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Note: This page contains sample records for the topic "discrete atmospheric conditions" from the National Library of EnergyBeta (NLEBeta).
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1

Discrete Packet Analysis for Improved Atmospheric Rejection on Modulated Laser Signals  

SciTech Connect

This slide-show discusses how the method of discrete packet analysis improves atmospheric compensation for quasi-CW fluorescence detection methods. This is key to improving remote sensing capabilities.

O'Neill, M., McKenna, I., DiBenedetto, J., Capelle, G., Trainham, R.

2012-07-19T23:59:59.000Z

2

DISCRETE TRANSPARENT BOUNDARY CONDITIONS FOR WIDE ANGLE PARABOLIC EQUATIONS IN UNDERWATER  

E-Print Network (OSTI)

DISCRETE TRANSPARENT BOUNDARY CONDITIONS FOR WIDE ANGLE PARABOLIC EQUATIONS IN UNDERWATER ACOUSTICS "parabolic" equations (WAPEs) in underwater acoustics (assuming cylindrical symmetry). Existing the discretization of transparent bottom boundary conditions. In oceanography one wants to calculate the underwater

Ehrhardt, Matthias

3

Vertical Coordinate Transformation of Vertically-Discretized Atmospheric Fields  

Science Conference Proceedings (OSTI)

The problem of transforming fields of atmospheric variables from one vertical coordinate system to another without altering their dynamic balance is discussed. A curve fitting scheme applied to the data points in each grid column is proposed ...

Rainer Bleck

1984-12-01T23:59:59.000Z

4

Discrete second order adjoints in atmospheric chemical transport modeling  

Science Conference Proceedings (OSTI)

Atmospheric chemical transport models (CTMs) are essential tools for the study of air pollution, for environmental policy decisions, for the interpretation of observational data, and for producing air quality forecasts. Many air quality studies require ... Keywords: 65, Chemical transport models, Hessian singular vectors, Optimization, Second order adjoints, Sensitivity analysis, Stiff equations

Adrian Sandu; Lin Zhang

2008-06-01T23:59:59.000Z

5

On Robust Estimation of Low-Frequency Variability Trends in Discrete Markovian Sequences of Atmospheric Circulation Patterns  

Science Conference Proceedings (OSTI)

Identification and analysis of temporal trends and low-frequency variability in discrete time series is an important practical topic in the understanding and prediction of many atmospheric processes, for example, in analysis of climate change. ...

Illia Horenko

2009-07-01T23:59:59.000Z

6

HYPERsensarium : an archive of atmospheric conditions  

E-Print Network (OSTI)

HYPERsensarium proposes a tangible interface of atmospheres for public experience through an archive of historical and projected weathers. While architecture's purpose has long been to act as the technical boundary between ...

Shaw, Kelly E. (Kelly Evelyn)

2013-01-01T23:59:59.000Z

7

A Discrete Ordinate, Multiple Scattering, Radiative Transfer Model of the Venus Atmosphere from 0.1 to 260 ?m  

Science Conference Proceedings (OSTI)

The authors describe a new radiative transfer model of the Venus atmosphere (RTM) that includes optical properties from nine gases and four cloud modes between 0.1 and 260 ?m. A multiple-stream discrete ordinate flux solver is used to calculate ...

Christopher Lee; Mark Ian Richardson

2011-06-01T23:59:59.000Z

8

The Moist Available Energy of a Conditionally Unstable Atmosphere  

Science Conference Proceedings (OSTI)

The concept of “moist available energy,” defined by Lorenz, is applied to study the potential energy available for cumulus convection in a conditionally unstable atmosphere. A modified version of Lorenz's parcel-moving algorithm is applied to the ...

David A. Randall; Junyi Wang

1992-02-01T23:59:59.000Z

9

Conditional Sampling of Turbulence in the Atmospheric Surface Layer  

Science Conference Proceedings (OSTI)

Conditional sampling and averaging techniques are used to obtain statistics of convectively-driven quasi-ordered structures at a height of 4 m within the atmospheric surface layer. The fraction of time 'y occupiedby these structures, and their ...

R. A. Antonia; S. Rajagopalan; A. J. Chambers

1983-01-01T23:59:59.000Z

10

Study of Laser Scintillation in Different Atmospheric Conditions  

Science Conference Proceedings (OSTI)

Laser scintillation observations were carried out over a flat surface in different atmospheric conditions on 33 separate days during March 1990?April 1991 and were analyzed and studied. The principal results of the analysis reveal (i) marked ...

P. Ernest Raj; S. Sharma; P. C. S. Devara; G. Pandithurai

1993-06-01T23:59:59.000Z

11

The Spherical Harmonics Discrete Ordinate Method for Three-Dimensional Atmospheric Radiative Transfer  

Science Conference Proceedings (OSTI)

A new algorithm for modeling radiative transfer in inhomogeneous three-dimensional media is described. The spherical harmonics discrete ordinate method uses a spherical harmonic angular representation to reduce memory use and time computing the ...

K. Franklin Evans

1998-02-01T23:59:59.000Z

12

A New Look at the Discrete Ordinate Method for Radiative Transfer Calculations in Anisotropically Scattering Atmospheres  

Science Conference Proceedings (OSTI)

The difficulties inherent in the conventional numerical implementation of the discrete ordinate method (following Chandrasekhar's prescription) for solving the radiative transfer equation are discussed. A matrix formulation is developed to ...

Knut Stamnes; Roy A. Swanson

1981-02-01T23:59:59.000Z

13

Calculation of the cumulative reaction probability via a discrete variable representation with absorbing boundary conditions  

SciTech Connect

A new method is suggested for the calculation of the microcanonical cumulative reaction probability {ital via} flux autocorrelation relations. The Hamiltonian and the flux operators are computed in a discrete variable representation (DVR) and a well-behaved representation for the Green's operator, {ital G}({ital E}{sup +}), is obtained by imposing absorbing boundary conditions (ABC). Applications to a one-dimensional-model problem and to the collinear H+H{sub 2} reaction show that the DVR-ABC scheme provides a very efficient method for the {ital direct} calculation of the microcanonical probability, circumventing the need to compute the state-to-state dynamics. Our results indicate that the cumulative reaction probability can be calculated to a high accuracy using a rather small number of DVR points, confined to the vicinity of the transition state. Only limited information regarding the potential-energy surface is therefore required, suggesting that this method would be applicable also to higher dimensionality problems, for which the complete potential surface is often unknown.

Seideman, T.; Miller, W.H. (Department of Chemistry, University of California, Berkeley, California 94720 (United States))

1992-03-15T23:59:59.000Z

14

An Analysis of the Conditional Instability of the Tropical Atmosphere  

Science Conference Proceedings (OSTI)

The ice phase is included in thermodynamic calculations of convective available potential energy (CAPE) for a large number of soundings in the tropical atmosphere, at both land and ocean stations. It is found that the positive-buoyancy ...

Erle Williams; Nilton Renno

1993-01-01T23:59:59.000Z

15

A Discrete Gust Model for Use in the Design of Wind Energy Conversion Systems  

Science Conference Proceedings (OSTI)

Discrete gust models, although idealizations of actual atmospheric conditions, are useful for engineering design. For fatigue design, these models must be representative of the conditions a structure or vehicle will experience on a continuous ...

Walter Frost; Robert E. Turner

1982-06-01T23:59:59.000Z

16

Spectral Decomposition of Two-Dimensional Atmospheric Fields on Limited-Area Domains Using the Discrete Cosine Transform (DCT)  

Science Conference Proceedings (OSTI)

For most atmospheric fields, the larger part of the spatial variance is contained in the planetary scales. When examined over a limited area, these atmospheric fields exhibit an aperiodic structure, with large trends across the domain. Trying to ...

Bertrand Denis; Jean Côté; René Laprise

2002-07-01T23:59:59.000Z

17

Fluorescence emission induced by extensive air showers in dependence on atmospheric conditions  

E-Print Network (OSTI)

Charged particles of extensive air showers (EAS), mainly electrons and positrons, initiate the emission of fluorescence light in the Earth's atmosphere. This light provides a calorimetric measurement of the energy of cosmic rays. For reconstructing the primary energy from an observed light track of an EAS, the fluorescence yield in air has to be known in dependence on atmospheric conditions, like air temperature, pressure, and humidity. Several experiments on fluorescence emission have published various sets of data covering different parts of the dependence of the fluorescence yield on atmospheric conditions. Using a compilation of published measurements, a calculation of the fluorescence yield in dependence on altitude is presented. The fluorescence calculation is applied to simulated air showers and different atmospheric profiles to estimate the influence of the atmospheric conditions on the reconstructed shower parameters.

Keilhauer, Bianca

2009-01-01T23:59:59.000Z

18

Computational and conditioning issues of a discrete model for cochlear sensorineural hypoacusia  

Science Conference Proceedings (OSTI)

The interest of inner ear research towards the cochlear simulation is due to the lack of imaging techniques for human noninvasive investigation. Unfortunately, in case of Sensorineural Hearing Loss (SHL), the majority of the models developed in the literature ... Keywords: Cochlear modeling, Conditioning, Integrodifferential models, Iterative methods

Daniele Bertaccini; Stefano Fanelli

2009-08-01T23:59:59.000Z

19

Atmospheric Dispersion Model Validation in Low Wind Conditions  

DOE Green Energy (OSTI)

and SCIPUFF models and under-prediction bias by the ALOHA model. The experiment parameters were for near field dispersion (less than 100 meters) in low wind speed conditions (less than 2 meters per second).

Patrick Sawyer

2007-11-01T23:59:59.000Z

20

Conditional Sampling of Updrafts and Downdrafts in the Marine Atmospheric Boundary Layer  

Science Conference Proceedings (OSTI)

The properties of updrafts and downdrafts in the lower third of the marine atmospheric boundary layer (MABL) over the central Pacific Ocean are investigated using a conditional sampling technique. When the drafts are classified according to their ...

Siri Jodha Singh Khalsa; Gary K. Greenhut

1985-12-01T23:59:59.000Z

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


21

Stability Parameters and Wind-Stress Coefficients under Various Atmospheric Conditions  

Science Conference Proceedings (OSTI)

Stability parameters and wind-stress coefficients under various atmospheric conditions are related to wind velocity and air-sea temperature difference. Readily applicable formulae, without iterative computations, of wind-stress coefficients under ...

Jin Wu

1986-06-01T23:59:59.000Z

22

Effects of Initial and Boundary Conditions of Mesoscale Models on Simulated Atmospheric Refractivity  

Science Conference Proceedings (OSTI)

Radar ducting is caused by sharp vertical changes in temperature and, especially, water vapor at the top of the atmospheric boundary layer, both of which are sensitive to variations in the underlying surface conditions, local mesoscale weather, ...

Changgui Wang; Damian Wilson; Tracy Haack; Peter Clark; Humphrey Lean; Robert Marshall

2012-01-01T23:59:59.000Z

23

The Regional Atmospheric Water Budget over Southwestern Germany under Different Synoptic Conditions  

Science Conference Proceedings (OSTI)

This study addresses the question of how complex topography in a low-mountain region affects the partitioning and the variability of the atmospheric water budget components (WBCs) as a function of synoptic-scale flow conditions. The WBCs are ...

Romi Sasse; Gerd Schädler; Christoph Kottmeier

2013-02-01T23:59:59.000Z

24

Surface Turbulent Flux Formulation in Stable Conditions for Atmospheric Circulation Models  

Science Conference Proceedings (OSTI)

The forty-day Wangara data set is used to discuss the applicability of the traditional formulations for the surface fluxes for atmospheric circulation models. It is shown that, while in unstable conditions the surface layer relationships can be ...

Yves Delage

1985-01-01T23:59:59.000Z

25

Description of Atmospheric Conditions at the Pierre Auger Observatory using the Global Data Assimilation System (GDAS)  

Science Conference Proceedings (OSTI)

Atmospheric conditions at the site of a cosmic ray observatory must be known for reconstructing observed extensive air showers. The Global Data Assimilation System (GDAS) is a global atmospheric model predicated on meteorological measurements and numerical weather predictions. GDAS provides altitude-dependent profiles of the main state variables of the atmosphere like temperature, pressure, and humidity. The original data and their application to the air shower reconstruction of the Pierre Auger Observatory are described. By comparisons with radiosonde and weather station measurements obtained on-site in Malargue and averaged monthly models, the utility of the GDAS data is shown.

Abreu, P.; /Lisbon, IST; Aglietta, M.; /Turin U. /INFN, Turin; Ahlers, M.; /Wisconsin U., Madison; Ahn, E.J.; /Fermilab; Albuquerque, I.F.M.; /Sao Paulo U.; Allard, D.; /APC, Paris; Allekotte, I.; /Buenos Aires, CONICET; Allen, J.; /New York U.; Allison, P.; /Ohio State U.; Almela, A.; /Natl. Tech. U., San Nicolas /Buenos Aires, CONICET; Alvarez Castillo, J.; /Mexico U., ICN /Santiago de Compostela U.

2012-01-01T23:59:59.000Z

26

Wind Turbines Under Atmospheric Icing Conditions - Ice Accretion Modeling, Aerodynamics, and Control Strategies for Mitigating Performance Degradation.  

E-Print Network (OSTI)

??This thesis presents a combined engineering methodology of ice accretion, airfoil data, and rotor performance analysis of wind turbines subject to moderate atmospheric icing conditions.… (more)

Brillembourg, Dwight

2013-01-01T23:59:59.000Z

27

Influences of atmospheric conditions and air mass on the ratio of ultraviolet to total solar radiation  

SciTech Connect

The technology to detoxify hazardous wastes using ultraviolet (UV) solar radiation is being investigated by the DOE/SERI Solar Thermal Technology Program. One of the elements of the technology evaluation is the assessment and characterization of UV solar radiation resources available for detoxification processes. This report describes the major atmospheric variables that determine the amount of UV solar radiation at the earth's surface, and how the ratio of UV-to-total solar radiation varies with atmospheric conditions. These ratios are calculated from broadband and spectral solar radiation measurements acquired at SERI, and obtained from the literature on modeled and measured UV solar radiation. The following sections discuss the atmospheric effects on UV solar radiation and provide UV-to-total solar radiation ratios from published studies, as well as measured values from SERI's data. A summary and conclusions are also given.

Riordan, C.J.; Hulstrom, R.L.; Myers, D.R.

1990-08-01T23:59:59.000Z

28

On Bäcklund transformations and boundary conditions associated with the quantum inverse problem for a discrete nonlinear integrable system and its connection to Baxter's Q-operator  

E-Print Network (OSTI)

A discrete nonlinear system is analysed in case of open chain boundary conditions at the ends. It is shown that the integrability of the system remains intact, by obtaining a modified set of Lax equations which automatically take care of the boundary conditions. The same Lax pair also conforms to the conditions stipulated by Sklyanin [5]. The quantum inverse problem is set up and the diagonalisation is carried out by the method of sparation of variables. B\\"{a}cklund transformations are then derived under the modified boundary conditions using the classical r-matrix . Finally by quantising the B\\"{a}cklund transformation it is possible to identify the relation satisfied by the eigenvalue of Baxter's Q-operator even for the quasi periodic situation.

A. Ghose Choudhury; A. Roy Chowdhury

2002-02-19T23:59:59.000Z

29

The ISLSCP Initiative I Global Datasets: Surface Boundary Conditions and Atmospheric Forcings for Land-Atmosphere Studies  

Science Conference Proceedings (OSTI)

A comprehensive series of global datasets for land-atmosphere models has been collected, formatted to a common grid, and released on a set of CD-ROMS. This paper describes the motivation for and the, contents of the dataset.

P. J. Sellers; B. W. Meeson; J. Closs; J. Collatz; F. Corprew; D. Dazlich; F. G. Hall; Y. Kerr; R. Koster; S. Los; K. Mitchell; J. McManus; D. Myers; K-J. Sun; P. Try

1996-09-01T23:59:59.000Z

30

The Influence of Atmospheric Noise and Uncertainty in Ocean Initial Conditions on the Limit of Predictability in a Coupled GCM  

Science Conference Proceedings (OSTI)

The influence of atmospheric stochastic forcing and uncertainty in initial conditions on the limit of predictability of the NCEP Climate Forecast System (CFS) is quantified based on comparisons of idealized identical twin prediction experiments ...

Cristiana Stan; Ben P. Kirtman

2008-07-01T23:59:59.000Z

31

An Analysis of Wind Fluctuation Statistics Collected under Stable Atmospheric Conditions at Three Sites in Alberta, Canada  

Science Conference Proceedings (OSTI)

Wind fluctuation data collected under stable atmospheric conditions at two prairie sites and a site located near the Rocky Mountain foothills have been analyzed. Results of the analysis show a marked tendency for horizontal fluctuation angles to ...

D. M. Leahey; M. C. Hansen; M. B. Schroeder

1988-06-01T23:59:59.000Z

32

Estimating Spatial Variability in Atmospheric Properties over Remotely Sensed Land Surface Conditions  

Science Conference Proceedings (OSTI)

This paper investigates the spatial relationships between surface fluxes and near-surface atmospheric properties (AP), and the potential errors in flux estimation due to homogeneous atmospheric inputs over heterogeneous landscapes. A large-eddy ...

Giacomo Bertoldi; William P. Kustas; John D. Albertson

2008-08-01T23:59:59.000Z

33

Conditional Sampling of Coherent Structures in Atmospheric Turbulence Using the Wavelet Transform  

Science Conference Proceedings (OSTI)

The development and evaluation of a technique to detect and retrieve coherent structures embedded in a record of atmospheric surface-layer temperature fluctuations is described. This new detection scheme, based on a local wavelet transform, is ...

B. J. Turner; M. Y. Leclerc

1994-02-01T23:59:59.000Z

34

Large Eddy Simulation of an Inhomogeneous Atmospheric Boundary Layer under Neutral Conditions  

Science Conference Proceedings (OSTI)

Flow structures in an inhomogeneous neutrally stratified atmospheric boundary layer flow, obtained from large eddy simulation, are analyzed and compared with homogeneous case counterparts. The inhomogeneity is imposed in the streamwise direction ...

Ching-Long Lin; John W. Glendening

2002-08-01T23:59:59.000Z

35

Influence of Ocean Surface Conditions on Atmospheric Vertical Thermodynamic Structure and Deep Convection  

Science Conference Proceedings (OSTI)

The authors analyze the influence of sea surface temperature (SST) and surface wind divergence on atmospheric thermodynamic structure and the resulting effects on the occurrence of deep convection using National Meteorological Center radiosonde ...

Rong Fu; Anthony D. Del Genio; William B. Rossow

1994-07-01T23:59:59.000Z

36

The Soil Moisture–Atmosphere Coupling Experiment (SMACEX): Background, Hydrometeorological Conditions, and Preliminary Findings  

Science Conference Proceedings (OSTI)

The Soil Moisture–Atmosphere Coupling Experiment (SMACEX) was conducted in conjunction with the Soil Moisture Experiment 2002 (SMEX02) during June and July 2002 near Ames, Iowa—a corn and soybean production region. The primary objective of SMEX02 ...

William P. Kustas; Jerry L. Hatfield; John H. Prueger

2005-12-01T23:59:59.000Z

37

E – ? model of spray-laden near-sea atmospheric layer in high wind conditions  

Science Conference Proceedings (OSTI)

In-depth understanding and accurate modelling of the interaction between ocean spray and a turbulent flow under high-wind conditions is essential for improving intensity forecasts of hurricanes and severe storms. Here we consider the E – ? closure ...

Yevgenii Rastigejev; Sergey A. Suslov

38

A STUDY ON LEGIONELLA PNEUMOPHILA, WATER CHEMISTRY, AND ATMOSPHERIC CONDITIONS IN COOLING TOWERS AT THE SAVANNAH RIVER SITE  

SciTech Connect

Legionnaires disease is a pneumonia caused by the inhalation of the bacterium Legionella pneumophila. The majority of illnesses have been associated with cooling towers since these devices can harbor and disseminate the bacterium in the aerosolized mist generated by these systems. Historically, Savannah River Site (SRS) cooling towers have had occurrences of elevated levels of Legionella in all seasons of the year and in patterns that are difficult to predict. Since elevated Legionella in cooling tower water are a potential health concern a question has been raised as to the best control methodology. In this work we analyze available chemical, biological, and atmospheric data to determine the best method or key parameter for control. The SRS 4Q Industrial Hygiene Manual, 4Q-1203, 1 - G Cooling Tower Operation and the SRNL Legionella Sampling Program, states that 'Participation in the SRNL Legionella Sampling Program is MANDATORY for all operating cooling towers'. The resulting reports include L. pneumophila concentration information in cells/L. L. pneumophila concentrations >10{sup 7} cells/L are considered elevated and unsafe so action must be taken to reduce these densities. These remedial actions typically include increase biocide addition or 'shocking'. Sometimes additional actions are required if the problem persists including increase tower maintenance (e.g. cleaning). Evaluation of 14 SRS cooling towers, seven water quality parameters, and five Legionella serogroups over a three-plus year time frame demonstrated that cooling tower water Legionella densities varied widely though out this time period. In fact there was no one common consistent significant variable across all towers. The significant factors that did show up most frequently were related to suspended particulates, conductivity, pH, and dissolved oxygen, not chlorine or bromine as might be expected. Analyses of atmospheric data showed that there were more frequent significant elevated Legionella concentrations when the dew point temperature was high--a summertime occurrence. However, analysis of the three years of Legionella monitoring data of the 14 different SRS Cooling Towers demonstrated that elevated concentrations are observed at all temperatures and seasons. The objective of this study is to evaluate the ecology of L. pneumophila including serogroups and population densities, chemical, and atmospheric data, on cooling towers at SRS to determine whether relationships exist among water chemistry, and atmospheric conditions. The goal is to more fully understand the conditions which inhibit or encourage L. pneumophila growth and supply this data and associated recommendations to SRS Cooling Tower personnel for improved management of operation. Hopefully this information could then be used to help control L. pneumophila growth more effectively in SRS cooling tower water.

Smith, C.; Brigmon, R.

2009-10-20T23:59:59.000Z

39

On discrete cosine transform  

E-Print Network (OSTI)

The discrete cosine transform (DCT), introduced by Ahmed, Natarajan and Rao, has been used in many applications of digital signal processing, data compression and information hiding. There are four types of the discrete cosine transform. In simulating the discrete cosine transform, we propose a generalized discrete cosine transform with three parameters, and prove its orthogonality for some new cases. A new type of discrete cosine transform is proposed and its orthogonality is proved. Finally, we propose a generalized discrete W transform with three parameters, and prove its orthogonality for some new cases.

Zhou, Jianqin

2011-01-01T23:59:59.000Z

40

Observations of Secondary Organic Aerosol Production and Soot Aging under Atmospheric Conditions Using a Novel Environmental Aerosol Chamber  

E-Print Network (OSTI)

Secondary organic aerosols (SOA) comprise a substantial fraction of the total global aerosol budget. While laboratory studies involving smog chambers have advanced our understanding of the formation mechanisms responsible for SOA, our knowledge of the processes leading to SOA production under ambient gaseous and particulate concentrations as well as the impact these aerosol types have on climate is poorly understood. Although the majority of atmospheric aerosols scatter radiation either directly or indirectly by serving as cloud condensation nuclei, soot is thought to have a significant warming effect through absorption. Like inorganic salts, soot may undergo atmospheric transformation through the vapor condensation of non-volatile gaseous species which will alter both its chemical and physical properties. Typical smog chamber studies investigating the formation and growth of SOA as well as the soot aging process are temporally limited by the initial gaseous concentrations injected into the chamber environment. Furthermore, data interpretation from such experiments is generally restricted to the singular gaseous species under investigation. This dissertation discusses the use of a new aerosol chamber designed to study the formation and growth of SOA and soot aging under atmospherically relevant conditions. The Ambient Aerosol Chamber for Evolution Studies (AACES) was deployed at three field sites where size and hygroscopic growth factor (HGF) of ammonium sulfate seed particles was monitored over time to examine the formation and growth of SOA. Similar studies investigating the soot aging process were also conducted in Houston, TX. It is shown that during the ambient growth of ammonium sulfate seed particles, as particle size increases, hygroscopic growth factors decrease considerably resulting in a significant organic mass fraction in the particle phase concluding an experiment. Observations of soot aging show an increase in measured size, HGF, mass and single scattering albedo. Ambient growth rate comparisons with chamber growth yielded similar trends verifying the use of AACES to study aerosol aging. Based on the results from this study, it is recommended that AACES be employed in future studies involving the production and growth of SOA and soot aging under ambient conditions in order to bridge the gaps in our current scientific knowledge.

Glen, Crystal

2010-12-01T23:59:59.000Z

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


41

Prediction of Monthly-Mean Temperature: The Roles of Atmospheric and Land Initial Conditions and Sea Surface Temperature  

Science Conference Proceedings (OSTI)

Using the retrospective forecasts from the National Centers for Environmental Prediction (NCEP) coupled atmosphere–ocean Climate Forecast System (CFS) and the Atmospheric Model Intercomparison Project (AMIP) simulations from its uncoupled ...

