN A REDI. CED GRAVITY ENVIRONMENT . . III. l Experiments carried out at Texas A@i%'I University III. 2 The 1986 experiment...

  17. Professional Human Capital Flows: Temporal Structure of Loss, Replacement and Contingent Bundling Effects on Firm Performance

    E-Print Network [OSTI]

    Brymer, Rhett

    2012-10-19T23:59:59.000Z

    to appropriate more value than s/he brings to the new firm (Coff, _______________ This dissertation follows the style of Academy of Management Journal. 2 Pa ge 2 2011; 1999). Despite the evidence that losing and gaining PHC can negatively affect...

  18. Numerical integration of variational equations

    E-Print Network [OSTI]

    Ch. Skokos; E. Gerlach

    2010-09-29T23:59:59.000Z

    We present and compare different numerical schemes for the integration of the variational equations of autonomous Hamiltonian systems whose kinetic energy is quadratic in the generalized momenta and whose potential is a function of the generalized positions. We apply these techniques to Hamiltonian systems of various degrees of freedom, and investigate their efficiency in accurately reproducing well-known properties of chaos indicators like the Lyapunov Characteristic Exponents (LCEs) and the Generalized Alignment Indices (GALIs). We find that the best numerical performance is exhibited by the \\textit{`tangent map (TM) method'}, a scheme based on symplectic integration techniques which proves to be optimal in speed and accuracy. According to this method, a symplectic integrator is used to approximate the solution of the Hamilton's equations of motion by the repeated action of a symplectic map $S$, while the corresponding tangent map $TS$, is used for the integration of the variational equations. A simple and systematic technique to construct $TS$ is also presented.

  19. Oscillation Effects and Time Variation of the Supernova Neutrino Signal

    E-Print Network [OSTI]

    James P. Kneller; Gail C. McLaughlin; Justin Brockman

    2007-05-25T23:59:59.000Z

    The neutrinos detected from the next Galactic core-collapse supernova will contain valuable information on the internal dynamics of the explosion. One mechanism leading to a temporal evolution of the neutrino signal is the variation of the induced neutrino flavor mixing driven by changes in the density profile. With one and two dimensional hydrodynamical simulations we identify the behavior and properties of prominent features of the explosion. Using these results we demonstrate the time variation of the neutrino crossing probabilities due to changes in the MSW neutrino transformations as the star explodes by using the S-matrix - Monte Carlo - approach to neutrino propagation. After adopting spectra for the neutrinos emitted from the proto-neutron star we calculate for a Galactic supernova the evolution of the positron spectra within a water Cerenkov detector and the ratio of charged current to neutral current event rates for a heavy water - SNO like - detector and find that these detector signals are feasible probes of a number of explosion features.

  20. A NOVEL FLUID FLOW MODEL WITH MEMORY FOR POROUS MEDIA APPLICATIONS

    E-Print Network [OSTI]

    Hossain, M. Enamul

    thickness, rock and fluid properties independent of pressure and laminar flow are reported in many the rock and fluid properties to be constant in time. It is very important to consider the variation to consider the time variation of fluid and rock properties in a proper way. Therefore, Darcys law should

  1. Temporal condensed matter physics in gas-filled photonic crystal fibers

    E-Print Network [OSTI]

    Saleh, Mohammed F; Tran, Truong X; Marini, Andrea; Belli, Federico; Abdolvand, Amir; Biancalana, Fabio

    2014-01-01T23:59:59.000Z

    Raman effect in gases can generate an extremely long-living wave of coherence that can lead to the establishment of an almost perfect periodic variation of the medium refractive index. We show theoretically and numerically that the equations, regulate the pulse propagation in hollow-core photonic crystal fibers filled by Raman-active gas, are exactly identical to a classical problem in quantum condensed matter physics -- but with the role of space and time reversed -- namely an electron in a periodic potential subject to a constant electric field. We are therefore able to infer the existence of Wannier-Stark ladders, Bloch oscillations, and Zener tunneling, phenomena that are normally associated with condensed matter physics only, now realized with purely optical means in the temporal domain.

  2. Quantization of systems with temporally varying discretization I: Evolving Hilbert spaces

    E-Print Network [OSTI]

    Philipp A. Hoehn

    2014-10-02T23:59:59.000Z

    A temporally varying discretization often features in discrete gravitational systems and appears in lattice field theory models subject to a coarse graining or refining dynamics. To better understand such discretization changing dynamics in the quantum theory, an according formalism for constrained variational discrete systems is constructed. While the present manuscript focuses on global evolution moves and, for simplicity, restricts to Euclidean configuration spaces, a companion article discusses local evolution moves. In order to link the covariant and canonical picture, the dynamics of the quantum states is generated by propagators which satisfy the canonical constraints and are constructed using the action and group averaging projectors. This projector formalism offers a systematic method for tracing and regularizing divergences in the resulting state sums. Non-trivial coarse graining evolution moves lead to non-unitary, and thus irreversible, projections of physical Hilbert spaces and Dirac observables such that these concepts become evolution move dependent on temporally varying discretizations. The formalism is illustrated in a toy model mimicking a `creation from nothing'. Subtleties arising when applying such a formalism to quantum gravity models are discussed.

  3. Multi-region relaxed magnetohydrodynamics with anisotropy and flow

    SciTech Connect (OSTI)

    Dennis, G. R., E-mail: graham.dennis@anu.edu.au; Dewar, R. L.; Hole, M. J. [Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Hudson, S. R. [Princeton Plasma Physics Laboratory, PO Box 451, Princeton, New Jersey 08543 (United States)

    2014-07-15T23:59:59.000Z

    We present an extension of the multi-region relaxed magnetohydrodynamics (MRxMHD) equilibrium model that includes pressure anisotropy and general plasma flows. This anisotropic extension to our previous isotropic model is motivated by Sun and Finn's model of relaxed anisotropic magnetohydrodynamic equilibria. We prove that as the number of plasma regions becomes infinite, our anisotropic extension of MRxMHD reduces to anisotropic ideal MHD with flow. The continuously nested flux surface limit of our MRxMHD model is the first variational principle for anisotropic plasma equilibria with general flow fields.

  4. Ultrasonic flow metering system

    DOE Patents [OSTI]

    Gomm, Tyler J. (Meridian, ID); Kraft, Nancy C. (Idaho Falls, ID); Mauseth, Jason A. (Pocatello, ID); Phelps, Larry D. (Pocatello, ID); Taylor, Steven C. (Idaho Falls, ID)

    2002-01-01T23:59:59.000Z

    A system for determining the density, flow velocity, and mass flow of a fluid comprising at least one sing-around circuit that determines the velocity of a signal in the fluid and that is correlatable to a database for the fluid. A system for determining flow velocity uses two of the inventive circuits with directional transmitters and receivers, one of which is set at an angle to the direction of flow that is different from the others.

  5. Shallow soil CO2 flow along the San Andreas and Calaveras Faults, California

    E-Print Network [OSTI]

    Hilley, George

    Shallow soil CO2 flow along the San Andreas and Calaveras Faults, California J. L. Lewicki,1,2 W. C soil CO2 survey along the San Andreas fault (SAF) in Parkfield, and the Calaveras fault (CF) in Hollister, California, in the context of spatial and temporal variability, origin, and transport of CO2

  6. Under consideration for publication in J. Fluid Mech. 1 Analytical studies of flow effects due to

    E-Print Network [OSTI]

    Sen, Mihir

    and temporal behaviour of the specific boundary. Steady streaming induced by oscillatory flows over wavy of the wavy surface in comparison to the viscous boundary layer formed over the vibrating wall. Investigating boundaries is presented. A Newtonian viscous fluid confined in an infinite channel with flexible walls

  7. Relative permeability for two-phase flow through corrugated tubes as model porous media

    E-Print Network [OSTI]

    Feng, James J.

    -scale simulation, moving contact line, Cahn-Hilliard model, lubrication effect Corresponding author Email address of the solid wall, pore geometry, and the initial configuration. The effects of these factors are explored, for example. Finally, transient flows, such as occur in water- oil displacement, produce temporal and spatial

  8. Stochastic analysis of transient flow to a well in a heterogeneous aquifer

    E-Print Network [OSTI]

    Kurien, Susan

    of Arizona) Mentors: Shlomo P. Neuman (U of Arizona) Daniel Tartakovsky (LANL-T7) Introduction of potable water on Earth. The term groundwater is usually used to describe water that is beneath the water groundwater flow are generally uncertain in their exact nature, magnitude, and spatio- temporal distribution

  9. Genome size variation of Gossypium hirsutum 

    E-Print Network [OSTI]

    Gomez, Martha I.

    1993-01-01T23:59:59.000Z

    been found positively correlated with nuclear DNA content (Black and Bechmann, 1983). In Andropogon gerardii, 94% of the variation in DNA content could be explained on the basis of chromosome number (Keeler et al. , 1987). But variation in DNA...

  10. Glacier variations in the Bernese Alps (Switzerland)

    E-Print Network [OSTI]

    Steiner, Daniel

    Glacier variations in the Bernese Alps (Switzerland) ­ Reconstructions and simulations #12;#12;Glacier variations in the Bernese Alps (Switzerland) ­ Reconstructions and simulations Two Alpine glaciers over the last two centuries: a scientific view based on pictorial sources Starting

  11. Elbow mass flow meter

    DOE Patents [OSTI]

    McFarland, Andrew R. (College Station, TX); Rodgers, John C. (Santa Fe, NM); Ortiz, Carlos A. (Bryan, TX); Nelson, David C. (Santa Fe, NM)

    1994-01-01T23:59:59.000Z

    Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

  12. Border flow rights and Contracts for differences of differences

    E-Print Network [OSTI]

    Baldick, Ross

    marginal price for energy that it delivers to the rest of the system and pays the locational marginal price analogously to "contracts for differences" (CFDs) that are used to hedge locational marginal price variation implementation of the border flow rights model, the owner of a transmission line or lines is paid the locational

  13. Englacial phase changes and intergranular flow above subglacial lakes

    E-Print Network [OSTI]

    Rempel, Alan W.

    effects, and causes a decreasing transport rate near the base; hence, freezing occurs within as conduits for material transport. The density difference between water and ice produces a hydraulic gradient that drives liquid flow down towards the glacier bed. We investigate how variations in this transport rate

  14. Plio-Pleistocene time-averaged field in southern Patagonia recorded in lava flows

    E-Print Network [OSTI]

    Singer, Bradley S.

    Plio-Pleistocene time-averaged field in southern Patagonia recorded in lava flows V. Mejia and N. D of 53 lava flows from southern Patagonia (latitudes 49.5°­52.1°S) that include the Pali-Aike volcanic, 7 figures, 3 tables. Keywords: paleomagnetic secular variation; Patagonia; Pali-Aike Volcanic Field

  15. DYNAMIC SIMULATION OF THE TEMPORAL RESPONSE OF MICROSTRUCTURE FORMATION IN

    E-Print Network [OSTI]

    DYNAMIC SIMULATION OF THE TEMPORAL RESPONSE OF MICROSTRUCTURE FORMATION IN MAGNETORHEOLOGICAL in that the dielectric response of an ER fluid is studied in response to an electrical stimulus. These studies of MR

  16. Spatial and Temporal Dynamics of Salt Marsh Vegetation across Scales

    E-Print Network [OSTI]

    Kim, Daehyun

    2010-10-12T23:59:59.000Z

    Biogeographic patterns across a landscape are developed by the interplay of environmental processes operating at different spatial and temporal scales. This research investigated dynamics of salt marsh vegetation on the Skallingen salt marsh...

  17. Runtime Verification of Temporal Patterns for Dynamic Reconfigurations of Components

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , Olga Kouchnarenko1 , and Arnaud Lanoix2 1 University of Franche-Comté, Besançon, France {jdormoy Software - FACS 2011 (2011)" #12;In [14], we have proposed a temporal pattern logic, called FTPL, to char

  18. Using Temporal Logic for Dynamic Reconfigurations of Components

    E-Print Network [OSTI]

    Boyer, Edmond

    Using Temporal Logic for Dynamic Reconfigurations of Components Julien Dormoy1 , Olga Kouchnarenko1, published in "FACS 2010, 7th Int. Ws. on Formal Aspects of Component Software, Portugal (2010)" #12;More

  19. Using Temporal Logic for Dynamic Reconfigurations of Components

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Using Temporal Logic for Dynamic Reconfigurations of Components Julien Dormoy1 , Olga Kouchnarenko1, published in "7th International Workshop on Formal Aspects of Component Software - FACS'2010 (2010)" #12

  20. Psychophysical Indexes of Temporal Processing Abnormalities in Children

    E-Print Network [OSTI]

    Dougherty, Bob

    Psychophysical Indexes of Temporal Processing Abnormalities in Children With Developmental Dyslexia of Ophthalmology University of British Columbia, Canada Children with dyslexia and children progressing normally differen- tiate children with dyslexia from children with average reading abilities; (b) the ex- tent

  1. Cineplastic : temporal paradox in the movement-image medium

    E-Print Network [OSTI]

    Hanks, Travis W. (Travis Wesley)

    2006-01-01T23:59:59.000Z

    It could be argued that the term 'digital' as a prefix to architecture is evidence that contemporary design practice is lost in time. Modernity's predilection of spatial constructs over temporal ones continues to cast a ...

  2. accident temporal correlation: Topics by E-print Network

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

    In contrast, time-like separated measurements are only one-way no-signalling since the past is independent of the future but not vice-versa. For this reason temporal correlations...

  3. Process Abstraction in the Verification of Temporal Properties 

    E-Print Network [OSTI]

    Bruns, Glen R

    as abstraction operations. We show that an abstract process satisfies a property expressed as a temporal logic formula just if the original process satisfies a transformed formula. We define various abstraction operators and illustrate their use in verification...

  4. Lateral flow strip assay

    DOE Patents [OSTI]

    Miles, Robin R. (Danville, CA); Benett, William J. (Livermore, CA); Coleman, Matthew A. (Oakland, CA); Pearson, Francesca S. (Livermore, CA); Nasarabadi, Shanavaz L. (Livermore, CA)

    2011-03-08T23:59:59.000Z

    A lateral flow strip assay apparatus comprising a housing; a lateral flow strip in the housing, the lateral flow strip having a receiving portion; a sample collection unit; and a reagent reservoir. Saliva and/or buccal cells are collected from an individual using the sample collection unit. The sample collection unit is immersed in the reagent reservoir. The tip of the lateral flow strip is immersed in the reservoir and the reagent/sample mixture wicks up into the lateral flow strip to perform the assay.

  5. The spatial and temporal organization of soil moisture 

    E-Print Network [OSTI]

    Vogel, Gregor Klaus

    1995-01-01T23:59:59.000Z

    THE SPATIAL AND TEMPORAL ORGANIZATION OF SOIL MOISTURE A Thesis by GREGOR KLAUS VOGEL Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December... 1995 Major Subject: Water Resources Engineering THE SPATIAL AND TEMPORAL ORGANIZATION OF SOIL MOISTURE A Thesis by GREGOR KLAUS VOGEL Submitted to Texas ARM University in partial fulfillment of the requirements for the degree of MASTER...

  6. An Environmental Variation of Constants

    E-Print Network [OSTI]

    Philippe Brax

    2014-06-24T23:59:59.000Z

    Models of modified gravity, whereby local tests of gravity are evaded thanks to a screening mechanism of the chameleon or Damour-Polyakov types, lead to a spatial variation of the particle masses and the fine structure constant. This is triggered by the environmental dependence of the value of the scalar field whose presence modifies gravity. In dense media, the field settles at a density dependent value while in sparse environments it takes the background cosmological value. We estimate that the maximal deviation of constants from their present values is constrained by local tests of gravity, and must be less than $10^{-6}$.

  7. Compositional Variation Within Hybrid Nanostructures

    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: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting theCommercialization and Innovation2010Compositional Variation Within Hybrid

  8. Compositional Variation Within Hybrid Nanostructures

    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: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would like submit theInnovation Portal 50,904Compositional Variation

  9. Compositional Variation Within Hybrid Nanostructures

    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: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would like submit theInnovation PortalCompositional Variation Within

  10. Variational Approach for Fractional Partial Differential Equations

    E-Print Network [OSTI]

    Guo-cheng Wu

    2010-06-25T23:59:59.000Z

    Fractional variational approach has gained much attention in recent years. There are famous fractional derivatives such as Caputo derivative, Riesz derivative and Riemann-Liouville derivative. Several versions of fractional variational principles are proposed. However, it becomes difficult to apply the existing fractional variational theories to fractional differential models, due to the definitions of fractional variational derivatives which not only contain the left fractional derivatives but also appear right ones. In this paper, a new definition of fractional variational derivative is introduced by using a modified Riemann-Liouville derivative and the fractional Euler-Lagrange principle is established for fractional partial differential equations.

  11. THE INFLUENCE OF ENVIRONMENTAL FACTORS ON SPATIAL AND TEMPORAL VARIATION OF FISH ASSEMBLAGES IN THE LOWER BRAZOS RIVER, TEXAS

    E-Print Network [OSTI]

    LI, RAYMOND Y.

    -margin assemblage (Table 3). Other species commonly collected (relative abundance > 0.1%) along the river-margin were (in decreasing order of relative abundance) silverband shiner Notropis shumardi, mosquitofish Gambusia affinis, ghost shiner Notropis buchanani....172 Pimephales vigilax bullhead minnow Pim vig 723 237 103 1,879 166 1,518 4,626 16.398 Mugil cephalus striped mullet Mug cep 0 0 6 612 1 0 619 2.194 Gambusia affinis western mosquitofish Gam aff 359 173 732 71 21 39 1,395 4...

  12. Temporal and spatial variations of butyltin concentrations in bivalve and sediment samples from some coastal areas of the United States 

    E-Print Network [OSTI]

    Garcia-Romero, Bernardo

    1988-01-01T23:59:59.000Z

    ; THOMPSON et al. , 1985). However, in order to have an overall picture of the butyltin contamination, time-integrated water samplings of days or longer periods would be required (HUMPHREY and HOPE, 1987). HUGGETT et ak (1986) reported 9-98 ng Sn.... ) in sediments. Total butyltin concentrations ranged from &5 to 3760 (640 avg, ) and from &5 to 282 (36 avg. ) ng Sn/g dry weight in bivalve and sediment samples, respectively. Myri/us edulis (886 ng Sn/g) had higher average total butyltin concentrations than...

  13. Laboratory measurements of the temporal and cross-shore variation of the wave-induced bed stress

    E-Print Network [OSTI]

    Sukumaran, Ashok

    2000-01-01T23:59:59.000Z

    Detailed laboratory measurements of horizontal velocity above a rough, fixed, impermeable slope were made to determine the effect of varying wave conditions on the shear stress in the swash zone. The research involved the design, construction...

  14. Spatial and Temporal Variation in the Diet of Tree Swallows: Implications for Trace-Element Exposure After Habitat

    E-Print Network [OSTI]

    Hopkins, William A.

    to determine if trace elements from a recently remediated coal fly ash spill were moving into the terrestrial terrestrial habitats or industrial disposal practices that use water to dilute or hold contaminated materials

  15. Temporal and spatial distribution of the black-legged tick, Ixodes scapularis, in Texas and its association with climate variation

    E-Print Network [OSTI]

    Santelises, Joshua Steven

    2013-02-06T23:59:59.000Z

    in East Texas Pineywoods, Post Oak Savannah, and Blackland Prairies ecoregions. Trends in annual collections of I. scapularis in East Texas as an indicator of population change align with the periodicity and severity of drought when assessed against...

  16. Trophic ecology of the invasive argentine ant: spatio-temporal variation in resource assimilation and isotopic enrichment

    E-Print Network [OSTI]

    Menke, Sean B.; Suarez, Andy V.; Tillberg, Chadwick V.; Chou, Cheng T.; Holway, David A.

    2010-01-01T23:59:59.000Z

    colonies in circular plastic containers (28 cm in diameter)L pots) inside a larger plastic container (27 9 66 9 40 cm).

  17. Trophic ecology of the invasive argentine ant: spatio-temporal variation in resource assimilation and isotopic enrichment

    E-Print Network [OSTI]

    Menke, Sean B.; Suarez, Andy V.; Tillberg, Chadwick V.; Chou, Cheng T.; Holway, David A.

    2010-01-01T23:59:59.000Z

    assimilation and isotopic enrichment Sean B. Menke • Andy V.determined nitrogen enrichment using a controlled laboratoryconsumer- diet d15N enrichment: a meta-analysis. Oecologia

  18. Temporal variation of aerosol properties at a rural continental site and study of aerosol evolution through growth law analysis

    E-Print Network [OSTI]

    (direct effect) and by changing the microphysical structure, lifetime, and coverage of clouds (indirect effect). While it is widely accepted that aerosols could have significant impact on global climate, at present the magnitudes of these effects are poorly under- stood. Unlike greenhouse gases, whose radiative

  19. A Temporal Approach to Managing Schema Evolution in Object Database Systems

    E-Print Network [OSTI]

    Szafron, Duane

    A Temporal Approach to Managing Schema Evolution in Object Database Systems Iqbal A. Goralwalla,duane,ozsug@cs.ualberta.ca randal@cs.umanitoba.ca Abstract The issues of schema evolution and temporal object models are generally of a temporal object model. The result is a uniform treatment of schema evolution and temporal support for many

  20. Query Plans for Conventional and Temporal Queries Involving Duplicates and Ordering

    E-Print Network [OSTI]

    Snodgrass, Richard T.

    substantially from built- in temporal support in the DBMS. To achieve this, temporal query representation for providing temporal support both via a stand-alone temporal DBMS and via a layer on top of a conventional DBMS. By capturing duplicate removal and retention and order preservation for all queries, as well

  1. Cardiac C-arm computed tomography using a 3D + time ROI reconstruction method with spatial and temporal regularization

    SciTech Connect (OSTI)

    Mory, Cyril, E-mail: cyril.mory@philips.com [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, F-69621 Villeurbanne Cedex (France) [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, F-69621 Villeurbanne Cedex (France); Philips Research Medisys, 33 rue de Verdun, 92156 Suresnes (France); Auvray, Vincent; Zhang, Bo [Philips Research Medisys, 33 rue de Verdun, 92156 Suresnes (France)] [Philips Research Medisys, 33 rue de Verdun, 92156 Suresnes (France); Grass, Michael; Schäfer, Dirk [Philips Research, Röntgenstrasse 24–26, D-22335 Hamburg (Germany)] [Philips Research, Röntgenstrasse 24–26, D-22335 Hamburg (Germany); Chen, S. James; Carroll, John D. [Department of Medicine, Division of Cardiology, University of Colorado Denver, 12605 East 16th Avenue, Aurora, Colorado 80045 (United States)] [Department of Medicine, Division of Cardiology, University of Colorado Denver, 12605 East 16th Avenue, Aurora, Colorado 80045 (United States); Rit, Simon [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon (France) [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon (France); Université Lyon 1 (France); Centre Léon Bérard, 28 rue Laënnec, F-69373 Lyon (France); Peyrin, Françoise [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, F-69621 Villeurbanne Cedex (France) [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, F-69621 Villeurbanne Cedex (France); X-ray Imaging Group, European Synchrotron, Radiation Facility, BP 220, F-38043 Grenoble Cedex (France); Douek, Philippe; Boussel, Loïc [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon (France) [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon (France); Université Lyon 1 (France); Hospices Civils de Lyon, 28 Avenue du Doyen Jean Lépine, 69500 Bron (France)

    2014-02-15T23:59:59.000Z

    Purpose: Reconstruction of the beating heart in 3D + time in the catheter laboratory using only the available C-arm system would improve diagnosis, guidance, device sizing, and outcome control for intracardiac interventions, e.g., electrophysiology, valvular disease treatment, structural or congenital heart disease. To obtain such a reconstruction, the patient's electrocardiogram (ECG) must be recorded during the acquisition and used in the reconstruction. In this paper, the authors present a 4D reconstruction method aiming to reconstruct the heart from a single sweep 10 s acquisition. Methods: The authors introduce the 4D RecOnstructiOn using Spatial and TEmporal Regularization (short 4D ROOSTER) method, which reconstructs all cardiac phases at once, as a 3D + time volume. The algorithm alternates between a reconstruction step based on conjugate gradient and four regularization steps: enforcing positivity, averaging along time outside a motion mask that contains the heart and vessels, 3D spatial total variation minimization, and 1D temporal total variation minimization. Results: 4D ROOSTER recovers the different temporal representations of a moving Shepp and Logan phantom, and outperforms both ECG-gated simultaneous algebraic reconstruction technique and prior image constrained compressed sensing on a clinical case. It generates 3D + time reconstructions with sharp edges which can be used, for example, to estimate the patient's left ventricular ejection fraction. Conclusions: 4D ROOSTER can be applied for human cardiac C-arm CT, and potentially in other dynamic tomography areas. It can easily be adapted to other problems as regularization is decoupled from projection and back projection.