Mingyue Chen; Wanqiu Wang; Arun Kumar

2010-02-01T23:59:59.000Z

42

Transition of the Large-Scale Atmospheric and Land Surface Conditions from the Dry to the Wet Season over Amazonia as Diagnosed by the ECMWF Re-Analysis  

Science Conference Proceedings (OSTI)

Using 15-yr instantaneous European Centre for Medium-Range Weather Forecasts Re-Analysis (ERA) data, the authors have examined the large-scale atmospheric conditions and the local surface fluxes through the transition periods from the dry to wet ...

Wenhong Li; Rong Fu

2004-07-01T23:59:59.000Z

43

Adaptive Discrete Cosine Transform  

Science Conference Proceedings (OSTI)

The theory and performance of the adaptive discrete cosine transform filter is examined. The discrete cosine transform filter is a realization of an FIR filter as the cascade of an all-zero FIR filter with a bank of IIR digital resonators. Each bank ... Keywords: FIR filter, IIR digital resonators, LMS algorithm, adaptive discrete cosine transform filter, adaptive filters, all-zero FIR filter, filter coefficient, frequency, magnitude, phase, transfer function, update method

S. J. Bukowinski; L. Gerhardt; M. Fargues; G. Coutu

1995-10-01T23:59:59.000Z

44

In-situ characterization of free-volume holes in polymer thin films under controlled humidity conditions with an atmospheric positron probe microanalyzer  

Science Conference Proceedings (OSTI)

A pulsed, slow positron beam, with a diameter of 200 {mu}m, was extracted into air through a thin SiN window of an atmospheric positron probe microanalyzer (PPMA), and used to measure the ortho-positronium lifetimes {tau} in polyvinyl alcohol and polycaprolactam sub-{mu}m-thick films. By measuring the variation of {tau} as a function of relative humidity, the effect of water molecules on the hole sizes, deduced from {tau}, was examined for the films with consideration to the chain mobility. The results demonstrate the usefulness of the atmospheric PPMA to the in-situ characterization of nanoscopic holes in thin films under practical conditions.

Zhou Wei; Oshima, Nagayasu; O'Rourke, Brian E.; Kuroda, Ryunosuke; Suzuki, Ryoichi [Research Institute of Instrumentation Frontier (RIIF), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Chen Zhe; Ito, Kenji [Metrology Institute of Japan (MIJ), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8565 (Japan); Yanagishita, Hiroshi [Research Institute for Innovation in Sustainable Chemistry (ISC), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8565 (Japan); Tsutsui, Takuro; Uedono, Akira [Division of Applied Physics, Faculty of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Hayashizaki, Noriyosu [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Meguro, Tokyo 152-8850 (Japan)

2012-07-02T23:59:59.000Z

45

When Discrete Meets Differential  

Science Conference Proceedings (OSTI)

We provide a theoretical proof showing that under a proportional noise model, the discrete eight point algorithm behaves similarly to the differential eight point algorithm when the motion is small. This implies that the discrete algorithm can handle ... Keywords: Perturbation analysis, Structure from motion

Wen-Yan Lin; Geok-Choo Tan; Loong-Fah Cheong

2010-01-01T23:59:59.000Z

46

Adding Complex Terrain and Stable Atmospheric Condition Capability to the Simulator for On/Offshore Wind Farm Applications (SOWFA) (Presentation)  

DOE Green Energy (OSTI)

This presentation describes changes made to NREL's OpenFOAM-based wind plant aerodynamics solver so that it can compute the stably stratified atmospheric boundary layer and flow over terrain. Background about the flow solver, the Simulator for Off/Onshore Wind Farm Applications (SOWFA) is given, followed by details of the stable stratification/complex terrain modifications to SOWFA, along with some preliminary results calculations of a stable atmospheric boundary layer and flow over a simple set of hills.

Churchfield, M. J.

2013-06-01T23:59:59.000Z

47

Adding Complex Terrain and Stable Atmospheric Condition Capability to the Simulator for On/Offshore Wind Farm Applications (SOWFA) (Presentation)  

SciTech Connect

This presentation describes changes made to NREL's OpenFOAM-based wind plant aerodynamics solver so that it can compute the stably stratified atmospheric boundary layer and flow over terrain. Background about the flow solver, the Simulator for Off/Onshore Wind Farm Applications (SOWFA) is given, followed by details of the stable stratification/complex terrain modifications to SOWFA, along with some preliminary results calculations of a stable atmospheric boundary layer and flow over a simple set of hills.

Churchfield, M. J.

2013-06-01T23:59:59.000Z

48

A Study of the Effect of Molecular and Aerosol Conditions in the Atmosphere on Air Fluorescence Measurements at the Pierre Auger Observatory  

E-Print Network (OSTI)

The air fluorescence detector of the Pierre Auger Observatory is designed to perform calorimetric measurements of extensive air showers created by cosmic rays of above 10^18 eV. To correct these measurements for the effects introduced by atmospheric fluctuations, the Observatory contains a group of monitoring instruments to record atmospheric conditions across the detector site, an area exceeding 3,000 km^2. The atmospheric data are used extensively in the reconstruction of air showers, and are particularly important for the correct determination of shower energies and the depths of shower maxima. This paper contains a summary of the molecular and aerosol conditions measured at the Pierre Auger Observatory since the start of regular operations in 2004, and includes a discussion of the impact of these measurements on air shower reconstructions. Between 10^18 and 10^20 eV, the systematic uncertainties due to all atmospheric effects increase from 4% to 8% in measurements of shower energy, and 4 g/cm^2 to 8 g/cm^...

,

2010-01-01T23:59:59.000Z

49

A discrete fractional random transform  

E-Print Network (OSTI)

We propose a discrete fractional random transform based on a generalization of the discrete fractional Fourier transform with an intrinsic randomness. Such discrete fractional random transform inheres excellent mathematical properties of the fractional Fourier transform along with some fantastic features of its own. As a primary application, the discrete fractional random transform has been used for image encryption and decryption.

Zhengjun Liu; Haifa Zhao; Shutian Liu

2006-05-20T23:59:59.000Z

50

A discrete BGK approximation for strongly degenerate parabolic problems  

E-Print Network (OSTI)

A discrete BGK approximation for strongly degenerate parabolic problems with boundary conditions F strongly degenerate hyperbolic--parabolic equations with initial boundary condition. We prove a priori -- strongly degenerate parabolic equations -- singular perturbation problems -- BGK models 1 Introduction

51

Direct and indirect effects of atmospheric conditions and soil moisture on surface energy partitioning revealed by a prolonged drought at a temperate forest site  

Science Conference Proceedings (OSTI)

The purpose of this paper is to examine the mechanism that controls the variation of surface energy partitioning between latent and sensible heat fluxes at a temperate deciduous forest site in central Missouri, USA. Taking advantage of multiple micrometeorological and ecophysiological measurements and a prolonged drought in the middle of the 2005 growing season at this site, we studied how soil moisture, atmospheric vapor pressure deficit (VPD), and net radiation affected surface energy partitioning. We stratified these factors to minimize potential confounding effects of correlation among them. We found that all three factors had direct effects on surface energy partitioning, but more important, all three factors also had crucial indirect effects. The direct effect of soil moisture was characterized by a rapid decrease in Bowen ratio with increasing soil moisture when the soil was dry and by insensitivity of Bowen ratio to variations in soil moisture when the soil was wet. However, the rate of decrease in Bowen ratio when the soil was dry and the level of soil moisture above which Bowen ratio became insensitive to changes in soil moisture depended on atmospheric conditions. The direct effect of increased net radiation was to increase Bowen ratio. The direct effect of VPD was very nonlinear: Increased VPD decreased Bowen ratio at low VPD but increased Bowen ratio at high VPD. The indirect effects were much more complicated. Reduced soil moisture weakened the influence of VPD but enhanced the influence of net adiation on surface energy partitioning. Soil moisture also controlled how net radiation influenced the relationship between surface energy partitioning and VPD and how VPD affected the relationship between surface energy partitioning and net radiation. Furthermore, both increased VPD and increased net radiation enhanced the sensitivity of Bowen ratio to changes in soil moisture and the effect of drought on surface energy partitioning. The direct and indirect effects of atmospheric conditions and soil moisture on surface energy partitioning identified in this paper provide a target for testing atmospheric general circulation models in their representation of land-atmosphere coupling.

Gu, Lianhong [ORNL; Meyers, T. P. [NOAA ATDD; Pallardy, Stephen G. [University of Missouri; Hanson, Paul J [ORNL; Yang, Bai [ORNL; Heuer, Mark [ATDD, NOAA; Hosman, K. P. [University of Missouri; Riggs, Jeffery S [ORNL; Sluss, Daniel Wayne [ORNL; Wullschleger, Stan D [ORNL

2006-01-01T23:59:59.000Z

52

Pathways Relating Soil Moisture Conditions to Future Summer Rainfall within a Model of the Land–Atmosphere System  

Science Conference Proceedings (OSTI)

In this paper, the key pathways and mechanisms through which soil moisture conditions affect future rainfall over the U.S. Midwest are investigated using a regional climate model. A series of numerical experiments are performed to identify these ...

Jeremy S. Pal; Elfatih A. B. Eltahir

2001-03-01T23:59:59.000Z

53

Neutrino Mass and Mixing with Discrete Symmetry  

E-Print Network (OSTI)

This is a review article about neutrino mass and mixing and flavour model building strategies based on discrete family symmetry. After a pedagogical introduction and overview of the whole of neutrino physics, we focus on the PMNS mixing matrix and the latest global fits following the Daya Bay and RENO experiments which measure the reactor angle. We then describe the simple bimaximal, tri-bimaximal and golden ratio patterns of lepton mixing and the deviations required for a non-zero reactor angle, with solar or atmospheric mixing sum rules resulting from charged lepton corrections or residual trimaximal mixing. The different types of see-saw mechanism are then reviewed as well as the sequential dominance mechanism. We then give a mini-review of finite group theory, which may be used as a discrete family symmetry broken by flavons either completely, or with different subgroups preserved in the neutrino and charged lepton sectors. These two approaches are then reviewed in detail in separate chapters including mechanisms for flavon vacuum alignment and different model building strategies that have been proposed to generate the reactor angle. We then briefly review grand unified theories (GUTs) and how they may be combined with discrete family symmetry to describe all quark and lepton masses and mixing. Finally we discuss three model examples which combine an SU(5) GUT with the discrete family symmetries A4, S4 and Delta(96).

Stephen F. King; Christoph Luhn

2013-01-07T23:59:59.000Z

54

On the solutions of generalized discrete Poisson equation  

E-Print Network (OSTI)

The set of common numerical and analytical problems is introduced in the form of the generalized multidimensional discrete Poisson equation. It is shown that its solutions with square-summable discrete derivatives are unique up to a constant. The proof uses the Fourier transform as the main tool. The necessary condition for the existence of the solution is provided.

Roman Werpachowski

2007-06-19T23:59:59.000Z

55

The Dynamical Discrete Web  

E-Print Network (OSTI)

The dynamical discrete web (DDW), introduced in recent work of Howitt and Warren, is a system of coalescing simple symmetric one-dimensional random walks which evolve in an extra continuous dynamical parameter s. The evolution is by independent updating of the underlying Bernoulli variables indexed by discrete space-time that define the discrete web at any fixed s. In this paper, we study the existence of exceptional (random) values of s where the paths of the web do not behave like usual random walks and the Hausdorff dimension of the set of such exceptional s. Our results are motivated by those about exceptional times for dynamical percolation in high dimension by H\\"aggstrom, Peres and Steif, and in dimension two by Schramm and Steif. The exceptional behavior of the walks in DDW is rather different from the situation for dynamical random walks of Benjamini, H\\"aggstrom, Peres and Steif. In particular, we prove that there are exceptional values of s for which the walk from the origin S^s(n) has limsup S^s(n)/\\sqrt n \\leq K with a nontrivial dependence of the Hausdorff dimension on K. We also discuss how these and other results extend to the dynamical Brownian web, a natural scaling limit of DDW. The scaling limit is the focus of a paper in preparation; it was studied by Howitt and Warren and is related to the Brownian net of Sun and Swart.

L. R. G. Fontes; C. M. Newman; K. Ravishankar; E. Schertzer

2007-04-20T23:59:59.000Z

56

Atmospheric Aerosols  

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

measuring equipment Atmospheric Aerosols Atmospheric aerosol research at Berkeley Lab seeks to understand the air quality and climate impacts of particles in the atmosphere. On...

57

ASSESSMENT OF 90SR AND 137CS PENETRATION INTO REINFORCED CONCRETE (EXTENT OF 'DEEPENING') UNDER NATURAL ATMOSPHERIC CONDITIONS  

SciTech Connect

When assessing the feasibility of remediation following the detonation of a radiological dispersion device or improvised nuclear device in a large city, several issues should be considered including the levels and characteristics of the radioactive contamination, the availability of resources required for decontamination, and the planned future use of the city's structures and buildings. Currently, little is known about radionuclide penetration into construction materials in an urban environment. Knowledge in this area would be useful when considering costs of a thorough decontamination of buildings, artificial structures, and roads in an affected urban environment. Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident in April 1986, may provide some answers. The main objective of this study was to assess the depth of {sup 90}Sr and {sup 137}Cs penetration into reinforced concrete structures in a highly contaminated urban environment under natural weather conditions. Thirteen reinforced concrete core samples were obtained from external surfaces of a contaminated building in Pripyat. The concrete cores were drilled to obtain sample layers of 0-5, 5-10, 10-15, 15-20, 20-30, 30-40, and 40-50 mm. Both {sup 90}Sr and {sup 137}Cs were detected in the entire 0-50 mm profile of the reinforced cores sampled. In most of the cores, over 90% of the total {sup 137}Cs inventory and 70% of the total {sup 90}Sr inventory was found in the first 0-5 mm layer of the reinforced concrete. {sup 90}Sr had penetrated markedly deeper into the reinforced concrete structures than {sup 137}Cs.

Farfan, E.; Jannik, T.

2011-10-01T23:59:59.000Z

58

Thermodynamics of discrete quantum processes  

E-Print Network (OSTI)

We define thermodynamic configurations and identify two primitives of discrete quantum processes between configurations for which heat and work can be defined in a natural way. This allows us to uncover a general second law for any discrete trajectory that consists of a sequence of these primitives, linking both equilibrium and non-equilibrium configurations. Moreover, in the limit of a discrete trajectory that passes through an infinite number of configurations, i.e. in the reversible limit, we recover the saturation of the second law. Finally, we show that for a discrete Carnot cycle operating between four configurations one recovers Carnot's thermal efficiency.

Janet Anders; Vittorio Giovannetti

2012-11-01T23:59:59.000Z

59

Test Map and Discreteness Criteria for Subgroups in PU(1,n;C)  

E-Print Network (OSTI)

We study the discreteness for non-elementary subgroup G in PU(1, n;C), under the assumption that G satisfies Condition A. Mainly, we present that one can use a test map, which need not to be in G, to examine the discreteness of G, and also show that G is discrete, if every two-loxodromic-generator subgroup of G is discrete.

Li, ChangJun

2011-01-01T23:59:59.000Z

60

Trace Anomaly in Geometric Discretization  

E-Print Network (OSTI)

I develop the simplest geometric-discretized analogue of two dimensional scalar field theory, which qualitatively reproduces the trace anomaly of the continuous theory. The discrete analogue provides an interpretation of the trace anomaly in terms of a non-trivial transformation of electric-magnetic duality-invariant modes of resistor networks that accommodate both electric and magnetic charge currents.

Czech, B

2007-01-01T23:59:59.000Z

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


61

Graph-Theoretic Analysis of Discrete-Phase-Space States for ...  

Graph-Theoretic Analysis of Discrete-Phase-Space States for ... Data collected from devices and human condition may be used to forewarn of critical events such as

62

Atmospheric optical calibration system  

DOE Patents (OSTI)

An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions.

Hulstrom, Roland L. (Bloomfield, CO); Cannon, Theodore W. (Golden, CO)

1988-01-01T23:59:59.000Z

63

Atmospheric optical calibration system  

DOE Patents (OSTI)

An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions. 7 figs.

Hulstrom, R.L.; Cannon, T.W.

1988-10-25T23:59:59.000Z

64

Discrete generalized multigroup theory and applications  

E-Print Network (OSTI)

This study develops a fundamentally new discrete generalized multigroup energy expansion theory for the linear Boltzmann transport equation. Discrete orthogonal polynomials are used, in conjunction with the traditional ...

Zhu, Lei, Ph. D. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

65

Atmospheric Aerosols  

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

Tom Kirchstetter with aerosol measurement instrument Atmospheric Aerosols Atmospheric aerosol research at LBNL seeks to understand the air quality and climate impacts of particles...

66

Neutrino Mass and Mixing with Discrete Symmetry  

E-Print Network (OSTI)

This is a review article about neutrino mass and mixing and flavour model building strategies based on discrete family symmetry. After a pedagogical introduction and overview of the whole of neutrino physics, we focus on the PMNS mixing matrix and the latest global fits following the Daya Bay and RENO experiments which measure the reactor angle. We then describe the simple bimaximal, tri-bimaximal and golden ratio patterns of lepton mixing and the deviations required for a non-zero reactor angle, with solar or atmospheric mixing sum rules resulting from charged lepton corrections or residual trimaximal mixing. The different types of seesaw mechanism are then reviewed as well as the sequential dominance mechanism. We then give a mini-review of finite group theory, which may be used as a discrete family symmetry broken by flavons either completely, or with different subgroups preserved in the neutrino and charged lepton sectors. These two approaches are then reviewed in detail in separate chapters including mec...

King, Stephen F

2013-01-01T23:59:59.000Z

67

An Energetics Study of Wintertime Northern Hemisphere Storm Tracks under 4 × CO2 Conditions in Two Ocean–Atmosphere Coupled Models  

Science Conference Proceedings (OSTI)

Different possible behaviors of winter Northern Hemisphere storm tracks under 4 × CO2 forcing are considered by analyzing the response of two of the ocean–atmosphere coupled models that were run for the fourth Assessment Report of the ...

Alexandre Laîné; Masa Kageyama; David Salas-Mélia; Gilles Ramstein; Serge Planton; Sébastien Denvil; Sophie Tyteca

2009-02-01T23:59:59.000Z

68

A Multiscale Nonhydrostatic Atmospheric Model Using Centroidal Voronoi Tesselations and C-Grid Staggering  

Science Conference Proceedings (OSTI)

The formulation of a fully compressible nonhydrostatic atmospheric model called the Model for Prediction Across Scales–Atmosphere (MPAS-A) is described. The solver is discretized using centroidal Voronoi meshes and a C-grid staggering of the ...

William C. Skamarock; Joseph B. Klemp; Michael G. Duda; Laura D. Fowler; Sang-Hun Park; Todd D. Ringler

2012-09-01T23:59:59.000Z

69

Discrete Breathers in Deformed Graphene  

E-Print Network (OSTI)

The linear and nonlinear dynamics of elastically deformed graphene have been studied. The region of the stability of a planar graphene sheet has been represented in the space of the two-dimensional strain (? xx, ? yy) with the x and y axes oriented in the zigzag and armchair directions, respectively. It has been shown that the gap in the phonon spectrum appears in graphene under uniaxial deformation in the zigzag or armchair direction, while the gap is not formed under a hydrostatic load. It has been found that graphene deformed uniaxially in the zigzag direction supports the existence of spatially localized nonlinear modes in the form of discrete breathers, the frequency of which decreases with an increase in the amplitude. This indicates soft nonlinearity in the system. It is unusual that discrete breather has frequency within the phonon spectrum of graphene. This is explained by the fact that the oscillation of the discrete breather is polarized in the plane of the graphene sheet, while the phonon spectral band where the discrete breather frequency is located contains phonons oscillating out of plane. The stability of the discrete breather with respect to the small out-of-plane perturbation of the graphene sheet has been demonstrated. DOI: 10.1134/S0021364011190106 1.

unknown authors

2011-01-01T23:59:59.000Z

70

Nonhydrostatic Atmospheric Modeling Using a Combined Cartesian Grid  

Science Conference Proceedings (OSTI)

A new method for representing topography on a Cartesian grid is applied to a two-dimensional nonhydrostatic atmospheric model to achieve highly precise simulations over steep terrain. The shaved cell method based on finite-volume discretization ...

Hiroe Yamazaki; Takehiko Satomura

2010-10-01T23:59:59.000Z

71

Quantum chaos on discrete graphs  

E-Print Network (OSTI)

Adapting a method developed for the study of quantum chaos on {\\it quantum (metric)} graphs \\cite {KS}, spectral $\\zeta$ functions and trace formulae for {\\it discrete} Laplacians on graphs are derived. This is achieved by expressing the spectral secular equation in terms of the periodic orbits of the graph, and obtaining functions which belongs to the class of $\\zeta$ functions proposed originally by Ihara \\cite {Ihara}, and expanded by subsequent authors \\cite {Stark,Sunada}. Finally, a model of "classical dynamics" on the discrete graph is proposed. It is analogous to the corresponding classical dynamics derived for quantum graphs \\cite {KS}.

Uzy Smilansky

2007-04-26T23:59:59.000Z

72

Retrieval of Atmospheric Optical Depth Profiles from Downward-Looking High-Resolution O2 A-Band Measurements: Optically Thin Conditions  

Science Conference Proceedings (OSTI)

A quasi-linear retrieval was developed to profile moderately thin atmospheres using a high-resolution O2 A-band spectrometer. The retrieval is explicitly linear with respect to single scattering; the multiple-scattering contribution is treated as ...

Qilong Min; Lee C. Harrison

2004-10-01T23:59:59.000Z

73

Atmospheric attenuation of solar radiation  

DOE Green Energy (OSTI)

The attenuation of solar radiation by the atmosphere between the heliostat and receiver of a Central Receiver solar energy system has been computed for a number of atmospheric conditions and tower-heliostat distances. The most important atmospheric variable is found to be the atmospheric aerosol content. No dependence of atmospheric water vapor is found and only a weak dependence on solar zenith angle. For a 500 m heliostat-tower distance two to four percent reductions are expected under typical desert conditions (50 to 120 km visibility). The reduction is approximately linear with heliostat-tower distance. A representative value of the attenuation coefficient is 0.051 km/sup -1/.

Randall, C.M.

1977-05-18T23:59:59.000Z

74

The discrete versus continuous controversy in physics  

Science Conference Proceedings (OSTI)

This paper presents a sample of the deep and multiple interplay between discrete and continuous behaviours and the corresponding modellings in physics. The aim of this overview is to show that discrete and continuous features coexist in any natural phenomenon, ...

Annick Lesne

2007-04-01T23:59:59.000Z

75

Discrete space-time symmetries  

SciTech Connect

Symmetries have always fascinated human beings; they are found in nature, art, and architecture. Physicists, like other scientists have often used symmetries as a basis of their understanding of nature. When the dynamics is unknown, symmetries serve to delineate and define it. When the dynamics is known, symmetries are used to study structure. These two lectures review the theory and present understanding and status of two discrete space-time symmetries,, namely parity (P) and time reversal (T).

Henley, E.M.

1992-12-31T23:59:59.000Z

76

Discrete space-time symmetries  

SciTech Connect

Symmetries have always fascinated human beings; they are found in nature, art, and architecture. Physicists, like other scientists have often used symmetries as a basis of their understanding of nature. When the dynamics is unknown, symmetries serve to delineate and define it. When the dynamics is known, symmetries are used to study structure. These two lectures review the theory and present understanding and status of two discrete space-time symmetries,, namely parity (P) and time reversal (T).

Henley, E.M.

1992-01-01T23:59:59.000Z

77

Locally exact modifications of discrete gradient schemes  

E-Print Network (OSTI)

Locally exact integrators preserve linearization of the original system at every point. We construct energy-preserving locally exact discrete gradient schemes for arbitrary multidimensional canonical Hamiltonian systems by modifying classical discrete gradient schemes. Modifications of this kind are found for any discrete gradient.

Cie?li?ski, Jan L

2013-01-01T23:59:59.000Z

78

Discrete conformal mappings via circle patterns  

Science Conference Proceedings (OSTI)

We introduce a novel method for the construction of discrete conformal mappings from surface meshes of arbitrary topology to the plane. Our approach is based on circle patterns, that is, arrangements of circles---one for each face---with prescribed ... Keywords: Conformal parameterizations, circle patterns, discrete analytic functions, discrete differential geometry, meshing, texture mapping

Liliya Kharevych; Boris Springborn; Peter Schröder

2006-04-01T23:59:59.000Z

79

New mechanism for the formation of discrete stripes in the solar radio spectrum  

SciTech Connect

Dispersion relations are derived for the eigenfrequency spectrum of a spatially periodic nonlinear plasma resonators created in the solar atmosphere due to the development of thermal instability. The eigenfrequency spectra of such resonators are calculated, and it is shown that they are capable of generating tens of discrete stripes (a so-called zebra structure) the number of which is independent of the ratio of the plasma frequency to the gyrofrequency in the source. This may help to overcome all difficulties in explaining the large number of stripes in the zebra structure, as well as the small magnitude of the magnetic field. The spatially periodic plasma resonators under consideration act as a filter with numerous transparency windows separated from one another by opaque regions. The number of stripes and their frequencies in the zebra structure depend on the spatial period of plasma nonuniformity, which is equal to meters or decameters for conditions typical of the solar atmosphere. The high brightness temperature of radio emission in the zebra structure is attributed to coherent emission from a large number of identical small-scale plasma sources. Some regular properties of the observed zebra structure are explained.