  2. Detecting Density Variations and Nanovoids

    SciTech Connect (OSTI)

    Miller, Michael K [ORNL; Longstreth-Spoor, L. [Washington University, St. Louis; Kelton, K. F. [Washington University, St. Louis

    2011-01-01T23:59:59.000Z

    A combination of simulated and experimental data has been used to investigate the size range of nanovoids that can be detected in atom probe tomography data. Simulated atom probe tomography data have revealed that nanovoids as small as 1 nm in diameter can be detected in atom probe tomography data with the use of iso-density surfaces. Iso-density surfaces may be used to quantify the size, morphology and number density of nanovoids and other variations in density in atom probe tomography data. Experimental data from an aluminum-yttrium-iron metallic glass ribbon have revealed the effectiveness of this approach. Combining iso-density surfaces with atom maps also permits the segregation of solute to the nanovoids to be investigated. Field ion microscopy and thin section atom maps have also been used to detect pores and larger voids.

  3. Numerical Study of Convective Heat Transfer in Flat Tube Heat Exchangers Operating in Self-Sustained Oscillatory Flow Regimes

    E-Print Network [OSTI]

    Fullerton, Tracy

    2012-02-14T23:59:59.000Z

    characterized by cyclic variations of flow parameters such as stream-wise or cross-stream velocity. A computer code was developed to perform the numerical simulations. Spatial discretization was based upon a Control Volume Finite Element Method (CVFEM...

  4. Variational methods for field theories

    SciTech Connect (OSTI)

    Ben-Menahem, S.

    1986-09-01T23:59:59.000Z

    Four field theory models are studied: Periodic Quantum Electrodynamics (PQED) in (2 + 1) dimensions, free scalar field theory in (1 + 1) dimensions, the Quantum XY model in (1 + 1) dimensions, and the (1 + 1) dimensional Ising model in a transverse magnetic field. The last three parts deal exclusively with variational methods; the PQED part involves mainly the path-integral approach. The PQED calculation results in a better understanding of the connection between electric confinement through monopole screening, and confinement through tunneling between degenerate vacua. This includes a better quantitative agreement for the string tensions in the two approaches. Free field theory is used as a laboratory for a new variational blocking-truncation approximation, in which the high-frequency modes in a block are truncated to wave functions that depend on the slower background modes (Boron-Oppenheimer approximation). This ''adiabatic truncation'' method gives very accurate results for ground-state energy density and correlation functions. Various adiabatic schemes, with one variable kept per site and then two variables per site, are used. For the XY model, several trial wave functions for the ground state are explored, with an emphasis on the periodic Gaussian. A connection is established with the vortex Coulomb gas of the Euclidean path integral approach. The approximations used are taken from the realms of statistical mechanics (mean field approximation, transfer-matrix methods) and of quantum mechanics (iterative blocking schemes). In developing blocking schemes based on continuous variables, problems due to the periodicity of the model were solved. Our results exhibit an order-disorder phase transition. The transfer-matrix method is used to find a good (non-blocking) trial ground state for the Ising model in a transverse magnetic field in (1 + 1) dimensions.

  5. Turbulent flow in graphene

    E-Print Network [OSTI]

    Kumar S. Gupta; Siddhartha Sen

    2010-06-05T23:59:59.000Z

    We demonstrate the possibility of a turbulent flow of electrons in graphene in the hydrodynamic region, by calculating the corresponding turbulent probability density function. This is used to calculate the contribution of the turbulent flow to the conductivity within a quantum Boltzmann approach. The dependence of the conductivity on the system parameters arising from the turbulent flow is very different from that due to scattering.

  6. Crisis bifurcations in plane Poiseuille flow

    E-Print Network [OSTI]

    Zammert, Stefan

    2015-01-01T23:59:59.000Z

    Direct numerical simulations of transitional plane Poiseuille flow in a mirror-symmetric subspace reveal several interior and exterior crisis bifurcations. They appear in the upper branch that emerges in a saddle-node bifurcation near $Re_{SN}=641$ and then undergoes several bifurcations into a chaotic attractor. Near $Re_{XC}=785.95$ the attractor collides with the lower-branch state and turns into a chaotic saddle in a exterior crisis, with a characteristic $(Re-Re_{XC})^{-\\delta}$ variation in lifetimes. For intermediate Reynolds numbers, the attractor undergoes several interior crises, in which new states appear and intermittent behavior can be observed. They contribute to increasing the complexity of the dynamics and to a more dense coverage of state space. The exterior crisis marks the onset of transient turbulence in this subspace of plane Poiseuille flow.

  7. Deformation of a flexible polymer in a random flow with long correlation time

    E-Print Network [OSTI]

    Stefano Musacchio; Dario Vincenzi

    2010-12-09T23:59:59.000Z

    The effects induced by long temporal correlations of the velocity gradients on the dynamics of a flexible polymer are investigated by means of theoretical and numerical analysis of the Hookean and FENE dumbbell models in a random renewing flow. For Hookean dumbbells, we show that long temporal correlations strongly suppress the Weissenberg-number dependence of the power-law tail characterising the probability density function (PDF) of the elongation. For the FENE model, the PDF becomes bimodal, and the coil-stretch transition occurs through the simultaneous drop and rise of the two peaks associated with the coiled and stretched configurations, respectively.

  8. A Holistic Framework for Environmental Flows Determination in Hydropower Contexts

    SciTech Connect (OSTI)

    McManamay, Ryan A [ORNL; Bevelhimer, Mark S [ORNL

    2013-05-01T23:59:59.000Z

    Among the ecological science community, the consensus view is that the natural flow regime sustains the ecological integrity of river systems. This prevailing viewpoint by many environmental stakeholders has progressively led to increased pressure on hydropower dam owners to change plant operations to affect downstream river flows with the intention of providing better conditions for aquatic biological communities. Identifying the neccessary magnitude, frequency, duration, timing, or rate of change of stream flows to meet ecological needs in a hydropower context is challenging because the ecological responses to changes in flows may not be fully known, there are usually a multitude of competing users of flow, and implementing environmental flows usually comes at a price to energy production. Realistically, hydropower managers must develop a reduced set of goals that provide the most benefit to the identified ecological needs. As a part of the Department of Energy (DOE) Water Power Program, the Instream Flow Project (IFP) was carried out by Oak Ridge National Laboratory (ORNL), Pacific Northwest National Laboratory (PNNL), and Argon National Laboratory (ANL) as an attempt to develop tools aimed at defining environmental flow needs for hydropower operations. The application of these tools ranges from national to site-specific scales; thus, the utility of each tool will depend on various phases of the environmental flow process. Given the complexity and sheer volume of applications used to determine environmentally acceptable flows for hydropower, a framework is needed to organize efforts into a staged process dependent upon spatial, temporal, and functional attributes. By far, the predominant domain for determining environmental flows related to hydropower is within the Federal Energy Regulatory Commission (FERC) relicensing process. This process can take multiple years and can be very expensive depending on the scale of each hydropower project. The utility of such a framework is that it can expedite the environmental flow process by 1) organizing data and applications to identify predictable relationships between flows and ecology, and 2) suggesting when and where tools should be used in the environmental flow process. In addition to regulatory procedures, a framework should also provide the coordination for a comprehensive research agenda to guide the science of environmental flows. This research program has further reaching benefits than just environmental flow determination by providing modeling applications, data, and geospatial layers to inform potential hydropower development. We address several objectives within this document that highlight the limitations of existing environmental flow paradigms and their applications to hydropower while presenting a new framework catered towards hydropower needs. Herein, we address the following objectives: 1) Provide a brief overview of the Natural Flow Regime paradigm and existing environmental flow frameworks that have been used to determine ecologically sensitive stream flows for hydropower operations. 2) Describe a new conceptual framework to aid in determining flows needed to meet ecological objectives with regard to hydropower operations. The framework is centralized around determining predictable relationships between flow and ecological responses. 3) Provide evidence of how efforts from ORNL, PNNL, and ANL have filled some of the gaps in this broader framework, and suggest how the framework can be used to set the stage for a research agenda for environmental flow.

  9. Optimization Online - Total variation superiorization schemes in ...

    E-Print Network [OSTI]

    S.N. Penfold

    2010-10-08T23:59:59.000Z

    Oct 8, 2010 ... Total variation superiorization schemes in proton computed tomography ... check improved the image quality, in particular image noise, in the ...

  10. Algorithms for Bilevel Pseudomonotone Variational Inequality ...

    E-Print Network [OSTI]

    2012-01-12T23:59:59.000Z

    Page 1 ... Variational innequality (shortlyVI) is a fundamental topic in applied mathematics. VIs are used for formulating and solving various problems arising in

  11. Mode spectrum and temporal soliton formation in optical microresonators

    E-Print Network [OSTI]

    Herr, T; Jost, J D; Mirgorodskiy, I; Lihachev, G; Gorodetsky, M L; Kippenberg, T J

    2013-01-01T23:59:59.000Z

    The formation of temporal dissipative solitons in optical microresonators enables compact, high repetition rate sources of ultra-short pulses as well as low noise, broadband optical frequency combs with smooth spectral envelopes. Here we study the influence of the resonator mode spectrum on temporal soliton formation. Using frequency comb assisted diode laser spectroscopy, the measured mode structure of crystalline MgF2 resonators are correlated with temporal soliton formation. While an overal general anomalous dispersion is required, it is found that higher order dispersion can be tolerated as long as it does not dominate the resonator's mode structure. Mode coupling induced avoided crossings in the resonator mode spectrum are found to prevent soliton formation, when affecting resonator modes close to the pump laser. The experimental observations are in excellent agreement with numerical simulations based on the nonlinear coupled mode equations, which reveal the rich interplay of mode crossings and soliton f...

  12. Microelectromechanical flow control apparatus

    DOE Patents [OSTI]

    Okandan, Murat (NE Albuquerque, NM)

    2009-06-02T23:59:59.000Z

    A microelectromechanical (MEM) flow control apparatus is disclosed which includes a fluid channel formed on a substrate from a first layer of a nonconducting material (e.g. silicon nitride). A first electrode is provided on the first layer of the nonconducting material outside the flow channel; and a second electrode is located on a second layer of the nonconducting material above the first layer. A voltage applied between the first and second electrodes deforms the fluid channel to increase its cross-sectional size and thereby increase a flow of a fluid through the channel. In certain embodiments of the present invention, the fluid flow can be decreased or stopped by applying a voltage between the first electrode and the substrate. A peristaltic pumping of the fluid through the channel is also possible when the voltage is applied in turn between a plurality of first electrodes and the substrate. A MEM flow control assembly can also be formed by providing one or more MEM flow control devices on a common substrate together with a submicron filter. The MEM flow control assembly can optionally include a plurality of pressure sensors for monitoring fluid pressure and determining flow rates through the assembly.

  13. Systems for controlling the intensity variations in a laser beam and for frequency conversion thereof

    DOE Patents [OSTI]

    Skupsky, S.; Craxton, R.S.; Soures, J.

    1990-10-02T23:59:59.000Z

    In order to control the intensity of a laser beam so that its intensity varies uniformly and provides uniform illumination of a target, such as a laser fusion target, a broad bandwidth laser pulse is spectrally dispersed spatially so that the frequency components thereof are spread apart. A disperser (grating) provides an output beam which varies spatially in wavelength in at least one direction transverse to the direction of propagation of the beam. Temporal spread (time delay) across the beam is corrected by using a phase delay device (a time delay compensation echelon). The dispersed beam may be amplified with laser amplifiers and frequency converted (doubled, tripled or quadrupled in frequency) with nonlinear optical elements (birefringent crystals). The spectral variation across the beam is compensated by varying the angle of incidence on one of the crystals with respect to the crystal optical axis utilizing a lens which diverges the beam. Another lens after the frequency converter may be used to recollimate the beam. The frequency converted beam is recombined so that portions of different frequency interfere and, unlike interference between waves of the same wavelength, there results an intensity pattern with rapid temporal oscillations which average out rapidly in time thereby producing uniform illumination on target. A distributed phase plate (also known as a random phase mask), through which the spectrally dispersed beam is passed and then focused on a target, is used to provide the interference pattern which becomes nearly modulation free and uniform in intensity in the direction of the spectral variation. 16 figs.

  14. Composition Pulse Time-Of-Flight Mass Flow Sensor

    DOE Patents [OSTI]

    Mosier, Bruce P. (San Francisco, CA); Crocker, Robert W. (Fremont, CA); Harnett, Cindy K. (Livermore, CA) l

    2004-01-13T23:59:59.000Z

    A device for measuring fluid flow rates over a wide range of flow rates (<1 nL/min to >10 .mu.L/min) and at pressures at least as great as 10,000 psi. The invention is particularly adapted for use in microfluidic systems. The device operates by producing compositional variations in the fluid, or pulses, that are subsequently detected downstream from the point of creation to derive a flow rate. Each pulse, comprising a small fluid volume, whose composition is different from the mean composition of the fluid, can be created by electrochemical means, such as by electrolysis of a solvent, electrolysis of a dissolved species, or electrodialysis of a dissolved ionic species. Measurements of the conductivity of the fluid can be used to detect the arrival time of the pulses, from which the fluid flow rate can be determined

  15. Plasma flow at a high Mach-number

    SciTech Connect (OSTI)

    Yu, Bing; Hameiri, Eliezer [Courant Institute of Mathematical Sciences, New York University New York, New York 10012 (United States)] [Courant Institute of Mathematical Sciences, New York University New York, New York 10012 (United States)

    2013-09-15T23:59:59.000Z

    Unlike the case of static magnetohydrodynamic (MHD) equilibria, where an expansion in large aspect ratio of toroidal devices is common, cases of MHD equilibria with flow are rarely treated this way, and when this is done the expansion tends to be only partial. The main reason for the difference seems to be the difficulty of expanding the larger system of equilibrium equations with flow. Here, we use a recent expansion technique which employs a variational principle to simplify the process [E. Hameiri, Phys. Plasmas 20, 024504 (2013)]. We treat four cases of MHD equilibria with flow, developing their asymptotic expansions in full, and for an application consider the effect of the flow on the Shafranov shift.

  16. Generating Beta Variates Via Patchwork Rejection \\Lambda

    E-Print Network [OSTI]

    Stadlober, Ernst

    Generating Beta Variates Via Patchwork Rejection \\Lambda H. Zechner and E. Stadlober, Graz --- Zusammenfassung Generating Beta Variates Via Patchwork Rejection. A new algorithm for sampling from beta(p; q deviates can often be accepted immediately, so that much fewer than two uniforms are needed for one beta

  17. A Fitting Robot for Variational Analysis

    E-Print Network [OSTI]

    Alan Ó Cais; Derek Leinweber; Selim Mahbub; Tony Williams

    2008-12-18T23:59:59.000Z

    We develop a robot algorithm to maximise the number of distinct states reliably extracted from correlator data using the variational analysis method. The robot explores the variational parameter space and attempts to remove, as far as possible, the human element from the fitting of the subsequent orthogonalised data.

  18. Variational inference for Dirichlet process mixtures

    E-Print Network [OSTI]

    Sekhon, Jasjeet S.

    Variational inference for Dirichlet process mixtures David M. Blei School of Computer Science Carnegie-Mellon University blei@cs.cmu.edu Michael I. Jordan Computer Science Division and Department, 2001; Blei et al., 2003). In this paper, we present a variational inference algo- rithm for DP mixtures

  19. Nucleotide Frequency Variation Across Human Genes

    E-Print Network [OSTI]

    Majewski, Jacek

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

  20. A Variational Formulation of Kinematic Waves 1 A VARIATIONAL FORMULATION OF

    E-Print Network [OSTI]

    Daganzo, Carlos F.

    A Variational Formulation of Kinematic Waves 1 A VARIATIONAL FORMULATION OF KINEMATIC WAVES proposes two algorithms that, based on a variational version of kinematic wave (KW) theory (Daganzo, 2003, University of California, Berkeley, California, USA ABSTRACT It has been recently shown that all kinematic

  1. An SF6 Tracer Study of the Flow Dynamics in the Stockton Deep Water Ship Channel: Implications

    E-Print Network [OSTI]

    Ho, David

    An SF6 Tracer Study of the Flow Dynamics in the Stockton Deep Water Ship Channel: Implications) to quantify mixing and transport rates. SF6 was injected in the San Joaquin River upstream of the DWSC and mapped for 8 days. From the temporal change in SF6 distributions, the longitudinal dispersion coefficient

  2. Magnetically stimulated fluid flow patterns

    ScienceCinema (OSTI)

    Martin, Jim; Solis, Kyle

    2014-08-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  3. Magnetically stimulated fluid flow patterns

    SciTech Connect (OSTI)

    Martin, Jim; Solis, Kyle

    2014-03-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  4. Dynamics of wrinkles on a vesicle in external flow

    E-Print Network [OSTI]

    K. S. Turitsyn; S. S. Vergeles

    2007-05-24T23:59:59.000Z

    Recent experiments by Kantsler et. al. (2007) have shown that the relaxational dynamics of a vesicle in external elongation flow is accompanied by the formation of wrinkles on a membrane. Motivated by these experiments we present a theory describing the dynamics of a wrinkled membrane. Formation of wrinkles is related to the dynamical instability induced by negative surface tension of the membrane. For quasi-spherical vesicles we perform analytical study of the wrinkle structure dynamics. We derive the expression for the instability threshold and identify three stages of the dynamics. The scaling laws for the temporal evolution of wrinkling wavelength and surface tension are established and confirmed numerically.

  5. Experimental and theoretical studies of the effects of nonuniformities in nonequilibrium magnetohydrodynamic flows

    SciTech Connect (OSTI)

    Lytle, J.K.; Louis, J.F.

    1984-07-01T23:59:59.000Z

    A study of wake nonuniformities in a nonequilibrium magnetohydrodynamic plasma is described. Experimental results are presented from an electrodeless disk-shaped channel in both radial flow and swirl flow configurations. The experimental conditions are analyzed with a nonequilibrium plasma model that accounts for variations in the wake gas properties and wake width. The results show that the wake nonuniformities in the radial flow channel are weak, but in the swirl flow channel they are strong because of an instability. This instability is a consequence of the wake orientation. Furthermore, the intensity of the nonuniformity in an unstable plasma is dependent upon the wake gas velocity and wake width.

  6. Investigation of flow in vane-island diffusers in centrifugal compressors 

    E-Print Network [OSTI]

    Vandijk, Hanne Nicolaas

    1976-01-01T23:59:59.000Z

    Boundary slope variation along the channel 46 US. Pressure recovery coefficient (B;1 Pressure Ratio) 31 Uaned diffuser geometry 53 ix NOMENCLATURE ~Smbo1 ~tl i ti A, B, C Cf Constants Vane height Coefficient of friction Cp Pressure recovery (with... Flow reOions of the vaned diffuser because the flow path changes from a rotating system into a stationary system. This complex unsteady flow is strongly affected by the jet-wake flow [1] leaving the impeller, Fig. 4, the three-dimensional boundary...

  7. Blind source separation using spatial and temporal priors

    E-Print Network [OSTI]

    Roberts, Stephen

    #12;Blind source separation using spatial and temporal priors W D Addison Balliol University of Oxford A thesis submitted for the degree of Doctor of Philosophy Trinity 2009 2 #12;3 #12 for providing such fine accommodation in Oxford and to my wife for her incredible patience while this thesis

  8. TEMPORAL PERFORMANCE EVALUATION OF CONTROL ARCHITECTURE IN AUTOMATION

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    TEMPORAL PERFORMANCE EVALUATION OF CONTROL ARCHITECTURE IN AUTOMATION SYSTEMS Pascal Meunier, Bruno, France pascal.meunier@lurpa.ens-cachan.fr (Pascal Meunier) Abstract The performances of automation performances of networked automation system and which guides the engineer throughout the control architecture

  9. The Post Anachronism: The Temporal Dimension of Facebook Privacy

    E-Print Network [OSTI]

    Reiter, Michael

    The Post Anachronism: The Temporal Dimension of Facebook Privacy Lujo Bauer , Lorrie Faith Cranor the audience and emphasis of Facebook posts change over time. In a 63-participant longitudinal study, par- ticipants gave their audience and emphasis preferences for up to ten of their Facebook posts in the week

  10. An Approximate Inference Approach to Temporal Optimization in Optimal Control

    E-Print Network [OSTI]

    Vijayakumar, Sethu

    on iterative local approximations present a practical approach to optimal control in robotic systems. However the optimal control framework. The proposed approach, which is applicable to plants with non-linear dynamicsAn Approximate Inference Approach to Temporal Optimization in Optimal Control Konrad C. Rawlik

  11. Spatio-Temporal Signal Recovery from Political Tweets in Indonesia

    E-Print Network [OSTI]

    Davulcu, Hasan

    Spatio-Temporal Signal Recovery from Political Tweets in Indonesia Anisha Mazumder, Arun Das activity in the provinces of Indonesia. Based on analysis of radical/counter radical sentiments expressed in tweets by Twitter users, we create a Heat Map of Indonesia which visually demonstrates the degree

  12. Temporal Changes in a Tropical Nekton Assemblage and

    E-Print Network [OSTI]

    Temporal Changes in a Tropical Nekton Assemblage and Performance of a Prawn Selective Gear TING and weights of 39 trials conductedfor a selective prawning gear whose performance in bycatch reduc tionI., 1975; Rob erts, 1978; Allen and Coates, 1990), but is extremely rich in the marine coun terpart

  13. A Spatio-Temporal Point Process Model for Ambulance Demand

    E-Print Network [OSTI]

    Woodard, Dawn B.

    (EMS) managers need accurate demand estimates to mini- mize response times to emergencies and keep. Several studies have modeled aggregate ambulance demand as a temporal process. Channouf et al. (2007) use by combining a dynamic latent factor structure with integer time series models. Other aggregate demand studies

  14. A qualitative model for temporal reasoning with incomplete information

    SciTech Connect (OSTI)

    Geffner, H. [Universidad Simon Bolivar, Caracas (Venezuela)

    1996-12-31T23:59:59.000Z

    We develop a qualitative framework for temporal reasoning with incomplete information that features a modeling language based on rules and a semantics based on infinitesimal probabilities. The framework relates logical and probabilistical models, and accommodates in a natural way features that have been found problematic in other models like non-determinism, action qualifications, parallel actions, and abduction to actions and fluents.

  15. Distributed Temporal Logic for the Analysis of Security Protocol Models

    E-Print Network [OSTI]

    Basin, David

    , showing that it is sufficient to consider models in which the intruder completely controls the networkDistributed Temporal Logic for the Analysis of Security Protocol Models David Basin Department to reason about and relate different security-protocol models. This includes reasoning about model

  16. JournalofCellScience ERK and phosphoinositide 3-kinase temporally

    E-Print Network [OSTI]

    Amaya, Enrique

    JournalofCellScience ERK and phosphoinositide 3-kinase temporally coordinate different modes and distinct downstream targets. The sequential activation of ERK and phosphoinositide 3-kinase (PI3K) signalling divides Xenopus embryonic wound healing into two phases. In the first phase, activated ERK

  17. Bayesian spatio-temporal modelling for inspection and

    E-Print Network [OSTI]

    Little, John

    of potential applications for these models, for example, a single oil refining plant may inspect thousands in the petrochemical industry John Little A thesis presented for the degree of Doctor of Philosophy Statistics Group-temporal modelling for inspection and prediction of complex problems in the petrochemical industry John Little

  18. Identify Dynamic Network Modules with Temporal and Spatial Constraints

    SciTech Connect (OSTI)

    Jin, R; McCallen, S; Liu, C; Almaas, E; Zhou, X J

    2007-09-24T23:59:59.000Z

    Despite the rapid accumulation of systems-level biological data, understanding the dynamic nature of cellular activity remains a difficult task. The reason is that most biological data are static, or only correspond to snapshots of cellular activity. In this study, we explicitly attempt to detangle the temporal complexity of biological networks by using compilations of time-series gene expression profiling data.We define a dynamic network module to be a set of proteins satisfying two conditions: (1) they form a connected component in the protein-protein interaction (PPI) network; and (2) their expression profiles form certain structures in the temporal domain. We develop the first efficient mining algorithm to discover dynamic modules in a temporal network, as well as frequently occurring dynamic modules across many temporal networks. Using yeast as a model system, we demonstrate that the majority of the identified dynamic modules are functionally homogeneous. Additionally, many of them provide insight into the sequential ordering of molecular events in cellular systems. We further demonstrate that identifying frequent dynamic network modules can significantly increase the signal to noise separation, despite the fact that most dynamic network modules are highly condition-specific. Finally, we note that the applicability of our algorithm is not limited to the study of PPI systems, instead it is generally applicable to the combination of any type of network and time-series data.

  19. MOBILE PHONE USE AND TEMPORAL SKIN HEAT SENSATION

    E-Print Network [OSTI]

    Boyer, Edmond

    in the phone by the battery currents and running of the radiofrequency (RF) electronic circuits measured the temperature of the temporal skin due to GSM 1800 MHz MP radiated power (125 mW). We suppressed of the heat produced in the phone by the battery currents and running of the radiofrequency (RF) electronic

  20. argentina tendencia temporal: Topics by E-print Network

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

    argentina tendencia temporal 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 La Politica de Derechos...