Laptukhov, A. I.; Chernov, G. P. [Russian Academy of Sciences, Pushkov Institute of Terrestrial Magnetism, Ionosphere, and Radio-Wave Propagation (Russian Federation)

2006-10-15T23:59:59.000Z

80

A three-level BDDC algorithm for Mortar discretizations  

SciTech Connect

In this paper, a three-level BDDC algorithm is developed for the solutions of large sparse algebraic linear systems arising from the mortar discretization of elliptic boundary value problems. The mortar discretization is considered on geometrically non-conforming subdomain partitions. In two-level BDDC algorithms, the coarse problem needs to be solved exactly. However, its size will increase with the increase of the number of the subdomains. To overcome this limitation, the three-level algorithm solves the coarse problem inexactly while a good rate of convergence is maintained. This is an extension of previous work, the three-level BDDC algorithms for standard finite element discretization. Estimates of the condition numbers are provided for the three-level BDDC method and numerical experiments are also discussed.

Kim, H.; Tu, X.

2007-12-09T23:59:59.000Z

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


81

The Estimation of Wind-Wave Generation in a Discrete Spectral Model  

Science Conference Proceedings (OSTI)

The estimation of wind-wave generation using a new discrete spectral model is compared to Hasselmann et al.'s (1976) parametric model and to models driven primarily by direct transfer of energy from the atmosphere into the surface waves. The main ...

Donald T. Resio

1981-04-01T23:59:59.000Z

82

Contrasting Conditions of Surface Water Balance in Wet Years and Dry Years as a Possible Land Surface-Atmosphere Feedback Mechanism in the West African Sahel  

Science Conference Proceedings (OSTI)

The climate of West Africa, in particular the Sahel, is characterized by multiyear persistence of anomalously wet or dry conditions. Its Southern Hemisphere counterpart, the Kalahari, lacks the persistence that is evident in the Sahel even though ...

A. R. Lare; S. E. Nicholson

1994-05-01T23:59:59.000Z

83

Discrete symmetries and neutrino masses  

SciTech Connect

We constructed a model of neutrino masses using Froggatt-Nielsen mechanism with U(1)xZ{sub 3}xZ{sub 2} flavor symmetry. The model predicts that (2/3)m{sub 2}/m{sub 3}{approx}{radical}(2)sin{theta}{sub 13} at lepton number violating scale M{sub 1}. It is shown that the small values for m{sub 2}/m{sub 3} and sin{theta}{sub 13} are consequences of breaking discrete symmetries.

Siyeon, Kim [Department of Physics, Chung-Ang University, Seoul 156-756 (Korea, Republic of)

2005-02-01T23:59:59.000Z

84

Discreteness of spectrum and positivity criteria for Schrödinger operators  

E-Print Network (OSTI)

We provide a class of necessary and sufficient conditions for the discreteness of spectrum of Schr\\"odinger operators with scalar potentials which are semibounded below. The classical discreteness of spectrum criterion by A.M.Molchanov (1953) uses a notion of negligible set in a cube as a set whose Wiener's capacity is less than a small constant times the capacity of the cube. We prove that this constant can be taken arbitrarily between 0 and 1. This solves a problem formulated by I.M.Gelfand in 1953. Moreover, we extend the notion of negligibility by allowing the constant to depend on the size of the cube. We give a complete description of all negligibility conditions of this kind. The a priori equivalence of our conditions involving different negligibility classes is a non-trivial property of the capacity. We also establish similar strict positivity criteria for the Schr\\"odinger operators with non-negative potentials.

Vladimir Maz'ya; Mikhail Shubin

2003-05-19T23:59:59.000Z

85

Final Report for DOE grant DE-FG02-07ER64432 "New Grid and Discretization Technologies for Ocean and Ice Simulations"  

SciTech Connect

The work reported is in pursuit of these goals: high-quality unstructured, non-uniform Voronoi and Delaunay grids; improved finite element and finite volume discretization schemes; and improved finite element and finite volume discretization schemes. These are sought for application to spherical and three-dimensional applications suitable for ocean, atmosphere, ice-sheet, and other climate modeling applications.

Max Gunzburger

2013-03-12T23:59:59.000Z

86

Generalized Adjoint for Physical Processes with Parameterized Discontinuities. Part IV: Problems in Time Discretization  

Science Conference Proceedings (OSTI)

It is shown analytically and graphically that when parameterized on/off switches are triggered at discrete time levels by a threshold condition in a numerical model, the model solution is not continuously dependent on the initial state. ...

Qin Xu

1997-12-01T23:59:59.000Z

87

AMIP: The Atmospheric Model Intercomparison Project  

Science Conference Proceedings (OSTI)

The Atmospheric Model Intercomparison Project (AMIP) is an international effort to determine the systematic climate errors of atmospheric models under realistic conditions, and calls for the simulation of the climate of the decade 1979–1988 using ...

W. Lawrence Gates

1992-12-01T23:59:59.000Z

88

Synoptic Reorganization of Atmospheric Flow during the Last Glacial Maximum  

Science Conference Proceedings (OSTI)

A coupled global atmosphere–ocean model of intermediate complexity is used to study the influence of glacial boundary conditions on the atmospheric circulation during the Last Glacial Maximum in a systematical manner. A web of atmospheric ...

Flávio Justino; Axel Timmermann; Ute Merkel; Enio P. Souza

2005-08-01T23:59:59.000Z

89

Bell's Jump Process in Discrete Time  

E-Print Network (OSTI)

The jump process introduced by J. S. Bell in 1986, for defining a quantum field theory without observers, presupposes that space is discrete whereas time is continuous. In this letter, our interest is to find an analogous process in discrete time. We argue that a genuine analog does not exist, but provide examples of processes in discrete time that could be used as a replacement.

Jonathan Barrett; Matthew Leifer; Roderich Tumulka

2005-06-08T23:59:59.000Z

90

Discrete Frontal Propagation in a Nonconvective Environment  

Science Conference Proceedings (OSTI)

Surface discrete frontal propagation in a wintertime, nonconvective environment is documented using conventional surface and upper-air data and simulated using the PSU–NCAR mesoscale model.

Joseph J. Charney; J. Michael Fritsch

1999-09-01T23:59:59.000Z

91

NETL: Discrete Fracture Reservoir Simulation Software  

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

Discrete Fracture Reservoir Simulation FRACGENNFFLOW Shale Gas Flow Simulation Shale Gas Flow Simulation FRACGENNFFLOW, a fractured reservoir modeling software developed by the...

92

Recoverable Robust Knapsack: the Discrete Scenario Case  

E-Print Network (OSTI)

Feb 24, 2011... different customers according to their demands maximizing the profit of ... In this paper, we show that for a fixed number of discrete scenarios ...

93

Bayesian Analysis of Discrete Longitudinal Data.  

E-Print Network (OSTI)

??This thesis explores a Bayesian hierarchical model to compare treatment effectiveness for menopausal symptom relief. Specifically, this model recognizes the discrete nature of the data,… (more)

Bernini, Nicholas

2006-01-01T23:59:59.000Z

94

Discrete Thermodynamics of Chemical Equilibria  

E-Print Network (OSTI)

The paper sets forth comprehensive basics of Discrete Thermodynamics of Chemical Equilibria (DTD), developed by the author during the last decade and spread over series of publications. Based on the linear equations of irreversible thermodynamics, De Donder's definition of the thermodynamic force, and the Le Chatelier principle, DTD brings forward a notion of chemical equilibrium as a balance of internal and external thermodynamic forces, acting against a chemical system. The basic expression of DTD is a logistic map that ties together energetic characteristics of the chemical transformation in the system, its deviation from true thermodynamic equilibrium, and the sum of thermodynamic forces, causing that deviation. System deviation from thermodynamic equilibrium is the major variable of the theory. Solutions to the basic map define the chemical system domain of states comprising bifurcation diagrams with four areas, from true thermodynamic equilibrium to chaos, having specific distinctive meaning for chemica...

Zilbergleyt, B

2008-01-01T23:59:59.000Z

95

Discrete particle transport in porous media : discrete observations of physical mechanisms influencing particle behavior  

E-Print Network (OSTI)

An understanding of how discrete particles in the micron to submicron range behave in porous media is important to a number of environmental problems. Discrete particle behavior in the interior of a porous medium is complex ...

Yoon, Joon Sik, 1973-

2005-01-01T23:59:59.000Z

96

Precursors to atmospheric blocking events  

E-Print Network (OSTI)

Atmospheric blocking events disturb synoptic-scale features from their normal eastward progression, causing anomalous weather conditions for the duration of the blocking event. The essence of blocking can be captured by ...

Marino, Garrett P

2009-01-01T23:59:59.000Z

97

Super Gabor frames on discrete periodic sets  

Science Conference Proceedings (OSTI)

Due to its potential applications in multiplexing techniques such as time division multiple access and frequency division multiple access, superframe has interested some mathematicians and engineering specialists. In this paper, we investigate super ... Keywords: 42C40, Discrete Zak transform, Discrete periodic sets, Gabor dual, Super Gabor frame, Superframe

Yun-Zhang Li; Qiao-Fang Lian

2013-05-01T23:59:59.000Z

98

Structural Workshop Paper---Estimating Discrete Games  

Science Conference Proceedings (OSTI)

This paper provides a critical review of the methods for estimating static discrete games and their relevance for quantitative marketing. We discuss the various modeling approaches, alternative assumptions, and relevant trade-offs involved in taking ... Keywords: discrete choice, games estimation, structural models

Paul B. Ellickson; Sanjog Misra

2011-11-01T23:59:59.000Z

99

Discrete-event modelling of fire spreading  

Science Conference Proceedings (OSTI)

We deal here with the application of discrete-event System Specification (DEVS) formalism to implement a semi-physical fire spread model. Currently, models from physics finely representing forest fires are not efficient and still under development. If ... Keywords: Cellular models, DEVS, Discrete-event modelling and simulation, Fire spread

Alexandre Muzy; Eric Innocenti; Antoine Aiello; Jean-François Santucci; Thierry Marcelli; Paul Antoine Santoni

2008-02-01T23:59:59.000Z

100

Black Hole Spectrum: Continuous or Discrete?  

E-Print Network (OSTI)

We formulate a qualitative argument, based on Heisenberg's uncertainty principle, to support the claim that when the effects of matter fields are assumed to overshadow the effects of quantum mechanics of spacetime, the discrete spectrum of black hole radiation, as such as predicted by Bekenstein's proposal for a discrete black hole area spectrum, reduces to Hawking's black-body spectrum.

Jarmo Makela

1996-08-30T23:59:59.000Z

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


101

MULTISCALE DISCRETIZATION OF SHAPE CONTOURS  

SciTech Connect

We present an efficient multi-scale scheme to adaptively approximate the continuous (or densely sampled) contour of a planar shape at varying resolutions. The notion of shape is intimately related to the notion of contour, and the efficient representation of the contour of a shape is vital to a computational understanding of the shape. Any polygonal approximation of a planar smooth curve is equivalent to a piecewise constant approximation of the parameterized X and Y coordinate functions of a discrete point set obtained by densely sampling the curve. Using the Haar wavelet transform for the piecewise approximation yields a hierarchical scheme in which the size of the approximating point set is traded off against the morphological accuracy of the approximation. Our algorithm compresses the representation of the initial shape contour to a sparse sequence of points in the plane defining the vertices of the shape's polygonal approximation. Furthermore, it is possible to control the overall resolution of the approximation by a single, scale-independent parameter.

Prasad, L.; Rao, R.

2000-09-01T23:59:59.000Z

102

Modeling the Atmospheric General Circulation Using a Spherical Geodesic Grid: A New Class of Dynamical Cores  

Science Conference Proceedings (OSTI)

This paper documents the development and testing of a new type of atmospheric dynamical core. The model solves the vorticity and divergence equations in place of the momentum equation. The model is discretized in the horizontal using a geodesic ...

Todd D. Ringler; Ross P. Heikes; David A. Randall

2000-07-01T23:59:59.000Z

103

Adaptive Grid Refinement for Two-Dimensional and Three-Dimensional Nonhydrostatic Atmospheric Flow  

Science Conference Proceedings (OSTI)

Although atmospheric phenomena tend to be localized in both time and space, numerical models generally employ only uniform discretizations or fixed nested grids. An adaptive grid technique implemented in 2D and 3D nonhydrostatic elastic ...

William C. Skamarock; Joseph B. Klemp

1993-03-01T23:59:59.000Z

104

Two-Dimensional Radiative Transfer in Cloudy Atmospheres: The Spherical Harmonic Spatial Grid Method  

Science Conference Proceedings (OSTI)

A new two-dimensional monochromatic method that computes the transfer of solar or thermal radiation through atmospheres with arbitrary optical properties is described. The model discretizes the radiative transfer equation by expanding the angular ...

K. Franklin Evans

1993-09-01T23:59:59.000Z

105

Brief paper: Output feedback strict passivity of discrete-time nonlinear systems and adaptive control system design with a PFC  

Science Conference Proceedings (OSTI)

In this paper, a passivity-based adaptive output feedback control for discrete-time nonlinear systems is considered. Output Feedback Strictly Passive (OFSP) conditions in order to design a stable adaptive output control system will be established. Further, ... Keywords: Adaptive control, Discrete nonlinear systems, Output feedback, Parallel feedforward compensator, Strict passivity

Ikuro Mizumoto; Satoshi Ohdaira; Zenta Iwai

2010-09-01T23:59:59.000Z

106

On the parallelization of the acoustic wave equation with absorbing boundary conditions  

SciTech Connect

Many practical problems involve wave propagation through atmosphere, oceans, or terrestrial crust. Modeling and analysis of these problems is usually done in (semi)infinite domains, but numerical calculations obviously impose restriction to finite domains. To mimic the actual behavior in the (semi)infinite medium, artificial absorbing boundary conditions are imposed at the boundaries, whereby waves can only exit, but not enter the finite computational domain. Efficient absorbing boundary conditions are difficult to analyze and costly to run. In particular, it is of interest to assess whether the wave equation with (approximate or exact) absorbing boundary conditions admits a suitable diagonalization. This would open the possibility for parallelizing many important numerical codes used in applications. In this paper the authors propose a set of stable, local, absorbing boundary conditions for the discrete acoustic wave equation. They show that the acoustic wave equation with absorbing boundary conditions cannot be exactly diagonalized.

White, C.T. [California Inst. of Tech., Pasadena, CA (United States). Dept. of Mathematics; Protopopescu, V.A.; Barhen, J. [Oak Ridge National Lab., TN (United States). Center for Engineering Systems Advanced Research

1998-07-01T23:59:59.000Z

107

A discrete curvature on a planar graph  

E-Print Network (OSTI)

Given a planar graph derived from a spherical, euclidean or hyperbolic tessellation, one can define a discrete curvature by combinatorial properties, which after embedding the graph in a compact 2d-manifold, becomes the Gaussian curvature.

M. Lorente

2004-12-20T23:59:59.000Z

108

Combining sustainability criteria with discrete event simulation  

Science Conference Proceedings (OSTI)

This paper attempts to highlight shortcomings in the concept of sustainability and ways to make the concept more workable by presenting the development of an Environmental Management Information System (EMIS) as a combination of discrete event simulation ...

Andi H. Widok; Volker Wohlgemuth; Bernd Page

2011-12-01T23:59:59.000Z

109

A discrete model of thin shells  

Science Conference Proceedings (OSTI)

We present a discrete model for the behavior of thin flexible structures, such as hats, leaves, and aluminum cans, which are characterized by a curved undeformed configuration. Previously such models required complex continuum mechanics formulations ...

Eitan Grinspun

2005-07-01T23:59:59.000Z

110

Quantum Gravity Phenomenology, Lorentz Invariance and Discreteness  

E-Print Network (OSTI)

Contrary to what is often stated, a fundamental spacetime discreteness need not contradict Lorentz invariance. A causal set's discreteness is in fact locally Lorentz invariant, and we recall the reasons why. For illustration, we introduce a phenomenological model of massive particles propagating in a Minkowski spacetime which arises from an underlying causal set. The particles undergo a Lorentz invariant diffusion in phase space, and we speculate on whether this could have any bearing on the origin of high energy cosmic rays.

Fay Dowker; Joe Henson; Rafael D. Sorkin

2003-11-17T23:59:59.000Z

111

Fire emergency evacuation simulation based on integrated fire-evacuation model with discrete design method  

Science Conference Proceedings (OSTI)

Emergency evacuation under fire condition in a mass transit station is a great concern especially in developing countries. The interaction between fire and human is very important in the analysis of emergency evacuation under fire condition. An integrated ... Keywords: Discrete design method, Emergency evacuation, FDS+Evac, Fire-evacuation model, Total evacuation time, Waiting time

Peizhong Yang, Chao Li, Dehu Chen

2013-11-01T23:59:59.000Z

112

Discrete gravity models and Loop Quantum Gravity: a short review  

E-Print Network (OSTI)

We review the relation between loop quantum gravity on a fixed graph and discrete models of gravity. We compare Regge and twisted geometries, and discuss discrete actions based on twisted geometries and on the discretization of the Plebanski action. We discuss the role of discrete geometries in the spin foam formalism, with particular attention to the definition of the simplicity constraints.

Dupuis, Maite; Speziale, Simone

2012-01-01T23:59:59.000Z

113

Energy Levels of "Hydrogen Atom" in Discrete Time Dynamics  

E-Print Network (OSTI)

We analyze dynamical consequences of a conjecture that there exists a fundamental (indivisible) quant of time. In particular we study the problem of discrete energy levels of hydrogen atom. We are able to reconstruct potential which in discrete time formalism leads to energy levels of unperturbed hydrogen atom. We also consider linear energy levels of quantum harmonic oscillator and show how they are produced in the discrete time formalism. More generally, we show that in discrete time formalism finite motion in central potential leads to discrete energy spectrum, the property which is common for quantum mechanical theory. Thus deterministic (but discrete time!) dynamics is compatible with discrete energy levels.

Andrei Khrennikov; Yaroslav Volovich

2006-04-27T23:59:59.000Z

114

Sensitivity of Dynamical Intraseasonal Prediction Skills to Different Initial Conditions  

Science Conference Proceedings (OSTI)

Predictability of intraseasonal oscillation (ISO) relies on both initial conditions and lower boundary conditions (or atmosphere–ocean interaction). The atmospheric reanalysis datasets are commonly used as initial conditions. Here, the biases of ...

Xiouhua Fu; Bin Wang; June-Yi Lee; Wanqiu Wang; Li Gao

2011-08-01T23:59:59.000Z

115

Fast Mix Table Construction for Material Discretization  

Science Conference Proceedings (OSTI)

An effective hybrid Monte Carlo--deterministic implementation typically requires the approximation of a continuous geometry description with a discretized piecewise-constant material field. The inherent geometry discretization error can be reduced somewhat by using material mixing, where multiple materials inside a discrete mesh voxel are homogenized. Material mixing requires the construction of a ``mix table,'' which stores the volume fractions in every mixture so that multiple voxels with similar compositions can reference the same mixture. Mix table construction is a potentially expensive serial operation for large problems with many materials and voxels. We formulate an efficient algorithm to construct a sparse mix table in $O(\\text{number of voxels}\\times \\log \\text{number of mixtures})$ time. The new algorithm is implemented in ADVANTG and used to discretize continuous geometries onto a structured Cartesian grid. When applied to an end-of-life MCNP model of the High Flux Isotope Reactor with 270 distinct materials, the new method improves the material mixing time by a factor of 100 compared to a naive mix table implementation.

Johnson, Seth R [ORNL

2013-01-01T23:59:59.000Z

116

Electroless plating apparatus for discrete microsized particles  

SciTech Connect

Method and apparatus are disclosed for producing very uniform coatings of a desired material on discrete microsized particles by electroless techniques. Agglomeration or bridging of the particles during the deposition process is prevented by imparting a sufficiently random motion to the particles that they are not in contact with each other for a time sufficient for such to occur.

Mayer, Anton (Los Alamos, NM)

1978-01-01T23:59:59.000Z

117

Electrolytic plating apparatus for discrete microsized particles  

SciTech Connect

Method and apparatus are disclosed for electrolytically producing very uniform coatings of a desired material on discrete microsized particles. Agglomeration or bridging of the particles during the deposition process is prevented by imparting a sufficiently random motion to the particles that they are not in contact with a powered cathode for a time sufficient for such to occur.

Mayer, Anton (Los Alamos, NM)

1976-11-30T23:59:59.000Z

118

Time–Space Distribution of Long-Range Atmospheric Predictability  

Science Conference Proceedings (OSTI)

The global three-dimensional structure of long-range (one month to one season) atmospheric predictability was investigated with a general circulation model. The main focus was to ascertain the role of atmospheric initial conditions for such ...

Thomas Reichler; John O. Roads

2004-02-01T23:59:59.000Z

119

Hierarchical Bayesian Approach to Boundary Value Problems with Stochastic Boundary Conditions  

Science Conference Proceedings (OSTI)

Boundary value problems are ubiquitous in the atmospheric and ocean sciences. Typical settings include bounded, partially bounded, global, and limited area domains, discretized for applications of numerical models of the relevant fluid equations. ...

Christopher K. Wikle; L. Mark Berliner; Ralph F. Milliff

2003-06-01T23:59:59.000Z

120

Coastal Atmospheric Circulation around an Idealized Cape during Wind-Driven Upwelling Studied from a Coupled Ocean–Atmosphere Model  

Science Conference Proceedings (OSTI)

The study analyzes atmospheric circulation around an idealized coastal cape during summertime upwelling-favorable wind conditions simulated by a mesoscale coupled ocean–atmosphere model. The domain resembles an eastern ocean boundary with a ...

Natalie Perlin; Eric D. Skyllingstad; Roger M. Samelson

2011-03-01T23:59:59.000Z

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


121

The inverse scattering problem for a discrete Sturm-Liouville equation on the line  

Science Conference Proceedings (OSTI)

This paper investigates the inverse scattering problem for a discrete Sturm-Liouville equation on the entire line with coefficients that stabilize to zero in one direction. We derive a necessary and a sufficient condition on the scattering data so that the inverse problem is uniquely solvable. Bibliography: 23 titles.

Khanmamedov, Agil Kh [Baku State University, Baku (Azerbaijan)

2011-07-31T23:59:59.000Z

122

Optimal control of Cauchy problem for first-order discrete and partial differential inclusions  

Science Conference Proceedings (OSTI)

Optimization of Cauchy problem for discrete inclusions is reduced to problem with geometric constraints in Hilbert space ż2 and necessary and sufficient condition for optimality is derived. Both for convex and non-convex partial differential ... Keywords: 49K20, 49K24, Cauchy problem, Set-valued, approximation, improper integral, locally conjugate

E. N. Mahmudov

2009-10-01T23:59:59.000Z

123

Green's function of a finite chain and the discrete Fourier transform  

E-Print Network (OSTI)

A new expression for the Green's function of a finite one-dimensional lattice with nearest neighbor interaction is derived via discrete Fourier transform. Solution of the Heisenberg spin chain with periodic and open boundary conditions is considered as an example. Comparison to Bethe ansatz clarifies the relation between the two approaches.

S. Cojocaru

2007-04-22T23:59:59.000Z

124

A Step toward Transparent Boundary Conditions for Meteorological Models  

Science Conference Proceedings (OSTI)

Transparent boundary conditions for the linearized shallow water equations are constructed by incorporating the boundary conditions into equations that describe unidirectional waves. The shallow water equations are then discretized using a semi-...

A. McDonald

2002-01-01T23:59:59.000Z

125

Discrete variable theory of triatomic photodissociation  

SciTech Connect

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

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

1983-07-01T23:59:59.000Z

126

Bessel-Zernike Discrete Variable Representation Basis  

SciTech Connect

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

Cerjan, C J

2005-10-24T23:59:59.000Z

127

Discrete mechanics, optimal control and formation flying spacecraft  

E-Print Network (OSTI)

Discrete mechanics, optimal control and formation flying spacecraft Oliver Junge Center-Bl¨obaum partially supported by the CRC 376 Oliver Junge Discrete mechanics, optimal control and formation flying spacecraft p.1 #12;Outline mechanical optimal control problem direct discretization of the variational

Patrick, George

128

Adaptive fuzzy logic control of discrete-time dynamical systems  

Science Conference Proceedings (OSTI)

The objective of this paper is to achieve tracking control of a class of unknown nonlinear dynamical systems using a discrete-time fuzzy logic controller (FLC). Designing a discrete-time FLC is significant because almost all FLCs are implemented on digital ... Keywords: Adaptive control, Discrete-time control, Fuzzy approximation, Fuzzy logic, Universal fuzzy controller

S. Jagannathan; M. W. Vandegrift; F. L. Lewis

2000-02-01T23:59:59.000Z

129

Spectral Preconditioners for Nonhydrostatic Atmospheric Models  

Science Conference Proceedings (OSTI)

The elliptic problems in semi-implicit nonhydrostatic atmospheric models are difficult. Typically, they are poorly conditioned, nonseparable, contain cross-derivative terms, and are often nonsymmetric. Here, the resulting linear system is solved ...