  1. Circuit Area Optimization in Energy Temporal Sparse Scenarios for

    E-Print Network [OSTI]

    Politècnica de Catalunya, Universitat

    Circuit Area Optimization in Energy Temporal Sparse Scenarios for Multiple Harvester Powered.alarcon@upc.edu Abstract--Multi-source energy harvesters are gaining interest as a robust alternative to power wireless sensors, since the sensor node can maintain its operation regardless of the fact that one of its energy

  2. Macro-temporal structure of storage ring free electron lasers

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    997 Macro-temporal structure of storage ring free electron lasers P. Elleaume Département de laser. Abstract. 2014 I derive simple dimensionless equations governing the storage ring free electron Ring Free Electron Laser (1) (S.R.L.), the S.R.L. was thought to be pseudo-continuous except for some

  3. Online Horizon Selection in Receding Horizon Temporal Logic Planning

    E-Print Network [OSTI]

    Murray, Richard M.

    - ative, short horizon solutions, using the currently observed state to compute a control strategy synthesis for temporal logic, but have thus far been limited by pursuing a single sequence of short horizon problems to the current goal. We propose a receding horizon algorithm for reactive synthesis that au

  4. Temporal Language Models for the Disclosure of Historical Text

    E-Print Network [OSTI]

    Hiemstra, Djoerd

    Introduction Historical and heritage collections consist for a considerable part of text and may incorporateTemporal Language Models for the Disclosure of Historical Text Franciska de Jong Henning Rode of the historical distance, access to this content is not straightforward. Historical variants of text are often

  5. Spatio-Temporal Conceptual Models: Data Structures + Space + Time

    E-Print Network [OSTI]

    Libre de Bruxelles, Université

    facilities. Responses to such requirements may be found in Geographic Information Systems (GIS), in some DBMS are needed. Major DBMS tools are incorporating facilities for spatial or temporal data management (e and of durability of the design specifications. It is thus foreseeable that a similar evolution will lead spatio

  6. The GLIMS Glacier Database: a spatio-temporal database

    E-Print Network [OSTI]

    Raup, Bruce H.

    The GLIMS Glacier Database: a spatio-temporal database implemented using Open Source tools Bruce countries #12;#12;#12;#12;#12;System components PostgreSQL (relational database) PostGIS (geospatial) GDAL (Geospatial Data Abstraction Library) Perl, PHP, Shapelib, ... #12;GLIMS Glacier Database System

  7. Dynamics Within an Organisation: Temporal Specification, Simulation and Evaluation

    E-Print Network [OSTI]

    Treur, Jan

    - 1 - Dynamics Within an Organisation: Temporal Specification, Simulation and Evaluation Catholijn is its dynamics. In this paper different types of specifications of properties of the dynamics within an organisation are introduced. Supporting tools for specification, simulation and analysis of dynamics within

  8. Optimal Control with Weighted Average Costs and Temporal Logic Specifications

    E-Print Network [OSTI]

    Murray, Richard M.

    Optimal Control with Weighted Average Costs and Temporal Logic Specifications Eric M. Wolff Control and Dynamical Systems California Institute of Technology Pasadena, California 91125 Email: ewolff@caltech.edu Ufuk Topcu Control and Dynamical Systems California Institute of Technology Pasadena, California 91125

  9. Ground surface temperatures in Canada: Spatial and temporal variability

    E-Print Network [OSTI]

    Long, Bernard

    show that the ground has warmed about 0.7 K in the last 100 years. Spatial variability is significant temperatures in Canada: Spatial and temporal variability, Geophys. Res. Lett., 30(10), 1499, doi:10.1029/2003GL inferred from geothermal data have shown that the study of perturbations to the Earth's energy balance

  10. Network Decontamination with Temporal Immunity by Cellular Automata

    E-Print Network [OSTI]

    Flocchini, Paola

    Network Decontamination with Temporal Immunity by Cellular Automata Yassine Daadaa, Paola Flocchini,flocchin,zaguia}@site.uottawa.ca Abstract. Network decontamination (or disinfection) is a widely stud- ied problem in distributed computing to decontaminate the whole network. In the vast literature a variety of as- sumptions are made on the power

  11. Temporal-Harmonic Specific POD Mode Extraction Gilead Tadmor

    E-Print Network [OSTI]

    Dabiri, John O.

    Temporal-Harmonic Specific POD Mode Extraction Gilead Tadmor and Daniel Bissex Electrical changes the systems mean field changes significantly, as does the leading shedding harmonic4 , once mode pair will capture harmonically rich time dynamics, reflecting a spatial mix of multiple vortical

  12. Range Temporal Search on Sensor-rich Mobile Videos Preliminaries

    E-Print Network [OSTI]

    Shahabi, Cyrus

    Range Temporal Search on Sensor-rich Mobile Videos Preliminaries FOV model - A video as a set of video frames - Each video frame is modeled a Field Of View (FOV) based on the metadata (location, orientation, timestamp, etc.) of the video. - Note the size of is the maximum visible distance

  13. Temporal Segmentation of Egocentric Videos Yair Poleg Chetan Arora

    E-Print Network [OSTI]

    Peleg, Shmuel

    Temporal Segmentation of Egocentric Videos Yair Poleg Chetan Arora Shmuel Peleg The Hebrew life logging egocentric videos. Browsing such long unstruc- tured videos is time consuming and tedious videos, enabling ef- ficient browsing, indexing and summarization of the long videos. Two sources

  14. Incorporating Temporal Reasoning into Activity Recognition for Smart Home Residents

    E-Print Network [OSTI]

    Cook, Diane J.

    Incorporating Temporal Reasoning into Activity Recognition for Smart Home Residents Geetika Singla be employed for valuable functions such as at- home health monitoring. In this project, we are using smart-2752 {gsingla, djcook, schmitter-e}@wsu.edu Abstract Smart environments rely on artificial intelligence

  15. Theory of Neutron Noise in a Temporally Fluctuating Multiplying Medium

    E-Print Network [OSTI]

    Pázsit, Imre

    Theory of Neutron Noise in a Temporally Fluctuating Multiplying Medium Lénárd Pál KFKI Atomic, respec- tively. In this paper we develop a theory of neutron fluctuations in a medium randomly varying place in a time-varying environment. I. INTRODUCTION The theory of neutron fluctuations in multiplying

  16. Short-term Variations in the Galactic Environment of the Sun

    E-Print Network [OSTI]

    Priscilla C. Frisch; Jonathan D. Slavin

    2006-01-17T23:59:59.000Z

    The galactic environment of the Sun varies over short timescales as the Sun and interstellar clouds travel through space. Small variations in the dynamics, ionization, density, and magnetic field strength of the interstellar medium (ISM) surrounding the Sun yield pronounced changes in the heliosphere. We discuss essential information required to understand short-term variations in the galactic environment of the Sun, including the distribution and radiative transfer properties of nearby ISM, and variations in the boundary conditions of the heliosphere as the Sun traverses clouds. The most predictable transitions are when the Sun emerged from the Local Bubble interior and entered the cluster of local interstellar clouds flowing past the Sun, within the past 140,000 years, and again when the Sun entered the local interstellar cloud now surrounding and inside of the solar system, sometime during the past 44,000 years.

  17. Universal Quantification for Self-Organized Criticality in Atmospheric Flows

    E-Print Network [OSTI]

    A. Mary Selvam

    1997-10-09T23:59:59.000Z

    Atmospheric flows exhibit selfsimilar fluctuations on all scales(space-time) ranging from climate(kilometers/years) to turbulence(millimeters/seconds) manifested as fractal geometry to the global cloud cover pattern concomitant with inverse power law form for power spectra of temporal fluctuations. Selfsimilar fluctuations implying long-range correlations are ubiquitous to dynamical systems in nature and are identified as signatures of self-organized criticality in atmospheric flows. Also, mathematical models for simulation and prediction of atmospheric flows are nonlinear and computer realizations give unrealistic solutions because of deterministic chaos, a direct consequence of finite precision round-off error doubling for each iteration of iterative computations incorporated in long-term numerical integration schemes used for model solutions An alternative non-deterministic cell dynamical system model predicts, (a): the observed self organized criticality as a consequence of quantumlike mechanics governing flow dynamics,.(b):atmospheric flows trace an overall logarithmic spiral trajectory with the quasiperiodic Penrose tiling pattern for the internal structure,(c): eddy circulation structure follows Kepler's third law of planetary motion and results in inverse square law form for centripetal acceleration. The inertial masses representing the eddy circulation therefore follow laws analogous to the Newton's inverse square law for gravitation. The model is similar to a superstring model for subatomic dynamics which unifies quantum mechanical and classical concept and incorporates gravitational forces along with nuclear and electromagnetic forces.

  18. Systematic characterization of degas-driven flow for poly(dimethylsiloxane) microfluidic devices

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

    Lee, Luke P.; Liang, David Y.; Tentori, Augusto M.; Dimov, Ivan K.

    2011-06-02T23:59:59.000Z

    Degas-driven flow is a novel phenomenon used to propel fluids in poly(dimethylsiloxane) (PDMS)-based microfluidic devices without requiring any external power. This method takes advantage of the inherently high porosity and air solubility of PDMS by removing air molecules from the bulk PDMS before initiating the flow. The dynamics of degas-driven flow are dependent on the channel and device geometries and are highly sensitive to temporal parameters. These dependencies have not been fully characterized, hindering broad use of degas-driven flow as a microfluidic pumping mechanism. Here, we characterize, for the first time, the effect of various parameters on the dynamics ofmore »degas-driven flow, including channel geometry, PDMS thickness, PDMS exposure area, vacuum degassing time, and idle time at atmospheric pressure before loading. We investigate the effect of these parameters on flow velocity as well as channel fill time for the degas-driven flow process. Using our devices, we achieved reproducible flow with a standard deviation of less than 8% for flow velocity, as well as maximum flow rates of up to 3 nL/s and mean flow rates of approximately 1-1.5 nL/s. Parameters such as channel surface area and PDMS chip exposure area were found to have negligible impact on degas-driven flow dynamics, whereas channel cross-sectional area, degas time, PDMS thickness, and idle time were found to have a larger impact. In addition, we develop a physical model that can predict mean flow velocities within 6% of experimental values and can be used as a tool for future design of PDMS-based microfluidic devices that utilize degas-driven flow.« less

  19. Systematic characterization of degas-driven flow for poly(dimethylsiloxane) microfluidic devices

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

    Lee, Luke P.; Liang, David Y.; Tentori, Augusto M.; Dimov, Ivan K. [Universidad de Valparaiso (Chile)

    2011-06-02T23:59:59.000Z

    Degas-driven flow is a novel phenomenon used to propel fluids in poly(dimethylsiloxane) (PDMS)-based microfluidic devices without requiring any external power. This method takes advantage of the inherently high porosity and air solubility of PDMS by removing air molecules from the bulk PDMS before initiating the flow. The dynamics of degas-driven flow are dependent on the channel and device geometries and are highly sensitive to temporal parameters. These dependencies have not been fully characterized, hindering broad use of degas-driven flow as a microfluidic pumping mechanism. Here, we characterize, for the first time, the effect of various parameters on the dynamics of degas-driven flow, including channel geometry, PDMS thickness, PDMS exposure area, vacuum degassing time, and idle time at atmospheric pressure before loading. We investigate the effect of these parameters on flow velocity as well as channel fill time for the degas-driven flow process. Using our devices, we achieved reproducible flow with a standard deviation of less than 8% for flow velocity, as well as maximum flow rates of up to 3 nL/s and mean flow rates of approximately 1-1.5 nL/s. Parameters such as channel surface area and PDMS chip exposure area were found to have negligible impact on degas-driven flow dynamics, whereas channel cross-sectional area, degas time, PDMS thickness, and idle time were found to have a larger impact. In addition, we develop a physical model that can predict mean flow velocities within 6% of experimental values and can be used as a tool for future design of PDMS-based microfluidic devices that utilize degas-driven flow.

  20. Parallel flow diffusion battery

    DOE Patents [OSTI]

    Yeh, H.C.; Cheng, Y.S.

    1984-01-01T23:59:59.000Z

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  1. Optical flow switching

    E-Print Network [OSTI]

    Chan, Vincent W. S.

    Present-day networks are being challenged by dramatic increases in bandwidth demand of emerging applications. We will explore a new transport, ldquooptical flow switchingrdquo, that will enable significant growth and ...

  2. Olefin Autoxidation in Flow

    E-Print Network [OSTI]

    Neuenschwander, Ulrich

    Handling hazardous multiphase reactions in flow brings not only safety advantages but also significantly improved performance, due to better mass transfer characteristics. In this paper, we present a continuous microreactor ...

  3. Assessment of Controlling Processes for Field-Scale Uranium Reactive Transport under Highly Transient Flow Conditions

    SciTech Connect (OSTI)

    Ma, Rui; Zheng, Chunmiao; Liu, Chongxuan; Greskowiak, Janek; Prommer, Henning; Zachara, John M.

    2014-02-13T23:59:59.000Z

    This paper presents the results of a comprehensive model-based analysis of a uranium tracer test conducted at the U.S Department of Energy Hanford 300 Area (300A) IFRC site. A three-dimensional multi-component reactive transport model was employed to assess the key factors and processes that control the field-scale uranium reactive transport. Taking into consideration of relevant physical and chemical processes, the selected conceptual/numerical model replicates the spatial and temporal variations of the observed U(VI) concentrations reasonably well in spite of the highly complex field conditions. A sensitivity analysis was performed to interrogate the relative importance of various processes and factors for reactive transport of U(VI) at the field-scale. The results indicate that multi-rate U(VI) sorption/desorption, U(VI) surface complexation reactions, and initial U(VI) concentrations were the most important processes and factors controlling U(VI) migration. On the other hand, cation exchange reactions, the choice of the surface complexation model, and dual-domain mass transfer processes, which were previously identified to be important in laboratory experiments, played less important roles under the field-scale experimental condition at the 300A site. However, the model simulations also revealed that the groundwater chemistry was relatively stable during the uranium tracer experiment and therefore presumably not dynamic enough to appropriately assess the effects of ion exchange reaction and the choice of surface complexation models on U(VI) sorption and desorption. Furthermore, it also showed that the field experimental duration (16 days) was not sufficiently long to precisely assess the role of a majority of the sorption sites that were accessed by slow kinetic processes within the dual domain model. The sensitivity analysis revealed the crucial role of the intraborehole flow that occurred within the long-screened monitoring wells and thus significantly affected both field-scale measurements and simulated U(VI) concentrations as a combined effect of aquifer heterogeneity and highly dynamic flow conditions. Overall, this study, which provides one of the few detailed and highly data-constrained uranium transport simulations, highlights the difference in controlling processes between laboratory and field scale that prevent a simple direct upscaling of laboratory-scale models.

  4. Air-flow regulation system for a coal gasifier

    DOE Patents [OSTI]

    Fasching, George E. (Morgantown, WV)

    1984-01-01T23:59:59.000Z

    An improved air-flow regulator for a fixed-bed coal gasifier is provided which allows close air-flow regulation from a compressor source even though the pressure variations are too rapid for a single primary control loop to respond. The improved system includes a primary controller to control a valve in the main (large) air supply line to regulate large slow changes in flow. A secondary controller is used to control a smaller, faster acting valve in a secondary (small) air supply line parallel to the main line valve to regulate rapid cyclic deviations in air flow. A low-pass filter with a time constant of from 20 to 50 seconds couples the output of the secondary controller to the input of the primary controller so that the primary controller only responds to slow changes in the air-flow rate, the faster, cyclic deviations in flow rate sensed and corrected by the secondary controller loop do not reach the primary controller due to the high frequency rejection provided by the filter. This control arrangement provides at least a factor of 5 improvement in air-flow regulation for a coal gasifier in which air is supplied by a reciprocating compressor through a surge tank.

  5. Conjugate flow action functionals

    SciTech Connect (OSTI)

    Venturi, Daniele, E-mail: daniele-venturi@brown.edu [Division of Applied Mathematics, Brown University, Rhode Island 02912 (United States)] [Division of Applied Mathematics, Brown University, Rhode Island 02912 (United States)

    2013-11-15T23:59:59.000Z

    We present a new general framework to construct an action functional for a non-potential field theory. The key idea relies on representing the governing equations relative to a diffeomorphic flow of curvilinear coordinates which is assumed to be functionally dependent on the solution field. Such flow, which will be called the conjugate flow, evolves in space and time similarly to a physical fluid flow of classical mechanics and it can be selected in order to symmetrize the Gâteaux derivative of the field equations with respect to suitable local bilinear forms. This is equivalent to requiring that the governing equations of the field theory can be derived from a principle of stationary action on a Lie group manifold. By using a general operator framework, we obtain the determining equations of such manifold and the corresponding conjugate flow action functional. In particular, we study scalar and vector field theories governed by second-order nonlinear partial differential equations. The identification of transformation groups leaving the conjugate flow action functional invariant could lead to the discovery of new conservation laws in fluid dynamics and other disciplines.

  6. Section 13: Flow control 1 Section 13: Flow control

    E-Print Network [OSTI]

    Kohlenbach, Ulrich

    Geometries for Energyefficient Flow Around Bodies Abstract 14:30 ­ 14:50: Elfriede Friedmann (Universität

  7. Accounting for population variation in targeted proteomics

    SciTech Connect (OSTI)

    Fujimoto, Grant M.; Monroe, Matthew E.; Rodriguez, Larissa M.; Wu, Chaochao; MacLean, Brendan; Smith, Richard D.; MacCoss, Michael; Payne, Samuel H.

    2014-01-03T23:59:59.000Z

    Individual proteomes typically differ from the reference human proteome at ~10,000 single amino acid variants. When viewed at the population scale, this individual variation results in a wide variety of protein sequences. In targeted proteomics experiments, such variability would confound accurate protein quantification. To facilitate researchers in identifying target peptides with high variability within the human population we have created the Population Variation plug-in for Skyline, which provides easy access to the polymorphisms stored in dbSNP. Given a set of peptides, the tool reports minor allele frequency for common polymorphisms. We highlight the importance of considering genetic variation by applying the tool to public datasets.

  8. Undecidability and temporal logic: some landmarks from Turing to the present

    E-Print Network [OSTI]

    Goranko, Valentin

    . INTRODUCTION Temporal logic was born in the mid 1950s, right after the death of Alan Turing in temporal logic was essentially Alan Turing's celebrated Undecidability of the Halting problem of (what

  9. Spatio-temporal changes in CO2 emissions during the second ZERT...

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

    Spatio-temporal changes in CO2 emissions during the second ZERT injection, August-September 2008. Spatio-temporal changes in CO2 emissions during the second ZERT injection,...

  10. Timing in the Absence of Supraspinal Input: Effects of Temporally Regular Stimulation on Spinal Plasticity

    E-Print Network [OSTI]

    Lee, Kuan Hsien

    2013-08-08T23:59:59.000Z

    task, in which response-contingent leg shock produces an increase in flexion duration. Exposure to temporally regular stimulation (fixed spaced stimulation; FT) promotes learning, and temporally irregular stimulation produces a learning deficit...

  11. A Corticostriatal Neural System Enhances Auditory Perception through Temporal Context Processing

    E-Print Network [OSTI]

    Geiser, Eveline

    The temporal context of an acoustic signal can greatly influence its perception. The present study investigated the neural correlates underlying perceptual facilitation by regular temporal contexts in humans. Participants ...

  12. arbitrary spatio-temporal tactile: Topics by E-print Network

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

    manage spatio-temporal data. These applications typically run on top of a relational DBMS and manage spatio-temporal data either using the DBMS, which provides little support,...

  13. Rotordynamic characteritics of incompressible-flow labyrinth seals

    E-Print Network [OSTI]

    Ghali, Anupama

    1993-01-01T23:59:59.000Z

    ) . Parsons (1938) was apparently the first to introduce the labyrinth seal in his development of a steam turbine near the turn of the century The objective of the seal is to create a highly frictional flow path between high-pressure and low... to point out the unstable vibrations due to labyrinth seals. He discovered that the circumferential variation of pressure in the labyrinth seal caused excitation forces, which in turn were responsible for the rotor whirl in axial compressors...

  14. Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I.Skillicorn 1 Azimuthal asymmetry

    E-Print Network [OSTI]

    Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I.Skillicorn 1 Azimuthal asymmetry using energy flow method Azimuthal angle distribution at Q2 >100 GeV2 Energy flow method.Ukleja on behalf of the ZEUS Collaboration #12; Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I

  15. Modeling Temporal Primitives: Back to Basics Iqbal A. Goralwalla, Yuri Leontiev, M. Tamer Ozsu and Duane Szafron

    E-Print Network [OSTI]

    Szafron, Duane

    Modeling Temporal Primitives: Back to Basics Iqbal A. Goralwalla, Yuri Leontiev, M. Tamer ¨Ozsu of the design space of any temporal model since it is comprised of the basic temporal features that un- derlie

  16. Individual variation in cooperative behaviour in meerkats

    E-Print Network [OSTI]

    English, Sinéad

    2010-04-13T23:59:59.000Z

    Individual variation in cooperation is a striking yet poorly understood feature of many animal societies, particularly in cooperative breeders where individuals assist in the care of young that are not their own. While previous research...

  17. Characterization of the reactive flow field dynamics in a gas turbine injector using high frequency PIV

    E-Print Network [OSTI]

    Barbosa, Séverine; Ducruix, Sébastien

    2008-01-01T23:59:59.000Z

    The present work details the analysis of the aerodynamics of an experimental swirl stabilized burner representative of gas turbine combustors. This analysis is carried out using High Frequency PIV (HFPIV) measurements in a reactive situation. While this information is usually available at a rather low rate, temporally resolved PIV measurements are necessary to better understand highly turbulent swirled flows, which are unsteady by nature. Thanks to recent technical improvements, a PIV system working at 12 kHz has been developed to study this experimental combustor flow field. Statistical quantities of the burner are first obtained and analyzed, and the measurement quality is checked, then a temporal analysis of the velocity field is carried out, indicating that large coherent structures periodically appear in the combustion chamber. The frequency of these structures is very close to the quarter wave mode of the chamber, giving a possible explanation for combustion instability coupling.

  18. Vehicle tracking with multi-temporal hyperspectral imagery John Kerekes*

    E-Print Network [OSTI]

    Kerekes, John

    of vegetation, minerals, and even man-made construction materials can be distinguished through measurement from variation in the production process, uneven weathering as well as contamination from natural

  19. Author's personal copy Temporal and spatial trends of total petroleum hydrocarbons in the seawater

    E-Print Network [OSTI]

    Ma, Lena

    Author's personal copy Temporal and spatial trends of total petroleum hydrocarbons in the seawater hydrocarbons Bohai Bay Temporal and spatial trends Seawater a b s t r a c t The temporal and spatial distribution of total petroleum hydrocarbons (TPH) in the seawater of Tianjin Bohai Bay during 1996

  20. On the Formal Analysis of a Spatio-Temporal Role-Based Access Control Model

    E-Print Network [OSTI]

    Ray, Indrakshi

    On the Formal Analysis of a Spatio-Temporal Role-Based Access Control Model Manachai Toahchoodee. For crit- ical applications, a model for spatio-temporal-based access control is needed that increases. Consequently, researchers have proposed various spatio-temporal access control models that are useful

  1. Spatio-temporal Access Methods Mohamed F. Mokbel Thanaa M. Ghanem Walid G. Aref

    E-Print Network [OSTI]

    Mokbel, Mohamed F.

    and predicted future positions. In this short survey, we classify spatio-temporal access methods for each Introduction Spatio-temporal databases deal with objects that change their location and/or shape over time. A typical example of spatio-temporal databases is moving objects in the £ -dimensional space. Moving objects

  2. Stochastic dynamics of active swimmers in linear flows

    E-Print Network [OSTI]

    Mario Sandoval; Navaneeth K. M.; Ganesh Subramanian; Eric Lauga

    2014-06-17T23:59:59.000Z

    Most classical work on the hydrodynamics of low-Reynolds-number swimming addresses deterministic locomotion in quiescent environments. Thermal fluctuations in fluids are known to lead to a Brownian loss of the swimming direction. As most cells or synthetic swimmers are immersed in external flows, we consider theoretically in this paper the stochastic dynamics of a model active particle (a self-propelled sphere) in a steady general linear flow. The stochasticity arises both from translational diffusion in physical space, and from a combination of rotary diffusion and run-and-tumble dynamics in orientation space. We begin by deriving a general formulation for all components of the long-time mean square displacement tensor for a swimmer with a time-dependent swimming velocity and whose orientation decorrelates due to rotary diffusion alone. This general framework is applied to obtain the convectively enhanced mean-squared displacements of a steadily-swimming particle in three canonical linear flows (extension, simple shear, and solid-body rotation). We then show how to extend our results to the case where the swimmer orientation also decorrelates on account of run-and-tumble dynamics. Self-propulsion in general leads to the same long-time temporal scalings as for passive particles in linear flows but with increased coefficients. In the particular case of solid-body rotation, the effective long-time diffusion is the same as that in a quiescent fluid, and we clarify the lack of flow-dependence by briefly examining the dynamics in elliptic linear flows. By comparing the new active terms with those obtained for passive particles we see that swimming can lead to an enhancement of the mean-square displacements by orders of magnitude, and could be relevant for biological organisms or synthetic swimming devices in fluctuating environmental or biological flows.

  3. Optical Monitoring of BL Lac Object S5 0716+714 with High Temporal Resolution

    E-Print Network [OSTI]

    Jianghua Wu; Bo Peng; Xu Zhou; Jun Ma; Zhaoji Jiang; Jiansheng Chen

    2005-01-11T23:59:59.000Z

    Optical monitoring of S5 0716+714 was performed with a 60/90 Schmidt telescope in 2003 November and December and 2004 January for studying the variability of the object on short timescales. Due to the high brightness of the source we could carry out quasi-simultaneous measurements in three bands with a temporal resolution of about 20 minutes by using one single telescope. Intraday and intranight variations were observed with an overall change of ~0.9 mag during the whole campaign. Two outbursts were recorded on JD 2453005 and JD 2453009. Minimum timescales of a few hours were derived from the light curves of individual nights but were different from night to night. A bluer-when-brighter chromatism was present when the object was in fast flare, but was absent when it was in a relatively quiescent state. Our results are basically consistent with the shock-in-jet model and demonstrate that the geometrical effects can sometimes play an important role in the variability of blazars.

  4. Modeling Temporal-Spatial Earthquake and Volcano Clustering at Yucca Mountain, Nevada

    SciTech Connect (OSTI)

    T. Parsons; G.A. Thompson; A.H. Cogbill

    2006-05-31T23:59:59.000Z

    The proposed national high-level nuclear repository at Yucca Mountain is close to Quaternary faults and cinder cones. The frequency of these events is low, with indications of spatial and temporal clustering, making probabilistic assessments difficult. In an effort to identify the most likely intrusion sites, we based a 3D finite element model on the expectation that faulting and basalt intrusions are primarily sensitive to the magnitude and orientation of the least principal stress in extensional terranes. We found that in the absence of fault slip, variation in overburden pressure caused a stress state that preferentially favored intrusions at Crater Flat. However, when we allowed central Yucca Mountain faults to slip in the model, we found that magmatic clustering was not favored at Crater Flat or in the central Yucca Mountain block. Instead, we calculated that the stress field was most encouraging to intrusions near fault terminations, consistent with the location of the most recent volcanism at Yucca Mountain, the Lathrop Wells cone. We found this linked fault and magmatic system to be mutually reinforcing in the model in that dike inflation favored renewed fault slip.

  5. Piezoelectric axial flow microvalve

    SciTech Connect (OSTI)

    Gemmen, Randall; Thornton, Jimmy; Vipperman, Jeffrey S.; Clark, William W.

    2007-01-09T23:59:59.000Z

    This invention is directed to a fuel cell operable with a quantity of fuel and a quantity of an oxidizer to produce electrical power, the fuel cell including a fuel cell body including a labyrinth system structured to permit the fuel and the oxidizer to flow therethrough; at least a first catalyst in fluid communication with the labyrinth; and at least a first microvalve operably disposed within at least a portion of the labyrinth. The microvalve utilizes a deflectable member operable upon the application of a voltage from a voltage source. The microvalve includes an elongated flow channel formed therein and extending substantially longitudinally between the first and second ends to permit substantially longitudinal flow of the fluid therethrough and between the first and second ends; and the deflectable member disposed on the valve body, the deflectable member including at least a first piezoelectric portion that is piezoelectrically operable to deflect the deflectable member between an open position and a closed position upon the application of a voltage, the deflectable member in the closed position being operable to resist the flow of the fluid through the flow channel.

  6. Spatial-temporal event detection in climate parameter imagery.

    SciTech Connect (OSTI)

    McKenna, Sean Andrew; Gutierrez, Karen A.

    2011-10-01T23:59:59.000Z

    Previously developed techniques that comprise statistical parametric mapping, with applications focused on human brain imaging, are examined and tested here for new applications in anomaly detection within remotely-sensed imagery. Two approaches to analysis are developed: online, regression-based anomaly detection and conditional differences. These approaches are applied to two example spatial-temporal data sets: data simulated with a Gaussian field deformation approach and weekly NDVI images derived from global satellite coverage. Results indicate that anomalies can be identified in spatial temporal data with the regression-based approach. Additionally, la Nina and el Nino climatic conditions are used as different stimuli applied to the earth and this comparison shows that el Nino conditions lead to significant decreases in NDVI in both the Amazon Basin and in Southern India.

  7. Temporal process of plasma discharge by an electron beam

    SciTech Connect (OSTI)

    Sugawa, M.; Sugaya, R.; Isobe, S.; Kumar, A. [Department of Physics, Faculty of Science, Ehime University, Matsuyama 790 (Japan); Honda, H. [Institute of Laser Engineering, Osaka University, Suita, Osaka 565 (Japan)

    1996-05-01T23:59:59.000Z

    The process of the plasma discharge due to an electron beam is experimentally investigated. A pulse ({approximately}540 {mu}s) of an electron beam (0.5{endash}1.5 keV, {le}20 mA) is injected into argon gas (5{times}10{sup {minus}5}{endash}5{times}10{sup {minus}4} Torr) in a magnetic field (50{endash}300 G). The discharge based on a gas break down occurs cascade-likely in time. The gas beak down with some steps is explained by the two stream instability of an electron beam-plasma system, from the observation of the temporal evolution of the frequency spectra (0{endash}3.0 GHz) of the instability and the measurement of the temporal plasma density and temperature. {copyright} {ital 1996 American Institute of Physics.}

  8. Dynamics of Turing patterns under spatio-temporal forcing

    E-Print Network [OSTI]

    S. Rudiger; D. G. Miguez; A. P. Munuzuri; F. Sagues; J. Casademunt

    2003-01-31T23:59:59.000Z

    We study, both theoretically and experimentally, the dynamical response of Turing patterns to a spatio-temporal forcing in the form of a travelling wave modulation of a control parameter. We show that from strictly spatial resonance, it is possible to induce new, generic dynamical behaviors, including temporally-modulated travelling waves and localized travelling soliton-like solutions. The latter make contact with the soliton solutions of P. Coullet Phys. Rev. Lett. {\\bf 56}, 724 (1986) and provide a general framework which includes them. The stability diagram for the different propagating modes in the Lengyel-Epstein model is determined numerically. Direct observations of the predicted solutions in experiments carried out with light modulations in the photosensitive CDIMA reaction are also reported.

  9. Temporal Intermittency of Energy Dissipation in Magnetohydrodynamic Turbulence

    E-Print Network [OSTI]

    Zhdankin, Vladimir; Boldyrev, Stanislav

    2015-01-01T23:59:59.000Z

    Energy dissipation in magnetohydrodynamic (MHD) turbulence is known to be highly intermittent in space, being concentrated in sheet-like coherent structures. Much less is known about intermittency in time, another fundamental aspect of turbulence which has great importance for observations of solar flares and other space/astrophysical phenomena. In this Letter, we investigate the temporal intermittency of energy dissipation in numerical simulations of MHD turbulence. We consider four-dimensional spatiotemporal structures, "flare events", responsible for a large fraction of the energy dissipation. We find that although the flare events are often highly complex, they exhibit robust power-law distributions and scaling relations. We find that the probability distribution of dissipated energy has a power law index close to -1.75, similar to observations of solar flares, indicating that intense dissipative events dominate the heating of the system. We also discuss the temporal asymmetry of flare events as a signatu...

  10. Flow Intermittency, Dispersion, and Correlated Continuous Time Random Walks in Porous Media

    SciTech Connect (OSTI)

    de Anna, Pietro; Le Borgne, Tanguy; Dentz, Marco; Tartakovsky, Alexandre M.; Bolster, Diogo; Davy, Philippe

    2013-05-01T23:59:59.000Z

    We study the intermittency of fluid velocities in porous media and its relation to anomalous dispersion. Lagrangian velocities measured at equidistant points along streamlines are shown to form a spatial Markov process. As a consequence of this remarkable property, the dispersion of fluid particles can be described by a continuous time random walk with correlated temporal increments. This new dynamical picture of intermittency provides a direct link between the microscale flow, its intermittent properties, and non-Fickian dispersion.

  11. Satellite observations and estimates of surface flow in the northwestern Gulf of Mexico

    E-Print Network [OSTI]

    Barron, Charlie Nelms

    1992-01-01T23:59:59.000Z

    methods of observation do not provide sufficient spatial and temporal coverage and resolution to reliably depict surface flow on the required scales. In earlier studies, researchers extracted information on the nature of Gulf circulation from historical... 1992) Charlie Nelms Barron Jr. , B. S. , Texas A&M University Co-Chairs of Advisory Committee: Dr. Andrew C. Vastano Dr. Robert O. Reid Data from two satellite-based instrument systems are used to provide a description of the surface circulation...

  12. Temporal trends of contaminants recorded in sediments of Puget Sound

    SciTech Connect (OSTI)

    Crecelius, E.A.; Curl, H.C. Jr.

    1988-03-01T23:59:59.000Z

    This paper discusses the temporal trends of contamination that can be inferred from the chemical composition of age-dated sediment cores from central Puget Sound. The fine-grain sediment (less than 10% sand) of the deep region (>150m) of central Puget Sound, which accumulates relatively undisturbed sediment at a rate of approximately 1 cm per year, provides a useful record of the history of contamination. 21 refs., 4 figs.

  13. Variation and power issues in VLSI clock networks

    E-Print Network [OSTI]

    Venkataraman, Ganesh

    2009-05-15T23:59:59.000Z

    to variations. In skew scheduling, an estimation of variations based on clock sink locations is employed to guide skew safety margin towards sink pairs which are more vulnerable to variations. Abstract topology is generated based on the estimated delay targets...

  14. The effect of laser pulse shape variations on the adiabat of NIF capsule implosions

    SciTech Connect (OSTI)

    Robey, H. F.; MacGowan, B. J.; Landen, O. L.; LaFortune, K. N.; Widmayer, C.; Celliers, P. M.; Moody, J. D.; Ross, J. S.; Ralph, J.; LePape, S.; Berzak Hopkins, L. F.; Spears, B. K.; Haan, S. W.; Clark, D.; Lindl, J. D.; Edwards, M. J. [LLNL, Livermore, California 94550 (United States)] [LLNL, Livermore, California 94550 (United States)

    2013-05-15T23:59:59.000Z

    Indirectly driven capsule implosions on the National Ignition Facility (NIF) [Moses et al., Phys. Plasmas 16, 041006 (2009)] are being performed with the goal of compressing a layer of cryogenic deuterium-tritium (DT) fuel to a sufficiently high areal density (?R) to sustain the self-propagating burn wave that is required for fusion power gain greater than unity. These implosions are driven with a temporally shaped laser pulse that is carefully tailored to keep the DT fuel on a low adiabat (ratio of fuel pressure to the Fermi degenerate pressure). In this report, the impact of variations in the laser pulse shape (both intentionally and unintentionally imposed) on the in-flight implosion adiabat is examined by comparing the measured shot-to-shot variations in ?R from a large ensemble of DT-layered ignition target implosions on NIF spanning a two-year period. A strong sensitivity to variations in the early-time, low-power foot of the laser pulse is observed. It is shown that very small deviations (?0.1% of the total pulse energy) in the first 2 ns of the laser pulse can decrease the measured ?R by 50%.

  15. 1988 Wet deposition temporal and spatial patterns in North America

    SciTech Connect (OSTI)

    Simpson, J.C.; Olsen, A.R.; Bittner, E.A.

    1992-03-01T23:59:59.000Z

    The focus of this report is on North American wet deposition temporal patterns from 1979 to 1988 and spatial patterns for 1988. It is the third in a series of reports that investigate the patterns of annual precipitation-weighted average concentration and annual deposition for nine ion species: hydrogen, sulfate, nitrate, ammonium, calcium, chloride, sodium, potassium, and magnesium. Mosaic maps, based on surface estimation using kriging, display concentration and deposition spatial patterns of pH, hydrogen, sulfate, nitrate, ammonium, and calcium ion species for 1988 annual, winter, and summer periods. Temporal pattern analyses use a subset of 35 sites over a 10-year (1979--1988) period and an expanded subset of 137 sites, with greater spatial coverage, over a 7-year (1982--1988) period. The 10-year period represents the longest period with wet deposition monitoring data available that has a sufficient number of sites with data of known quality to allow a descriptive summary of annual temporal patterns. Sen's median trend estimate and Kendall's seasonal tau (KST) test are calculated for each ion species concentration and deposition at each site in both subsets.

  16. 1988 Wet deposition temporal and spatial patterns in North America

    SciTech Connect (OSTI)

    Simpson, J.C.; Olsen, A.R.; Bittner, E.A.

    1992-03-01T23:59:59.000Z

    The focus of this report is on North American wet deposition temporal patterns from 1979 to 1988 and spatial patterns for 1988. It is the third in a series of reports that investigate the patterns of annual precipitation-weighted average concentration and annual deposition for nine ion species: hydrogen, sulfate, nitrate, ammonium, calcium, chloride, sodium, potassium, and magnesium. Mosaic maps, based on surface estimation using kriging, display concentration and deposition spatial patterns of pH, hydrogen, sulfate, nitrate, ammonium, and calcium ion species for 1988 annual, winter, and summer periods. Temporal pattern analyses use a subset of 35 sites over a 10-year (1979--1988) period and an expanded subset of 137 sites, with greater spatial coverage, over a 7-year (1982--1988) period. The 10-year period represents the longest period with wet deposition monitoring data available that has a sufficient number of sites with data of known quality to allow a descriptive summary of annual temporal patterns. Sen`s median trend estimate and Kendall`s seasonal tau (KST) test are calculated for each ion species concentration and deposition at each site in both subsets.

  17. Temporal modulation of plasma species in atmospheric dielectric barrier discharges

    SciTech Connect (OSTI)

    Yang, Aijun; Wang, Xiaohua, E-mail: xhw@mail.xjtu.edu.cn, E-mail: mzrong@mail.xjtu.edu.cn; Liu, Dingxin; Rong, Mingzhe, E-mail: xhw@mail.xjtu.edu.cn, E-mail: mzrong@mail.xjtu.edu.cn [Centre for Plasma Biomedicine, State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049 (China); Kong, Michael G. [Centre for Plasma Biomedicine, State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049 (China); Frank Reidy Research Center for Bioelectrics, Department of Electrical and Computer Engineering, Old Dominion University, Virginia 23508 (United States); Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia 23529 (United States)

    2014-07-15T23:59:59.000Z

    The atmospheric pressure dielectric barrier discharge in helium is a pulsed discharge in nature and the moment of maximum species densities is almost consistent with peak discharge current density. In this paper, a one-dimensional fluid model is used to investigate the temporal structure of plasma species in an atmospheric He-N{sub 2} dielectric barrier discharge (DBD). It is demonstrated that there exist microsecond delays of the moments of the maximum electron and ion densities from the peak of discharge current density. These time delays are caused by a competition between the electron impact and Penning ionizations, modulated by the N{sub 2} level in the plasma-forming gas. Besides, significant electron wall losses lead to the DBD being more positively charged and, with a distinct temporal separation in the peak electron and cation densities, the plasma is characterized with repetitive bursts of net positive charges. The temporal details of ionic and reactive plasma species may provide a new idea for some biological processes.

  18. TRiPoD (Temporal Relationalism incorporating Principles of Dynamics)

    E-Print Network [OSTI]

    Edward Anderson

    2015-01-30T23:59:59.000Z

    Temporal Relationalism is that there is no time for the universe as a whole at the primary level. Time emerges rather at a secondary level; one compelling idea for this is Mach's: that time is to be abstracted from change. Temporal Relationalism leads to, and better explains, the well-known Frozen Formalism Problem encountered in GR and other background-independent theories at the quantum level. Abstraction from change is then a type of emergent time resolution of this. Moreover, the Frozen Formalism Problem is but one of the many Problem of Time facets, which are notoriously interconnected. The current article concerns modifications of physical formalism which ensure that once Temporal Relationalism is resolved, it stays incorporated. At the classical level, this involves modifying much of the Principles of Dynamics. I first introduce the anti-Routhian to complete the Legendre square of Lagrangian, Hamiltonian and Routhian. I next pass from velocities $\\dot{Q}\\mbox{}^{A}$ to changes d$Q^{A}$. Then Lagrangians are supplanted by Jacobi arc elements, Euler--Lagrange equations by Jacobi--Mach ones, and momentum requires redefining but actions remain unchanged. A differential (d) version of the Hamiltonian is required, giving rise to a variant of the Dirac approach based on a d-almost Hamiltonian subcase of the d-anti Routhian. On the other hand, the forms of the constraints themselves, and of Hamilton--Jacobi theory, remain unaltered.

  19. Gaseous Flows in Galaxies

    E-Print Network [OSTI]

    F. Combes

    2007-09-02T23:59:59.000Z

    The gas component plays a major role in the dynamics of spiral galaxies, because of its dissipative character, and its ability to exchange angular momentum with stars in the disk. Due to its small velocity dispersion, it triggers gravitational instabilities, and the corresponding non-axisymmetric patterns produce gravity torques, which mediate these angular momentum exchanges. When a srong bar pattern develops with the same pattern speed all over the disk, only gas inside corotation can flow towards the center. But strong bars are not long lived in presence of gas, and multiple-speed spiral patterns can develop between bar phases, and help the galaxy to accrete external gas flowing from cosmic filaments. The gas is then intermittently driven to the galaxy center, to form nuclear starbursts and fuel an active nucleus. The various time-scales of these gaseous flows are described.

  20. Multiphase cooling flows

    E-Print Network [OSTI]

    Peter A. Thomas

    1996-08-20T23:59:59.000Z

    I discuss the multiphase nature of the intracluster medium whose neglect can lead to overestimates of the baryon fraction of clusters by up to a factor of two. The multiphase form of the cooling flow equations are derived and reduced to a simple form for a wide class of self-similar density distributions. It is shown that steady-state cooling flows are \\emph{not} consistent with all possible emissivity profiles which can therefore be used as a test of the theory. In combination, they provide strong constraints on the mass distribution within the cooling radius.

  1. Regional Variation in Residential Heat Pump Water Heater Performance...

    Energy Savers [EERE]

    Regional Variation in Residential Heat Pump Water Heater Performance in the United States Regional Variation in Residential Heat Pump Water Heater Performance in the United States...

  2. Turing patterns visualized by index of refraction variations

    SciTech Connect (OSTI)

    Lee, K.J.; McCormick, W.D.; Swinney, H.L. (Center for Nonlinear Dynamics and Department of Physics, The University of Texas, Austin, Texas 78712 (United States)); Noszticzius, Z. (Center for Nonlinear Dynamics and Department of Physics, The University of Texas, Austin, Texas 78712 (United States) Department of Chemical Physics, The Technical University of Budapest, H-1521, Budapest (Hungary))

    1992-03-01T23:59:59.000Z

    Gel pattern is visualized by the refractive index variations.The fossil patterns correspond to a spatial variation in the refractive index. (AIP)

  3. Opposed-flow virtual cyclone for particle concentration

    DOE Patents [OSTI]

    Rader, Daniel J. (Lafayette, CA); Torczynski, John R. (Albuquerque, NM)

    2000-12-05T23:59:59.000Z

    An opposed-flow virtual cyclone for aerosol collation which can accurately collect, classify, and concentrate (enrich) particles in a specific size range. The opposed-flow virtual cyclone is a variation on the virtual cyclone and has its inherent advantages (no-impact particle separation in a simple geometry), while providing a more robust design for concentrating particles in a flow-through type system. The opposed-flow virtual cyclone consists of two geometrically similar virtual cyclones arranged such that their inlet jets are inwardly directed and symmetrically opposed relative to a plane of symmetry located between the two inlet slits. A top plate bounds both jets on the "top" side of the inlets, while the other or lower wall curves "down" and away from each inlet jet. Each inlet jet will follow the adjacent lower wall as it turns away, and that particles will be transferred away from the wall and towards the symmetry plane by centrifugal action. After turning, the two jets merge smoothly along the symmetry line and flow parallel to it through the throat. Particles are transferred from the main flows, across a dividing streamline, and into a central recirculating region, where particle concentrations become greatly increased relative to the main stream.

  4. Temporally, spatially, and spectrally resolved barrier discharge produced in trapped helium gas at atmospheric pressure

    SciTech Connect (OSTI)

    Chiper, Alina Silvia; Popa, Gheorghe [Faculty of Physics, Alexandru Ioan Cuza University, 700506 Iasi (Romania)] [Faculty of Physics, Alexandru Ioan Cuza University, 700506 Iasi (Romania)

    2013-06-07T23:59:59.000Z

    Experimental study was made on induced effects by trapped helium gas in the pulsed positive dielectric barrier discharge (DBD) operating in symmetrical electrode configuration at atmospheric pressure. Using fast photography technique and electrical measurements, the differences in the discharge regimes between the stationary and the flowing helium are investigated. It was shown experimentally that the trapped gas atmosphere (TGA) has notable impact on the barrier discharge regime compared with the influence of the flowing gas atmosphere. According to our experimental results, the DBD discharge produced in trapped helium gas can be categorized as a multi-glow (pseudo-glow) discharge, each discharge working in the sub-normal glow regime. This conclusion is made by considering the duration of current pulse (few {mu}s), their maximum values (tens of mA), the presence of negative slope on the voltage-current characteristic, and the spatio-temporal evolution of the most representative excited species in the discharge gap. The paper focuses on the space-time distribution of the active species with a view to better understand the pseudo-glow discharge mechanism. The physical basis for these effects was suggested. A transition to filamentary discharge is suppressed in TGA mode due to the formation of supplementary source of seed electrons by surface processes (by desorption of electrons due to vibrationally excited nitrogen molecules, originated from barriers surfaces) rather than volume processes (by enhanced Penning ionisation). Finally, we show that the pseudo-glow discharge can be generated by working gas trapping only; maintaining unchanged all the electrical and constructive parameters.

  5. Flow cytometry apparatus

    DOE Patents [OSTI]

    Pinkel, Daniel (Walnut Creek, CA)

    1991-01-01T23:59:59.000Z

    An obstruction across the flow chamber creates a one dimensional convergence of a sheath fluid. A passageway in the construction directs flat cells near to the area of one dimensional convergence in the sheath fluid to provide proper orientation of flat cells at fast rates.

  6. AGN and Cooling Flows

    E-Print Network [OSTI]

    James Binney

    2001-03-23T23:59:59.000Z

    For two decades the steady-state cooling-flow model has dominated the literature of cluster and elliptical-galaxy X-ray sources. For ten years this model has been in severe difficulty from a theoretical point of view, and it is now coming under increasing pressure observationally. For two decades the steady-state cooling-flow model has dominated the literature of cluster and elliptical-galaxy X-ray sources. For ten years this model has been in severe difficulty from a theoretical point of view, and it is now coming under increasing pressure observationally. A small number of enthusiasts have argued for a radically different interpretation of the data, but had little impact on prevailing opinion because the unsteady heating picture that they advocate is extremely hard to work out in detail. Here I explain why it is difficult to extract robust observational predictions from the heating picture. Major problems include the variability of the sources, the different ways in which a bi-polar flow can impact on X-ray emission, the weakness of synchrotron emission from sub-relativistic flows, and the sensitivity of synchrotron emission to a magnetic field that is probably highly localized.

  7. Study of flow fields induced by surface dielectric barrier discharge actuator in low-pressure air

    SciTech Connect (OSTI)

    Che, Xueke, E-mail: chedk@163.com, E-mail: st@mail.iee.ac.cn; Nie, Wansheng; Tian, Xihui; Hou, Zhiyong; He, Haobo; Zhou, Penghui; Zhou, Siyin; Yang, Chao [Equipment Academy, Beijing 101416 (China)] [Equipment Academy, Beijing 101416 (China); Shao, Tao, E-mail: chedk@163.com, E-mail: st@mail.iee.ac.cn [Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190 (China)] [Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-04-15T23:59:59.000Z

    Surface dielectric barrier discharge (SDBD) is a promising method for a flow control. Flow fields induced by a SDBD actuator driven by the ac voltage in static air at low pressures varying from 1.0 to 27.7?kPa are measured by the particle image velocimetry method. The influence of the applied ac voltage frequency and magnitude on the induced flow fields is studied. The results show that three different classes of flow fields (wall jet flow field, complex flow field, and vortex-shape flow field) can be induced by the SDBD actuator in the low-pressure air. Among them, the wall jet flow field is the same as the tangential jet at atmospheric pressure, which is, together with the vertical jet, the complex flow field. The vortex-shape flow field is composed of one vertical jet which points towards the wall and two opposite tangential jets. The complex and the vortex-shape flow fields can be transformed to the wall jet flow field when the applied ac voltage frequency and magnitude are changed. It is found that the discharge power consumption increases initially, decreases, and then increases again at the same applied ac voltage magnitude when the air pressure decreases. The tangential velocity of the wall jet flow field increases when the air pressure decreases. It is however opposite for the complex flow field. The variation of the applied ac voltage frequency influences differently three different flow fields. When the applied ac voltage magnitude increases at the same applied ac voltage frequency, the maximal jet velocity increases, while the power efficiency increases only initially and then decreases again. The discharge power shows either linear or exponential dependences on the applied ac voltage magnitude.