Stephen J. Thomas; Joshua P. Hacker; Piotr K. Smolarkiewicz; Roland B. Stull

2003-10-01T23:59:59.000Z

130

Intraseasonal Variability in a Dry Atmospheric Model  

Science Conference Proceedings (OSTI)

A long integration of a primitive equation dry atmospheric model with time-independent forcing under boreal winter conditions is analyzed. A variety of techniques such as time filtering, space–time spectral analysis, and lag regressions are used ...

Hai Lin; Gilbert Brunet; Jacques Derome

2007-07-01T23:59:59.000Z

131

Linear Baroclinic Instability in the Martian Atmosphere  

Science Conference Proceedings (OSTI)

The linear baroclinic instability of zonal-mean flows like those in the wintertime Martian atmosphere under both relatively nondusty and highly dusty conditions is examined using a spherical quasi-geostrophic model. The basic states are idealized,...

Jeffrey R. Barnes

1984-05-01T23:59:59.000Z

132

Towards a Number Theoretic Discrete Hilbert Transform  

E-Print Network (OSTI)

This paper presents an approach for the development of a number theoretic discrete Hilbert transform. The forward transformation has been applied by taking the odd reciprocals that occur in the DHT matrix with respect to a power of 2. Specifically, the expression for a 16-point transform is provided and results of a few representative signals are provided. The inverse transform is the inverse of the forward 16-point matrix. But at this time the inverse transform is not identical to the forward transform and, therefore, our proposed number theoretic transform must be taken as a provisional result.

Kandregula, Renuka

2009-01-01T23:59:59.000Z

133

Bilinear control of discrete spectrum Schrödinger operators  

E-Print Network (OSTI)

The bilinear control problem of the Schr\\"odinger equation $i\\frac{\\partial}{\\partial t}\\psi(t)$ $=(A+u(t) B)\\psi(t)$, where $u(t)$ is the control function, is investigated through topological irreducibility of the set $\\mathfrak{M}=\\{e^{-it (A+u B)}, u\\in \\mathbb{R}, t>0\\}$ of bounded operators. This allows to prove the approximate controllability of such systems when the uncontrolled Hamiltonian $A$ has a simple discrete spectrum and under an appropriate assumption on $B$.

Kais Ammari; Zied Ammari

2010-04-30T23:59:59.000Z

134

A Family of Discrete Magnetically Switchable Nanoballs  

Science Conference Proceedings (OSTI)

The thermal and light-induced magnetic properties of a family of discrete magnetically switchable 'nanoball' species (3 nm in diameter) is reported. The self-assembly of these materials is accomplished by the use of the metallo building block, [Cu([Tp{sup 4-py}])(NCCH{sub 3})] ([Tp{sup 4-py}]=tris-[3-(4{prime}-pyridyl)pyrazol-1-yl]hydroborate), combined with a [Fe(NCX){sub 2}] (X = S, Se and BH{sub 3}) species. We previously showed that the thiocyanate analogue (Fe(NCS)-nano) undergoes a thermal and light-induced spin crossover (SCO) - the largest such discrete SCO material reported. Now included in this family are the Se and BH{sub 3} analogues, Fe(NCSe)-nano and Fe(NCBH{sub 3})-nano, which show increased thermal transition temperatures (T{sub 1/2} = 124 K, 162 and 173 K). This variation in transition temperature over the series S < Se < BH{sub 3} results in diverse photomagnetic properties, such that the light-induced excited spin state trapping (LIESST) effect is exhibited to varying degrees and at different temperatures by the S, Se and BH{sub 3} analogues.

Duriska, Martin B.; Neville, Suzanne M.; Moubaraki, Boujemaa; Murray, Keith S.; Balde, Chérif; Létard, Jean-François; Kepert, Cameron J.; Batten, Stuart R. (Sydney); (Monash); (CNRS-LSP)

2012-08-20T23:59:59.000Z

135

The Boulder Atmospheric Observatory  

Science Conference Proceedings (OSTI)

The Boulder Atmospheric Observatory (BAO) is a unique research facility for studying the planetary boundary layer and for testing and calibrating atmospheric sensors. The facility includes a 300 m tower instrumented with fast- and slow-response ...

J. C. Kaimal; J. E. Gaynor

1983-05-01T23:59:59.000Z

136

Atmospheric Radiation Measurement Program  

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

Atmospheric Observatory (UAO) Pilot Experiment at NYC" - Michael Reynolds, BNL 17:30 "EML Pilot Studies for the Urban Atmospheric Observatory" - Hsi-Na (Sam) Lee, EML 17:40 "A...

137

Adaptive discrete cosine transform for feedback active noise control  

Science Conference Proceedings (OSTI)

The theory and performance of adaptive discrete cosine transform filters for feedback active noise control (ANC) is examined. The discrete cosine transform filter is a realization of an FIR filter as the cascade of an all-zero FIR filter with a bank ... Keywords: FIR filter, IIR digital resonators bank, active noise control, adaptive discrete cosine transform filters, adaptive filter, all-zero FIR filter, discrete cosine transform filter, feedback active noise control, filter-X LMS implementation, frequency, magnitude coefficient, phase coefficient, single error microphone, single loudspeaker, transfer function

G. Coutu; M. Dignan

1995-10-01T23:59:59.000Z

138

Discrete Quantum Spectrum of Observable Correlations from Inflation  

E-Print Network (OSTI)

The decoherence of quantum fluctuations into classical perturbations during inflation is discussed. A simple quantum mechanical argument, using a spatial particle wavefunction rather than a field description, shows that observable correlations from inflation must have a discrete spectrum, since they originate and freeze into the metric within a compact region. The number of discrete modes is estimated using a holographic bound on the number of degrees of freedom. The discreteness may be detectable in some models; for example, if there is a fundamental universal frequency spectrum, the inflationary gravitational wave background may be resolvable into discrete emission lines.

Craig J. Hogan

2005-04-16T23:59:59.000Z

139

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

Science Conference Proceedings (OSTI)

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

2011-01-12T23:59:59.000Z

140

Discrete Element Method Applied to the Vibration Process of Coke ...  

Science Conference Proceedings (OSTI)

In the present work, effects of particle shape and size distribution on vibrated bulk density (VBD) of dry coke samples have been investigated. Discrete Element ...

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


141

Variational estimates using a discrete variable representation  

SciTech Connect

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

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

2004-09-01T23:59:59.000Z

142

Decreasing Isosurface Complexity Via Discrete Fitting  

E-Print Network (OSTI)

Since the introduction of techniques for isosurface extraction from volumetric datasets, one of the hardest problems has been to reduce the number of generated triangles (or polygons). This paper presents an algorithm that considerably reduces the number of triangles generated by a Marching Cubes algorithm, while presenting very close or shorter running times. The algorithm first assumes discretization of the dataset space and replaces cell edge interpolation by midpoint selection. Under these assumptions the extracted surfaces are composed of polygons lying within a finite number of incidences, thus allowing simple merging of the output facets into large coplanar triangular facets. Lastly, the vertices which survived the decimation process are located on their exact positions and normals are computed. An experimental evaluation of the proposed approach on datasets relevant to biomedical imaging and chemical modeling is reported. 2000 Elsevier Science B.V. All rights reserved. Keywords: Volume rendering; Isosurface extraction; Marching cubes; Surface simplification 1.

Claudio Montani; Riccardo Scateni; Roberto Scopigno

2000-01-01T23:59:59.000Z

143

An Evaluation of the Strength of Land–Atmosphere Coupling  

Science Conference Proceedings (OSTI)

Two ensembles of 1-month integrations of a coupled land–atmosphere climate model that differ only in their treatment of land surface boundary conditions have been generated from initial conditions chosen from the July states taken from each year ...

Paul A. Dirmeyer

2001-08-01T23:59:59.000Z

144

Discrete Momentum Mechanics and Faster Than Light Transition  

E-Print Network (OSTI)

In this work a new mechanics will be studied which is based on the hypothesis that the change of linear momentum of a particle happens as a discrete pulses. By using this hypothesis and by considering Newton's relation between energy and momentum, and the law of mass and energy conservation as a priori, the Einstein dispersion relation can be derived as a zero approximation without using Lorentz transformations. Other terms will be derived as a corrections to this relation. It will be shown that the effect of the corrections will be smaller and smaller with the increase of momentum. The work will offer an explanation of why the velocity of light seems to be constant regardless of the velocity of the source, and under which condition this will be changed. Also a prediction is made that faster than light transition could happen theoretically under certain conditions, and a nonzero mass photon can exist in nature. The work is purely classical in the sense that it doesn't involve any uncertainty relations.

Munir Al-Hashimi

2004-12-02T23:59:59.000Z

145

The discrete fractional random cosine and sine transforms  

E-Print Network (OSTI)

Based on the discrete fractional random transform (DFRNT), we present the discrete fractional random cosine and sine transforms (DFRNCT and DFRNST). We demonstrate that the DFRNCT and DFRNST can be regarded as special kinds of DFRNT and thus their mathematical properties are inherited from the DFRNT. Numeral results of DFRNCT and DFRNST for one and two dimensional functions have been given.

Zhengjun Liu; Qing Guo; Shutian Liu

2006-05-22T23:59:59.000Z

146

Discrete Wavelet Transform: Architectures, Design and Performance Issues  

Science Conference Proceedings (OSTI)

Due to the demand for real time wavelet processors in applications such as video compression [1], Internet communications compression [2], object recognition [3], and numerical analysis, many architectures for the Discrete Wavelet Transform (DWT) systems ... Keywords: computer architecture, digital filters, digital signal processors, discrete transforms, wavelet transforms

Michael Weeks; Magdy Bayoumi

2003-09-01T23:59:59.000Z

147

Mixed-hybrid discretization methods for the P1 equations  

Science Conference Proceedings (OSTI)

We consider mixed-hybrid discretization methods for the linear Boltzmann transport equation which is extensively used in computational neutron transport. Mixed-hybrid methods combine attractive features of both mixed and hybrid methods, namely the simultaneous ... Keywords: 02.60.Cb, 02.70.Dh, 65N12, 65N30, Linear Boltzmann transport equation, Mixed-hybrid discretization methods, P1 approximation

S. Van Criekingen; R. Beauwens

2007-02-01T23:59:59.000Z

148

Efficient optimal design of uncertain discrete time dynamical systems  

Science Conference Proceedings (OSTI)

In this paper we consider the problem of optimal design of an uncertain discrete time nonlinear dynamical system. The problem is formulated using an a-posterori design criterion, which can account for uncertainties generated by the dynamics of the system ... Keywords: Discrete time dynamical systems, Optimal design, Randomized algorithms, Uncertain parameters

Chenxi Lin; Thordur Runolfsson

2012-10-01T23:59:59.000Z

149

Discrete element modeling of machine-manure interactions  

Science Conference Proceedings (OSTI)

The discrete element method (DEM) was applied to the study of the machine-product interactions occurring in manure handling and land application equipment. Two types of conveying systems (scraper and 4-auger system) were modeled along with a hopper and ... Keywords: Conveying systems, Discrete element method (DEM), Flow rate, Manure, Numerical modeling, Specific energy, Spreader

H. Landry; C. Laguë; M. Roberge

2006-06-01T23:59:59.000Z

150

Two Classes of Elliptic Discrete Fourier Transforms: Properties and Examples  

Science Conference Proceedings (OSTI)

This paper analyzes the block structure of the matrix of the N-point discrete Fourier transform (DFT) in the real space R 2N . Each block of this matrix corresponds to the Givens transformation, or elementary rotation ... Keywords: Discrete Fourier transform, Fourier analysis, Signal and image processing

Artyom M. Grigoryan

2011-03-01T23:59:59.000Z

151

Partially blind threshold signatures based on discrete logarithm  

Science Conference Proceedings (OSTI)

In this paper, we propose a group-oriented partially blind (t, n) threshold signature scheme based on the discrete logarithm problem. By the scheme, any t out of n signers in a group can represent the group to sign partially blind threshold signatures, ... Keywords: Discrete logarithm, E-cash systems, Partially blind signatures, Privacy and security, Secure, Secure voting schemes, Threshold signatures

W. -S. Juang; C. -L. Lei

1999-01-01T23:59:59.000Z

152

Pricing Discretely Monitored Asian Options by Maturity Randomization  

Science Conference Proceedings (OSTI)

We present a new methodology based on maturity randomization to price discretely monitored arithmetic Asian options when the underlying asset evolves according to a generic Lévy process. Our randomization technique considers the option expiry ... Keywords: Asian option, Lévy process, discrete monitoring, fast Fourier transform, integral equation, option pricing, quadrature formula

Gianluca Fusai; Daniele Marazzina; Marina Marena

2011-01-01T23:59:59.000Z

153

Atmospheric Radiation Measurement Program  

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

3 3 ARM 2003 Tom Ackerman Chief Scientist Tom Ackerman Chief Scientist ARM ARM Atmospheric Radiation Measurement Atmospheric Radiation Measurement WARNING! WARNING! Today is April 1 But that has NO bearing on this message Today is April 1 But that has NO bearing on this message ARM ARM Atmospheric Radiation Measurement Atmospheric Radiation Measurement Two Topics Two Topics * Status of ARM (quick overview) * Science plan - ARM in the next 5 years * Status of ARM (quick overview) * Science plan - ARM in the next 5 years ARM ARM Atmospheric Radiation Measurement Atmospheric Radiation Measurement ARM Status - Science ARM Status - Science * Steadily increasing productivity - Poster session - over 220 posters (may need to do something about submissions next year) - Peer-reviewed articles: 2.5 to 3 per year per

154

Crack Growth in Solid Oxide Fuel Cell Materials: From Discrete to Continuum Damage Modeling  

Science Conference Proceedings (OSTI)

This paper addresses the cracking problem of glass and ceramic materials used in solid oxide fuel cells (SOFCs). Analyses of an internal crack and of an interface crack between dissimilar materials were conducted using a modified boundary layer modeling approach. In this approach, fracture is allowed to occur in a small process window situated at an initial crack tip. Elastic displacement crack-tip fields are prescribed as remote boundary conditions. Crack propagation was first modeled discretely. Next, a continuum damage mechanics (CDM) model for brittle materials was developed to capture damage and crack growth in the process window. In particular, the damage model was applied to a glass-ceramic material that had been developed in-house for sealing purposes. Discrete and continuum damage solutions were then compared. Finally, the CDM model was used to determine the crack propagation direction as a function of a mode mixity measure.

Nguyen, Ba Nghiep; Koeppel, Brian J.; Ahzi, Said; Khaleel, Mohammad A.; Singh, Prabhakar

2006-04-01T23:59:59.000Z

155

Multidimensional electron-photon transport with standard discrete ordinates codes  

Science Conference Proceedings (OSTI)

A method is described for generating electron cross sections that are compatible with standard discrete ordinates codes without modification. There are many advantages of using an established discrete ordinates solver, e.g. immediately available adjoint capability. Coupled electron-photon transport capability is needed for many applications, including the modeling of the response of electronics components to space and man-made radiation environments. The cross sections have been successfully used in the DORT, TWODANT and TORT discrete ordinates codes. The cross sections are shown to provide accurate and efficient solutions to certain multidimensional electronphoton transport problems.

Drumm, C.R.

1995-12-31T23:59:59.000Z

156

The Transmission Property of the Discrete Heisenberg Ferromagnetic Spin Chain  

E-Print Network (OSTI)

We present a mechanism for displaying the transmission property of the discrete Heisenberg ferromagnetic spin chain (DHF) via a geometric approach. By the aid of a discrete nonlinear Schr\\"odinger-like equation which is the discrete gauge equivalent to the DHF, we show that the determination of transmitting coefficients in the transmission problem is always bistable. Thus a definite algorithm and general stochastic algorithms are presented. A new invariant periodic phenomenon of the non-transmitting behavior for the DHF, with a large probability, is revealed by an adoption of various stochastic algorithms.

Qing Ding; Wei Lin

2008-01-14T23:59:59.000Z

157

A Study of the Incoming Longwave Atmospheric Radiation from a Clear Sky  

Science Conference Proceedings (OSTI)

A band model for atmospheric absorption is used to calculate the incoming longwave atmospheric radiative flux for some typical clear sky conditions. The sky radiation is also measured using a specially-designed calorimetric apparatus over a wide ...

J. W. Ramsey; H. D. Chiang; R. J. Goldstein

1982-04-01T23:59:59.000Z

158

Error Structure and Atmospheric Temperature Trends in Observations from the Microwave Sounding Unit  

Science Conference Proceedings (OSTI)

The Microwave Sounding Unit (MSU) onboard the National Oceanic and Atmospheric Administration polar-orbiting satellites measures the atmospheric temperature from the surface to the lower stratosphere under all weather conditions, excluding ...

Cheng-Zhi Zou; Mei Gao; Mitchell D. Goldberg

2009-04-01T23:59:59.000Z

159

Constrained Interpolation Remap of Discrete Divergence Free Fields  

National Nuclear Security Administration (NNSA)

Shashkov M. 1 Shashkov M. 1 Constrained Interpolation Remap of Discrete Divergence Free Fields P.B. Bochev, * M. Shashkov † * Sandia National Laboratories, Org. 9214, Albuquerque, NM 87185 † Los Alamos National Laboratory, T-7, Los Alamos, NM 87545 We present a constrained interpolation (CI) algorithm for remapping of divergence free vector fields encoded as 2-cochains on a two-dimensional cell complex. On contractible domains discrete divergence free fields are 2-coboundaries and so they have potentials represented by 1-cochains. The algorithm takes advantage of this fact by using the discrete potential to effect the remapping of the divergence free field. The discrete potential is reconstructed and interpolated to the new cell complex. Application of

160

Applications of Algebraic Topology to Compatible Spatial Discretizations  

National Nuclear Security Administration (NNSA)

Hyman J. 1 Hyman J. 1 Applications of Algebraic Topology to Compatible Spatial Discretizations P. B. Bochev, * J. M. Hyman † * Sandia National Laboratories, Org. 9214, Albuquerque, NM 87185 † Los Alamos National Laboratory, T-7, Los Alamos, NM 87545 We provide a common framework for compatible discretizations using algebraic topology to guide our analysis. The main concept is the natural inner product on cochains, which induces a combinatorial Hodge theory. The framework comprises of mutually consistent operations of differentiation and integration, has a discrete Stokes theorem, and preserves the invariants of the DeRham cohomology groups. The latter allows for an elementary calculation of the kernel of the discrete Laplacian. Our framework provides an abstraction that includes examples

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


161

Diabatically Driven Discrete Propagation of Surface Fronts: A Numerical Analysis  

Science Conference Proceedings (OSTI)

Discrete frontal propagation has been identified as a process whereby a surface front discontinuously moves forward, without evidence of frontal passage across a mesoscale region. Numerical simulations are employed to examine the upper-level ...

George H. Bryan; J. Michael Fritsch

2000-07-01T23:59:59.000Z

162

A discrete model of energy-conserved wavefunction collapse  

E-Print Network (OSTI)

Energy nonconservation is a serious problem of dynamical collapse theories. In this paper, we propose a discrete model of energy-conserved wavefunction collapse. It is shown that the model is consistent with existing experiments and our macroscopic experience.

Gao, Shan

2013-01-01T23:59:59.000Z

163

Discrete Feature Approach for Heterogeneous Reservoir Production Enhancement  

Science Conference Proceedings (OSTI)

The report presents summaries of technology development for discrete feature modeling in support of the improved oil recovery (IOR) for heterogeneous reservoirs. In addition, the report describes the demonstration of these technologies at project study sites.

Dershowitz, William S.; Curran, Brendan; Einstein, Herbert; LaPointe, Paul; Shuttle, Dawn; Klise, Kate

2002-07-26T23:59:59.000Z

164

The cost of conservative synchronization in parallel discrete event simulations  

Science Conference Proceedings (OSTI)

This paper analytically studies the performance of a synchronous conservative parallel discrete-event simulation protocol. The class of models considered simulates activity in a physical domain, and possesses a limited ability to predict future behavior. ... Keywords: conservative synchronization

David M. Nicol

1993-04-01T23:59:59.000Z

165

Discrete multi-material interface reconstruction for volume fraction data  

Science Conference Proceedings (OSTI)

Material interface reconstruction (MIR) is the task of constructing boundary interfaces between regions of homogeneous material, while satisfying volume constraints, over a structured or unstructured spatial domain. In this paper, we present a discrete ...

J. C. Anderson; C. Garth; M. A. Duchaineau; K. I. Joy

2008-05-01T23:59:59.000Z

166

RFIDSim : a discrete event simulator for Radio Frequency Identification systems  

E-Print Network (OSTI)

This thesis presents RFIDSim, a discrete event process-oriented simulator designed to model Radio Frequency Identification (RFID) communication. The simulator focuses on the discovery and identification process of passive ...

Yu, Kenneth Kwan-Wai, 1979-

2003-01-01T23:59:59.000Z

167

AC transmission system planning choosing lines from a discrete set  

E-Print Network (OSTI)

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

Gilbertson, Eric W.

2013-04-24T23:59:59.000Z

168

Rapid modeling of field maintenance using discrete event simulation  

Science Conference Proceedings (OSTI)

Discrete event simulation has been applied to a wide range of applications areas due to its ability to represent stochastic systems over time. Maintenance, particularly field maintenance, is complex due to the interaction of different sub-systems of ...

Abdullah A. Alabdulkarim; Peter D. Ball; Ashutosh Tiwari

2011-12-01T23:59:59.000Z

169

Discrete Variational Calculus for B-spline Approximated Curves  

E-Print Network (OSTI)

We study variational problems for curves approximated by B-spline curves. We show that, one can obtain discrete Euler-Lagrange equations, for the data describing the approximated curves. Our main application is to the curve completion problem in 2D and 3D. In this case, the aim is to find various aesthetically pleasing solutions as opposed to a solution of a physical problem. The Lagrangians of interest are invariant under the special Euclidean group action for which B-spline approximated curves are well suited. Smooth Lagrangians with special Euclidean symmetries involve curvature, torsion, and arc length. Expressions in these, in the original coordinates, are highly complex. We show that, by contrast, relatively simple discrete Lagrangians offer excellent results for the curve completion problem. The methods we develop for the discrete curve completion problem are general and can be used to solve other discrete variational problems for B-spline curves.

Zhao, Jun

2010-01-01T23:59:59.000Z

170

Discrete Propagation in Numerically Simulated Nocturnal Squall Lines  

Science Conference Proceedings (OSTI)

Simulations of a typical midlatitude squall line were used to investigate a mechanism for discrete propagation, defined as convective initiation ahead of an existing squall line leading to a faster propagation speed for the storm complex. Radar ...

Robert G. Fovell; Gretchen L. Mullendore; Seung-Hee Kim

2006-12-01T23:59:59.000Z

171

Continuous-Time Distributed Observers with Discrete Communication  

E-Print Network (OSTI)

computation. Distributed estimation problems arise, for instance, in sensor networks, electric power grids data, and rely upon distributed mechanisms to merge local computations, such as intermediate dataContinuous-Time Distributed Observers with Discrete Communication Florian D¨orfler, Fabio

Bullo, Francesco

172

Lossless compression using the adaptive discrete cosine transform  

Science Conference Proceedings (OSTI)

This paper describes a technique using the adaptive discrete cosine transform for lossless waveform data compression. The technique is a variation on a two-stage lossless method that was developed by one of the authors. The earlier work employed an adaptive ... Keywords: ADPCM scheme, adaptive differential pulse code modulation-type, adaptive discrete cosine transform, data compression, encoding, integer residual sequence, lossless successive difference operation, lossless waveform data compression, storage, transmission, two-stage lossless method

L. Gerhardt; M. Fargues; G. Coutu

1995-10-01T23:59:59.000Z

173

Simulation of Atmospheric Variability  

Science Conference Proceedings (OSTI)

A spectral atmospheric circulation model is time-integrated for approximately 18 years. The model has a global computational domain and realistic geography and topography. The model undergoes an annual cycle as daily values of seasonally varying ...

Syukuro Manabe; Douglas G. Hahn

1981-11-01T23:59:59.000Z

174

Atmospheric Laser Communication  

Science Conference Proceedings (OSTI)

Atmospheric laser communication, often referred to as free-space optics (FSO) or free-space laser (FSL) communication, is similar to fiber optic cable in terms of carrier wavelength and bandwidth capability, but data are transmitted directly ...

Kenneth W. Fischer*Michael R. Witiw; Jeffrey A. Baars+; T. R. Oke

2004-05-01T23:59:59.000Z

175

Atmospheric Available Energy  

Science Conference Proceedings (OSTI)

The total potential energy of the atmosphere is the sum of its internal and gravitational energies. The portion of this total energy available to be converted into kinetic energy is determined relative to an isothermal, hydrostatic, equilibrium ...

Peter R. Bannon

2012-12-01T23:59:59.000Z

176

Diagnosis of Local Land–Atmosphere Feedbacks in India  

Science Conference Proceedings (OSTI)

Following the convective triggering potential (CTP)–humidity index (HIlow) framework by Findell and Eltahir, the sensitivity of atmospheric convection to soil moisture conditions is studied for India. Using the same slab model as Findell and ...