  8. Berry and others: Temporal Trends of Canopy-forming Kelp Beds Temporal Trends in the Areal Extent of Canopy-forming

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Berry and others: Temporal Trends of Canopy-forming Kelp Beds Temporal Trends in the Areal Extent of Canopy-forming Kelp Beds Along the Strait of Juan de Fuca and Washington's Outer Coast Helen Berry Ecoscan Resource Data Extended Abstract Kelp beds are important nearshore habitats that support commercial

  9. Decadal-scale variations in ice flow along Whillans Ice Stream and its tributaries, West Antarctica

    E-Print Network [OSTI]

    Stearns, Leigh; Jezek, K.A.; Van der Veen, C.J.

    2005-01-01T23:59:59.000Z

    We investigate velocity changes occurring along Whillans Ice Stream (WIS) by comparing velocities derived from repeat aerial photographs acquired in 1985–89 (average date of 1987) to interferometric satellite radar (InSAR) velocities collected...

  10. Transient response of an industrial fin tube heat exchanger to flow variations

    E-Print Network [OSTI]

    Rana, Gopalji Motiram

    1967-01-01T23:59:59.000Z

    . Tho most impor ant assumptions made were that the proper- tiess Gl. t t e s Leais ar!d w, !ter and heat transfer coe f f ic ients for the stean! and water side did not vary with posi ion. l, spies: transform techniques were utilized to obtain the...

  11. VARIATIONAL MULTISCALE FINITE ELEMENT METHOD FOR FLOWS IN HIGHLY POROUS MEDIA

    E-Print Network [OSTI]

    Lazarov, Raytcho

    to 99.7 % (see Figure 1.1(a)) and industrial foams with porosity up to 95% (see Figure 1.1(b)). In order in heterogeneous media is a difficult task which up to now is not fully mastered. (a) Glass wool

  12. Coupling free flow / porous-medium flow General idea

    E-Print Network [OSTI]

    Cirpka, Olaf Arie

    equation t (v) + div (vv ) - div(v) + p - g - qv = 0 Darcy flow equation t (S) - div K (p - g) - qpmT transport equation t (X) + div (vX - DsteamX) = qsteam 16/14 #12;Backup additional Darcy flow equations-Stokes 1 phase, 2 components, temperature sharp interface porous-medium / Darcy flow 2 phases, 2 component

  13. Gaussian variational ansatz in the problem of anomalous sea waves: Comparison with direct numerical simulations

    E-Print Network [OSTI]

    Ruban, V P

    2015-01-01T23:59:59.000Z

    The nonlinear dynamics of an obliquely oriented wave packet at sea surface is studied both analytically and numerically for various initial parameters of the packet, in connection with the problem of oceanic rogue waves. In the framework of Gaussian variational ansatz applied to the corresponding (1+2D) hyperbolic nonlinear Schr\\"odinger equation, a simplified Lagrangian system of differential equations is derived, which determines the evolution of coefficients of the real and imaginary quadratic forms appearing in the Gaussian. This model provides a semi-quantitative description for the process of nonlinear spatio-temporal focusing, which is one of the most probable mechanisms of rogue wave formation in random wave fields. The system is integrated in quadratures, which fact allows us to understand qualitative differences between the linear and nonlinear regimes of the focusing of wave packet. Comparison of the Gaussian model predictions with results of direct numerical simulation of fully nonlinear long-cres...

  14. The effects of variations in the photocathode voltages of electronic streak cameras

    SciTech Connect (OSTI)

    Bowers, M.W.; Biggs, G.L.; Ronchetto, J.J.; Teruya, A.T.

    1988-08-08T23:59:59.000Z

    Electronic streak cameras are used to record subnanosecond data at the Nevada Test Site. It has been found that externally induced variations in the photocathode voltage of the streak tube can produce both temporal and spatial errors on the output image. An electron beam tracing code was used to model the magnification as a function of photocathode voltage and signal input position for streak tubes manufactured by RCA, ITT, and Kentech. Laboratory tests were also performed where pulsed and radio frequency signals were induced upon the photocathode and the errors on the resultant image were compared with the error predicted by the electron beam code. Also, methods for processing the distortion in digitized images were investigated. This paper will discuss the results of these investigations. 3 refs., 17 figs.

  15. Message Flow Modulator Final Report

    E-Print Network [OSTI]

    Boyer, Robert Stephen

    operational environment at the Patuxent River Naval Air Test Center with scenarios developed by an independent in testing and demonstrating the flow modulator at the Patuxent River Naval Air Test Center. #12;MESSAGE FLOW

  16. Radial flow pulse jet mixer

    DOE Patents [OSTI]

    VanOsdol, John G.

    2013-06-25T23:59:59.000Z

    The disclosure provides a pulse jet mixing vessel for mixing a plurality of solid particles. The pulse jet mixing vessel is comprised of a sludge basin, a flow surface surrounding the sludge basin, and a downcoming flow annulus between the flow surface and an inner shroud. The pulse jet mixing vessel is additionally comprised of an upper vessel pressurization volume in fluid communication with the downcoming flow annulus, and an inner shroud surge volume separated from the downcoming flow annulus by the inner shroud. When the solid particles are resting on the sludge basin and a fluid such as water is atop the particles and extending into the downcoming flow annulus and the inner shroud surge volume, mixing occurs by pressurization of the upper vessel pressurization volume, generating an inward radial flow over the flow surface and an upwash jet at the center of the sludge basin.

  17. Flow (2008) Director: Irena Salina

    E-Print Network [OSTI]

    Hemmers, Oliver

    2008-01-01T23:59:59.000Z

    Flow (2008) Director: Irena Salina Run Time: 93 min. Summary: ,Irena Salina's documentary film://documentaryfilms.suite101.com/article.cfm/desperate_for_water_irena_salinas_movie_flow No Dumb Questions (2001) Director

  18. Fractional Variational Iteration Method for Fractional Nonlinear Differential Equations

    E-Print Network [OSTI]

    Guo-cheng Wu

    2010-07-12T23:59:59.000Z

    Recently, fractional differential equations have been investigated via the famous variational iteration method. However, all the previous works avoid the term of fractional derivative and handle them as a restricted variation. In order to overcome such shortcomings, a fractional variational iteration method is proposed. The Lagrange multipliers can be identified explicitly based on fractional variational theory.

  19. Controlled Flow of Spin-Entangled Electrons via Adiabatic Quantum Pumping

    E-Print Network [OSTI]

    Kunal K. Das; Sungjun Kim; Ari Mizel

    2005-06-21T23:59:59.000Z

    We propose a method to dynamically generate and control the flow of spin-entangled electrons, each belonging to a spin-singlet, by means of adiabatic quantum pumping. The pumping cycle functions by periodic time variation of localized two-body interactions. We develop a generalized approach to adiabatic quantum pumping as traditional methods based on scattering matrix in one dimension cannot be applied here. We specifically compute the flow of spin-entangled electrons within a Hubbard-like model of quantum dots, and discuss possible implementations and identify parameters that can be used to control the singlet flow.

  20. Streamline topology and dilute particle dynamics in a Karman vortex street flow

    E-Print Network [OSTI]

    Wu, Z B

    2003-01-01T23:59:59.000Z

    Three types of streamline topology in a Karman vortex street flow are shown under the variation of spatial parameters. For the motion of dilute particles in the K\\'arm\\'an vortex street flow, there exist a route of bifurcation to a chaotic orbit and more attractors in a bifurcation diagram for the proportion of particle density to fluid density. Along with the increase of spatial parameters in the flow filed, the bifurcation process is suspended, as well as more and more attractors emerge. In the motion of dilute particles, a drag term and gravity term dominate and result in the bifurcation phenomenon.

  1. Photon temporal modes: a complete framework for quantum information science

    E-Print Network [OSTI]

    B. Brecht; Dileep V. Reddy; C. Silberhorn; M. G. Raymer

    2015-04-23T23:59:59.000Z

    Temporal modes (TMs) of photonic quantum states provide promising bases for quantum information science (QIS), because they intrinsically span a high-dimensional Hilbert space and lend themselves to integration into existing single-mode fiber communication networks. We show that the three main requirements to construct a valid framework for QIS - the controlled generation of resource states, the targeted and highly efficient manipulation of TMs and their efficient detection, can be fulfilled with current technology. We suggest implementations of diverse QIS applications based on those three building blocks.

  2. Single-shot 35 fs temporal resolution electron shadowgraphy

    SciTech Connect (OSTI)

    Scoby, C. M.; Li, R. K.; Threlkeld, E.; To, H.; Musumeci, P. [Department of Physics and Astronomy, UCLA, Los Angeles, California 90095 (United States)] [Department of Physics and Astronomy, UCLA, Los Angeles, California 90095 (United States)

    2013-01-14T23:59:59.000Z

    We obtain single-shot time-resolved shadowgraph images of the electromagnetic fields resulting from the interaction of a high intensity ultrashort laser pulse with a metal surface. Using a high brightness relativistic electron beam and a high streaking speed radiofrequency deflector, we report <35 fs temporal resolution enabling a direct visualization of the retarded-time dominated field evolution which follows the laser-induced charge emission. A model including the finite signal propagation speed well reproduces the data and yields measurements of fundamental parameters in short pulse laser-matter interaction such as the amount of emitted charge and the emission time scale.

  3. Ricci flow and quantum theory

    E-Print Network [OSTI]

    Robert Carroll

    2007-11-05T23:59:59.000Z

    We show some relations between Ricci flow and quantum theory via Fisher information and the quantum potential.

  4. Progress in Grid Scale Flow Batteries

    E-Print Network [OSTI]

    2011Year #12;Flow Battery Research at PNNL and Sandia #12 with industries and universities New Generation Redox Flow Batteries, PNNL Developed new generation redox flow

  5. 2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSSIMIC) M07-4 Myocardial Blood Flow from Dynamic PET

    E-Print Network [OSTI]

    Duncan, James S.

    -4 Myocardial Blood Flow from Dynamic PET using Independent Component Analysis Alexander Karpikov, Hemant Tagare) from dynamic PET requires a reproducible and reliable method to obtain left and right ventricular time-activity curves. We propose the use of Independent Component Analysis (ICA) on PET temporal information to segment

  6. Helium and Deuterium Abundances as a Test for the Time Variation of the Fine Structure Constant and the Higgs Vacuum Expectation Value

    E-Print Network [OSTI]

    Nidal Chamoun; Susana J. Landau; Mercedes E. Mosquera; Hector Vucetich

    2006-12-21T23:59:59.000Z

    We use the semi-analytic method of \\citet{Esma91} to calculate the abundances of Helium and Deuterium produced during Big Bang nucleosynthesis assuming the fine structure constant and the Higgs vacuum expectation value may vary in time. We analyze the dependence on the fundamental constants of the nucleon mass, nuclear binding energies and cross sections involved in the calculation of the abundances. Unlike previous works, we do not assume the chiral limit of QCD. Rather, we take into account the quark masses and consider the one-pion exchange potential, within perturbation theory, for the proton-neutron scattering. However, we do not consider the time variation of the strong interactions scale but attribute the changes in the quark masses to the temporal variation of the Higgs vacuum expectation value. Using the observational data of the helium and deuterium, we put constraints on the variation of the fundamental constants between the time of nucleosynthesis and the present time.

  7. The Big Flow

    E-Print Network [OSTI]

    P. Sikivie

    2001-12-04T23:59:59.000Z

    The late infall of cold dark matter onto an isolated galaxy, such as our own, produces streams and caustics in its halo. The outer caustics are topological spheres whereas the inner caustics are rings. The self-similar model of galactic halo formation predicts that the caustic ring radii $a_n$ follow the approximate law $a_n \\sim 1/n$. In a study of 32 extended and well-measured external galactic rotation curves evidence was found for this law. In the case of the Milky Way, the locations of eight sharp rises in the rotation curve fit the prediction of the self-similar model at the 3% level. Moreover, a triangular feature in the IRAS map of the galactic plane is consistent with the imprint of a ring caustic upon the baryonic matter. These observations imply that the dark matter in our neighborhood is dominated by a single flow. Estimates of that flow's density and velocity vector are given.

  8. Structural power flow measurement

    SciTech Connect (OSTI)

    Falter, K.J.; Keltie, R.F.

    1988-12-01T23:59:59.000Z

    Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

  9. Momentum and heat fluxes in a turbulent air flow over a wet, smooth boundary

    E-Print Network [OSTI]

    Rice, Warren

    1958-01-01T23:59:59.000Z

    Idealized sketch, of boundary layer flow regions................ .............45 Figure 2 Schematic diagram of wind tunnel. . . . 46 Figure 3 Photograph of wind tunnel............ .. 47 Figure 4 Photograph of wind tunnel............ .. 47 Figure 5... mechanism and probe.................. .. 49 Figure 9 Distances of interest in the momentum and thermal boundary layers ............ 50 Figure 10 A typical velocity and temperature profile comparison .................. .. 51 Figure 1 1 Variation...

  10. Convective heat flow probe

    DOE Patents [OSTI]

    Dunn, J.C.; Hardee, H.C.; Striker, R.P.

    1984-01-09T23:59:59.000Z

    A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

  11. Variational Gaussian Process Classifiers Mark N. Gibbs

    E-Print Network [OSTI]

    MacKay, David J.C.

    Variational Gaussian Process Classifiers Mark N. Gibbs Cavendish Laboratory Cambridge CB3 0HE United Kingdom David J.C. MacKay \\Lambda Cavendish Laboratory Cambridge CB3 0HE United Kingdom Submitted­linear interpolation tool (Williams 1995; Williams and Rasmussen 1996), but it is not straightforward to solve

  12. Learning Contextual Variations for Video Segmentation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Learning Contextual Variations for Video Segmentation Vincent Martin and Monique Thonnat INRIA.R.Martin, Monique.Thonnat}@sophia.inria.fr, http://www-sop.inria.fr/pulsar/ Abstract. This paper deals with video-illumination changes and long term changes are present. In this situation, the major difficulty at the segmentation

  13. A Variational Approach to MR Bias Correction

    E-Print Network [OSTI]

    Willsky, Alan S.

    A Variational Approach to MR Bias Correction Ayres Fan Stochastic Systems Group July 17, 2003 With W. Wells, J. Fisher, M. Cetin, S. Haker, R. Mulkern, C. Tempany, A. Willsky #12;Outline 1 inhomogeneity that corrupts magnetic resonance (MR) images. Correcting for the bias field makes both human

  14. A Variational Approach to MR Bias Correction

    E-Print Network [OSTI]

    Willsky, Alan S.

    sequences, the MR signal is given by: We can target , T1, and T2 measurements through appropriate selectionA Variational Approach to MR Bias Correction Ayres Fan Stochastic Systems Group Research Qualifying Exam June 10, 2003 #12;Outline 1. Introduction to bias correction 2. Magnetic resonance imaging 3

  15. A Variational Approach to MR Bias Correction

    E-Print Network [OSTI]

    Willsky, Alan S.

    A Variational Approach to MR Bias Correction Ayres Fan, W. Wells, J. Fisher, M. Cetin, S. Haker, A that corrupts magnetic resonance (MR) images. Correcting for the bias field makes both human analysis (e that encourages smoothness in b and piecewise smoothness in f: We generally choose p 1 to help preserve edges D

  16. Spatial Vision Sensitivity to Color Variations

    E-Print Network [OSTI]

    Majumder, Aditi

    ;Sensitivity to Color Variations · Why is sunlit sky blue? · Why is sunrise/sunset red? 2 #12;Color vision with luminance contrast 6 #12;Pure Color Gratings · Differences in the cone responses to the same patterns a pattern which varies in chromaticity but which is constant in luminance across its extent · Inphase

  17. A modified variational approach to scattering

    E-Print Network [OSTI]

    Parnell, Gregory Elliott

    1978-01-01T23:59:59.000Z

    , 11'-99 -C. ', i493 Q I; 49". , 0 ;Q594 -0. 105&34 1CSoc TABLE III. phase shiftstl for single'. p-wave electron scattering from H calculated by the modi- fied variational method (with second basis function peak at 1/2). H is the number of basis...

  18. Variational Methods in Combinatorial Optimization and

    E-Print Network [OSTI]

    Jönsson, Henrik

    ¨onsson Department of Theoretical Physics Lund University, Sweden Thesis for the degree of Doctor of Philosophy of the Faculty of Mathematics and Natural Sciences of Lund University, for public criticism in Lecture Hall F features of a gas, or a solid compound. The variational approach is used to approximate the behavior

  19. Variational functions in degenerate open quantum systems

    SciTech Connect (OSTI)

    Jakob, Matthias; Stenholm, Stig [Laser Physics and Quantum Optics, Royal Institute of Technology (KTH), Alba Nova, Roslagstullsbacken 21, SE-10691 Stockholm (Sweden)

    2004-04-01T23:59:59.000Z

    We have derived a Lyapunov functional for a degenerate open atomic system. This functional develops monotonically towards its stationary state. The open system is described by a Lindblad-type master equation. For the construction of the variational functional it is necessary that the Lindblad operator can be diagonalized. Since the generator of motion is non-Hermitian, diagonalization is, in general, only possible if the eigenvalues are nondegenerate. In this paper, we propose that in a physical system the biorthogonal eigenbasis of the Lindblad operator remains complete even when degeneracy is present. Thus diagonalization of the Lindblad operator, and consequently the construction of the variational functional, is still possible. We discuss the reasons and illustrate the theory of the variational functional for a driven {lambda}-type three-level atom with degenerate ground state. The degeneracy has interesting effects on the variational functional in the steady state with respect to its interpretation as an entropic quantity. In case of the driven three-level atom, the dark state turns out to be an isentropic state.

  20. Temporally and spatially resolved characterization of microwave induced argon plasmas: Experiment and modeling

    SciTech Connect (OSTI)

    Baeva, M., E-mail: baeva@inp-greifswald.de; Andrasch, M.; Ehlbeck, J.; Loffhagen, D.; Weltmann, K.-D. [INP Greifswald, Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany)

    2014-04-14T23:59:59.000Z

    Experiments and modeling of the plasma-microwave interaction have been performed in a coaxial microwave plasma source at a field frequency of 2.45 GHz generating argon plasmas at pressures of 20 and 40 millibars and a ratio of flow rate to pressure of 0.125 sccm/Pa. The incident microwave power between 100?W and 300?W is supplied in a regime of a pulse-width modulation with cycle duration of 110?ms and a power-on time of 23?ms. The experiments are based on heterodyne reflectometry and microwave interferometry at 45.75?GHz. They provide the temporal behaviour of the complex reflection coefficient, the microwave power in the plasma, as well as the electron density in the afterglow zone of the discharge. The self-consistent spatially two-dimensional and time-dependent modeling complements the analysis of the plasma-microwave interaction delivering the plasma and electromagnetic field parameters. The consolidating experimental observations and model predictions allow further characterizing the plasma source. The generated plasma has a core occupying the region close to the end of the inner electrode, where maximum electron densities above 10{sup 20}?m{sup ?3} and electron temperatures of about 1?eV are observed. Due to a longer outer electrode of the coaxial structure, the plasma region is extended and fills the volume comprised by the outer electrode. The electron density reaches values of the order of 10{sup 19}?m{sup ?3}. The heating of the gas occurs in its great part due to elastic collisions with the plasma electrons. However, the contribution of the convective heating is important especially in the extended plasma region, where the gas temperature reaches its maximum values up to approximately 1400?K. The temporally and spatially resolved modeling enables a thorough investigation of the plasma-microwave interaction which clearly shows that the power in-coupling occurs in the region of the highest electron density during the early stage of the discharge. In the steady state phase, however, the power in-coupling occurs close to the source walls where the electron density is significantly lower than on the discharge axis.

  1. Composition pulse time-of-flight mass flow sensor

    DOE Patents [OSTI]

    Harnett, Cindy K. (Livermore, CA); Crocker, Robert W. (Fremont, CA); Mosier, Bruce P. (San Francisco, CA); Caton, Pamela F. (Berkeley, CA); Stamps, James F. (Livermore, CA)

    2007-06-05T23:59:59.000Z

    A device for measuring fluid flow rates over a wide range of flow rates (<1 nL/min to >10 .mu.L/min) and at pressures at least as great as 2,000 psi. The invention is particularly adapted for use in microfluidic systems. The device operates by producing compositional variations in the fluid, or pulses, that are subsequently detected downstream from the point of creation to derive a flow rate. Each pulse, comprising a small fluid volume, whose composition is different from the mean composition of the fluid, can be created by electrochemical means, such as by electrolysis of a solvent, electrolysis of a dissolved species, or electrodialysis of a dissolved ionic species. Measurements of the conductivity of the fluid can be used to detect the arrival time of the pulses, from which the fluid flow rate can be determined. A pair of spaced apart electrodes can be used to produce the electrochemical pulse. In those instances where it is desired to measure a wide range of fluid flow rates a three electrode configuration in which the electrodes are spaced at unequal distances has been found to be desirable.

  2. Unstructured spectral element methods of simulation of turbulent flows

    SciTech Connect (OSTI)

    Henderson, R.D. [California Inst. of Technology, Pasadena, CA (United States)] [California Inst. of Technology, Pasadena, CA (United States); Karniadakis, G.E. [Brown Univ., Providence, RI (United States)] [Brown Univ., Providence, RI (United States)

    1995-12-01T23:59:59.000Z

    In this paper we present a spectral element-Fourier algorithm for simulating incompressible turbulent flows in complex geometries using unstructured quadrilateral meshes. To this end, we compare two different interface formulations for extending the conforming spectral element method in order to allow for surgical mesh refinement and still retain spectral accuracy: the Zanolli iterative procedure and variational patching based on auxiliary {open_quotes}mortar{close_quotes} functions. We present an interpretation of the original mortar element method as a patching scheme and develop direct and iterative solution techniques that make the method efficient for simulations of turbulent flows. The properties of the new method are analyzed in detail by studying the eigenspectra of the advection and diffusion operators. We then present numerical results that illustrate the flexibility as well as the exponential convergence of the new algorithm for nonconforming discretizations. We conclude with simulation studies of the turbulent cylinder wake at Re = 1000 (external flow) and turbulent flow over riblets at Re = 3280 (internal flow). 36 refs., 29 figs., 7 tabs.

  3. Generalized Solovev equilibrium with sheared flow of arbitrary direction and stability consideration

    SciTech Connect (OSTI)

    Kaltsas, D. A., E-mail: dkaltsas@cc.uoi.gr, E-mail: gthroum@cc.uoi.gr; Throumoulopoulos, G. N., E-mail: dkaltsas@cc.uoi.gr, E-mail: gthroum@cc.uoi.gr [Department of Physics, University of Ioannina, GR 451 10 Ioannina (Greece)

    2014-08-15T23:59:59.000Z

    A Solovev-like solution describing equilibria with field aligned incompressible flows [G. N. Throumoulopoulos and H. Tasso, Phys. Plasmas 19, 014504 (2012)] is extended to non parallel flows. The solution expressed as a superposition of Bessel functions contains an arbitrary number of free parameters which are exploited to construct a variety of configurations including ITER shaped ones. For parallel flows, application of a sufficient condition for linear stability shows that this condition is satisfied in an appreciable part of the plasma region on the high-field side mostly due to the variation of the magnetic field perpendicular to the magnetic surfaces. Also, the results indicate that depending on the shape of the Mach-function profile and the values of the free parameters the flow and flow shear may have either stabilizing or destabilizing effects.

  4. Advanced tomographic flow diagnostics for opaque multiphase fluids

    SciTech Connect (OSTI)

    Torczynski, J.R.; O`Hern, T.J.; Adkins, D.R.; Jackson, N.B.; Shollenberger, K.A.

    1997-05-01T23:59:59.000Z

    This report documents the work performed for the ``Advanced Tomographic Flow Diagnostics for Opaque Multiphase Fluids`` LDRD (Laboratory-Directed Research and Development) project and is presented as the fulfillment of the LDRD reporting requirement. Dispersed multiphase flows, particularly gas-liquid flows, are industrially important to the chemical and applied-energy industries, where bubble-column reactors are employed for chemical synthesis and waste treatment. Due to the large range of length scales (10{sup {minus}6}-10{sup 1}m) inherent in real systems, direct numerical simulation is not possible at present, so computational simulations are forced to use models of subgrid-scale processes, the accuracy of which strongly impacts simulation fidelity. The development and validation of such subgrid-scale models requires data sets at representative conditions. The ideal measurement techniques would provide spatially and temporally resolved full-field measurements of the distributions of all phases, their velocity fields, and additional associated quantities such as pressure and temperature. No technique or set of techniques is known that satisfies this requirement. In this study, efforts are focused on characterizing the spatial distribution of the phases in two-phase gas-liquid flow and in three-phase gas-liquid-solid flow. Due to its industrial importance, the bubble-column geometry is selected for diagnostics development and assessment. Two bubble-column testbeds are utilized: one at laboratory scale and one close to industrial scale. Several techniques for measuring the phase distributions at conditions of industrial interest are examined: level-rise measurements, differential-pressure measurements, bulk electrical impedance measurements, electrical bubble probes, x-ray tomography, gamma-densitometry tomography, and electrical impedance tomography.

  5. Improving microbial fitness in the mammalian gut by in vivo temporal functional metagenomics

    E-Print Network [OSTI]

    Yaung, Stephanie J.

    Elucidating functions of commensal microbial genes in the mammalian gut is challenging because many commensals are recalcitrant to laboratory cultivation and genetic manipulation. We present Temporal FUnctional Metagenomics ...

  6. analyze label-free temporal: Topics by E-print Network

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

    silicon waveguides in the presence of two-photon absorption, free-carrier dispersion and free-carrier absorption. The evolution equations for pulse energy, temporal position,...

  7. Embedded Temporal Difference in Life Cycle Assessment: Case Study on VW Golf A4 Car

    E-Print Network [OSTI]

    Yuan, Chris; Simon, Rachel; Natalie Mady; Dornfeld, David

    2009-01-01T23:59:59.000Z

    may alter Life Cycle Assessment (LCA) results that wereLife Cycle Impact Assessment,” International Journal of LCAsystem for life cycle assessment. The LCA temporal space

  8. Complex Flow Workshop Report

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the YouTube platformBuildingCoalComplex Flow Workshop Report January 17-18, 2012 University

  9. Non-axisymmetric Flows

    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's Possible for Renewable Energy:Nanowire Solar541,9337,2AprilBig EddyNobelNon-axisymmetric Flows and

  10. Unusual Congenital Aortic Anomaly with Rare Common Celiamesenteric Trunk Variation: MR Angiography and Digital Substraction Angiography Findings

    SciTech Connect (OSTI)

    Tosun, Ozgur [Ankara Ataturk Education and Research Hospital, Department of Radiology (Turkey)], E-mail: ztosun@yahoo.com; Sanlidilek, Umman [Ankara University School of Medicine, Department of Radiology (Turkey); Cetin, Huseyin [Ankara Ataturk Education and Research Hospital, Department of Radiology (Turkey); Ozdemir, Ozcan [Ankara Akay Hospital, Department of Cardiology (Turkey); Kurt, Aydin; Sakarya, Mehmet Emin; Tas, Ismet [Ankara Ataturk Education and Research Hospital, Department of Radiology (Turkey)

    2007-09-15T23:59:59.000Z

    Magnetic resonance angiography and digital substraction angiography (DSA) findings in a case with a rare congenital thoracoabdominal aortic hypoplasia and common celiamesenteric trunk variation with occlusion of infrarenal abdominal aorta are described here. To our knowledge, this aortic anomaly has not been previously described in the English literature. DSA is the optimum imaging modality for determination of aortic hypoplasia, associated vascular malformations, collateral vessels, and direction of flow within vessels.

  11. On seismic signatures of rapid variation

    E-Print Network [OSTI]

    G. Houdek; D. O. Gough

    2006-12-01T23:59:59.000Z

    We present an improved model for an asteroseismic diagnostic contained in the frequency spacing of low-degree acoustic modes. By modelling in a realistic manner regions of rapid variation of dynamically relevant quantities, which we call acoustic glitches, we can derive signatures of the gross properties of those glitches. In particular, we are interested in measuring properties that are related to the helium ionization zones and to the rapid variation in the background state associated with the lower boundary of the convective envelope. The formula for the seismic diagnostic is tested against a sequence of theoretical models of the Sun, and is compared with seismic diagnostics published previously by Monteiro & Thompson (1998, 2005) and by Basu et al. (2004).

  12. Large Matched-Index-of-Refraction (MIR) Flow Systems for International Collaboration In Fluid Mechanics

    SciTech Connect (OSTI)

    Donald M. McEligot; Stefan Becker; Hugh M. McIlroy, Jr.

    2010-07-01T23:59:59.000Z

    In recent international collaboration, INL and Uni. Erlangen have developed large MIR flow systems which can be ideal for joint graduate student education and research. The benefit of the MIR technique is that it permits optical measurements to determine flow characteristics in complex passages and around objects to be obtained without locating a disturbing transducer in the flow field and without distortion of the optical paths. The MIR technique is not new itself; others employed it earlier. The innovation of these MIR systems is their large size relative to previous experiments, yielding improved spatial and temporal resolution. This report will discuss the benefits of the technique, characteristics of the systems and some examples of their applications to complex situations. Typically their experiments have provided new fundamental understanding plus benchmark data for assessment and possible validation of computational thermal fluid dynamic codes.

  13. Systems for controlling the intensity variations in a laser beam and for frequency conversion thereof

    DOE Patents [OSTI]

    Skupsky, Stanley (Rochester, NY); Craxton, R. Stephen (Rochester, NY); Soures, John (Pittsford, NY)

    1990-01-01T23:59:59.000Z

    In order to control the intensity of a laser beam so that its intensity varies uniformly and provides uniform illumination of a target, such as a laser fusion target, a broad bandwidth laser pulse is spectrally dispersed spatially so that the frequency components thereof are spread apart. A disperser (grating) provides an output beam which varies spatially in wavelength in at least one direction transverse to the direction of propagation of the beam. Temporal spread (time delay) across the beam is corrected by using a phase delay device (a time delay compensation echelon). The dispersed beam may be amplified with laser amplifiers and frequency converted (doubled, tripled or quadrupled in frequency) with nonlinear optical elements (birefringent crystals). The spectral variation across the beam is compensated by varying the angle of incidence on one of the crystals with respect to the crystal optical axis utilizing a lens which diverges the beam. Another lens after the frequency converter may be used to recollimate the beam. The frequency converted beam is recombined so that portions of different frequency interfere and, unlike interference between waves of the same wavelength, there results an intensity pattern with rapid temoral oscillations which average out rapidly in time thereby producing uniform illumination on target. A distributed phase plate (also known as a random phase mask), through which the spectrally dispersed beam is passed and then focused on a target, is used to provide the interference pattern which becomes nearly modulation free and uniform in intensity in the direction of the spectral variation.

  14. Optimal Control of Evolution Mixed Variational Inclusions

    SciTech Connect (OSTI)

    Alduncin, Gonzalo, E-mail: alduncin@geofisica.unam.mx [Universidad Nacional Autónoma de México, Departamento de Recursos Naturales, Instituto de Geofísica (Mexico)

    2013-12-15T23:59:59.000Z

    Optimal control problems of primal and dual evolution mixed variational inclusions, in reflexive Banach spaces, are studied. The solvability analysis of the mixed state systems is established via duality principles. The optimality analysis is performed in terms of perturbation conjugate duality methods, and proximation penalty-duality algorithms to mixed optimality conditions are further presented. Applications to nonlinear diffusion constrained problems as well as quasistatic elastoviscoplastic bilateral contact problems exemplify the theory.

  15. Detection and quantitation of single nucleotide polymorphisms, DNA sequence variations, DNA mutations, DNA damage and DNA mismatches

    SciTech Connect (OSTI)

    McCutchen-Maloney, Sandra L. (Pleasanton, CA)

    2002-01-01T23:59:59.000Z

    DNA mutation binding proteins alone and as chimeric proteins with nucleases are used with solid supports to detect DNA sequence variations, DNA mutations and single nucleotide polymorphisms. The solid supports may be flow cytometry beads, DNA chips, glass slides or DNA dips sticks. DNA molecules are coupled to solid supports to form DNA-support complexes. Labeled DNA is used with unlabeled DNA mutation binding proteins such at TthMutS to detect DNA sequence variations, DNA mutations and single nucleotide length polymorphisms by binding which gives an increase in signal. Unlabeled DNA is utilized with labeled chimeras to detect DNA sequence variations, DNA mutations and single nucleotide length polymorphisms by nuclease activity of the chimera which gives a decrease in signal.

  16. Magnetospheric response to solar wind variations

    SciTech Connect (OSTI)

    Bargatze, L.F.; Baker, D.N.; McPherron, R.L.

    1985-04-01T23:59:59.000Z

    The time lagged response of the magnetosphere to solar wind variations has been determined using the linear prediction filtering method and 34 intervals of high time resolution IMP-8 solar wind data and auroral electrojet AL index data. The linear prediction filtering method is a powerful time series analysis technique which is utilized to produce a filter of time lagged response coefficients which estimates the most general linear relationship between magnetospheric activity and solar wind variations. This study uses the AL index to monitor the magnetosphere's response and VB/sub s/ to monitor the solar wind input. Before analysis, the median value of the AL index for each of the 34 intervals was utilized to rank the intervals according to the level of geomagnetic activity. It is found that the VB/sub s/-AL filters are composed of two response pulses peaking at time lags of 20-minutes and 60-minutes. Our interpretation associates the 20-minute pulse with activity driven directly by solar wind-magnetosphere interaction and it associates the 60-minute pulse with activity driven by the release of stored energy from the magnetotail. Thus, the filter results suggest that both the directly driven and the unloading models of magnetospheric response are important in describing the time lagged response of the magnetosphere to solar wind variations. 11 refs., 3 figs.

  17. A Decidable Timeout based Extension of Propositional Linear Temporal Logic

    E-Print Network [OSTI]

    Misra, Janardan

    2010-01-01T23:59:59.000Z

    We develop a timeout based extension of propositional linear temporal logic (which we call TLTL) to specify timing properties of timeout based models of real time systems. TLTL formulas explicitly refer to a running global clock together with static timing variables as well as a dynamic variable abstracting the timeout behavior. We extend LTL with the capability to express timeout constraints. From the expressiveness view point, TLTL is not comparable with important known clock based real-time logics including TPTL, XCTL, and MTL, i.e., TLTL can specify certain properties, which cannot be specified in these logics (also vice-versa). We define a corresponding timeout tableau for satisfiability checking of the TLTL formulas. Also a model checking algorithm over timeout Kripke structure is presented. Further we prove that the validity checking for such an extended logic remains PSPACE-complete even in the presence of timeout constraints and infinite state models. Under discrete time semantics, with bounded timeo...

  18. Unsupervised Learning in Networks of Spiking Neurons Using Temporal Coding

    E-Print Network [OSTI]

    1997-01-01T23:59:59.000Z

    . We propose a mechanism for unsupervised learning in networks of spiking neurons which is based on the timing of single firing events. Our results show that a topology preserving behaviour quite similar to that of Kohonen's self-organizing map can be achieved using temporal coding. In contrast to previous approaches, which use rate coding, the winner among competing neurons can be determined fast and locally. Hence our model is a further step towards a more realistic description of unsupervised learning in biological neural systems. 1 Introduction In the area of modelling information processing in biological neural systems, there is an ongoing debate about which essentials have to be taken into account (see e.g. [3,13,11,9]). Discrete models, such as threshold gates or McCullochPitts neurons, are undoubtedly very simplistic descriptions of biological neurons. Models with real-valued output, such as the sigmoidal gate, where analogue values are interpreted as firing rates of biologica...

  19. Temporal Profiles and Spectral Lags of XRF 060218

    E-Print Network [OSTI]

    Liang, E W; Stamatikos, M; Zhang, B; Norris, J; Gehrels, N; Zhang, J; Dai, Z G; Liang, En-Wei; Zhang, Bin-Bin; Stamatikos, Mike; Zhang, Bing; Norris, Jay; Gehrels, Neil; Zhang, Jin

    2006-01-01T23:59:59.000Z

    The spectral and temporal properties of the non-thermal emission ofthe nearby XRF 060218 in 0.3-150 keV band are studied. We show that both the spectral energy distribution and the light curve properties suggest the same origin of the non-thermal emission detected by {\\em Swift} BAT and XRT. This event has the longest pulse duration and spectral lag observed to date among the known GRBs. The pulse structure and its energy dependence are analogous to typical GRBs. By extrapolating the observed spectral lag to the {\\em CGRO/BATSE} bands we find that the hypothesis that this event complies with the same luminosity-lag relation with bright GRBs cannot be ruled out at $2\\sigma$ significance level. These intriguing facts, along with its compliance with the Amati-relation, indicate that XRF 060218 shares the similar radiation physics as typical GRBs.

  20. Fluid flow monitoring device

    DOE Patents [OSTI]

    McKay, M.D.; Sweeney, C.E.; Spangler, B.S. Jr.

    1993-11-30T23:59:59.000Z

    A flow meter and temperature measuring device are described comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips. 7 figures.

  1. Fluid flow monitoring device

    DOE Patents [OSTI]

    McKay, Mark D. (1426 Socastee Dr., North Augusta, SC 29841); Sweeney, Chad E. (3600 Westhampton Dr., Martinez, GA 30907-3036); Spangler, Jr., B. Samuel (2715 Margate Dr., Augusta, GA 30909)

    1993-01-01T23:59:59.000Z

    A flow meter and temperature measuring device comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips.

  2. Radial flow heat exchanger

    DOE Patents [OSTI]

    Valenzuela, Javier (Hanover, NH)

    2001-01-01T23:59:59.000Z

    A radial flow heat exchanger (20) having a plurality of first passages (24) for transporting a first fluid (25) and a plurality of second passages (26) for transporting a second fluid (27). The first and second passages are arranged in stacked, alternating relationship, are separated from one another by relatively thin plates (30) and (32), and surround a central axis (22). The thickness of the first and second passages are selected so that the first and second fluids, respectively, are transported with laminar flow through the passages. To enhance thermal energy transfer between first and second passages, the latter are arranged so each first passage is in thermal communication with an associated second passage along substantially its entire length, and vice versa with respect to the second passages. The heat exchangers may be stacked to achieve a modular heat exchange assembly (300). Certain heat exchangers in the assembly may be designed slightly differently than other heat exchangers to address changes in fluid properties during transport through the heat exchanger, so as to enhance overall thermal effectiveness of the assembly.

  3. Active combustion flow modulation valve

    DOE Patents [OSTI]

    Hensel, John Peter; Black, Nathaniel; Thorton, Jimmy Dean; Vipperman, Jeffrey Stuart; Lambeth, David N; Clark, William W

    2013-09-24T23:59:59.000Z

    A flow modulation valve has a slidably translating hollow armature with at least one energizable coil wound around and fixably attached to the hollow armature. The energizable coil or coils are influenced by at least one permanent magnet surrounding the hollow armature and supported by an outer casing. Lorentz forces on the energizable coils which are translated to the hollow armature, increase or decrease the flow area to provide flow throttling action. The extent of hollow armature translation depends on the value of current supplied and the direction of translation depends on the direction of current flow. The compact nature of the flow modulation valve combined with the high forces afforded by the actuator design provide a flow modulation valve which is highly responsive to high-rate input control signals.

  4. The propagation of kinetic energy across scales in turbulent flows

    E-Print Network [OSTI]

    Cardesa, José I; Dong, Siwei; Jiménez, Javier

    2015-01-01T23:59:59.000Z

    A temporal study of energy transfer across length scales is performed in 3D numerical simulations of homogeneous shear flow and isotropic turbulence, at Reynolds numbers in the range $Re_{\\lambda}=107-384$. The average time taken by perturbations in the energy flux to travel between scales is measured and shown to be additive, as inferred from the agreement between the total travel time from a given scale to the smallest dissipative motions, and the time estimated from successive jumps through intermediate scales. Our data suggests that the propagation of disturbances in the energy flux is independent of the forcing and that it defines a `velocity' that determines the energy flux itself. These results support that the cascade is, on average, a scale-local process where energy is continuously transmitted from one scale to the next in order of decreasing size.

  5. INTERACTIONS OF FLOWING PLASMA WITH COLLECTING SPHERE/OBJECTS

    SciTech Connect (OSTI)

    HUTCHINSON, IAN H.

    2013-10-31T23:59:59.000Z

    The proposer’s computational flowing plasma group, supported in part by NSF/DOE since 2006, has been enormously productive. It has published 22 journal articles, of which 3 are in Physical Review Letters; received a total of 330 citations, and made 5 invited and numerous contributed presentations at international conferences. In addition, other groups have published at least 3 papers [20-22] based upon results they have obtained from the SCEPTIC code, developed by the proposer. The codes developed for this subject are Particle In Cell (PIC) codes, representing the entire ion distribution function and its variation in space in the vicinity of an absorbing object.

  6. Numerical simulation of water flow around a rigid fishing net

    E-Print Network [OSTI]

    Roger Lewandowski; Géraldine Pichot

    2006-12-20T23:59:59.000Z

    This paper is devoted to the simulation of the flow around and inside a rigid axisymmetric net. We describe first how experimental data have been obtained. We show in detail the modelization. The model is based on a Reynolds Averaged Navier-Stokes turbulence model penalized by a term based on the Brinkman law. At the out-boundary of the computational box, we have used a "ghost" boundary condition. We show that the corresponding variational problem has a solution. Then the numerical scheme is given and the paper finishes with numerical simulations compared with the experimental data.

  7. Data-flow algorithms for parallel matrix computations

    SciTech Connect (OSTI)

    O'Leary, D.P.; Stewart, G.W.

    1985-08-01T23:59:59.000Z

    This document develops some algorithms and tools for solving matrix problems on parallel-processing computers. Operations are synchronized through data-flow alone, which makes global synchronization unnecessary and enables the algorithms to be implemented on machines with very simple operating systems and communication protocols. As examples, the authors present algorithms that form the main modules for solving Liapounov matrix equations. They compare this approach to wave-front array processors and systolic arrays, and note its advantages in handling mis-sized problems, in evaluating variations of algorithms or architectures, in moving algorithms from system to system, and in debugging parallel algorithms on sequential machines.

  8. Subsurface Flow and Transport | EMSL

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

    subsurface related to contaminant transport, carbon cycling, enhanced oil recovery and carbon dioxide sequestration. See a complete list of Subsurface Flow and Transport...

  9. Resource variation and the evolution of phenotypic plasticity in fishes

    E-Print Network [OSTI]

    Ruehl, Clifton Benjamin

    2004-09-30T23:59:59.000Z

    variation. The first empirical study addresses trophic plasticity, population divergence, and the effect of fine-scale environmental variation in western mosquitofish (Gambusia affinis). Offspring from two populations were fed either attached or unattached...

  10. The dynamics of genetic and morphological variation on volcanic islands

    E-Print Network [OSTI]

    Thorpe, Roger Stephen

    : volcanism; phylogeography; geographical variation; natural selection; Canary islands; Tarentola 1 and Canary islands). It has been argued that population extinctions, recolonizations and associ- ated a role in shaping geographical variation. The islands of the Canary Archipelago provide an excellent

  11. Statistical static timing analysis considering process variations and crosstalk 

    E-Print Network [OSTI]

    Veluswami, Senthilkumar

    2005-11-01T23:59:59.000Z

    Increasing relative semiconductor process variations are making the prediction of realistic worst-case integrated circuit delay or sign-off yield more difficult. As process geometries shrink, intra-die variations have ...

  12. Variations in the manufacturing of Rockwell test blocks

    E-Print Network [OSTI]

    Vora, Jairaj Deepak

    2009-01-01T23:59:59.000Z

    This research analyzes the variations occurring in the manufacturing of Rockwell hardness test blocks. Test blocks of different materials and hardness were analyzed and the variations were identified using the Ishikawa ...

  13. Interactive Exploration of Multigranularity Spatial and Temporal Datacubes: Providing ComputerAssisted Geovisualization Support

    E-Print Network [OSTI]

    Interactive Exploration of Multigranularity Spatial and Temporal Datacubes: Providing Computer://sirs.scg.ulaval.ca/yvanbedard This paper addresses issues of geovisualization regarding the process of interactive multi granularity spatial and temporal knowledge discovery for decisionmaking. In such an interactive context

  14. Reduction of Ground-Based Sensor Sites for Spatio-Temporal Analysis of Aerosols

    E-Print Network [OSTI]

    Vucetic, Slobodan

    Reduction of Ground-Based Sensor Sites for Spatio- Temporal Analysis of Aerosols Vladan in this study is estimation of an important property of atmosphere, called Aerosol Optical Depth (AOD). Remote of spatio- temporal aerosol patterns on a global scale. Ground-based AOD estimation is more accurate

  15. Reconstruction of Missing Data in Social Networks Based on Temporal Patterns of Interactions

    E-Print Network [OSTI]

    Bertozzi, Andrea L.

    Reconstruction of Missing Data in Social Networks Based on Temporal Patterns of Interactions Alexey events in the future. Such event #12;Reconstruction of Missing Data Based on Temporal Patterns 2 the missing data about the participants based on the behavioral model. t t t Figure 2. Graphical

  16. Reconstruction of Missing Data in Social Networks Based on Temporal Patterns of Interactions

    E-Print Network [OSTI]

    Soatto, Stefano

    Reconstruction of Missing Data in Social Networks Based on Temporal Patterns of Interactions Alexey events in the future. Such event #12;Reconstruction of Missing Data Based on Temporal Patterns 2 Angeles E-mail: alexey@math.ucla.edu, mbshort@math.ucla.edu, bertozzi@math.ucla.edu Abstract. We discuss

  17. activated glomeruli, (ii) the spatial combination of active neurons, (iii) the slow temporal sequence of activity

    E-Print Network [OSTI]

    system is not a static phenomenon but a dynamical process with different temporal components, eachof them probably readout byan adapted mechanism. This spatio-temporal representation is moreover dyna- mically be selected on the basis of their respiratory phase. Such a functional phase-coding relative to theta cycle (i

  18. Mining Probabilistic Frequent Spatio-Temporal Sequential Patterns with Gap Constraints from Uncertain Databases

    E-Print Network [OSTI]

    Pei, Jian

    discovery in ecology [11]. The main computational challenge in mining spatio- temporal sequential patternsMining Probabilistic Frequent Spatio-Temporal Sequential Patterns with Gap Constraints from in much interest in itemset mining for uncertain transaction databases. In this paper, we focus on pattern

  19. Behavioural Processes 71 (2006) 2940 Effects of temporal clumping and payoff accumulation

    E-Print Network [OSTI]

    Stevens, Jeffrey

    2006-01-01T23:59:59.000Z

    Behavioural Processes 71 (2006) 29­40 Effects of temporal clumping and payoff accumulation accumulation and temporal clumping on impulsiveness and cooperation. Payoff accumulation refers to a situation where the benefits gained from each choice trial accumulate from one trial to the next, and only become

  20. AN ITERATIVE SPATIO-TEMPORAL SPEECH ENHANCEMENT ALGORITHM FOR MICROPHONE ARRAYS

    E-Print Network [OSTI]

    Douglas, Scott C.

    AN ITERATIVE SPATIO-TEMPORAL SPEECH ENHANCEMENT ALGORITHM FOR MICROPHONE ARRAYS !"#"$ %&'t" "nd +c ABSTRACT We present a new spatio-temporal algorithm for speech enhancement using microphone arrays. Our-dependent parameter settings. Index Terms4 Speech enhancement, acoustic arrays, adaptive arrays, eigenvalues

  1. Temporal Data Mining Approaches for Sustainable Chiller Management in Data Centers

    E-Print Network [OSTI]

    A Temporal Data Mining Approaches for Sustainable Chiller Management in Data Centers DEBPRAKASH the design and im- plementation of CAMAS (Chiller Advisory and MAnagement System), a temporal data mining solution to mine and manage chiller installations. CAMAS embodies a set of algorithms for processing

  2. Temporal Data Mining Approaches for Sustainable Chiller Management in Data Centers

    E-Print Network [OSTI]

    Ramakrishnan, Naren

    34 Temporal Data Mining Approaches for Sustainable Chiller Management in Data Centers DEBPRAKASH the design and implementation of CAMAS (Chiller Advisory and MAnagement System), a temporal data mining solution to mine and manage chiller installations. CAMAS embodies a set of algorithms for processing

  3. Estimating mutation parameters, population history and genealogy simultaneously from temporally spaced

    E-Print Network [OSTI]

    Nicholls, Geoff

    Estimating mutation parameters, population history and genealogy simultaneously from temporally and population size that incorporates the uncertainty in the genealogy of such temporally spaced sequences features of this approach on a genealogy of HIV-1 envelope (env) partial sequences. #12;1 Introduction One

  4. Luminance mechanisms mediate the motion of redgreen isoluminant gratings: the role of ``temporal chromatic aberration''

    E-Print Network [OSTI]

    Mullen, Kathy T.