O. A. Tuinenburg; R. W. A. Hutjes; C. M. J. Jacobs; P. Kabat

2011-01-01T23:59:59.000Z

177

Atmospheric Circulation Changes Associated with Rainfall Anomalies over Tropical Brazil  

Science Conference Proceedings (OSTI)

During February–March 1981, striking contrasts existed in the rainfall distribution over most of Brazil and in the atmospheric circulation features over South America and the North and South Atlantic Oceans. Drier than normal conditions prevailed ...

Vernon E. Kousky

1985-11-01T23:59:59.000Z

178

Some Turbulence Characteristics in Stable Atmospheric Boundary Layer Flow  

Science Conference Proceedings (OSTI)

Atmospheric boundary layer measurements during stable and near neutral condition from seven sites in different kinds of terrain have been analyzed in order to find relationships among turbulence parameters.

Ann-Sofi Smedman

1991-03-01T23:59:59.000Z

179

Atmospheric Variability on a Zonally Symmetric Land Planet  

Science Conference Proceedings (OSTI)

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

Lai-Yung Leung; Gerald R. North

1991-08-01T23:59:59.000Z

180

Atmospheric Research Using Kites: Here We Go Again!  

Science Conference Proceedings (OSTI)

A recent campaign on Christmas Island in the equatorial Pacific has demonstrated that, at least under some conditions, simple and relatively inexpensive kites can serve as effective platforms for continuous monitoring of the tree atmosphere. ...

B. B. Balsley; C. L. Baisley; J. B. Williams; G. W. Tyrrell

1992-01-01T23:59:59.000Z

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


181

Mesoscale Modeling of Boundary Layer Refractivity and Atmospheric Ducting  

Science Conference Proceedings (OSTI)

In this study four mesoscale forecasting systems were used to investigate the four-dimensional structure of atmospheric refractivity and ducting layers that occur within evolving synoptic conditions over the eastern seaboard of the United States. ...

Tracy Haack; Changgui Wang; Sally Garrett; Anna Glazer; Jocelyn Mailhot; Robert Marshall

2010-12-01T23:59:59.000Z

182

An SQP-type solution method for constrained discrete-time optimal control problems  

Science Conference Proceedings (OSTI)

Keywords: constrained optimal control, discrete-time systems, hydroelectric power-station systems, structured nonlinear programming

E. Arnold; H. Puta

1994-03-01T23:59:59.000Z

183

THERMALLY DRIVEN ATMOSPHERIC ESCAPE  

Science Conference Proceedings (OSTI)

Accurately determining the escape rate from a planet's atmosphere is critical for determining its evolution. A large amount of Cassini data is now available for Titan's upper atmosphere and a wealth of data is expected within the next decade on escape from Pluto, Mars, and extra-solar planets. Escape can be driven by upward thermal conduction of energy deposited well below the exobase, as well as by nonthermal processes produced by energy deposited in the exobase region. Recent applications of a model for escape driven by upward thermal conduction, called the slow hydrodynamic escape model, have resulted in surprisingly large loss rates for the atmosphere of Titan, Saturn's largest moon. Based on a molecular kinetic simulation of the exobase region, these rates appear to be orders of magnitude too large. Therefore, the slow hydrodynamic model is evaluated here. It is shown that such a model cannot give a reliable description of the atmospheric temperature profile unless it is coupled to a molecular kinetic description of the exobase region. Therefore, the present escape rates for Titan and Pluto must be re-evaluated using the atmospheric model described here.

Johnson, Robert E., E-mail: rej@virginia.ed [Engineering Physics, Thornton Hall B102, University of Virginia, Charlottesville, VA 22902 (United States); Physics Department, New York University, New York, NY 10003 (United States)

2010-06-20T23:59:59.000Z

184

An energy absorbing far-field boundary condition for the elastic wave equation  

SciTech Connect

The authors present an energy absorbing non-reflecting boundary condition of Clayton-Engquist type for the elastic wave equation together with a discretization which is stable for any ratio of compressional to shear wave speed. They prove stability for a second order accurate finite-difference discretization of the elastic wave equation in three space dimensions together with a discretization of the proposed non-reflecting boundary condition. The stability proof is based on a discrete energy estimate and is valid for heterogeneous materials. The proof includes all six boundaries of the computational domain where special discretizations are needed at the edges and corners. The stability proof holds also when a free surface boundary condition is imposed on some sides of the computational domain.

Petersson, N A; Sjogreen, B

2008-07-15T23:59:59.000Z

185

ARM - Measurement - Atmospheric pressure  

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

pressure pressure ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Atmospheric pressure The pressure exerted by the atmosphere as a consequence of gravitational attraction exerted upon the "column" of air lying directly above the point in question. Categories Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments SONDE : Balloon-Borne Sounding System CO2FLX : Carbon Dioxide Flux Measurement Systems ECOR : Eddy Correlation Flux Measurement System

186

ARM - Measurement - Atmospheric temperature  

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

temperature temperature ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Atmospheric temperature The temperature indicated by a thermometer exposed to the air in a place sheltered from direct solar radiation. Categories Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AERI : Atmospheric Emitted Radiance Interferometer SONDE : Balloon-Borne Sounding System CO2FLX : Carbon Dioxide Flux Measurement Systems ECOR : Eddy Correlation Flux Measurement System

187

Article Atmospheric Science  

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

© The Author(s) 2012. This article is published with open access at Springerlink.com csb.scichina.com www.springer.com/scp © The Author(s) 2012. This article is published with open access at Springerlink.com csb.scichina.com www.springer.com/scp *Corresponding author (email: luchunsong110@gmail.com) Article Atmospheric Science February 2013 Vol.58 No.4-5: 545  551 doi: 10.1007/s11434-012-5556-6 A method for distinguishing and linking turbulent entrainment mixing and collision-coalescence in stratocumulus clouds LU ChunSong 1,2* , LIU YanGang 2 & NIU ShengJie 1 1 Key Laboratory for Atmospheric Physics and Environment of China Meteorological Administration, Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing University of Information Science and Technology, Nanjing 210044, China; 2 Atmospheric Sciences Division, Brookhaven National Laboratory, New York 11973, USA

188

ARM - Measurement - Atmospheric moisture  

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

moisture moisture ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Atmospheric moisture The moisture content of the air as indicated by several measurements including relative humidity, specific humidity, dewpoint, vapor pressure, water vapor mixing ratio, and water vapor density; note that precipitable water is a separate type. Categories Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AERI : Atmospheric Emitted Radiance Interferometer

189

BNL | Atmospheric Systems Research  

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

Atmospheric System Research is a DOE observation-based research program Atmospheric System Research is a DOE observation-based research program created to advance process-level understanding of the key interactions among aerosols, clouds, precipitation, radiation, dynamics, and thermodynamics, with the ultimate goal of reducing the uncertainty in global and regional climate simulations and projections. General areas of research at BNL under this program include studies of aerosol and cloud lifecycles, and cloud-aerosol-precipitation interactions. Contact Robert McGraw, 631.344.3086 aerosols Aerosol Life Cycle The strategic focus of the Aerosol Life Cycle research is observation-based process science-examining the properties and evolution of atmospheric aerosols. Observations come from both long-term studies conducted by the

190

Atmospheric Radiation Measurement Climate Research Facility | Argonne  

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

Atmospheric Radiation Measurement Climate Research Facility Atmospheric Radiation Measurement Climate Research Facility Argonne scientists study climate change 1 of 22 Argonne scientists study climate change The U.S. Department of Energy's Office of Science provided $60 million in ARRA funding for climate research to the Atmospheric Radiation Measurement (ARM) Climate Research Facility, a DOE national user facility that has been operating climate observing sites around the world for nearly two decades. These sites help scientists study clouds and their influence on the sun's radiant energy, which heats our planet. Above is one of the purchases: the Vaisala Present Weather Detector. It optically measures visibility, present weather, precipitation intensity, and precipitation type. It provides a measure of current weather conditions by combining measurements from three

191

Higher-order discrete variational problems with constraints  

E-Print Network (OSTI)

An interesting family of geometric integrators for Lagrangian systems can be defined using discretizations of the Hamilton's principle of critical action. This family of geometric integrators is called variational integrators. In this paper, we derive new variational integrators for higher-order lagrangian mechanical system subjected to higher-order constraints. From the discretization of the variational principles, we show that our methods are automatically symplectic and, in consequence, with a very good energy behavior. Additionally, the symmetries of the discrete Lagrangian imply that momenta is conserved by the integrator. Moreover, we extend our construction to variational integrators where the lagrangian is explicitly time-dependent. Finally, some motivating applications of higher-order problems are considered; in particular, optimal control problems for explicitly time-dependent underactuated systems and an interpolation problem on Riemannian manifolds.

Leonardo Colombo; David Martín de Diego; Marcela Zuccalli

2013-06-03T23:59:59.000Z

192

A New Discrete Transparent Boundary Condition for Standard and Wide Angle "Parabolic" Equations in Underwater Acoustics  

E-Print Network (OSTI)

in Underwater Acoustics ANTON ARNOLD1,2 AND MATTHIAS EHRHARDT1 1 Fachbereich Mathematik TU Berlin, MA 6­2 Stra�e in underwater acoustics, where they have been introduced by Tappert [31]. An account on the vast recent literature is given in the survey article [21]. In oceanography one wants to calculate the underwater

Ehrhardt, Matthias

193

Simulation of the atmospheric behavior for the environment of a small-scale wind turbine.  

E-Print Network (OSTI)

??This study investigates a method using computational fluid dynamics (CFD) to model low-elevation atmospheric conditions. There are three goals in this research: to analyze the… (more)

Nguyen, Viet

2011-01-01T23:59:59.000Z

194

Methodology for characterizing modeling and discretization uncertainties in computational simulation  

SciTech Connect

This research effort focuses on methodology for quantifying the effects of model uncertainty and discretization error on computational modeling and simulation. The work is directed towards developing methodologies which treat model form assumptions within an overall framework for uncertainty quantification, for the purpose of developing estimates of total prediction uncertainty. The present effort consists of work in three areas: framework development for sources of uncertainty and error in the modeling and simulation process which impact model structure; model uncertainty assessment and propagation through Bayesian inference methods; and discretization error estimation within the context of non-deterministic analysis.

ALVIN,KENNETH F.; OBERKAMPF,WILLIAM L.; RUTHERFORD,BRIAN M.; DIEGERT,KATHLEEN V.

2000-03-01T23:59:59.000Z

195

Environmental Evaluation on Atmosphere Radioactive Pollution of Uranium Mine Shaft Ventilation Exhausts  

Science Conference Proceedings (OSTI)

A study on calculation and evaluation on atmosphere radioactive pollution of uranium mine well ventilation exhaust gas is presented in this paper. Neutral atmosphere conditions were taken into consideration. Nuclear industry standards on safety protection ... Keywords: atmosphere pollution, radiation protection, environmental evaluation, control methods

Dong Xie; Zehua Liu; Jun Xiong; Jianxiang Liu

2012-03-01T23:59:59.000Z

196

Precomputed atmospheric scattering  

Science Conference Proceedings (OSTI)

We present a new and accurate method to render the atmosphere in real time from any viewpoint from ground level to outer space, while taking Rayleigh and Mie multiple scattering into account. Our method reproduces many effects of the scattering of light, ...

Eric Bruneton; Fabrice Neyret

2008-06-01T23:59:59.000Z

197

ARM ARM Atmospheric Radiation Measurement Atmospheric Radiation Measurement  

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

An Integrated Column Description An Integrated Column Description of the Atmosphere An Integrated Column Description of the Atmosphere Tom Ackerman Chief Scientist Tom Ackerman Chief Scientist ARM ARM Atmospheric Radiation Measurement Atmospheric Radiation Measurement Pacific Northwest National Laboratory Pacific Northwest National Laboratory The "other" Washington ARM ARM Atmospheric Radiation Measurement Atmospheric Radiation Measurement Credits to Credits to * Ric Cederwall * Xiquan Dong * Chuck Long * Jay Mace * Mark Miller * Robin Perez * Dave Turner and the rest of the ARM science team * Ric Cederwall * Xiquan Dong * Chuck Long * Jay Mace * Mark Miller * Robin Perez * Dave Turner and the rest of the ARM science team ARM ARM Atmospheric Radiation Measurement Atmospheric Radiation Measurement Outline Outline * A little philosophy

198

Winter marine atmospheric conditions over the Japan Sea  

E-Print Network (OSTI)

near 100°E, 50°N, and the Aleutian Cyclone (Low) in the Gulfof the Siberian High (H), the Aleutian Low (L), and the mainto the northwest, and the Aleutian Low to the east. At 850

2004-01-01T23:59:59.000Z

199

Winter marine atmospheric conditions over the Japan Sea  

E-Print Network (OSTI)

data reveals the strong, offshore wind speed gradients thatVCSAO event periods. offshore winds as experienced by the

2004-01-01T23:59:59.000Z

200

Winter marine atmospheric conditions over the Japan Sea  

E-Print Network (OSTI)

suggestive of lee-side subsidence and adiabatic warming. Thesurface air dried, and subsidence returned above 12 of 26and column warmed while the subsidence increased and the

2004-01-01T23:59:59.000Z

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


201

Effects of Changing Atmospheric Conditions on Wind Turbine Performance (Poster)  

SciTech Connect

Multi-megawatt, utility-scale wind turbines operate in turbulent and dynamic winds that impact turbine performance in ways that are gradually becoming better understood. This poster presents a study made using a turbulent flow field simulator (TurbSim) and a Turbine aeroelastic simulator (FAST) of the response of a generic 1.5 MW wind turbine to changing inflow. The turbine power output is found to be most sensitive to wind speed and turbulence intensity, but the relationship depends on the wind speed with respect to the turbine's rated wind speed. Shear is found to be poorly correlated to power. A machine learning method called 'regression trees' is used to create a simple model of turbine performance that could be used as part of the wind resource assessment process. This study has used simple flow fields and should be extended to more complex flows, and validated with field observations.

Clifton, A.

2012-12-01T23:59:59.000Z

202

DISCRETE SYMMETRIES OF THE BLACK-SCHOLES EQUATION  

E-Print Network (OSTI)

DISCRETE SYMMETRIES OF THE BLACK-SCHOLES EQUATION Gheorghe Silberberg Abstract The paper computes the full automorphism group of the Lie al- gebra associated to the Black-Scholes equation and determines symmetries. The present paper applies the whole procedure to the famous Black- Scholes partial differential

203

Solving Elliptic Curve Discrete Logarithm Problems Using Weil Descent  

E-Print Network (OSTI)

We provide the first cryptographically interesting instance of the elliptic curve discrete logarithm problem which resists all previously known attacks, but which can be solved with modest computer resources using the Weil descent attack methodology of Frey. We report on our implementation of index-calculus methods for hyperelliptic curves over characteristic two finite fields, and discuss the cryptographic implications of our results.

Michael Jacobson; Alfred Menezes; Andreas Stein

2001-01-01T23:59:59.000Z

204

Simulation of mobile networks using discrete event system specification theory  

Science Conference Proceedings (OSTI)

The fourth generation (4G) of mobile telecommunication technology provides ultra-band internet access for mobile devices such as smartphones, tablets, and laptops. One of the challenges in the Long Term Evolution (LTE) 4G networks is the low data rate ... Keywords: DEVS, discrete event system specification, mobile networks

Mohammad Moallemi, Gabriel Wainer, Shafagh Jafer, Gary Boudreau, Ronald Casselman

2013-04-01T23:59:59.000Z

205

Discreteness and the transmission of light from distant sources  

SciTech Connect

We model the classical transmission of a massless scalar field from a source to a detector on a background causal set. The predictions do not differ significantly from those of the continuum. Thus, introducing an intrinsic inexactitude to lengths and durations--or more specifically, replacing the Lorentzian manifold with an underlying discrete structure--need not disrupt the usual dynamics of propagation.

Dowker, Fay [Blackett Laboratory, Imperial College, London SW7 2AZ (United Kingdom); Henson, Joe; Sorkin, Rafael D. [Perimeter Institute, 31 Caroline Street N., Waterloo, N2L 2Y5 (Canada)

2010-11-15T23:59:59.000Z

206

Optimization strategies for discrete multi-material stiffness optimization  

Science Conference Proceedings (OSTI)

Design of composite laminated lay-ups are formulated as discrete multi-material selection problems. The design problem can be modeled as a non-convex mixed-integer optimization problem. Such problems are in general only solvable to global optimality ... Keywords: Integer optimization, Laminated composite materials, Optimal design, Sensitivity analysis, Solution strategies

Christian Frier Hvejsel; Erik Lund; Mathias Stolpe

2011-08-01T23:59:59.000Z

207

DISPERSION AND DISSIPATION ERRORS OF TWO FULLY DISCRETE DISCONTINUOUS GALERKIN  

E-Print Network (OSTI)

-dimensional Euler equations in gas dynamics. There has been abundant study on the dispersion analysis of many nuDISPERSION AND DISSIPATION ERRORS OF TWO FULLY DISCRETE DISCONTINUOUS GALERKIN METHODS HE YANG, FENGYAN LI, AND JIANXIAN QIU Abstract. The dispersion and dissipation properties of numerical meth- ods

Li, Fengyan

208

Power system failure analysis by using the discrete wavelet transform  

Science Conference Proceedings (OSTI)

Voltage variations are the most common power quality events that may result in corruption of different industrial processes. The electric power utility industry requires significant improvement in the quality of power provided to customers during faults ... Keywords: discrete wavelet transform, power system failure, wavelet entropy

Ismail Yilmazlar; Gulden Kokturk

2010-05-01T23:59:59.000Z

209

Discrete-event simulation in Java: a practitioner's experience  

Science Conference Proceedings (OSTI)

The experience of a simulation practitioner with development of a new Java simulation engine and its application to a large simulation model is described. Our simulation engine is implemented as a simple extension of the Java programming language and ... Keywords: Java, discrete-event simulation, parallel processing, practitioner, supply chain

D. H. King; Harvey S. Harrison

2010-07-01T23:59:59.000Z

210

First–Order Representations of Discrete Linear MultidimensionalSystems  

Science Conference Proceedings (OSTI)

The classical local state–space models for discrete multidimensional linear systems, as proposed by Roesser or Fornasini and Marchesini, require causality of the resulting transfer matrices. We consider a generalization comprising non-causal ... Keywords: (Laurent) polynomial matrices, behavior, first–, input–, kernel and image representation, linear fractional transformation, minimality, order representation, output structure, properness

Eva Zerz

2000-10-01T23:59:59.000Z

211

Bounds for the price of discrete arithmetic Asian options  

Science Conference Proceedings (OSTI)

In this paper the pricing of European-style discrete arithmetic Asian options with fixed and floating strike is studied by deriving analytical lower and upper bounds. In our approach we use a general technique for deriving upper (and lower) bounds for ... Keywords: Asian option, Black and Scholes setting, analytical bounds, comonotonicity

M. Vanmaele; G. Deelstra; J. Liinev; J. Dhaene; M. J. Goovaerts

2006-01-01T23:59:59.000Z

212

Bounds for the price of discrete arithmetic Asian options  

Science Conference Proceedings (OSTI)

In this paper the pricing of European-style discrete arithmetic Asian options with fixed and floating strike is studied by deriving analytical lower and upper bounds. In our approach we use a general technique for deriving upper (and lower) bounds for ... Keywords: Analytical bounds, Asian option, Black and Scholes setting, Comonotonicity

M. Vanmaele; G. Deelstra; J. Liinev; J. Dhaene; M. J. Goovaerts

2006-01-01T23:59:59.000Z

213

Hidden maintenance opportunities in discrete and complex production lines  

Science Conference Proceedings (OSTI)

In manufacturing systems, many maintenance tasks require equipment to be stopped in order to safely perform them. However, such stoppage cannot last for too long since it might directly result in short-term production losses. In this paper, we investigate ... Keywords: Complex manufacturing systems, Discrete production, Maintenance opportunity windows

Xi Gu; Seungchul Lee; Xinran Liang; Mark Garcellano; Mark Diederichs; Jun Ni

2013-09-01T23:59:59.000Z

214

Specification of Discrete Event Models for Fire Spreading  

Science Conference Proceedings (OSTI)

The fire-spreading phenomenon is highly complex, and existing mathematical models of fire are so complex themselves that any possibility of analytical solution is precluded. Instead, there has been some success when studying fire spread by means of simulation. ... Keywords: Cell-DEVS, Cellular Automata, DEVS, Discrete event simulation, fire spread

Alexandre Muzy; Eric Innocenti; Antoine Aiello; Jean-François Santucci; Gabriel Wainer

2005-02-01T23:59:59.000Z

215

Sparse image representation by discrete cosine/spline based dictionaries  

E-Print Network (OSTI)

Mixed dictionaries generated by cosine and B-spline functions are considered. It is shown that, by highly nonlinear approaches such as Orthogonal Matching Pursuit, the discrete version of the proposed dictionaries yields a significant gain in the sparsity of an image representation.

Bowley, James

2009-01-01T23:59:59.000Z

216

Numerical Discretization of Rotated Diffusion Operators in Ocean Models  

Science Conference Proceedings (OSTI)

A method to improve the behavior of the numerical discretization of a rotated diffusion operator such as, for example, the isopycnal diffusion parameterization used in large-scale ocean models based on the so-called z-coordinate system is ...

J-M. Beckers; H. Burchard; E. Deleersnijder; P. P. Mathieu

2000-08-01T23:59:59.000Z

217

Estimating discrete Markov models from various incomplete data schemes  

Science Conference Proceedings (OSTI)

The parameters of a discrete stationary Markov model are transition probabilities between states. Traditionally, data consist in sequences of observed states for a given number of individuals over the whole observation period. In such a case, the estimation ... Keywords: Adaptive MCMC, Bayesian inference, Gaussian copulas, Industrial reliability, Markov models, Missing data

Alberto Pasanisi; Shuai Fu; Nicolas Bousquet

2012-09-01T23:59:59.000Z

218

Physics in discrete spaces (A): Space-Time organization  

E-Print Network (OSTI)

We put forward a model of discrete physical space that can account for the structure of space- time, give an interpretation to the postulates of quantum mechanics and provide a possible explanation to the organization of the standard model of particles.

P. Peretto

2010-12-29T23:59:59.000Z

219

Discrete-element modeling of particulate aerosol flows  

Science Conference Proceedings (OSTI)

A multiple-time step computational approach is presented for efficient discrete-element modeling of aerosol flows containing adhesive solid particles. Adhesive aerosol particulates are found in numerous dust and smoke contamination problems, including ... Keywords: Aerosols, Aggregation, Particle adhesion, Particulate flow

J. S. Marshall

2009-03-01T23:59:59.000Z

220

Concept inventories in computer science for the topic discrete mathematics  

Science Conference Proceedings (OSTI)

This report describes concept inventories, specialized assessment instruments that enable educational researchers to investigate student (mis)understandings of concepts in a particular domain. While students experience a concept inventory as a set of ... Keywords: assessment, assessment tools, concept inventory, discrete mathematics, distractors, misconceptions

Vicki L. Almstrum; Peter B. Henderson; Valerie Harvey; Cinda Heeren; William Marion; Charles Riedesel; Leen-Kiat Soh; Allison Elliott Tew

2006-12-01T23:59:59.000Z

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


221

Optimisation-based scheduling: A discrete manufacturing case study  

Science Conference Proceedings (OSTI)

This work presents the development and implementation of a production scheduling system for an electrical appliance manufacturer. Based on recent advances in optimisation-based scheduling approaches, two different software architectures based on two ... Keywords: Discrete manufacturing, Electrical appliances, Mixed-integer linear programming, Optimization-based scheduling

Michael C. Georgiadis; Aaron A. Levis; Panagiotis Tsiakis; Ioannis Sanidiotis; Constantinos C. Pantelides; Lazaros G. Papageorgiou

2005-08-01T23:59:59.000Z

222

Frame sequential interpolation for discrete level-of-detail rendering  

Science Conference Proceedings (OSTI)

In this paper we present a method for automatic interpolation between adjacent discrete levels of detail to achieve smooth LOD changes in image space. We achieve this by breaking the problem into two passes: We render the two LOD levels individually ...

Daniel Scherzer; Michael Wimmer

2008-06-01T23:59:59.000Z

223

The theory of deadlock avoidance via discrete control  

Science Conference Proceedings (OSTI)

Deadlock in multithreaded programs is an increasingly important problem as ubiquitous multicore architectures force parallelization upon an ever wider range of software. This paper presents a theoretical foundation for dynamic deadlock avoidance in concurrent ... Keywords: concurrent programming, discrete control theory, dynamic deadlock avoidance, multicore processors, multithreaded programming, parallel programming

Yin Wang; Stéphane Lafortune; Terence Kelly; Manjunath Kudlur; Scott Mahlke

2009-01-01T23:59:59.000Z

224

ON THE STABILITY OF SUPER-EARTH ATMOSPHERES  

SciTech Connect

We investigate the stability of super-Earth atmospheres around M stars using a seven-parameter, analytical framework. We construct stability diagrams in the parameter space of exoplanetary radius versus semimajor axis and elucidate the regions in which the atmospheres are stable against the condensation of their major constituents, out of the gas phase, on their permanent nightside hemispheres. We find that super-Earth atmospheres that are nitrogen-dominated (Earth-like) occupy a smaller region of allowed parameter space, compared to hydrogen-dominated atmospheres, because of the dual effects of diminished advection and enhanced radiative cooling. Furthermore, some super-Earths which reside within the habitable zones of M stars may not possess stable atmospheres, depending on the mean molecular weight and infrared photospheric pressure of their atmospheres. We apply our stability diagrams to GJ 436b and GJ 1214b, and demonstrate that atmospheric compositions with high mean molecular weights are disfavored if these exoplanets possess solid surfaces and shallow atmospheres. Finally, we construct stability diagrams tailored to the Kepler data set, for G and K stars, and predict that about half of the exoplanet candidates are expected to harbor stable atmospheres if Earth-like conditions are assumed. We include 55 Cancri e and CoRoT-7b in our stability diagram for G stars.