    Luminance mechanisms mediate the motion of red­green isoluminant gratings: the role of ``temporal of variable luminance or chromatic noise. In the first experiment, we used dynamic luminance noise to show that direction thresholds for red­green grating motion are masked by luminance noise over the entire temporal

  5. Spatio-temporal availability of soft mast in clearcuts in the Southern Appalachians

    E-Print Network [OSTI]

    Mitchell, Mike

    Spatio-temporal availability of soft mast in clearcuts in the Southern Appalachians Melissa J availability of soft mast though time is not fully understood. We tested a theoretical model of temporal availability of soft mast in clearcuts using empirical data on percent cover and berry production

  6. Temporal Dependency based Checkpoint Selection for Dynamic Verification of Fixed-time Constraints

    E-Print Network [OSTI]

    Yang, Yun

    Swinburne University of Technology PO Box 218, Hawthorn, Melbourne, Australia 3122 +61 - 3 - 9214 8739 of such constraints is consequently unnecessary and can severely impact the efficiency of overall temporal simulation further demonstrate that our new strategy can improve the efficiency of overall temporal

  7. Nordic Journal of Computing 9(2002), 145188. TEMPORAL CONCURRENT CONSTRAINT

    E-Print Network [OSTI]

    Valencia, Frank D.

    2002-01-01T23:59:59.000Z

    Nordic Journal of Computing 9(2002), 145­188. TEMPORAL CONCURRENT CONSTRAINT PROGRAMMING on this semantics, we develop a proof system for linear-temporal properties of these processes. The expressiveness of ntcc is illustrated by modeling cells, timed systems such as RCX controllers, multi-agent systems

  8. IDENTIFYING TEMPORAL TRENDS IN TREATED SAGEBRUSH COMMUNITIES USING REMOTELY SENSED IMAGERY

    E-Print Network [OSTI]

    Ramsey, R. Douglas

    IDENTIFYING TEMPORAL TRENDS IN TREATED SAGEBRUSH COMMUNITIES USING REMOTELY SENSED IMAGERY by Eric Identifying Temporal Trends in Treated Sagebrush Communities Using Remotely Sensed Imagery by Eric D. Sant over time, brightness and greenness provided diagnostic trends and condition of treated big sagebrush

  9. Saving for the future self: Neural measures of future self-continuity predict temporal discounting

    E-Print Network [OSTI]

    Knutson, Brian

    Saving for the future self: Neural measures of future self-continuity predict temporal discounting not increased their rate of saving. In a phenomenon known as `temporal discounting', people value immediate and treat the future self differently from the present self, and so might fail to save for their future

  10. Hierarchical Representation of Videos with Spatio-Temporal Fibers Ratnesh Kumar Guillaume Charpiat Monique Thonnat

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Hierarchical Representation of Videos with Spatio-Temporal Fibers Ratnesh Kumar Guillaume Charpiat representation of videos, as spatio- temporal fibers. These fibers are clusters of trajectories that are meshed spatially in the image domain. They form a hier- archical partition of the video into regions

  11. VIDEO SUMMARIZATION BY SPATIAL-TEMPORAL GRAPH OPTIMIZATION Shi Lu, Michael R. Lyu, Irwin King

    E-Print Network [OSTI]

    King, Kuo Chin Irwin

    VIDEO SUMMARIZATION BY SPATIAL-TEMPORAL GRAPH OPTIMIZATION Shi Lu, Michael R. Lyu, Irwin King SAR {slu, lyu, king}@cse.cuhk.edu.hk ABSTRACT In this paper we present a novel approach for video sum-temporal content cov- erage and visual coherence of the video summary. The ap- proach has three stages. First

  12. Aerosol acidity in rural New England: Temporal trends and source region analysis

    E-Print Network [OSTI]

    Fischer, Emily V.

    the dissociation of sulfuric acid (H2SO4) that condenses after forming via the gas phase oxidation of sulfurAerosol acidity in rural New England: Temporal trends and source region analysis L. D. Ziemba,1,2 E. Talbot (2007), Aerosol acidity in rural New England: Temporal trends and source region analysis, J

  13. Process Mining and Verification of Properties: An Approach based on Temporal Logic

    E-Print Network [OSTI]

    van der Aalst, Wil

    , temporal logic, business process management, workflow management, data mining, Petri nets. 1 IntroductionProcess Mining and Verification of Properties: An Approach based on Temporal Logic W.M.P. van der flexible, both the need for, and the complexity of monitoring increases. Our earlier work on process mining

  14. Consistent parametric estimation of the intensity of a spatial-temporal point process.

    E-Print Network [OSTI]

    Schoenberg, Frederic Paik (Rick)

    Consistent parametric estimation of the intensity of a spatial-temporal point process. Frederic under which parametric estimates of the intensity of a spatial-temporal point process are consistent. Although the actual point process being estimated may not be Poisson, an estimate involving maximizing

  15. A Probabilistic Temporal Logic with Frequency Operators and Its Model Checking

    E-Print Network [OSTI]

    Tomita, Takashi; Yonezaki, Naoki; 10.4204/EPTCS.73.9

    2011-01-01T23:59:59.000Z

    Probabilistic Computation Tree Logic (PCTL) and Continuous Stochastic Logic (CSL) are often used to describe specifications of probabilistic properties for discrete time and continuous time, respectively. In PCTL and CSL, the possibility of executions satisfying some temporal properties can be quantitatively represented by the probabilistic extension of the path quantifiers in their basic Computation Tree Logic (CTL), however, path formulae of them are expressed via the same operators in CTL. For this reason, both of them cannot represent formulae with quantitative temporal properties, such as those of the form "some properties hold to more than 80% of time points (in a certain bounded interval) on the path." In this paper, we introduce a new temporal operator which expressed the notion of frequency of events, and define probabilistic frequency temporal logic (PFTL) based on CTL\\star. As a result, we can easily represent the temporal properties of behavior in probabilistic systems. However, it is difficult to...

  16. Rényi entropy flows from quantum heat engines

    E-Print Network [OSTI]

    Mohammad H. Ansari; Yuli V. Nazarov

    2015-03-20T23:59:59.000Z

    We evaluate Renyi entropy flows from generic quantum heat engines (QHE) to a weakly-coupled probe environment kept in thermal equilibrium. We show that the flows are determined not only by heat flow but also by a quantum coherent flow that can be separately measured in experiment apart from the heat flow measurement. The same pertains to Shanon entropy flow. This appeals for a revision of the concept of entropy flows in quantum nonequlibrium thermodynamics.

  17. Spatio-temporal spectral analysis of a forced cylinder wake

    E-Print Network [OSTI]

    D'Adamo, Juan; Wesfreid, José Eduardo

    2011-01-01T23:59:59.000Z

    The wake of a circular cylinder performing rotary oscillations is studied using hydrodynamic tunnel experiments at $Re=100$. Two-dimensional particle image velocimetry on the mid-plane perpendicular to the axis of cylinder is used to characterize the spatial development of the flow and its stability properties. The lock-in phenomenon that determines the boundaries between regions of the forcing parameter space were the wake is globally unstable or convectively unstable is scrutinized using the experimental data. A novel method based on the analysis of power density spectra of the flow allows us to give a detailed description of the forced wake, shedding light on the energy distribution in the different frequency components and in particular on a cascade-like mechanism evidenced for a high amplitude of the forcing oscillation. In addition, a calculation of the drag from the velocity field is performed, allowing us to relate the resulting force on the body to the wake properties.

  18. ANTI-PARALLEL EUV FLOWS OBSERVED ALONG ACTIVE REGION FILAMENT THREADS WITH HI-C

    SciTech Connect (OSTI)

    Alexander, Caroline E.; Walsh, Robert W.; Régnier, Stéphane [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom)] [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Cirtain, Jonathan; Winebarger, Amy R. [NASA Marshall Space Flight Center, VP 62, Huntsville, AL 35812 (United States)] [NASA Marshall Space Flight Center, VP 62, Huntsville, AL 35812 (United States); Golub, Leon; Korreck, Kelly; Weber, Mark [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)] [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Kobayashi, Ken [Center for Space Plasma and Aeronomic Research, The University of Alabama in Huntsville, 320 Sparkman Drive, Huntsville, AL 35805 (United States)] [Center for Space Plasma and Aeronomic Research, The University of Alabama in Huntsville, 320 Sparkman Drive, Huntsville, AL 35805 (United States); Platt, Simon; Mitchell, Nick [School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Preston PR1 2HE (United Kingdom)] [School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Preston PR1 2HE (United Kingdom); DePontieu, Bart; Title, Alan [Lockheed Martin Solar and Astrophysics Lab, 3251 Hanover Street, Org. ADBS, Bldg. 252, Palo Alto, CA (United States)] [Lockheed Martin Solar and Astrophysics Lab, 3251 Hanover Street, Org. ADBS, Bldg. 252, Palo Alto, CA (United States); DeForest, Craig [Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States)] [Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States); Kuzin, Sergey [P.N. Lebedev Physical institute of the Russian Academy of Sciences, Leninskii prospekt, 53, 119991 Moscow (Russian Federation)] [P.N. Lebedev Physical institute of the Russian Academy of Sciences, Leninskii prospekt, 53, 119991 Moscow (Russian Federation)

    2013-09-20T23:59:59.000Z

    Plasma flows within prominences/filaments have been observed for many years and hold valuable clues concerning the mass and energy balance within these structures. Previous observations of these flows primarily come from H? and cool extreme-ultraviolet (EUV) lines (e.g., 304 Å) where estimates of the size of the prominence threads has been limited by the resolution of the available instrumentation. Evidence of 'counter-steaming' flows has previously been inferred from these cool plasma observations, but now, for the first time, these flows have been directly imaged along fundamental filament threads within the million degree corona (at 193 Å). In this work, we present observations of an AR filament observed with the High-resolution Coronal Imager (Hi-C) that exhibits anti-parallel flows along adjacent filament threads. Complementary data from the Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager are presented. The ultra-high spatial and temporal resolution of Hi-C allow the anti-parallel flow velocities to be measured (70-80 km s{sup –1}) and gives an indication of the resolvable thickness of the individual strands (0.''8 ± 0.''1). The temperature of the plasma flows was estimated to be log T (K) = 5.45 ± 0.10 using Emission Measure loci analysis. We find that SDO/AIA cannot clearly observe these anti-parallel flows or measure their velocity or thread width due to its larger pixel size. We suggest that anti-parallel/counter-streaming flows are likely commonplace within all filaments and are currently not observed in EUV due to current instrument spatial resolution.

  19. Bypass Flow Computations using a One-Twelfth Symmetric Sector For Normal Operation in a 350 MWth VHTR

    SciTech Connect (OSTI)

    Richard W. Johnson; Hiroyuki Sato

    2010-10-01T23:59:59.000Z

    Significant uncertainty exists about the effects of bypass flow in a prismatic gas-cooled very high temperature reactor (VHTR). Bypass flow is the flow in the gaps between prismatic graphite blocks in the core. The gaps are present because of variations in their construction, imperfect installation and expansion and shrinkage from thermal heating and neutron fluence. Calculations are performed using computational fluid dynamics (CFD) for flow of the helium coolant in the gap and coolant channels along with conjugate heat generation and heat transfer in the fuel compacts and graphite. A commercial CFD code is used for all of the computations. A one-twelfth sector of a standard hexagonal block column is used for the CFD model because of its symmetry. Various scenarios are computed by varying the gap width from zero to 5 mm, varying the total heat generation rate to examine average and peak radial generation rates and variation of the graphite block geometry to account for the effects of shrinkage caused by irradiation. The calculations are for a 350 MWth prismatic reactor. It is shown that the effect of increasing gap width, while maintaining the same total mass flow rate, causes increased maximum fuel temperature while providing significant cooling to the near-gap region. The maximum outlet coolant temperature variation is increased by the presence of gap flow and also by an increase in total heat generation with a gap present. The effect of block shrinkage is actually to decrease maximum fuel temperature compared to a similar reference case.

  20. Mechanism governing separation in microfluidic pinched flow fractionation devices

    E-Print Network [OSTI]

    Sumedh R. Risbud; German Drazer

    2014-04-04T23:59:59.000Z

    We present a computational investigation of the mechanism governing size-based particle separation in microfluidic pinched flow fractionation. We study the behavior of particles moving through a pinching gap (i.e., a constriction in the aperture of a channel) in the Stokes regime as a function of particle size. The constriction aperture is created by a plane wall and spherical obstacle, and emulates the pinching segment in pinched flow fractionation devices. The simulation results show that the distance of closest approach between the particle and obstacle surfaces (along a trajectory) decreases with increasing particle size. We then use the distance of closest approach to investigate the effect of short-range repulsive non-hydrodynamic interactions (e.g., solid-solid contact). We define a critical trajectory as the one in which the minimum particle-obstacle separation is equal to the range of the non-hydrodynamic interactions. The results further show that the initial offset of the critical trajectory (defined as the critical offset) increases with particle size. We interpret the variation of the critical offset with particle size as the basis for size-based microfluidic separation in pinched flow fractionation. We also compare the effect of different driving fields on the particle trajectories; we simulate a constant force driving the particles in a quiescent fluid as well as a freely suspended particles in a pressure-driven flow. We observe that the particles driven by a constant force approach closer to the obstacle than those suspended in a flow (for the same initial offset). On the other hand, the increment in the critical offset (as a function of particle size) is larger in the pressure-driven case than in the force-driven case. Thus, pressure-driven particle separation using pinched flow fractionation would prove more effective than its force-driven counterpart.

  1. Flow calculations for Yucca Mountain groundwater travel time (GWTT-95)

    SciTech Connect (OSTI)

    Altman, S.J.; Arnold, B.W.; Barnard, R.W.; Barr, G.E.; Ho, C.K.; McKenna, S.A.; Eaton, R.R.

    1996-09-01T23:59:59.000Z

    In 1983, high-level radioactive waste repository performance requirements related to groundwater travel time were defined by NRC subsystem regulation 10 CFR 60.113. Although DOE is not presently attempting to demonstrate compliance with that regulation, understanding of the prevalence of fast paths in the groundwater flow system remains a critical element of any safety analyses for a potential repository system at Yucca Mountain, Nevada. Therefore, this analysis was performed to allow comparison of fast-path flow against the criteria set forth in the regulation. Models developed to describe the conditions for initiation, propagation, and sustainability of rapid groundwater movement in both the unsaturated and saturated zones will form part of the technical basis for total- system analyses to assess site viability and site licensability. One of the most significant findings is that the fastest travel times in both unsaturated and saturated zones are in the southern portion of the potential repository, so it is recommended that site characterization studies concentrate on this area. Results support the assumptions regarding the importance of an appropriate conceptual model of groundwater flow and the incorporation of heterogeneous material properties into the analyses. Groundwater travel times are sensitive to variation/uncertainty in hydrologic parameters and in infiltration flux at upper boundary of the problem domain. Simulated travel times are also sensitive to poorly constrained parameters of the interaction between flow in fractures and in the matrix.

  2. Seismic attenuation due to wave-induced flow

    SciTech Connect (OSTI)

    Pride, S.R.; Berryman, J.G.; Harris, J.M.

    2003-10-09T23:59:59.000Z

    Analytical expressions for three P-wave attenuation mechanisms in sedimentary rocks are given a unified theoretical framework. Two of the models concern wave-induced flow due to heterogeneity in the elastic moduli at mesoscopic scales (scales greater than grain sizes but smaller than wavelengths). In the first model, the heterogeneity is due to lithological variations (e.g., mixtures of sands and clays) with a single fluid saturating all the pores. In the second model, a single uniform lithology is saturated in mesoscopic ''patches'' by two immiscible fluids (e.g., air and water). In the third model, the heterogeneity is at ''microscopic'' grain scales (broken grain contacts and/or micro-cracks in the grains) and the associated fluid response corresponds to ''squirt flow''. The model of squirt flow derived here reduces to proper limits as any of the fluid bulk modulus, crack porosity, and/or frequency is reduced to zero. It is shown that squirt flow is incapable of explaining the measured level of loss (10{sup -2} < Q{sup -1} < 10{sup -1}) within the seismic band of frequencies (1 to 10{sup 4} Hz); however, either of the two mesoscopic scale models easily produce enough attenuation to explain the field data.

  3. Variational thermodynamics of relativistic thin disks

    E-Print Network [OSTI]

    A C Gutiérrez-Piñeres; C S Lopez-Monsalvo; H Quevedo

    2014-08-18T23:59:59.000Z

    We present a relativistic model describing a thin disk system composed of two fluids. The system is surrounded by a halo in the presence of a non-trivial electromagnetic field. We show that the model is compatible with the variational multi-fluid thermodynamics formalism, allowing us to determine all the thermodynamic variables associated with the matter content of the disk. The asymptotic behaviour of these quantities indicates that the single fluid interpretation should be abandoned in favour of a two-fluid model.

  4. Variations on a Theme Issue 8

    E-Print Network [OSTI]

    Piacentini, Valerie; Clark, Sheila

    1984-01-01T23:59:59.000Z

    - Warped Out Publications Distracting - Shan a (Don't you get tired of playing with paper?) Var-iations on a Theme 8, in which Kirk and Spack find their leave less r-estful than they e"pect, is put aut by ScoTpress and is available from Sheila Clark 6... universe. (Anyone wanting to read the story from which we took our 'inspiration', it is 'Spack's Pilgrimage' in Kraith Collected IV; contact Margaret Draper, The Lodge, Wantage Road, Rowstock, Didcot, DXON, who acts as U.K. agent far it, or Debbie...

  5. VARIATIONS IN THE SOLAR NEUTRINO FZUX

    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 Maps to Predict4 VARIATIONS IN THE SOLAR NEUTRINO

  6. Network Flow Optimization under Uncertainty

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    Network model in words Minimize the cost of satisfying demands for electric energy By: imports, exports and electricity Subject to: conservation of energy flows (net after losses), lower and upper bounds on flows is a reactive approach: how would the optimal solution have changed if I'd only known? · Proactive approaches

  7. Redox Flow Batteries, a Review

    SciTech Connect (OSTI)

    U. Tennessee Knoxville; U. Texas Austin; McGill U; Weber, Adam Z.; Mench, Matthew M.; Meyers, Jeremy P.; Ross, Philip N.; Gostick, Jeffrey T.; Liu, Qinghua

    2011-07-15T23:59:59.000Z

    Redox flow batteries are enjoying a renaissance due to their ability to store large amounts of electrical energy relatively cheaply and efficiently. In this review, we examine the components of redox flow batteries with a focus on understanding the underlying physical processes. The various transport and kinetic phenomena are discussed along with the most common redox couples.

  8. Temporal and spectral imaging with micro-CT

    SciTech Connect (OSTI)

    Johnston, Samuel M.; Johnson, G. Allan; Badea, Cristian T. [Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina 27710 (United States)

    2012-08-15T23:59:59.000Z

    Purpose: Micro-CT is widely used for small animal imaging in preclinical studies of cardiopulmonary disease, but further development is needed to improve spatial resolution, temporal resolution, and material contrast. We present a technique for visualizing the changing distribution of iodine in the cardiac cycle with dual source micro-CT. Methods: The approach entails a retrospectively gated dual energy scan with optimized filters and voltages, and a series of computational operations to reconstruct the data. Projection interpolation and five-dimensional bilateral filtration (three spatial dimensions + time + energy) are used to reduce noise and artifacts associated with retrospective gating. We reconstruct separate volumes corresponding to different cardiac phases and apply a linear transformation to decompose these volumes into components representing concentrations of water and iodine. Since the resulting material images are still compromised by noise, we improve their quality in an iterative process that minimizes the discrepancy between the original acquired projections and the projections predicted by the reconstructed volumes. The values in the voxels of each of the reconstructed volumes represent the coefficients of linear combinations of basis functions over time and energy. We have implemented the reconstruction algorithm on a graphics processing unit (GPU) with CUDA. We tested the utility of the technique in simulations and applied the technique in an in vivo scan of a C57BL/6 mouse injected with blood pool contrast agent at a dose of 0.01 ml/g body weight. Postreconstruction, at each cardiac phase in the iodine images, we segmented the left ventricle and computed its volume. Using the maximum and minimum volumes in the left ventricle, we calculated the stroke volume, the ejection fraction, and the cardiac output. Results: Our proposed method produces five-dimensional volumetric images that distinguish different materials at different points in time, and can be used to segment regions containing iodinated blood and compute measures of cardiac function. Conclusions: We believe this combined spectral and temporal imaging technique will be useful for future studies of cardiopulmonary disease in small animals.

  9. Wavy flow cooling concept for turbine airfoils

    DOE Patents [OSTI]

    Liang, George (Palm City, FL)

    2010-08-31T23:59:59.000Z

    An airfoil including an outer wall and a cooling cavity formed therein. The cooling cavity includes a leading edge flow channel located adjacent a leading edge of the airfoil and a trailing edge flow channel located adjacent a trailing edge of the airfoil. Each of the leading edge and trailing edge flow channels define respective first and second flow axes located between pressure and suction sides of the airfoil. A plurality of rib members are located within each of the flow channels, spaced along the flow axes, and alternately extending from opposing sides of the flow channels to define undulating flow paths through the flow channels.

  10. Small to large-scale diagenetic variation in Norphlet sandstone, onshore and offshore Mississippi, Alabama, and Florida

    SciTech Connect (OSTI)

    Kugler, R.L.

    1989-03-01T23:59:59.000Z

    The detrital composition of Norphlet sandstone is relatively uniform on a regional scale, consisting of quartz, potassium feldspar, albite, and rock fragments comprised of these minerals. However, the diagenetic character of the sandstones is variable on a scale ranging from the individual laminations to single hydrocarbon-producing fields to regions encompassing several fields or offshore blocks. Small-scale variation results primarily from textural differences related to depositional processes in eolian and shallow marine systems. Degree of feldspar alteration and types of authigenic clay and carbonate minerals vary on a regional scale. Illite, dolomite, ferroan dolomite, and ferroan magnesite (breunnerite) are common in onshore wells in Alabama, whereas magnesium-rich chlorite and calcite are present in offshore Alabama and Florida. However, diagenetic character is more variable on a fieldwide scale than previously recognized. In Hatter's Pond field, Mobile County, Alabama, breunnerite, which has not been described previously in these sandstones, is the dominant cement in some wells but is absent others. Although illite is the most common authigenic clay throughout the field, chlorite is the most abundant clay in some wells. Because of uniformity of detrital composition, diagenetic variations cannot be related to differences in provenance, particularly on the scale of a single field. Factors that must account for variations in diagenesis include (1) differences in burial history relative to thermal sulfate reduction; (2) variation in fluid flow relative to subbasins, structural highs, fault systems, depositional texture, and early diagenetic character of the sandstones; and (3) variation in composition of underlying Louann evaporites.

  11. Vertical flow chemical detection portal

    DOE Patents [OSTI]

    Linker, K.L.; Hannum, D.W.; Conrad, F.J.

    1999-06-22T23:59:59.000Z

    A portal apparatus is described for screening objects or persons for the presence of trace amounts of chemical substances such as illicit drugs or explosives. The apparatus has a test space, in which a person may stand, defined by two generally upright sides spanned by a horizontal transom. One or more fans in the transom generate a downward air flow (uni-directional) within the test space. The air flows downwardly from a high pressure upper zone, past the object or person to be screened. Air moving past the object dislodges from the surface thereof both volatile and nonvolatile particles of the target substance. The particles are entrained into the air flow which continues flowing downward to a lower zone of reduced pressure, where the particle-bearing air stream is directed out of the test space and toward preconcentrator and detection components. The sides of the portal are specially configured to partially contain and maintain the air flow. 3 figs.

  12. Sound temporal envelope and time-patterns of activity in the human auditory pathway : an fMRI study

    E-Print Network [OSTI]

    Harms, Michael Patrick, 1972-

    2002-01-01T23:59:59.000Z

    The temporal envelope of sound strongly influences the intelligibility of speech, pattern analysis, and the grouping of sequential stimuli. This thesis examined the coding of sound temporal envelope in the time-patterns ...

  13. Recurrent flow analysis in spatiotemporally chaotic 2-dimensional Kolmogorov flow

    E-Print Network [OSTI]

    Dan Lucas; Rich Kerswell

    2015-04-01T23:59:59.000Z

    Motivated by recent success in the dynamical systems approach to transitional flow, we study the efficiency and effectiveness of extracting simple invariant sets (recurrent flows) directly from chaotic/turbulent flows and the potential of these sets for providing predictions of certain statistics of the flow. Two-dimensional Kolmogorov flow (the 2D Navier-Stokes equations with a sinusoidal body force) is studied both over a square [0, 2{\\pi}]2 torus and a rectangular torus extended in the forcing direction. In the former case, an order of magnitude more recurrent flows are found than previously (Chandler & Kerswell 2013) and shown to give improved predictions for the dissipation and energy pdfs of the chaos via periodic orbit theory. Over the extended torus at low forcing amplitudes, some extracted states mimick the statistics of the spatially-localised chaos present surprisingly well recalling the striking finding of Kawahara & Kida (2001) in low-Reynolds-number plane Couette flow. At higher forcing amplitudes, however, success is limited highlighting the increased dimensionality of the chaos and the need for larger data sets. Algorithmic developments to improve the extraction procedure are discussed.