Heng, Kevin [ETH Zuerich, Institute for Astronomy, Wolfgang-Pauli-Strasse 27, CH-8093, Zuerich (Switzerland); Kopparla, Pushkar [ETH Zuerich, Institute for Atmospheric and Climate Science, Universitaetstrasse 16, CH-8092, Zuerich (Switzerland)

2012-07-20T23:59:59.000Z

225

Hydrostatic Adjustment in Nonisothermal Atmospheres  

Science Conference Proceedings (OSTI)

The author examines hydrostatic adjustment due to heating in two nonisothermal atmospheres. In the first case both the temperature and lapse rate decrease with height; in the second case the atmosphere consists of a troposphere with constant ...

Dean G. Duffy

2003-01-01T23:59:59.000Z

226

Efficient rendering of atmospheric phenomena  

Science Conference Proceedings (OSTI)

Rendering of atmospheric bodies involves modeling the complex interaction of light throughout the highly scattering medium of water and air particles. Scattering by these particles creates many well-known atmospheric optical phenomena including rainbows, ...

Kirk Riley; David S. Ebert; Martin Kraus; Jerry Tessendorf; Charles Hansen

2004-06-01T23:59:59.000Z

227

A Numerical Study on the Atmospheric Circulation over the Midlatitude North Pacific during the Last Glacial Maximum  

Science Conference Proceedings (OSTI)

The dynamics of the atmospheric circulation change over the midlatitude North Pacific under the boundary conditions during the last glacial maximum (LGM) have been studied by atmospheric general circulation models (GCMs) with different ocean ...

Wataru Yanase; Ayako Abe-Ouchi

2010-01-01T23:59:59.000Z

228

ARM - Measurement - Atmospheric turbulence  

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

turbulence turbulence ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Atmospheric turbulence High frequency velocity fluctuations that lead to turbulent transport of momentum, heat, mositure, and passive scalars, and often expressed in terms of variances and covariances. Categories Atmospheric State, Surface Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments CO2FLX : Carbon Dioxide Flux Measurement Systems ECOR : Eddy Correlation Flux Measurement System

229

Differential atmospheric tritium sampler  

DOE Patents (OSTI)

An atmospheric tritium sampler is provided which uses a carrier gas comprised of hydrogen gas and a diluting gas, mixed in a nonexplosive concentration. Sample air and carrier gas are drawn into and mixed in a manifold. A regulator meters the carrier gas flow to the manifold. The air sample/carrier gas mixture is pulled through a first moisture trap which adsorbs water from the air sample. The mixture then passes through a combustion chamber where hydrogen gas in the form of H.sub.2 or HT is combusted into water. The manufactured water is transported by the air stream to a second moisture trap where it is adsorbed. The air is then discharged back into the atmosphere by means of a pump.

Griesbach, Otto A. (Langhorne, PA); Stencel, Joseph R. (Skillman, NJ)

1990-01-01T23:59:59.000Z

230

Atmospheric Release Advisory Capability  

SciTech Connect

The Atmospheric Release Advisory Capability (ARAC) project is a Department of Energy (DOE) sponsored real-time emergency response service available for use by both federal and state agencies in case of a potential or actual atmospheric release of nuclear material. The project, initiated in 1972, is currently evolving from the research and development phase to full operation. Plans are underway to expand the existing capability to continuous operation by 1984 and to establish a National ARAC Center (NARAC) by 1988. This report describes the ARAC system, its utilization during the past two years, and plans for its expansion during the next five to six years. An integral part of this expansion is due to a very important and crucial effort sponsored by the Defense Nuclear Agency to extend the ARAC service to approximately 45 Department of Defense (DOD) sites throughout the continental US over the next three years.

Dickerson, M.H.; Gudiksen, P.H.; Sullivan, T.J.

1983-02-01T23:59:59.000Z

231

Atmospheric Mercury Research Update  

Science Conference Proceedings (OSTI)

This report is a summary and analysis of research findings on utility and environmental mercury from 1997 to 2003. The update categorizes and describes recent work on mercury in utility-burned coal and its route through power plants, the measures for its control, and its fate in the environment following emissions from utility stacks. This fate includes atmospheric chemistry and transport, deposition to land and water surfaces, aquatic cycling, the dynamics of mercury in freshwater fish food webs, and th...

2004-03-30T23:59:59.000Z

232

On combining local DCT with preprocessing sequence for face recognition under varying lighting conditions  

Science Conference Proceedings (OSTI)

Face recognition under varying lighting conditions remains an unsolved problem. In this work, a new photometric normalisation method based on local Discrete Cosine Transform in the logarithmic domain is proposed. The method is experimentally evaluated ...

Heydi Méndez-Vázquez; Josef Kittler; Chi-Ho Chan; Edel García-Reyes

2010-11-01T23:59:59.000Z

233

ORISE: Climate and Atmospheric Research  

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

Climate and Atmospheric Research Climate and Atmospheric Research Capabilities Overview U.S. Climate Reference Network U.S. Historical Climate Network Contact Us Oak Ridge Institute for Science Education Climate and Atmospheric Research The Oak Ridge Institute for Science and Education (ORISE) partners with the National Oceanic and Atmospheric Administration's Atmospheric Turbulence and Diffusion Division (ATDD) to conduct climate research focused on issues of national and global importance. Research is performed with personnel support from ORISE's Independent Environmental Assessment and Verification (IEAV) programs, as well as in collaboration with scientists and engineers from Oak Ridge National Laboratory (ORNL), and numerous other organizations, government agencies, universities and private research institutions.

234

Quadratic Galerkin Finite Element Schemes for the Vertical Discretization of Numerical Forecast Models  

Science Conference Proceedings (OSTI)

A finite element scheme with second-order basis functions is introduced for vertical discretization using a spectral model for horizontal discretization. The basis functions are required to be continuous, and no assumption is made concerning the ...

J. Steppeler

1987-08-01T23:59:59.000Z

235

Bounded skew high-order resolution schemes for the discrete ordinates method  

Science Conference Proceedings (OSTI)

The discrete ordinates method for the solution of the radiative heat transfer equation suffers from two main shortcomings, namely ray effects and numerical smearing. Spatial discretization, which is the cause of numerical smearing, constitutes the subject ...

P. J. Coelho

2002-01-01T23:59:59.000Z

236

An Unsuspected Boundary-Induced Temporal Computational Mode in a Two-Time-Level Discretization  

Science Conference Proceedings (OSTI)

Normal-mode analyses are applied to various discrete forms of the one-dimensional, linearized, vertical acoustic equations in a height-based coordinate. First, the temporally discrete, spatially continuous equations are considered and the normal ...

Andrew Staniforth; Nigel Wood

2005-03-01T23:59:59.000Z

237

On the Correlated k-Distribution Method for Radiative Transfer in Nonhomogeneous Atmospheres  

Science Conference Proceedings (OSTI)

The correlated k-distribution method for radiative transfer in nonhomogeneous atmospheres is discussed in terms of the physical and mathematical conditions under which this method is valid. Two correlated conditions are necessary and sufficient ...

Qiang Fu; K. N. Liou

1992-11-01T23:59:59.000Z

238

The Diurnal Cycle of Land–Atmosphere Interactions across Oklahoma’s Winter Wheat Belt  

Science Conference Proceedings (OSTI)

This manuscript documents the impact of Oklahoma’s winter wheat belt (WWB) on the near-surface atmosphere by comparing the diurnal cycle of meteorological conditions within the WWB relative to conditions in adjacent counties before and after the ...

Matthew J. Haugland; Kenneth C. Crawford

2005-01-01T23:59:59.000Z

239

Condition assessment of nonlinear processes  

DOE Patents (OSTI)

There is presented a reliable technique for measuring condition change in nonlinear data such as brain waves. The nonlinear data is filtered and discretized into windowed data sets. The system dynamics within each data set is represented by a sequence of connected phase-space points, and for each data set a distribution function is derived. New metrics are introduced that evaluate the distance between distribution functions. The metrics are properly renormalized to provide robust and sensitive relative measures of condition change. As an example, these measures can be used on EEG data, to provide timely discrimination between normal, preseizure, seizure, and post-seizure states in epileptic patients. Apparatus utilizing hardware or software to perform the method and provide an indicative output is also disclosed.

Hively, Lee M. (Philadelphia, TN); Gailey, Paul C. (Athens, OH); Protopopescu, Vladimir A. (Knoxville, TN)

2002-01-01T23:59:59.000Z

240

PNNL: FCSD: Atmospheric Sciences & Global Change: Programs &...  

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

Programs & Facilities Atmospheric Measurements Laboratory Atmospheric Radiation Measurement (ARM) Program and ARM Climate Research Facility ARM Aerial Facility Environmental...

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


241

An adaptive synchronization protocol for parallel discrete event simulation  

SciTech Connect

Simulation, especially discrete event simulation (DES), is used in a variety of disciplines where numerical methods are difficult or impossible to apply. One problem with this method is that a sufficiently detailed simulation may take hours or days to execute, and multiple runs may be needed in order to generate the desired results. Parallel discrete event simulation (PDES) has been explored for many years as a method to decrease the time taken to execute a simulation. Many protocols have been developed which work well for particular types of simulations, but perform poorly when used for other types of simulations. Often it is difficult to know a priori whether a particular protocol is appropriate for a given problem. In this work, an adaptive synchronization method (ASM) is developed which works well on an entire spectrum of problems. The ASM determines, using an artificial neural network (ANN), the likelihood that a particular event is safe to process.

Bisset, K.R.

1998-12-01T23:59:59.000Z

242

Four-body continuum-discretized coupled-channels calculations  

SciTech Connect

The development of a continuum-bin scheme of discretization for three-body projectiles is necessary for studies of reactions of Borromean nuclei such as {sup 6}He within the continuum-discretized coupled-channels approach. Such a procedure, for constructing bin states on selected continuum energy intervals, is formulated and applied for the first time to reactions of a three-body projectile. The continuum representation uses the eigenchannel expansion of the three-body S matrix. The method is applied to the challenging case of the {sup 6}He+{sup 208}Pb reaction at 22 MeV, where an accurate treatment of both the Coulomb and the nuclear interactions with the target is necessary.

Rodriguez-Gallardo, M. [Instituto de Estructura de la Materia, CSIC, Serrano 123, E-28006 Madrid (Spain); Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla (Spain); Centro de Fisica Nuclear, Universidade de Lisboa, Avenida Prof. Gama Pinto 2, P-1649-003 Lisboa (Portugal); Arias, J. M.; Moro, A. M. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla (Spain); Gomez-Camacho, J. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla (Spain); Centro Nacional de Aceleradores, Avenida Thomas A. Edison, E-41092 Sevilla (Spain); Thompson, I. J. [Lawrence Livermore National Laboratory, Physical Science Directorate, P. O. Box 808, L-414, Livermore, California 94551 (United States); Tostevin, J. A. [Department of Physics, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

2009-11-15T23:59:59.000Z

243

The discrete Kalman filtering approach for seismic signals deconvolution  

SciTech Connect

Seismic signals are a convolution of reflectivity and seismic wavelet. One of the most important stages in seismic data processing is deconvolution process; the process of deconvolution is inverse filters based on Wiener filter theory. This theory is limited by certain modelling assumptions, which may not always valid. The discrete form of the Kalman filter is then used to generate an estimate of the reflectivity function. The main advantage of Kalman filtering is capability of technique to handling continually time varying models and has high resolution capabilities. In this work, we use discrete Kalman filter that it was combined with primitive deconvolution. Filtering process works on reflectivity function, hence the work flow of filtering is started with primitive deconvolution using inverse of wavelet. The seismic signals then are obtained by convoluting of filtered reflectivity function with energy waveform which is referred to as the seismic wavelet. The higher frequency of wavelet gives smaller wave length, the graphs of these results are presented.

Kurniadi, Rizal; Nurhandoko, Bagus Endar B. [Departement of Physics Intitut Teknologi Bandung, Jl. Ganesha 10 Bandung (Indonesia)

2012-06-20T23:59:59.000Z

244

Relative Fisher information of discrete classical orthogonal polynomials  

E-Print Network (OSTI)

The analytic information theory of discrete distributions was initiated in 1998 by C. Knessl, P. Jacquet and S. Szpankowski who addressed the precise evaluation of the Renyi and Shannon entropies of the Poisson, Pascal (or negative binomial) and binomial distributions. They were able to derive various asymptotic approximations and, at times, lower and upper bounds for these quantities. Here we extend these investigations in a twofold way. First, we consider a much larger class of distributions, the Rakhmanov distributions $\\rho_n(x)=\\omega(x)y_n^2(x)$, where $\\{y_n(x)\\}$ denote the sequences of discrete hypergeometric-type polynomials which are orthogonal with respect to the weight function $\\omega(x)$ of Poisson, Pascal, binomial and hypergeometric types; that is the polynomials of Charlier, Meixner, Kravchuk and Hahn. Second, we obtain the explicit expressions for the relative Fisher information of these four families of Rakhmanov distributions with respect to their respective weight functions.

Jesus S. Dehesa; Pablo Sánchez-Moreno; Rafael J. Yáńez

2013-05-20T23:59:59.000Z

245

A study of discrete and continuum joint modeling techniques  

SciTech Connect

This paper presents the results of a numerical and experimental study in which finite element and discrete element techniques were used to analyze a layered polycarbonate plate model subjected to uniaxial compression. Also, the two analysis techniques were used to compute the response of an eight meter diameter drift in jointed-rock. The drift was subjected to in-situ and far-field induced thermal stresses. The finite element analyses used a continuum rock model to represent the jointed-rock. A comparison of the analyses showed that the finite element continuum joint model consistently predicted less joint slippage than did the discrete element analyses, although far-field displacements compared well.

Jung, J.; Brown, S.R.

1992-05-01T23:59:59.000Z

246

Higher order discretization methods for the numerical simulation of fluidized beds  

SciTech Connect

Numerical models of fluidized beds based on the multiphase mass and momentum balance equations for gas and solids phases continue to be developed by several groups of researchers around the world. It has been demonstrated that the same set of equations is able to describe a wide range of fluidization conditions, ranging from bubbling to circulating fluidized beds. The results of bubbling bed simulations, plots of void fraction distribution, show the formation and propagation of high void fraction regions, called bubbles. This study shows that these problems are numerical artifacts of using first order accurate discretization schemes and coarse grids and are not due to a fundamental difficulty with the theory. This study was motivated by the observation that the shape of the gas hold up profile described by Sokolichin et al. is similar to that of the shape of bubbles in a fluidized bed. Second-order accurate discretization schemes were included in a multiphase flow model of fluidized beds called MFIX. It is shown here that the bubble shape predicted with a second order accurate scheme is rounded. The simulations were conducted for long durations (5 s) and the results did not show the fountain formation at the bed surface. It appears that the fountain formation is caused by coarse grids and low physical viscosity of the solids phase.

Syamlal, M.

1997-01-01T23:59:59.000Z

247

GPU accelerated simulations of 3D deterministic particle transport using discrete ordinates method  

Science Conference Proceedings (OSTI)

Graphics Processing Unit (GPU), originally developed for real-time, high-definition 3D graphics in computer games, now provides great faculty in solving scientific applications. The basis of particle transport simulation is the time-dependent, multi-group, inhomogeneous Boltzmann transport equation. The numerical solution to the Boltzmann equation involves the discrete ordinates (S{sub n}) method and the procedure of source iteration. In this paper, we present a GPU accelerated simulation of one energy group time-independent deterministic discrete ordinates particle transport in 3D Cartesian geometry (Sweep3D). The performance of the GPU simulations are reported with the simulations of vacuum boundary condition. The discussion of the relative advantages and disadvantages of the GPU implementation, the simulation on multi GPUs, the programming effort and code portability are also reported. The results show that the overall performance speedup of one NVIDIA Tesla M2050 GPU ranges from 2.56 compared with one Intel Xeon X5670 chip to 8.14 compared with one Intel Core Q6600 chip for no flux fixup. The simulation with flux fixup on one M2050 is 1.23 times faster than on one X5670.

Gong Chunye, E-mail: gongchunye@gmail.com [School of Computer Science, National University of Defense Technology, Changsha 410073 (China); Liu Jie, E-mail: liujie@nudt.edu.cn [School of Computer Science, National University of Defense Technology, Changsha 410073 (China); Chi Lihua [School of Computer Science, National University of Defense Technology, Changsha 410073 (China); Huang Haowei [Institut fuer Informatik, Technische Universitaet Muenchen, D-85748 Garching, Munich (Germany); Fang Jingyue [School of Physics and Mathematics, National University of Defense Technology, Changsha 410073 (China); Gong Zhenghu [School of Computer Science, National University of Defense Technology, Changsha 410073 (China)

2011-07-01T23:59:59.000Z

248

Thermalized polarization dynamics of a discrete optical waveguide system with four-wave mixing  

E-Print Network (OSTI)

Statistical mechanics of two coupled vector fields is studied in the tight-binding model that describes propagation of polarized light in discrete waveguides in the presence of the four-wave mixing. The energy and power conservation laws enable the formulation of the equilibrium properties of the polarization state in terms of the Gibbs measure with positive temperature. The transition line $T=\\infty$ is established beyond which the discrete vector solitons are created. Also in the limit of the large nonlinearity an analytical expression for the distribution of Stokes parameters is obtained which is found to be dependent only on the statistical properties of the initial polarization state and not on the strength of nonlinearity. The evolution of the system to the final equilibrium state is shown to pass through the intermediate stage when the energy exchange between the waveveguides is still negligible. The distribution of the Stokes parameters in this regime has a complex multimodal structure strongly dependent on the nonlinear coupling coefficients and the initial conditions.

S. A. Derevyanko

2013-07-11T23:59:59.000Z

249

Biometric cryptosystem based on discretized fingerprint texture descriptors  

Science Conference Proceedings (OSTI)

This paper focuses on a biometric cryptosystem implementation and evaluation based on a number of fingerprint texture descriptors. The texture descriptors, namely, the Gabor filter-based FingerCode, a local binary pattern (LBP), and a local direction ... Keywords: BCH, BPA, Biometric discretization, DROBA, ECC, EER, Error-correcting code, FAR, FCS, FRR, Fingerprint texture descriptors, Fuzzy commitment scheme, GAR, LBP, LCM, LDP, LDPC, LDerivP, Local binary pattern, MPA, PEG, ROI, SPA

Yadigar Imamverdiyev; Andrew Beng Jin Teoh; Jaihie Kim

2013-04-01T23:59:59.000Z

250

Discrete diffusion Monte Carlo for frequency-dependent radiative transfer  

SciTech Connect

Discrete Diffusion Monte Carlo (DDMC) is a technique for increasing the efficiency of Implicit Monte Carlo radiative-transfer simulations. In this paper, we develop an extension of DDMC for frequency-dependent radiative transfer. We base our new DDMC method on a frequency-integrated diffusion equation for frequencies below a specified threshold. Above this threshold we employ standard Monte Carlo. With a frequency-dependent test problem, we confirm the increased efficiency of our new DDMC technique.

Densmore, Jeffrey D [Los Alamos National Laboratory; Kelly, Thompson G [Los Alamos National Laboratory; Urbatish, Todd J [Los Alamos National Laboratory

2010-11-17T23:59:59.000Z

251

Connecting Blackbody Radiation, Relativity, and Discrete Charge in Classical Electrodynamics  

E-Print Network (OSTI)

It is suggested that an understanding of blackbody radiation within classical physics requires the presence of classical electromagnetic zero-point radiation, the restriction to relativistic (Coulomb) scattering systems, and the use of discrete charge. The contrasting scaling properties of nonrelativistic classical mechanics and classical electrodynamics are noted, and it is emphasized that the solutions of classical electrodynamics found in nature involve constants which connect together the scales of length, time, and energy. Indeed, there are analogies between the electrostatic forces for groups of particles of discrete charge and the van der Waals forces in equilibrium thermal radiation. The differing Lorentz- or Galilean-transformation properties of the zero-point radiation spectrum and the Rayleigh-Jeans spectrum are noted in connection with their scaling properties. Also, the thermal effects of acceleration within classical electromagnetism are related to the existence of thermal equilibrium within a gravitational field. The unique scaling and phase-space properties of a discrete charge in the Coulomb potential suggest the possibility of an equilibrium between the zero-point radiation spectrum and matter which is universal (independent of the particle mass), and an equilibrium between a universal thermal radiation spectrum and matter where the matter phase space depends only upon the ratio mc^2/kT. The observations and qualitative suggestions made here run counter to the ideas of currently accepted quantum physics.

Timothy H. Boyer

2006-04-28T23:59:59.000Z

252

On discrete symmetries for a whole Abelian model  

Science Conference Proceedings (OSTI)

Considering the whole concept applied to gauge theory a nonlinear abelian model is derived. A next step is to understand on the model properties. At this work, it will be devoted to discrete symmetries. For this, we will work based in two fields reference systems. This whole gauge symmetry allows to be analyzed through different sets which are the constructor basis {l_brace}D{sub {mu}},X{sup i}{sub {mu}}{r_brace} and the physical basis {l_brace}G{sub {mu}I}{r_brace}. Taking as fields reference system the diagonalized spin-1 sector, P, C, T and PCT symmetries are analyzed. They show that under this systemic model there are conservation laws driven for the parts and for the whole. It develops the meaning of whole-parity, field-parity and so on. However it is the whole symmetry that rules. This means that usually forbidden particles as pseudovector photons can be introduced through such whole abelian system. As result, one notices that the fields whole {l_brace}G{sub {mu}I}{r_brace} manifest a quanta diversity. It involves particles with different spins, masses and discrete quantum numbers under a same gauge symmetry. It says that without violating PCT symmetry different possibilities on discrete symmetries can be accommodated.

Chauca, J.; Doria, R. [CBPF, Rio de Janeiro (Brazil); Aprendanet, Petropolis, 25600 (Brazil)

2012-09-24T23:59:59.000Z

253

Geo-MHYDAS: A landscape discretization tool for distributed hydrological modeling of cultivated areas  

Science Conference Proceedings (OSTI)

The representation of landscape variabilities by means of an adequate landscape discretization is of major importance in distributed hydrological modeling. In this paper, we present Geo-MHYDAS, a landscape discretization tool that allows explicit representation ... Keywords: Cultivated catchment, Discretization, GIS, Hydrology, Landscape, Topology

P. Lagacherie; M. Rabotin; F. Colin; R. Moussa; M. Voltz

2010-08-01T23:59:59.000Z

254

A Bootstrap Method for Software Reliability Assessment Based on a Discretized NHPP Model  

Science Conference Proceedings (OSTI)

We discuss a bootstrap method for software reliability assessment based on a discretized no homogeneous Poisson process (NHPP) model. Ordinarily, model parameters of the discretized NHPP model are estimated by using the regression analysis based on the ... Keywords: Software reliability assessment, Discretized NHPP model, Regression analysis, Bootstrap method

Shinji Inoue; Shigeru Yamada

2012-11-01T23:59:59.000Z

255

Continuous vs. discrete models for the quantum harmonic oscillator and the hydrogen atom  

E-Print Network (OSTI)

The Kravchuk and Meixner polynomials of discrete variable are introduced for the discrete models of the harmonic oscillator and hydrogen atom. Starting from Rodrigues formula we construct raising and lowering operators, commutation and anticommutation relations. The physical properties of discrete models are figured out through the equivalence with the continuous models obtained by limit process.

M. Lorente

2004-01-15T23:59:59.000Z

256

Determining the adaptive decision zone of discrete lot sizing model with changes of total cost  

Science Conference Proceedings (OSTI)

The Economic Order Quantity (EOQ) zone is beneficial for giving some latitude in picking the lot sizes in a continuous time inventory problem, but it is not suitable for a discrete time inventory problem, the discrete lot sizing (DLS) problem. In this ... Keywords: Alternative solutions, Decision making, Discrete lot sizing, EOQ zone

Dong-Shang Chang; Fu-Chiao Chyr; Fu-Chiang Yang

2010-10-01T23:59:59.000Z

257

The quadratic-form identity for constructing the Hamiltonian structures of the discrete integrable systems  

Science Conference Proceedings (OSTI)

The quadratic-form identity is extended to the discrete version which can be used to construct the Hamiltonian structures of the discrete integrable systems associated with the Lie algebra possessing degenerate Killing forms. Especially, it can be used ... Keywords: Discrete quadratic-form identity, Hamiltonian structure, Integrable couplings, Liouville integrability, Toda hierarchy

Yuqin Yao; Jie Ji; Dengyuan Chen; Yunbo Zeng

2008-12-01T23:59:59.000Z

258

EMSL: Science: Atmospheric Aerosol Systems  

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

Atmospheric Aerosol Systems Atmospheric Aerosol Systems atmospheric logo Nighttime enhancement of nitrogen-containing organic compounds, or NOC Observed nighttime enhancement of nitrogen-containing organic compounds, or NOC, showed evidence of being formed by reactions that transform carbonyls into imines. The Atmospheric Aerosol Systems Science Theme focuses on understanding the chemistry, physics and molecular-scale dynamics of aerosols for model parameterization to improve the accuracy of climate model simulations and develop a predictive understanding of climate. By elucidating the role of natural and anthropogenic regional and global climate forcing mechanisms, EMSL can provide DOE and others with the ability to develop cost-effective strategies to monitor, control and mitigate them.

259

Discretization and Approximation Methods for Reinforcement Learning of Highly Reconfigurable Systems  

E-Print Network (OSTI)

There are a number of techniques that are used to solve reinforcement learning problems, but very few that have been developed for and tested on highly reconfigurable systems cast as reinforcement learning problems. Reconfigurable systems refers to a vehicle (air, ground, or water) or collection of vehicles that can change its geometrical features, i.e. shape or formation, to perform tasks that the vehicle could not otherwise accomplish. These systems tend to be optimized for several operating conditions, and then controllers are designed to reconfigure the system from one operating condition to another. Q-learning, an unsupervised episodic learning technique that solves the reinforcement learning problem, is an attractive control methodology for reconfigurable systems. It has been successfully applied to a myriad of control problems, and there are a number of variations that were developed to avoid or alleviate some limitations in earlier version of this approach. This dissertation describes the development of three modular enhancements to the Q-learning algorithm that solve some of the unique problems that arise when working with this class of systems, such as the complex interaction of reconfigurable parameters and computationally intensive models of the systems. A multi-resolution state-space discretization method is developed that adaptively rediscretizes the state-space by progressively finer grids around one or more distinct Regions Of Interest within the state or learning space. A genetic algorithm that autonomously selects the basis functions to be used in the approximation of the action-value function is applied periodically throughout the learning process. Policy comparison is added to monitor the state of the policy encoded in the action-value function to prevent unnecessary episodes at each level of discretization. This approach is validated on several problems including an inverted pendulum, reconfigurable airfoil, and reconfigurable wing. Results show that the multi-resolution state-space discretization method reduces the number of state-action pairs, often by an order of magnitude, required to achieve a specific goal and the policy comparison prevents unnecessary episodes once the policy has converged to a usable policy. Results also show that the genetic algorithm is a promising candidate for the selection of basis functions for function approximation of the action-value function.

Lampton, Amanda K.

2009-12-01T23:59:59.000Z

260

ELSEVIER AtmosphericResearch 38 (1995) 207-235 ATMOSPHERIC  

E-Print Network (OSTI)

ELSEVIER AtmosphericResearch 38 (1995) 207-235 ATMOSPHERIC RESEARCH On the parameterization of ice and water substance mixing ratio fields were only strongly altered by turning off the ice phase of these schemes includes ice processes. But in mid- latitudes and also in tropics the ice phase is an important

Moelders, Nicole

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


261

Atmospheric Chemistry and Physics  

E-Print Network (OSTI)

Abstract. A 3-D chemistry-transport model has been applied to the Mexico City metropolitan area to investigate the origin of elevated levels of non-fossil (NF) carbonaceous aerosols observed in this highly urbanized region. High time resolution measurements of the fine aerosol concentration and composition, and 12 or 24 h integrated 14 C measurements of aerosol modern carbon have been performed in and near Mexico City during the March 2006 MILAGRO field experiment. The non-fossil carbon fraction (fNF), which is lower than the measured modern fraction (fM) due to the elevated 14 C in the atmosphere caused by nuclear bomb testing, is estimated from the measured fM and the source-dependent information on modern carbon enrichment. The fNF contained in PM1 total carbon analyzed by a US team (f TC

unknown authors

2010-01-01T23:59:59.000Z

262

Atmospheric Corrosion Test Sites  

Science Conference Proceedings (OSTI)

Table 27   Some marine-atmospheric corrosion test sites around the world...Zealand Phia Marine 0.2 0.12 15.8 2.4 � � � � Greece Rafina Marine 0.2 0.12 13.6 1.0 � � � � Rhodes Marine 0.2 0.12 14.3 1.5 � � � � Netherlands Schagen Marine 2.4 1.5 17.0 2.0 � � � � Spain Almeria � 0.035 0.022 22.4 1.6 � � � � Cartagena � 0.050 0.031 5.2 1.9 � � � � La Coruña � 0.160 0.1 26.2 1.4...

263

A concurrent, multigroup, discrete ordinates model of neutron transport  

SciTech Connect

The authors present an algorithm for the concurrent solution of the linear system arising from a multigroup, discrete ordinates model of neutron transport. The target architectures consist of distributed memory computers ranging from workstation clusters to massively parallel computers. Based on an analysis of the memory requirement and floating point complexity of matrix-vector multiplication in the iterative solution of the linear system, the authors propose a data layout and communication strategy designed to achieve scalability with respect to all phase space variables. Numerical results are presented to demonstrate the performance of the algorithm on the nCUBE/2.

Dorr, M.R.; Still, C.H.

1993-10-22T23:59:59.000Z

264

Fourier transform method for imaging atmospheric Cherenkov telescopes  

E-Print Network (OSTI)

We propose Fourier transform (FT) method for processing images of extensive air showers (EAS) detected by imaging atmospheric Cherenkov telescopes (IACT) used in the very high energy (VHE) gamma-ray astronomy. The method is based on the discrete Fourier transforms (DFT) on compact Lie groups, and the use of continuous extension of the inverse discrete transforms to approximate the discrete EAS images by continuous EAS brightness distribution functions. Here we describe the FT-method in case of SU(3) group. It allows practical realization of the DFT technique for functions sampled on hexagonal symmetry grids. The proposed method can also be implemented in case of IACT cameras with grids of rectangular symmetry by using the DFT on the SU(2)xSU(2) group. The proposed FT-method is applied to the Monte-Carlo simulated bank of TeV proton and gamma-ray EAS images for a stand-alone telescope. Comparing between the FT-method and the currently used standard method shows that the FT technique allows a better and systematic enhancement of the gamma-ray signal. The relative difference between these two methods becomes more profound especially for `photon poor' images. It suggests that the EAS detection thresholds of IACTs could be effectively reduced with the use of FT technique. This prediction is further supported by a significant noise suppression capability of the method using simple low-pass filters in the image frequency domain. The FT-method allows very deep `tail' (and `height') image cuts, differentiation of images, operations in the image frequency domain, etc., that can be used for development of new effective parameters for the EAS image processing.

A. Atoyan; J. Patera; V. Sahakian; A. Akpherjanian

2004-09-15T23:59:59.000Z

265

From continuum Fokker-Planck models to discrete kinetic models  

E-Print Network (OSTI)

ABSTRACT Two theoretical formalisms are widely used in modeling mechanochemical systems such as protein motors: continuum Fokker-Planck models and discrete kinetic models. Both have advantages and disadvantages. Here we present a ‘‘finite volume’ ’ procedure to solve Fokker-Planck equations. The procedure relates the continuum equations to a discrete mechanochemical kinetic model while retaining many of the features of the continuum formulation. The resulting numerical algorithm is a generalization of the algorithm developed previously by Fricks, Wang, and Elston through relaxing the local linearization approximation of the potential functions, and a more accurate treatment of chemical transitions. The new algorithm dramatically reduces the number of numerical cells required for a prescribed accuracy. The kinetic models constructed in this fashion retain some features of the continuum potentials, so that the algorithm provides a systematic and consistent treatment of mechanical-chemical responses such as load-velocity relations, which are difficult to capture with a priori kinetic models. Several numerical examples are given to illustrate the performance of the method.

Jianhua Xing; Hongyun Wang; George Oster

2005-01-01T23:59:59.000Z

266

Discrete-element modeling of particulate aerosol flows  

Science Conference Proceedings (OSTI)

A multiple-time step computational approach is presented for efficient discrete-element modeling of aerosol flows containing adhesive solid particles. Adhesive aerosol particulates are found in numerous dust and smoke contamination problems, including smoke particle transport in the lungs, particle clogging of heat exchangers in construction vehicles, industrial nanoparticle transport and filtration systems, and dust fouling of electronic systems and MEMS components. Dust fouling of equipment is of particular concern for potential human occupation on dusty planets, such as Mars. The discrete-element method presented in this paper can be used for prediction of aggregate structure and breakup, for prediction of the effect of aggregate formation on the bulk fluid flow, and for prediction of the effects of small-scale flow features (e.g., due to surface roughness or MEMS patterning) on the aggregate formation. After presentation of the overall computational structure, the forces and torques acting on the particles resulting from fluid motion, particle-particle collision, and adhesion under van der Waals forces are reviewed. The effect of various parameters of normal collision and adhesion of two particles are examined in detail. The method is then used to examine aggregate formation and particle clogging in pipe and channel flow.

Marshall, J.S. [School of Engineering, University of Vermont, 33 Colchecter Avenue, Burlington, Vermont 05405 (United States)], E-mail: jeffm@cems.uvm.edu

2009-03-20T23:59:59.000Z

267

Atmospheric Radiation Measurement (ARM) Climate Research Facility and Atmospheric  

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

Atmospheric Radiation Measurement (ARM) Atmospheric Radiation Measurement (ARM) Climate Research Facility and Atmospheric System Research (ASR) Science and Infrastructure Steering Committee CHARTER June 2012 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not

268

A Method for Imposing Surface Stress and Heat Flux Conditions in Finite-Difference Models with Steep Terrain  

Science Conference Proceedings (OSTI)

A numerical implementation of the surface stress boundary condition is presented for finite-difference models in which the terrain slope and curvature cannot necessarily be considered small. The method involves reducing the discretized stress ...

C. C. Epifanio

2007-03-01T23:59:59.000Z

269

Mountain Forces and the Atmospheric Energy Budget  

Science Conference Proceedings (OSTI)

Although mountains are generally thought to exert forces on the atmosphere, the related transfers of energy between earth and atmosphere are not represented in standard energy equations of the atmosphere. It is shown that the axial rotation of the ...

Joseph Egger

2011-11-01T23:59:59.000Z

270

Hybrid fluid/kinetic modeling of Pluto's escaping atmosphere  

E-Print Network (OSTI)

Predicting the rate of escape and thermal structure of Pluto's upper atmosphere in preparation for the New Horizons Spacecraft encounter in 2015 is important for planning and interpreting the expected measurements. Having a moderate Jeans parameter Pluto's atmosphere does not fit the classic definition of Jeans escape for light species escaping from the terrestrial planets, nor does it fit the hydrodynamic outflow from comets and certain exoplanets. It has been proposed for some time that Pluto lies in the region of slow-hydrodynamic escape. Using a hybrid fluid/molecular-kinetic model, we previously demonstrated the typical implementation of this model fails to correctly describe the appropriate temperature structure for the upper atmosphere for solar minimum conditions. Here we used a time-dependent solver to allow us to extend those simulations to higher heating rates and we examined fluid models in which Jeans-like escape expressions are used for the upper boundary conditions. We compare these to our hybr...

Erwin, Justin T; Johnson, Robert E

2012-01-01T23:59:59.000Z

271

Baiu rainband termination in atmospheric and atmosphere-ocean models  

Science Conference Proceedings (OSTI)

Baiu rainband is a summer rainband stretching from eastern China through Japan towards the Northwest Pacific. The climatological termination of the Baiu rainband is investigated using Japanese 25-year ReAnalysis (JRA25), a stand-alone atmospheric ...

Akira Kuwano-Yoshida; Bunmei Taguchi; Shang-Ping Xie

272

Krypton-85 in the atmosphere  

E-Print Network (OSTI)

Measurement results are presented on 85Kr content in the atmosphere over the European part of Russia in 1971-1995 based on the analysis of the commercial krypton, which is separated from air by industrial plants. Our results are by 15 per cent lower then 85Kr activites observed over West Europe. According our prediction by 2030 85Kr content in the atmosphere over Europe will amount to 1,5-3 Bq in m3 air. Average 85Kr release to the atmosphere from regeneration of spent nuclear fuel (SNF) is estimated, some 180 TBq per a ton SNF. It is advisable to recommence monitoring of 85Kr content within Russia.

A. T. Korsakov; E. G. Tertyshnik

2013-07-09T23:59:59.000Z

273

Krypton-85 in the atmosphere  

E-Print Network (OSTI)

Measurement results are presented on 85Kr content in the atmosphere over the European part of Russia in 1971-1995 based on the analysis of the commercial krypton, which is separated from air by industrial plants. Our results are by 15 per cent lower then 85Kr activites observed over West Europe. According our prediction by 2030 85Kr content in the atmosphere over Europe will amount to 1,5-3 Bq in m3 air. Average 85Kr release to the atmosphere from regeneration of spent nuclear fuel (SNF) is estimated, some 180 TBq per a ton SNF. It is advisable to recommence monitoring of 85Kr content within Russia.

Korsakov, A T

2013-01-01T23:59:59.000Z

274

Continuum discretization methods in a composite-particle scattering off a nucleus: the benchmark calculations  

E-Print Network (OSTI)

The direct comparison of two different continuum discretization methods towards the solution of a composite particle scattering off a nucleus is presented. The first approach -- the Continumm-Discretized Coupled Channel method -- is based on the differential equation formalism, while the second one -- the Wave-Packet Continuum Discretization method -- uses the integral equation formulation for the composite-particle scattering problem. As benchmark calculations we have chosen the deuteron off \

O. A. Rubtsova; V. I. Kukulin; A. M. Moro

2008-06-13T23:59:59.000Z

275

Fractured reservoir discrete feature network technologies. Final report, March 7, 1996 to September 30, 1998  

Science Conference Proceedings (OSTI)

This report summarizes research conducted for the Fractured Reservoir Discrete Feature Network Technologies Project. The five areas studied are development of hierarchical fracture models; fractured reservoir compartmentalization, block size, and tributary volume analysis; development and demonstration of fractured reservoir discrete feature data analysis tools; development of tools for data integration and reservoir simulation through application of discrete feature network technologies for tertiary oil production; quantitative evaluation of the economic value of this analysis approach.

Dershowitz, William S.; Einstein, Herbert H.; LaPoint, Paul R.; Eiben, Thorsten; Wadleigh, Eugene; Ivanova, Violeta

1998-12-01T23:59:59.000Z

276

Space-time discontinuous Galerkin discretization of rotating shallow water equations  

Science Conference Proceedings (OSTI)

A space-time discontinuous Galerkin (DG) discretization is presented for the (rotating) shallow water equations over varying topography. We formulate the space-time DG finite element discretization in an efficient and conservative discretization. The ... Keywords: 35Q35, 65N30, 75S05, 76B15, 76M10, Bores, Discontinuous Galerkin methods, Finite element methods, Moving grid, Numerical dissipation, Potential vorticity, Shallow water equations

V. R. Ambati; O. Bokhove

2007-08-01T23:59:59.000Z

277

Glossary Term - Composition of the Earth's Atmosphere  

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

the Earth's Atmosphere Source: Definition of the U.S. Standard Atmosphere (1976) CRC Handbook of Chemistry and Physics, 77th Edition Gas Formula Abundance percent by volume...

278

A Computational Thermodynamic Analysis of Atmospheric ...  

Science Conference Proceedings (OSTI)

Feb 1, 2001 ... The vacuum atmosphere is typically 0.1 atm. However, the vacuum atmosphere creates two major problems: air leakage and batch operation to ...

279

Adjustment of the Remote Tropical Climate to El Nińo Conditions  

Science Conference Proceedings (OSTI)

The adjustment of the tropical climate outside the Pacific (the “remote Tropics”) to the abrupt onset of El Nińo conditions is examined in a tropical atmosphere model that assumes simplified vertical structure and quasi-equilibrium (QE) ...

Benjamin R. Lintner; John C. H. Chiang

2007-06-01T23:59:59.000Z

280

Investigation of Surface Duct Conditions over Istanbul, Turkey  

Science Conference Proceedings (OSTI)

A comprehensive examination of 2 yr of radiosonde data to determine the surface duct conditions over Istanbul (4°N, 29°E), Turkey, was made. The refractivity of the atmosphere is a function of air temperature and water vapor pressure. Any ...

?Sibel Mentes; Zerefsan Kaymaz

2007-03-01T23:59:59.000Z

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


281

DISCRETE-FREQUENCY AND BROADBAND NOISE RADIATION FROM DIESEL ENGINE COOLING FANS.  

E-Print Network (OSTI)

??This effort focuses on measuring and predicting the discrete-frequency and broadband noise radiated by diesel engine cooling fans. Unsteady forces developed by the interaction of… (more)

Kim, Geon-Seok

2007-01-01T23:59:59.000Z

282

An Evaluation of Bulk Ri-Based Surface Layer Flux Formulas for Stable and Very Stable Conditions with Intermittent Turbulence  

Science Conference Proceedings (OSTI)

High-rate near-surface overnight atmospheric data taken during the Cooperative Atmosphere–Surface Exchange Study-1999 (CASES-99) is used to quantify the representativeness of surface layer formulations under statically stable conditions. Combined ...

Gregory S. Poulos; Sean P. Burns

2003-10-01T23:59:59.000Z

283

The Workshop in Atmospheric Predictability  

Science Conference Proceedings (OSTI)

A workshop on the subject of atmospheric predictability was held during 23-25 April 2001 at the Naval Postgraduate School in Monterey, California. Of primary concern was the nature of forecast uncertainty due to initial conditionuncertainty of ...

Ronald M. Errico; Rolf Langland; David P. Baumhefner

2002-09-01T23:59:59.000Z

284

(Chemistry of the global atmosphere)  

SciTech Connect

The traveler attended the conference The Chemistry of the Global Atmosphere,'' and presented a paper on the anthropogenic emission of carbon dioxide (CO{sub 2}) to the atmosphere. The conference included meetings of the International Global Atmospheric Chemistry (IGAC) programme, a core project of the International Geosphere/Biosphere Programme (IGBP) and the traveler participated in meetings on the IGAC project Development of Global Emissions Inventories'' and agreed to coordinate the working group on CO{sub 2}. Papers presented at the conference focused on the latest developments in analytical methods, modeling and understanding of atmospheric CO{sub 2}, CO, CH{sub 4}, N{sub 2}O, SO{sub 2}, NO{sub x}, NMHCs, CFCs, and aerosols.

Marland, G.

1990-09-27T23:59:59.000Z

285

Automated Measurements of Atmospheric Visibility  

Science Conference Proceedings (OSTI)

The concept of using a solid-state, linear-array imaging device coupled with computerized scene analysis and display to measure daytime atmospheric visibility is described. Computer software is implemented for routine conversion of observed ...

W. Viezee; W. E. Evans

1983-08-01T23:59:59.000Z

286

The Navy's Operational Atmospheric Analysis  

Science Conference Proceedings (OSTI)

In January of 1988, significant upgrades were made to the Navy Operational Global Atmospheric Prediction System (NOGAPS). Among these improvements was the implementation of a multivariate optimum interpolation analysis scheme. Since that time, ...

James S. Goerss; Patricia A. Phoebus

1992-06-01T23:59:59.000Z

287

Stochastic Simulation of Atmospheric Trajectories  

Science Conference Proceedings (OSTI)

Methods are presented for generating an ensemble of synthetic atmospheric trajectories. These include methods for a set of independent trajectories, and methods for a correlated set of sequential trajectories. The models incorporate first-order ...

Mitchell J. Small; Perry J. Samson

1983-02-01T23:59:59.000Z

288

Atmospheric Water Vapor over China  

Science Conference Proceedings (OSTI)

Chinese radiosonde data from 1970 to 1990 are relatively homogeneous in time and are used to examine the climatology, trends, and variability of China’s atmospheric water vapor content. The climatological distribution of precipitable water (PW) ...

Panmao Zhai; Robert E. Eskridge

1997-10-01T23:59:59.000Z

289

A discrete variable representation for electron-hydrogen atom scattering  

DOE Green Energy (OSTI)

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

Gaucher, L.F.

1994-08-01T23:59:59.000Z

290

Compression algorithm for discrete light-cone quantization  

E-Print Network (OSTI)

We adapt the compression algorithm of Weinstein, Auerbach, and Chandra from eigenvectors of spin lattice Hamiltonians to eigenvectors of light-front field-theoretic Hamiltonians. The latter are approximated by the standard discrete light-cone quantization technique, which provides a matrix representation of the Hamiltonian eigenvalue problem. The eigenvectors are represented as singular value decompositions of two-dimensional arrays, indexed by transverse and longitudinal momenta, and compressed by truncation of the decomposition. The Hamiltonian is represented by a rank-four tensor that is decomposed as a sum of contributions factorized into direct products of separate matrices for transverse and longitudinal interactions. The algorithm is applied to a model theory, to illustrate its use.

Xiao Pu; Sophia S. Chabysheva; John R. Hiller

2013-08-22T23:59:59.000Z

291

Public key Steganography Using Discrete Cross-Coupled Chaotic Maps  

E-Print Network (OSTI)

By cross-coupling two logistic maps a novel method is proposed for the public key steganography in JPEG image. Chaotic maps entail high complexity in the used algorithm for embedding secret data in a medium. In this paper, discrete cross- coupled chaotic maps are used to specifying the location of the different parts of the secret data in the image. Modifying JPEG format during compressing and decompressing, and also using public key enhanced difficulty of the algorithm. Simulation results show that in addition to excessive capacity, this method has high robustness and resistance against hackers and can be applicable in secret communication. Also the PSNR value is high compared to the other works.

Sodeif Ahadpour; Mahdiyeh Majidpour; Yaser Sadra

2012-11-01T23:59:59.000Z

292

Derivation of new 3D discrete ordinate equations  

Science Conference Proceedings (OSTI)

The Sn equations have been the workhorse of deterministic radiation transport calculations for many years. Here we derive two new angular discretizations of the 3D transport equation. The first set of equations, derived using Lagrange interpolation and collocation, retains the classical Sn structure, with the main difference being how the scattering source is calculated. Because of the formal similarity with the classical S n equations, it should be possible to modify existing computer codes to take advantage of the new formulation. In addition, the new S n-like equations correctly capture delta function scattering. The second set of equations, derived using a Galerkin technique, does not retain the classical Sn structure because the streaming term is not diagonal. However, these equations can be cast into a form similar to existing methods developed to reduce ray effects. Numerical investigation of both sets of equations is under way. (authors)

Ahrens, C. D. [Colorado School of Mines, Dept. of Applied Mathematics and Statistics, Program in Nuclear Science and Engineering, Golden, CO 80401-1887 (United States)

2012-07-01T23:59:59.000Z

293

Discrete pulse modulation strategies for high-frequency inverter systems  

SciTech Connect

High-performance high-frequency inverter systems for UPS applications represent a demanding application that cannot be easily realized using conventional hard-switched PWM inverter topologies. Adoption of typical soft-switched inverters such as the resonant dc link inverter require the use of discrete pulse modulation strategies. New controller structures are necessary to cope with stringent voltage regulation and distortion constraints in the presence of unbalanced and nonlinear loads. This paper presents a controller that utilizes load current feed-forward strategy with a cost function current regulator to achieve excellent transient performance characteristics. Voltage regulation is ensured using a synchronous frame regulator. Detailed simulation and experimental results verifying the concepts are presented. Although this paper focuses on soft-switching inverters, the control concepts can be applied to conventional hard-switching inverters as well.

Venkataramanan, G. (Montana State Univ., Bozeman, MT (United States). Dept. of Electrical Engineering); Divan, D.M. (Univ. of Wisconsin, Madison, WI (United States). Dept. of Electrical and Computer Engineering); Jahns, T.M. (General Electric Co., Schenectady, NY (United States))

1993-07-01T23:59:59.000Z

294

International Journal of Computers and Applications, Vol. 31, No. 2, 2009 PASSIVE ATMOSPHERIC DIFFUSION  

E-Print Network (OSTI)

such as atmospheric gas dispersion by industrial accidents or processes are generally predicted with Gaussian plumes simplicity, the Gaussian dispersion model is often used for predicting the progression of atmospheric gas of passive dispersion, initial conditions of gas emissions are often addressed differently, as various gases

Beauchemin, Steven S.