  14. Comparison of Nozzle and Flow Straighteners for Tank Waste Sluicing Applications Letter Report

    SciTech Connect (OSTI)

    Mullen, O Dennis; Jackson, David R.

    2000-09-29T23:59:59.000Z

    Nozzles and flow straighteners were compared to assess the relative quality of the water streams for sluicing waste from underground storage tankes. The criteria for comparison were 1) the impact force produced by the streams over a range of distance from the nozzle impinging on target plates, and 2) the coherence of the streams as manifest by the variation of force on targets of two different sizes. It was determined that 1) the standard Hanford flow straightener is measurable less effective than a commercial firefighting flow straightener at producing a coherent stream when used with the standard Hanford nozzle, and 2) a lighter and more compact firefighting deluge nozzle will deliver a stream of equal quality to that from the Hanford nozzle when either nozzle is used with the commercial flow straightener.

  15. Variation in DNA content of blood cells of largemouth bass from contaminated and uncontaminated waters

    SciTech Connect (OSTI)

    Lingenfelser, S.F. [Fish and Wildlife Service, White Marsh, VA (United States); Dallas, C.E. [Univ. of Georgia, Athens, GA (United States). Dept. of Pharmacology and Toxicology; Jagoe, C.H.; Smith, M.H.; Brisbin, I.L. Jr.; Chesser, R.K. [Savannah River Ecology Lab., Aiken, SC (United States)

    1997-10-01T23:59:59.000Z

    Largemouth bass (Micropterus salmoides) were collected from locations with and without documented histories of pollution in Georgia and South Carolina. Whole blood samples were collected from over 3,000 bass and analyzed by flow cytometry to measure changes in cellular DNA content and cell cycle distribution. The coefficient of variation (CV) of the cell cycle phase G{sub 0}G{sub 1} peak was used as a measure of variation in DNA content within an individual. The mean CV varied significantly among locations, and some locations with known chemical or radioactive contaminants had higher CVs. Plotting the frequency distribution of CV values for each site revealed greater skewness and kurtosis in most locations with known contaminants. In each case, a right skewness indicated higher proportions of bass with unusually high CV in these locations. Aneuploid-like patterns were detected in the DNA histograms of five fish, all from locations with histories of contamination. The percentage of cells distributed among phases of the cell cycle (G{sub 0}/G{sub 1}, S, and G{sub 2}M) varied significantly among locations, but there was no apparent relationship to contaminant distribution. Differences in CV and frequency of aneuploids among sites with and without histories of pollution were generally small, but increased variation in DNA content may be associated with contaminant exposure at some locations.

  16. Drainage capture and discharge variations driven by glaciation in the Southern Alps, New Zealand

    SciTech Connect (OSTI)

    Ann V. Rowan; Mitchell A. Plummer; Simon H. Brocklehurst; Merren A. Jones; David M. Schultz

    2013-02-01T23:59:59.000Z

    Sediment flux in proglacial fluvial settings is primarily controlled by discharge, which usually varies predictably over a glacial–interglacial cycle. However, glaciers can flow against the topographic gradient to cross drainage divides, reshaping fluvial drainage networks and dramatically altering discharge. In turn, these variations in discharge will be recorded by proglacial stratigraphy. Glacial-drainage capture often occurs in alpine environments where ice caps straddle range divides, and more subtly where shallow drainage divides cross valley floors. We investigate discharge variations resulting from glacial-drainage capture over the past 40 k.y. for the adjacent Ashburton, Rangitata, and Rakaia basins in the Southern Alps, New Zealand. Although glacial-drainage capture has previously been inferred in the range, our numerical glacier model provides the first quantitative demonstration that this process drives larger variations in discharge for a longer duration than those that occur due to climate change alone. During the Last Glacial Maximum, the effective drainage area of the Ashburton catchment increased to 160% of the interglacial value with drainage capture, driving an increase in discharge exceeding that resulting from glacier recession. Glacial-drainage capture is distinct from traditional (base level–driven) drainage capture and is often unrecognized in proglacial deposits, complicating interpretation of the sedimentary record of climate change.

  17. Facebook Applications' Installation and Removal: A Temporal Analysis

    E-Print Network [OSTI]

    Kagan, Dima; Elyashar, Aviad; Elovici, Yuval

    2013-01-01T23:59:59.000Z

    Facebook applications are one of the reasons for Facebook attractiveness. Unfortunately, numerous users are not aware of the fact that many malicious Facebook applications exist. To educate users, to raise users' awareness and to improve Facebook users' security and privacy, we developed a Firefox add-on that alerts users to the number of installed applications on their Facebook profiles. In this study, we present the temporal analysis of the Facebook applications' installation and removal dataset collected by our add-on. This dataset consists of information from 2,945 users, collected during a period of over a year. We used linear regression to analyze our dataset and discovered the linear connection between the average percentage change of newly installed Facebook applications and the number of days passed since the user initially installed our add-on. Additionally, we found out that users who used our Firefox add-on become more aware of their security and privacy installing on average fewer new application...

  18. Primordial black holes from temporally enhanced curvature perturbation

    E-Print Network [OSTI]

    Teruaki Suyama; Yi-Peng Wu; Jun'ichi Yokoyama

    2014-06-02T23:59:59.000Z

    Scalar field with generalized kinetic interactions metamorphoses depending on its field value, ranging from cosmological constant to stiff matter. We show that such a scalar field can give rise to temporal enhancement of the curvature perturbation in the primordial Universe, leading to efficient production of primordial black holes while the enhancement persists. If the inflation energy scale is high, those mini-black holes evaporate by the Hawking radiation much before Big Bang nucleosynthesis and the effective reheating of the Universe is achieved by the black hole evaporation. Dominance of PBHs and the reheating by their evaporation modify the expansion history of the primordial Universe. This results in a characteristic feature of the spectrum of primordial tensor modes in the DECIGO frequency band, opening an interesting possibility of testing PBH reheating scenario by measuring the primordial tensor modes. If the inflation energy scale is low, the PBH mass can be much larger than the solar mass. In this case, PBH is an interesting candidate for seeds for supermassive black holes residing in present galaxies.

  19. Flow Rate Measurements Using Flow-Induced Pipe Vibration

    SciTech Connect (OSTI)

    R. P. Evans; Jonathan D. Blotter; Alan G. Stephens

    2004-03-01T23:59:59.000Z

    This paper focuses on the possibility of a non-intrusive, low cost, flow rate measurement technique. The technique is based on signal noise from an accelerometer attached to the surface of the pipe. The signal noise is defined as the standard deviation of the frequency averaged time series signal. Experimental results are presented that indicate a nearly quadratic relationship between the signal noise and mass flow rate in the pipe. It is also shown that the signal noise - flow rate relationship is dependant on the pipe material and diameter.

  20. US energy flow - 1984

    SciTech Connect (OSTI)

    Briggs, C.K.; Borg, I.Y.

    1985-07-01T23:59:59.000Z

    The 1984 energy flow diagram for the USA has been constructed using Department of Energy data. It is a convenient graphical device to show supply and demand as well as the size of end-use sectors. A 4% increase in overall energy consumption represented a reversal in a downward trend started in 1979. All indicators pointed to more healthy industrial and farm economies in 1984 than in the previous two years, which accounted for some part of the increase in energy use. While domestic crude oil production remained stable, oil imports rose eight percent also reversing a long-standing trend. Seventy-two million barrels of oil primarily from Mexico and the United Kingdom were added to the Strategic Petroleum Reserve bringing the total oil stored at year end to 451 million barrels. At the same time 49 million barrels of oil were produced from the government-owned Naval Petroleum Reserve No. 1 (Elk Hills, CA). Energy use in all end-use sectors grew in 1984 which is in keeping with increases in use of all types of fossil fuels as well as electricity. Increase in electrical power demand continued to exceed forecasts, and during 1984 contracts for imports to the northeast US were negotiated with Canada. Nuclear power contributed 15% of total power generated in the US. At year end there were 86 licensed reactors and 44 in either start-up or construction stages. Six were canceled or abandoned during construction during the year. 11 refs., 4 figs., 3 tabs.

  1. Population genetic variation in gene expression is associated withphenotypic variation in Saccharomyces cerevisiae

    SciTech Connect (OSTI)

    Fay, Justin C.; McCullough, Heather L.; Sniegowski, Paul D.; Eisen, Michael B.

    2004-02-25T23:59:59.000Z

    The relationship between genetic variation in gene expression and phenotypic variation observable in nature is not well understood. Identifying how many phenotypes are associated with differences in gene expression and how many gene-expression differences are associated with a phenotype is important to understanding the molecular basis and evolution of complex traits. Results: We compared levels of gene expression among nine natural isolates of Saccharomyces cerevisiae grown either in the presence or absence of copper sulfate. Of the nine strains, two show a reduced growth rate and two others are rust colored in the presence of copper sulfate. We identified 633 genes that show significant differences in expression among strains. Of these genes,20 were correlated with resistance to copper sulfate and 24 were correlated with rust coloration. The function of these genes in combination with their expression pattern suggests the presence of both correlative and causative expression differences. But the majority of differentially expressed genes were not correlated with either phenotype and showed the same expression pattern both in the presence and absence of copper sulfate. To determine whether these expression differences may contribute to phenotypic variation under other environmental conditions, we examined one phenotype, freeze tolerance, predicted by the differential expression of the aquaporin gene AQY2. We found freeze tolerance is associated with the expression of AQY2. Conclusions: Gene expression differences provide substantial insight into the molecular basis of naturally occurring traits and can be used to predict environment dependent phenotypic variation.

  2. 1100 IEEE TRANSACTIONS ON NEURAL NETWORKS, VOL. 15, NO. 5, SEPTEMBER 2004 Temporal Codes and Computations for Sensory

    E-Print Network [OSTI]

    Cariani, Peter

    potential implications of temporal codes and computations for new kinds of neural networks are explored and computations that different temporal codes afford, rather than respective information transmission capac- ities1100 IEEE TRANSACTIONS ON NEURAL NETWORKS, VOL. 15, NO. 5, SEPTEMBER 2004 Temporal Codes

  3. Spectral, temporal and temperature features of the nonlinear response of high-temperature superconductors in transient nonlinear spectroscopy

    SciTech Connect (OSTI)

    Bobyrev, Yu V; Petnikova, V M; Rudenko, K V; Shuvalov, Vladimir V [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2006-10-31T23:59:59.000Z

    It is shown that basic properties of the nonlinear response of high-temperature superconductors (HTSCs) observed in femtosecond and picosecond pump-probe experiments at high and low pump levels in various variants of the pump-probe spectroscopy, including one- and two-photon excited-state probing, can be interpreted by using two assumptions. The spectral and temperature properties of the HTSC response at low pump levels can be explained taking into account the contributions from interband electronic transitions to the dielectric constant. At the same time, drastic variations in the HTSC response kinetics (temporal features) observed at high pump levels (for a typical pump pulse energy of {approx}10{sup -7} J in a focal spot of diameter 150 {mu}m) can be explained by assuming the existence of a 'frozen' (metastable) energy gap in the electronic spectrum of a HTSC. In this case, all the conditions required for the interpretation of a drastic decrease in the relaxation rate of a nonlinear response (degeneracy) are realised due to the specific distribution of the electronic state density immediately after the formation of the energy gap in the electronic spectrum of the HTSC. (review)

  4. High speed flow cytometer droplet formation system and method

    DOE Patents [OSTI]

    Van den Engh, Ger (Seattle, WA)

    2000-01-01T23:59:59.000Z

    A droplet forming flow cytometer system allows high speed processing without the need for high oscillator drive powers through the inclusion of an oscillator or piezoelectric crystal such as within the nozzle volume or otherwise unidirectionally coupled to the sheath fluid. The nozzle container continuously converges so as to amplify unidirectional oscillations which are transmitted as pressure waves through the nozzle volume to the nozzle exit so as to form droplets from the fluid jet. The oscillator is directionally isolated so as to avoid moving the entire nozzle container so as to create only pressure waves within the sheath fluid. A variation in substance concentration is achieved through a movable substance introduction port which is positioned within a convergence zone to vary the relative concentration of substance to sheath fluid while still maintaining optimal laminar flow conditions. This variation may be automatically controlled through a sensor and controller configuration. A replaceable tip design is also provided whereby the ceramic nozzle tip is positioned within an edge insert in the nozzle body so as to smoothly transition from nozzle body to nozzle tip. The nozzle tip is sealed against its outer surface to the nozzle body so it may be removable for cleaning or replacement.

  5. Ceramic Cross Flow Recuperator Design Parameters

    E-Print Network [OSTI]

    Gonzalez, J. M.; Rebello, W. J.

    1981-01-01T23:59:59.000Z

    the performance of the ceramic recuperator in various industrial furnaces. The ceramic cross flow recuperator core has multiple rectangular flow passages (perpendicular to each other) for the air and gas. Various flow passages are available contingent upon...

  6. Two phase flow in capillary tubes

    E-Print Network [OSTI]

    Suo, Mikio

    1963-01-01T23:59:59.000Z

    The flow of two phases, gas and liquid, has been studied in horizontal tubes of capillary diameter. The flow has been primarily studied in the regime where the gas flows as long bubbles separated from the wall of the tube ...

  7. Insertable fluid flow passage bridgepiece and method

    DOE Patents [OSTI]

    Jones, Daniel O. (Glenville, NV)

    2000-01-01T23:59:59.000Z

    A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.

  8. Probing spectral-temporal correlations with a versatile integrated source of parametric down-conversion states

    E-Print Network [OSTI]

    Vahid Ansari; Benjamin Brecht; Georg Harder; Christine Silberhorn

    2015-01-20T23:59:59.000Z

    The spectral-temporal correlation and the correlation time of a biphoton wavepacket generated in the process of parametric down-conversion (PDC), is of great importance for a broad range of quantum experiments. We utilise an integrated PDC source to generate biphotons with different types of spectral-temporal correlations and probe their respective correlation times. The outcomes confirms that the correlation time is independent of the coherence time of the pump light, and it is only determined by the waveguide length and its dispersion properties. Furthermore, we investigate the properties of the PDC biphoton wavepacket exhibiting different types of spectral-temporal correlations and their suitability for quantum-enhanced applications.

  9. Flow distribution channels to control flow in process channels

    DOE Patents [OSTI]

    Tonkovich, Anna Lee; Arora, Ravi; Kilanowski, David

    2014-10-28T23:59:59.000Z

    The invention describes features that can be used to control flow to an array of microchannels. The invention also describes methods in which a process stream is distributed to plural microchannels.

  10. The transition from two phase bubble flow to slug flow

    E-Print Network [OSTI]

    Radovcich, Nick A.

    1962-01-01T23:59:59.000Z

    The process of transition from bubble to slug flow in a vertical pipe has been studied analytically and experimentally. An equation is presented which gives the agglomeration time as a function of void fraction, channel ...

  11. Complete Chaotic Mixing in an Electro-osmotic Flow by Destabilization of Key Periodic Pathlines

    E-Print Network [OSTI]

    R. Chabreyrie; C. Chandre; P. Singh; N. Aubry

    2011-02-07T23:59:59.000Z

    The ability to generate complete, or almost complete, chaotic mixing is of great interest in numerous applications, particularly for microfluidics. For this purpose, we propose a strategy that allows us to quickly target the parameter values at which complete mixing occurs. The technique is applied to a time periodic, two-dimensional electro-osmotic flow with spatially and temporally varying Helmoltz-Smoluchowski slip boundary conditions. The strategy consists of following the linear stability of some key periodic pathlines in parameter space (i.e., amplitude and frequency of the forcing), particularly through the bifurcation points at which such pathlines become unstable.

  12. Development and verification of a numerical simulator to calculate the bottom hole flowing pressures in multiphase systems

    E-Print Network [OSTI]

    Rasool, Syed Ahmed

    1994-01-01T23:59:59.000Z

    the Middle East, but there were some wells located in offshore Louisiana. There was a wide range Of variation in the variables for each well, some of these were: flow rates, gas/oil ratios, total depths, tubing sizes, fluid Compositions, and water cuts...

  13. Thermocapillary Flow on Superhydrophobic Surfaces

    E-Print Network [OSTI]

    Baier, Tobias; Hardt, Steffen

    2010-01-01T23:59:59.000Z

    A liquid in Cassie-Baxter state above a structured superhydrophobic surface is ideally suited for surface driven transport due to its large free surface fraction in close contact to a solid. We investigate thermal Marangoni flow over a superhydrophobic array of fins oriented parallel or perpendicular to an applied temperature gradient. In the Stokes limit we derive an analytical expression for the bulk flow velocity above the surface and compare it with numerical solutions of the Navier-Stokes equation. Even for moderate temperature gradients comparatively large flow velocities are induced, suggesting to utilize this principle for microfluidic pumping.

  14. Ultra-Short Electron Bunch and X-Ray Temporal Diagnostics with an X-Band Transverse Deflector

    SciTech Connect (OSTI)

    Ding, Y.; Emma, P.; Frisch, J.; Huang, Z.; Loos, H.; Krejcik, P.; Wang, M-H.; /SLAC; Behrens, C.; /DESY

    2011-12-13T23:59:59.000Z

    The measurement of ultra-short electron bunches on the femtosecond time scale constitutes a very challenging problem. In X-ray free-electron laser facilities such as the Linac Coherent Light Source (LCLS), generation of sub-ten femtosecond X-ray pulses is possible, and some efforts have been put into both ultra-short electron and X-ray beam diagnostics. Here we propose a single-shot method using a transverse rf deflector (X-band) after the undulator to reconstruct both the electron bunch and X-ray temporal profiles. Simulation studies show that about 1 fs (rms) time resolution may be achievable in the LCLS and is applicable to a wide range of FEL wavelengths and pulse lengths. The jitter, resolution and other related issues will be discussed. The successful operation of the Linac Coherent Light Source (LCLS), with its capability of generating free-electron laser (FEL) X-ray pulses from a few femtoseconds (fs) up to a few hundred fs, opens up vast opportunities for studying atoms and molecules on this unprecedented ultrashort time scale. However, tremendous challenges remain in the measurement and control of these ultrashort pulses with femtosecond precision, for both the electron beam (e-beam) and the X-ray pulses. For ultrashort e-beam bunch length measurements, a standard method has been established at LCLS using an S-band radio-frequency (rf) deflector, which works like a streak camera for electrons and is capable of resolving bunch lengths as short as {approx} 10 fs rms. However, the e-beam with low charges of 20 pC at LCLS, which is expected to be less than 10 fs in duration, is too short to be measured using this transverse deflector. The measurement of the electron bunch length is helpful in estimating the FEL X-ray pulse duration. However, for a realistic beam, such as that with a Gaussian shape or even a spiky profile, the FEL amplification varies along the bunch due to peak current or emittance variation. This will cause differences between the temporal shape or duration of the electron bunch and the X-ray pulse. Initial experiments at LCLS have revealed that characterization of the X-ray pulse duration on a shot-by-shot basis is critical for the interpretation of the data. However, a reliable x-ray pulse temporal diagnostic tool is not available so far at the LCLS. We propose a novel method in this paper to characterize the FEL X-ray pulse duration and shape. A transverse rf deflector is used in conjunction with an e-beam energy spectrometer, located after the FEL undulator. By measuring the difference in the e-beam longitudinal phase space between FEL-on and FEL-off, we can obtain the time-resolved energy loss and energy spread induced from the FEL radiation, allowing the FEL X-ray temporal shape to be reconstructed.

  15. Frictional granular mechanics: A variational approach

    SciTech Connect (OSTI)

    Holtzman, R.; Silin, D.B.; Patzek, T.W.

    2009-10-16T23:59:59.000Z

    The mechanical properties of a cohesionless granular material are evaluated from grain-scale simulations. Intergranular interactions, including friction and sliding, are modeled by a set of contact rules based on the theories of Hertz, Mindlin, and Deresiewicz. A computer generated, three-dimensional, irregular pack of spherical grains is loaded by incremental displacement of its boundaries. Deformation is described by a sequence of static equilibrium configurations of the pack. A variational approach is employed to find the equilibrium configurations by minimizing the total work against the intergranular loads. Effective elastic moduli are evaluated from the intergranular forces and the deformation of the pack. Good agreement between the computed and measured moduli, achieved with no adjustment of material parameters, establishes the physical soundness of the proposed model.

  16. A Novel Variational Principle arising from Electromagnetism

    E-Print Network [OSTI]

    Hanzhong Wu

    2009-05-06T23:59:59.000Z

    Analyzing one example of LC circuit in [8], show its Lagrange problem only have other type critical points except for minimum type and maximum type under many circumstances. One novel variational principle is established instead of Pontryagin maximum principle or other extremal principles to be suitable for all types of critical points in nonlinear LC circuits. The generalized Euler-Lagrange equation of new form is derived. The canonical Hamiltonian systems of description are also obtained under the Legendre transformation, instead of the generalized type of Hamiltonian systems. This approach is not only very simple in theory but also convenient in applications and applicable for nonlinear LC circuits with arbitrary topology and other additional integral constraints.

  17. UPRE method for total variation parameter selection

    SciTech Connect (OSTI)

    Wohlberg, Brendt [Los Alamos National Laboratory; Lin, Youzuo [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    Total Variation (TV) Regularization is an important method for solving a wide variety of inverse problems in image processing. In order to optimize the reconstructed image, it is important to choose the optimal regularization parameter. The Unbiased Predictive Risk Estimator (UPRE) has been shown to give a very good estimate of this parameter for Tikhonov Regularization. In this paper we propose an approach to extend UPRE method to the TV problem. However, applying the extended UPRE is impractical in the case of inverse problems such as de blurring, due to the large scale of the associated linear problem. We also propose an approach to reducing the large scale problem to a small problem, significantly reducing computational requirements while providing a good approximation to the original problem.

  18. Exploring multi-layer flow network of international trade based on flow distances

    E-Print Network [OSTI]

    Shen, Bin; Zheng, Qiuhua

    2015-01-01T23:59:59.000Z

    Based on the approach of flow distances, the international trade flow system is studied from the perspective of multi-layer flow network. A model of multi-layer flow network is proposed for modelling and analyzing multiple types of flows in flow systems. Then, flow distances are introduced, and symmetric minimum flow distance is presented. Subsequently, we discuss the establishment of the multi-layer flow networks of international trade from two coupled viewpoints, i.e., the viewpoint of commodity flow and that of money flow. Thus, the multi-layer flow networks of international trade is explored. First, trading "trophic levels" are adopted to depict positions that economies occupied in the flow network. We find that the distributions of trading "trophic levels" have the similar clustering pattern for different types of commodity, and there are some regularities between money flow network and commodity flow network. Second, we find that active and competitive countries trade a wide spectrum of products, while ...

  19. Bacterial Community Succession During in situ Uranium Bioremediation: Spatial Similarities Along Controlled Flow Paths

    SciTech Connect (OSTI)

    Hwang, Chiachi; Wu, Weimin; Gentry, Terry J.; Carley, Jack; Corbin, Gail A.; Carroll, Sue L.; Watson, David B.; Jardine, Phil M.; Zhou, Jizhong; Criddle, Craig S.; Fields, Matthew W.

    2009-05-22T23:59:59.000Z

    Bacterial community succession was investigated in a field-scale subsurface reactor formed by a series of wells that received weekly ethanol additions to re-circulating groundwater. Ethanol additions stimulated denitrification, metal reduction, sulfate reduction, and U(VI) reduction to sparingly soluble U(IV). Clone libraries of SSU rRNA gene sequences from groundwater samples enabled tracking of spatial and temporal changes over a 1.5 y period. Analyses showed that the communities changed in a manner consistent with geochemical variations that occurred along temporal and spatial scales. Canonical correspondence analysis revealed that the levels of nitrate, uranium, sulfide, sulfate, and ethanol strongly correlated with particular bacterial populations. As sulfate and U(VI) levels declined, sequences representative of sulfate-reducers and metal-reducers were detected at high levels. Ultimately, sequences associated with sulfate-reducing populations predominated, and sulfate levels declined as U(VI) remained at low levels. When engineering controls were compared to the population variation via canonical ordination, changes could be related to dissolved oxygen control and ethanol addition. The data also indicated that the indigenous populations responded differently to stimulation for bio-reduction; however, the two bio-stimulated communities became more similar after different transitions in an idiosyncratic manner. The strong associations between particular environmental variables and certain populations provide insight into the establishment of practical and successful remediation strategies in radionuclide-contaminated environments with respect to engineering controls and microbial ecology.

  20. Colorado: Isothermal Battery Calorimeter Quantifies Heat Flow...

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

    Isothermal Battery Calorimeter Quantifies Heat Flow, Helps Make Safer, Longer-lasting Batteries Colorado: Isothermal Battery Calorimeter Quantifies Heat Flow, Helps Make Safer,...