295

AN ANALYTIC RADIATIVE-CONVECTIVE MODEL FOR PLANETARY ATMOSPHERES  

Science Conference Proceedings (OSTI)

We present an analytic one-dimensional radiative-convective model of the thermal structure of planetary atmospheres. Our model assumes that thermal radiative transfer is gray and can be represented by the two-stream approximation. Model atmospheres are assumed to be in hydrostatic equilibrium, with a power-law scaling between the atmospheric pressure and the gray thermal optical depth. The convective portions of our models are taken to follow adiabats that account for condensation of volatiles through a scaling parameter to the dry adiabat. By combining these assumptions, we produce simple, analytic expressions that allow calculations of the atmospheric-pressure-temperature profile, as well as expressions for the profiles of thermal radiative flux and convective flux. We explore the general behaviors of our model. These investigations encompass (1) worlds where atmospheric attenuation of sunlight is weak, which we show tend to have relatively high radiative-convective boundaries; (2) worlds with some attenuation of sunlight throughout the atmosphere, which we show can produce either shallow or deep radiative-convective boundaries, depending on the strength of sunlight attenuation; and (3) strongly irradiated giant planets (including hot Jupiters), where we explore the conditions under which these worlds acquire detached convective regions in their mid-tropospheres. Finally, we validate our model and demonstrate its utility through comparisons to the average observed thermal structure of Venus, Jupiter, and Titan, and by comparing computed flux profiles to more complex models.

Robinson, Tyler D. [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195-1580 (United States); Catling, David C., E-mail: robinson@astro.washington.edu [Department of Earth and Space Sciences, University of Washington, Box 351310, Seattle, WA 98195-1310 (United States)

2012-09-20T23:59:59.000Z

296

A Combined Local and Nonlocal Closure Model for the Atmospheric Boundary Layer. Part I: Model Description and Testing  

Science Conference Proceedings (OSTI)

The modeling of the atmospheric boundary layer during convective conditions has long been a major source of uncertainty in the numerical modeling of meteorological conditions and air quality. Much of the difficulty stems from the large range of ...

Jonathan E. Pleim

2007-09-01T23:59:59.000Z

297

A Refined Calibration Procedure of Two-Channel Sun Photometers to Measure Atmospheric Precipitable Water at Various Antarctic Sites  

Science Conference Proceedings (OSTI)

Two-channel sun photometers can be easily employed at Antarctic sites, where harsh environmental conditions prevail, to carry out measurements of precipitable water W. In the very dry air conditions observed in the Antarctic atmosphere, water ...

Claudio Tomasi; Boyan Petkov; Elena Benedetti; Luca Valenziano; Angelo Lupi; Vito Vitale; Ubaldo Bonafé

2008-02-01T23:59:59.000Z

298

Discrete magic angle turning system, apparatus, and process for in situ magnetic resonance spectroscopy and imaging  

DOE Patents (OSTI)

Described are a "Discrete Magic Angle Turning" (DMAT) system, devices, and processes that combine advantages of both magic angle turning (MAT) and magic angle hopping (MAH) suitable, e.g., for in situ magnetic resonance spectroscopy and/or imaging. In an exemplary system, device, and process, samples are rotated in a clockwise direction followed by an anticlockwise direction of exactly the same amount. Rotation proceeds through an angle that is typically greater than about 240 degrees but less than or equal to about 360 degrees at constant speed for a time applicable to the evolution dimension. Back and forth rotation can be synchronized and repeated with a special radio frequency (RF) pulse sequence to produce an isotropic-anisotropic shift 2D correlation spectrum. The design permits tubes to be inserted into the sample container without introducing plumbing interferences, further allowing control over such conditions as temperature, pressure, flow conditions, and feed compositions, thus permitting true in-situ investigations to be carried out.

Hu, Jian Zhi (Richland, WA); Sears, Jr., Jesse A. (Kennewick, WA); Hoyt, David W. (Richland, WA); Wind, Robert A. (Kennewick, WA)

2009-05-19T23:59:59.000Z

299

Atmospheric Condensation Potential of Windows in Hot, Humid Climates  

E-Print Network (OSTI)

In hot, humid climates, the internal surfaces of windows in air-conditioned buildings are in contact with relatively colder air. Meanwhile, the external surfaces are exposed to hot humid atmospheric air. This hygro-thermal condition may cause frequent atmospheric condensation on external surfaces of windows when their surface temperature drops below the dew point temperature of the hot humid air. To date, external surface condensation on windows has been given relatively much less importance than their internal surface condensation. In addition, the thermal analysis of windows in hot humid climates has always been performed in the absence of condensation. Under moderate air temperature and humidity conditions, such practice is acceplable. However, when windows experience atmospheric condensation on their external surfaces, the effect of condensation on window energy loss needs to be examined. In this paper, the external condensation process is analyzed and the atmospheric water vapor mass condensation rate has been obtained by utilizing a simplified transient uni-dimensional finite difference model. The results show that this model has enhanced the assessment of the potential for atmospheric condensation on windows in hot, humid climates and in predicting the amount of condensation expected, as well as the associated energy loss for given thermal and moisture conditions. The numerical computation of the model is able to account for condensation and its impact on the temperature gradient across the window. Thermal analysis of both single and insulated double-glazed windows under condensation conditions is presented. The work also includes the computational procedure used and the results or a case study demonstrating the model's capabilities.

El Diasty, R.; Budaiwi, I.

1992-05-01T23:59:59.000Z

300

Atmospheric Radiation Measurement Program Science Plan  

SciTech Connect

The Atmospheric Radiation Measurement (ARM) Program has matured into one of the key programs in the U.S. Climate Change Science Program. The ARM Program has achieved considerable scientific success in a broad range of activities, including site and instrument development, atmospheric radiative transfer, aerosol science, determination of cloud properties, cloud modeling, and cloud parameterization testing and development. The focus of ARM science has naturally shifted during the last few years to an increasing emphasis on modeling and parameterization studies to take advantage of the long time series of data now available. During the next 5 years, the principal focus of the ARM science program will be to: Maintain the data record at the fixed ARM sites for at least the next five years. Improve significantly our understanding of and ability to parameterize the 3-D cloud-radiation problem at scales from the local atmospheric column to the global climate model (GCM) grid square. Continue developing techniques to retrieve the properties of all clouds, with a special focus on ice clouds and mixed-phase clouds. Develop a focused research effort on the indirect aerosol problem that spans observations, physical models, and climate model parameterizations. Implement and evaluate an operational methodology to calculate broad-band heating rates in the atmospheric columns at the ARM sites. Develop and implement methodologies to use ARM data more effectively to test atmospheric models, both at the cloud-resolving model scale and the GCM scale. Use these methodologies to diagnose cloud parameterization performance and then refine these parameterizations to improve the accuracy of climate model simulations. In addition, the ARM Program is actively developing a new ARM Mobile Facility (AMF) that will be available for short deployments (several months to a year or more) in climatically important regions. The AMF will have much of the same instrumentation as the remote facilities at ARM's Tropical Western Pacific and the North Slope of Alaska sites. Over time, this new facility will extend ARM science to a much broader range of conditions for model testing.

Ackerman, T

2004-10-31T23:59:59.000Z

Note: This page contains sample records for the topic "discrete atmospheric conditions" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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301

Anomalous North Pacific Atmospheric Circulation and Large Winter Floods in the Southwestern United States  

Science Conference Proceedings (OSTI)

Specific anomalous atmospheric circulation conditions over the North Pacific are conducive to the occurrence of the largest winter floods (?10-yr return period) on rivers in six hydroclimatic subregions of Arizona and southern Utah, Nevada, and ...

Lisa L. Ely; Yehouda Enzel; Daniel R. Cayan

1994-06-01T23:59:59.000Z

302

Tracking Atmospheric Instabilities with the Kalman Filter. Part II: Two-Layer Results  

Science Conference Proceedings (OSTI)

Sequential data assimilation schemes approaching true optimality for sizable atmospheric models are becoming a reality. The behavior of the Kalman filter (KF) under difficult conditions needs therefore to be understood. In this two-part paper the ...

Michael Ghil; Ricardo Todling

1996-10-01T23:59:59.000Z

303

A 2 Degree of Freedom Dynamical System for Interdecadal Oscillations of the Ocean–Atmosphere  

Science Conference Proceedings (OSTI)

A four-box model of the ocean–atmosphere is constructed that exhibits self-sustained oscillations in the regime of decadal to interdecadal periods found in oceanic general circulation models under certain boundary conditions. The oscillations are ...

Alain Colin de Verdičre; Thierry Huck

2000-08-01T23:59:59.000Z

304

Atmospheric Dispersion from Elevated Sources in an Urban Area: Comparison between Tracer Experiments and Model Calculations  

Science Conference Proceedings (OSTI)

Atmospheric dispersion experiments were carried out in the Copenhagen area under neutral and unstable conditions. The tracer sulphurhexafluoride was released without buoyancy from a tower at a height of 115 m and then collected at ground-level ...

Sven-Erik Gryning; Erik Lyck

1984-04-01T23:59:59.000Z

305

Atmospheric Response to Zonal Variations in Midlatitude SST: Transient and Stationary Eddies and Their Feedback  

Science Conference Proceedings (OSTI)

Midwinter storm track response to zonal variations in midlatitude sea surface temperatures (SSTs) has been investigated using an atmospheric general circulation model under aquaplanet and perpetual-January conditions. Zonal wavenumber-1 SST ...

Masaru Inatsu; Hitoshi Mukougawa; Shang-Ping Xie

2003-10-01T23:59:59.000Z

306

Mount Kenya Global Atmosphere Watch Station (MKN): Installation and Meteorological Characterization  

Science Conference Proceedings (OSTI)

The meteorological conditions at the Mount Kenya (station identifier MKN) tropical Global Atmosphere Watch Programme station are described. Like other stations in mountainous terrain, the site experiences thermally induced wind systems that ...

Stephan Henne; Wolfgang Junkermann; Josiah M. Kariuki; John Aseyo; Jörg Klausen

2008-11-01T23:59:59.000Z

307

Stability and Variability in a Coupled Ocean–Atmosphere Climate Model: Results of 100-year Simulations  

Science Conference Proceedings (OSTI)

Two 100-year seasonal simulators, one performed with a low resolution atmospheric general circulation model (GCM) coupled to a mixed-layer ocean formulation and the other made with the GCM forced by prescribed ocean conditions, are compared to ...

David D. Houghton; Robert G. Gallimore; Linda M. Keller

1991-06-01T23:59:59.000Z

308

EPIC2001 and the Coupled Ocean–Atmosphere System of the Tropical East Pacific  

Science Conference Proceedings (OSTI)

Coupled global ocean–atmosphere models currently do a poor job of predicting conditions in the tropical east Pacific, and have a particularly hard time reproducing the annual cycle in this region. This poor performance is probably due to the ...

David J. Raymond; Steven K. Esbensen; Clayton Paulson; Michael Gregg; Christopher S. Bretherton; Walter A. Petersen; Robert Cifelli; Lynn K. Shay; Carter Ohlmann; Paquita Zuidema

2004-09-01T23:59:59.000Z

309

On the Maximum Exospheric Temperature of Hydrogen-Dominated Planetary Atmospheres  

Science Conference Proceedings (OSTI)

It is shown that under static conditions the maximum temperature attainable in the exospheres of hydrogen-dominated planetary atmospheres is of order 105 K when gravitational separation between hydrogen and other elements has occurred, and 104 K ...

G. P. Horedt

1982-06-01T23:59:59.000Z

310

A Green Planet versus a Desert World: Estimating the Effect of Vegetation Extremes on the Atmosphere  

Science Conference Proceedings (OSTI)

The effect of vegetation extremes on the general circulation is estimated by two atmospheric GCM simulations using global desert and forest boundary conditions over land. The difference between the climates of a “green planet” and a “desert world”...

Klaus Fraedrich; Axel Kleidon; Frank Lunkeit

1999-10-01T23:59:59.000Z

311

Intermittency and the Organization of Turbulence in the Near-Neutral Marine Atmospheric Boundary Layer  

Science Conference Proceedings (OSTI)

Aircraft data from the JASIN Experiment have been used to examine the role that intermittency plays in turbulent transfer in the near-neutral marine atmospheric boundary layer. Conditional sampling, using the time-varying dissipation rate as an ...

William J. Shaw; Joost A. Businger

1985-12-01T23:59:59.000Z

312

The Layered Structure of the Winter Atmospheric Boundary Layer in the Interior of Alaska  

Science Conference Proceedings (OSTI)

The high-latitude winter atmospheric boundary layer of interior Alaska continually exhibits a complex layered structure as a result of extreme meteorological conditions. In this paper the occurrence of elevated inversions (EI), surface-based ...

John A. Mayfield; Gilberto J. Fochesatto

2013-04-01T23:59:59.000Z

313

A Total Turbulent Energy Closure Model for Neutrally and Stably Stratified Atmospheric Boundary Layers  

Science Conference Proceedings (OSTI)

This paper presents a turbulence closure for neutral and stratified atmospheric conditions. The closure is based on the concept of the total turbulent energy. The total turbulent energy is the sum of the turbulent kinetic energy and turbulent ...

Thorsten Mauritsen; Gunilla Svensson; Sergej S. Zilitinkevich; Igor Esau; Leif Enger; Branko Grisogono

2007-11-01T23:59:59.000Z

314

Climate Simulation for 125 kyr BP with a Coupled Ocean–Atmosphere General Circulation Model  

Science Conference Proceedings (OSTI)

The ECHAM-1 T21/LSG coupled ocean–atmosphere general circulation model (GCM) is used to simulate climatic conditions at the last interglacial maximum (Eemian, 125 kyr BP). The results reflect the expected surface temperature changes (with respect ...

Marisa Montoya; Hans von Storch; Thomas J. Crowley

2000-03-01T23:59:59.000Z

315

PASS: A Portable Atmospheric Sampling System for Chemical Studies in the Marine Troposphere  

Science Conference Proceedings (OSTI)

The measurement of many trace substances in the remote marine atmosphere requires that they be collected under controlled conditions and that meteorological and other data concerning these measurements be available to the experimenter. A Portable ...

George Schwartze; Robert Boldi; Timothy Wasco; Robert Duce

1988-08-01T23:59:59.000Z

316

An Algorithm for Lidar Mapping of Aerosol Concentrations in a Varying Atmospheric Background Density  

Science Conference Proceedings (OSTI)

An algorithm for the determination of the number density profiles of a specific aerosol as a function of time and space is developed and discussed. The algorithm is applicable to atmospheric conditions in which a varying density particulate ...

Moshe Kleiman; Smadar Egert; Ariel Cohen

1986-12-01T23:59:59.000Z

317

On the Analytical Solutions of Flux-Profile Relationships for the Atmospheric Surface Layer  

Science Conference Proceedings (OSTI)

Analytical solutions Of surface layer similarity equations are presented for the nondimensional profile functional forms suggested by Businger et al. For stable atmospheric conditions, exact analytical solutions of the Monin-Obukhoy stability ...

Daewon W. Byun

1990-07-01T23:59:59.000Z

318

Contrasting Regional Responses to Increasing Leaf-Level Atmospheric Carbon Dioxide over Australia  

Science Conference Proceedings (OSTI)

Using a coupled atmosphere–land surface model, simulations were conducted to characterize the regional climate changes that result from the response of stomates to increases in leaf-level carbon dioxide (CO2) under differing conditions of ...

Faye T. Cruz; Andrew J. Pitman; John L. McGregor; Jason P. Evans

2010-04-01T23:59:59.000Z

319

Initialization of Soil-Water Content in Regional-Scale Atmospheric Prediction Models  

Science Conference Proceedings (OSTI)

The purpose of this study is to demonstrate the feasibility of determining the soil-water content fields required as initial conditions for land surface components within atmospheric prediction models. This is done using a model of the hydrologic ...

Christopher B. Smith; Mercedes N. Lakhtakia; William J. Capehart; Toby N. Carlson

1994-04-01T23:59:59.000Z

320

Extreme Cold Winter Temperatures in Europe under the Influence of North Atlantic Atmospheric Blocking  

Science Conference Proceedings (OSTI)

North Atlantic atmospheric blocking conditions explain part of the winter climate variability in Europe, being associated with anomalous cold winter temperatures. In this study, the generalized extreme value (GEV) distribution is fitted to monthly ...

Jana Sillmann; Mischa Croci-Maspoli; Malaak Kallache; Richard W. Katz

2011-11-01T23:59:59.000Z

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


321

Comparison of Infrared Atmospheric Brightness Temperatures Measured by a Fourier Transform Spectrometer and a Filter Radiometer  

Science Conference Proceedings (OSTI)

Increased interest in using atmospheric brightness temperature measurements from simple infrared radiometers combined with radars and lidars has prompted the investigation of their accuracy for various sky conditions. In comparisons of ...

Joseph A. Shaw; Jack B. Snider; James H. Churnside; Mark D. Jacobson

1995-10-01T23:59:59.000Z

322

The application of discrete event simulation and system dynamics in the logistics and supply chain context  

Science Conference Proceedings (OSTI)

Discrete event simulation (DES) and system dynamics (SD) are two modelling approaches widely used as decision support tools in logistics and supply chain management (LSCM). A widely held belief exists that SD is mostly used to model problems at a strategic ... Keywords: Comparison of methods, Discrete-event simulation, Logistics and supply chain management, Simulation modelling, System dynamics

Antuela A. Tako; Stewart Robinson

2012-03-01T23:59:59.000Z

323

The Discrete Event Concept as a Paradigm for the “Perception-Based Diagnosis” of Sachem  

Science Conference Proceedings (OSTI)

Sachem is an extensive large-scale real time knowledge-based system designed to monitor and diagnose blast furnaces. This paper aims at illustrating the way the concept of discrete event allowed the definition of a “perception-based diagnosis” ... Keywords: artificial intelligence, discrete event systems, fault diagnosis, knowledge-based systems, monitored control systems

Marc Le Goc; Claudia Frydman

2004-06-01T23:59:59.000Z

324

Rapid gravity and gravity gradiometry terrain corrections via an adaptive quadtree mesh discretization  

E-Print Network (OSTI)

Rapid gravity and gravity gradiometry terrain corrections via an adaptive quadtree mesh discretization Kristofer Davis1,2 M. Andy Kass1 Yaoguo Li1 1 Center for Gravity, Electrical, and Magnetic Studies of gravity gradiometry surveys utilising an adaptive quadtree mesh discretization. The data- and terrain

325

Utilization of Discretization method on the diagnosis of optic nerve disease  

Science Conference Proceedings (OSTI)

The optic nerve disease is an important disease that appears commonly in public. In this paper, we propose a hybrid diagnostic system based on discretization (quantization) method and classification algorithms including C4.5 decision tree classifier, ... Keywords: Artificial neural network, C4.5 decision tree classifier, Discretization method, Hybrid systems, Least square support vector machine, Optic nerve disease, VEP signals

Kemal Polat; Sad?k Kara; Ay?egül Güven; Salih Güne?

2008-09-01T23:59:59.000Z

326

Non-Abelian Groups in Optimization of Decision Diagrams Representations of Discrete Functions  

Science Conference Proceedings (OSTI)

This paper is devoted to the reduction of decision diagram (DD) representations of discrete functions by using the non-Abelian groups and Fourier DDs on these groups. The number of levels in a DD can be reduced through decomposition of the domain group ... Keywords: Fourier transform, decision diagrams, discrete functions, non-Abelian groups

Radomir S. Stankovi?

2001-05-01T23:59:59.000Z

327

Discrete spectrum distribution of the Landau Operator Perturbed by an Expanding Electric Potential  

E-Print Network (OSTI)

Under a perturbation by a decaying electric potential, the Landau Hamiltonian acquires some discrete eigenvalues between the Landau levels. We study the perturbation by an "expanding" electric potential $V(t^{-1}x)$, $t>0$, and derive a quasi-classical formula for the counting function of the discrete spectrum as $t\\to \\infty$.

Grigori Rozenblum; Alexander V. Sobolev

2007-11-14T23:59:59.000Z

328

Discrete spectrum distribution of the Landau Operator Perturbed by an Expanding Electric Potential  

E-Print Network (OSTI)

Under a perturbation by a decaying electric potential, the Landau Hamiltonian acquires some discrete eigenvalues between the Landau levels. We study the perturbation by an "expanding" electric potential $V(t^{-1}x)$, $t>0$, and derive a quasi-classical formula for the counting function of the discrete spectrum as $t\\to \\infty$.

Rozenblum, Grigori

2007-01-01T23:59:59.000Z

329

Verification of initial-state opacity in security applications of discrete event systems  

Science Conference Proceedings (OSTI)

In this paper, we formulate and analyze methodologies for verifying the notion of initial-state opacity in discrete event systems that are modeled as non-deterministic finite automata with partial observation on their transitions. A system is initial-state ... Keywords: Discrete event system, Formal methods in security analysis, Initial state estimation, Initial state estimator, Tracking in sensor network

Anooshiravan Saboori, Christoforos N. Hadjicostis

2013-10-01T23:59:59.000Z

330

Translation-invariant two-dimensional discrete wavelet transform on graphics processing units  

Science Conference Proceedings (OSTI)

The Discrete Wavelet Transform (DWT) is used in several signal and image processing applications. Due to the computational expense various approaches have been proposed. One approach is using graphics processing units (GPUs) as stream processors to speed ... Keywords: GPU, algorithme ŕ trous, image processing, parallel discrete wavelet transform, shader

Dietmar Wippig; Bernd Klauer

2010-11-01T23:59:59.000Z

331

Discrete event modeling through a multi-formalism approach, from a user-oriented perspective  

Science Conference Proceedings (OSTI)

The hierarchy of formalism presented in this paper is part of an on going work in the development of a broad hierarchy of DEVS based formalisms. We introduce a hierarchy of formalisms with different temporal restrictions targeted to the discrete event ... Keywords: DEVS modeling methodology, discrete event modeling, multi-formalisms approach

Hernán P. Dacharry; Norbert Giambiasi

2007-03-01T23:59:59.000Z

332

Discrete Differential Forms for $(1+1)$-Dimensional Cosmological Space-Times  

Science Conference Proceedings (OSTI)

In this article we describe applications of the numerical method of discrete differential forms in computational general relativity (GR). In particular, we consider the initial value problem for vacuum space-times that admit plane gravitational waves. ... Keywords: discrete differential forms, polarized gowdy, translationally symmetric space-time

Ronny Richter; Jörg Frauendiener

2010-04-01T23:59:59.000Z

333

Empirical evaluation of conservative and optimistic discrete event execution on cloud and VM platforms  

Science Conference Proceedings (OSTI)

Virtual machine (VM) technologies, especially those offered via Cloud platforms, present new dimensions with respect to performance and cost in executing parallel discrete event simulation (PDES) applications. Due to the introduction of overall cost ... Keywords: cloud computing, conservative simulation, optimistic simulation, parallel discrete event simulation, performance study, virtual machine

Srikanth B. Yoginath, Kalyan S. Perumalla

2013-05-01T23:59:59.000Z

334

On fluidization of discrete event models: observation and control of continuous Petri nets  

Science Conference Proceedings (OSTI)

As a preliminary overview, this work provides first a broad tutorial on the fluidization of discrete event dynamic models, an efficient technique for dealing with the classical state explosion problem. Even if named as continuous or fluid, the ... Keywords: Discrete event systems, Fluidization, Petri nets, Piecewise affine systems, System theory, Untimed and timed models

Manuel Silva; Jorge Júlvez; Cristian Mahulea; C. Renato Vázquez

2011-12-01T23:59:59.000Z

335

Well Posedness of the Initial Value Problem for Vertically Discretized Hydrostatic Equations  

Science Conference Proceedings (OSTI)

Vertically discretized linearized hydrostatic equations in hybrid coordinates are considered. The matrix of vertical structure, which depends on vertical discretization and determines the classification of the obtained system of time-dependent partial ... Keywords: initial value problems, numerical weather prediction, oscillatory matrices, well posedness

Andrei Bourchtein; Vladimir Kadychnikov

2003-01-01T23:59:59.000Z

336

A Sparse Grid SpaceTime Discretization Scheme for Parabolic Problems  

E-Print Network (OSTI)

A Sparse Grid Space­Time Discretization Scheme for Parabolic Problems Michael Griebel, Daniel Oeltz Abstract In this paper we consider the discretization in space and time of parabolic di#erential equations. This holds in many applications due to the smoothing properties of the propagator of the parabolic PDE (heat

Bartels, Soeren

337

Matching pursuit by undecimated discrete wavelet transform for non-stationary time series of arbitrary length  

Science Conference Proceedings (OSTI)

We describe how to formulate a matching pursuit algorithm which successively approximates a periodic non-stationary time series with orthogonal projections onto elements of a suitable dictionary. We discuss how to construct such dictionaries derived ... Keywords: Discrete wavelet transform, matching pursuit, undecimated discrete wavelet transform

A. T. Walden; A. Contreras Cristan

1998-08-01T23:59:59.000Z

338

Predictability of event occurrences in partially-observed discrete-event systems  

Science Conference Proceedings (OSTI)

This paper studies the problem of predicting occurrences of a significant event in a partially-observed discrete-event system. The predictability of occurrences of an event in a system is defined in the context of formal languages. The predictability ... Keywords: Diagnosis, Discrete-event systems, Prediction

Sahika Genc; Stéphane Lafortune

2009-02-01T23:59:59.000Z

339

Modeling and simulation of crowd using cellular discrete event systems theory  

Science Conference Proceedings (OSTI)

In this paper, we discuss how Cellular Discrete Event System Specification (Cell-DEVS) theory can be used in modeling and simulation of the crowd. We will show that the efficient cell update mechanism of Cell-DEVS allows for more efficient entity-based ... Keywords: cellular discrete event systems, crowd, pedestrian

Ronnie Farrell, Mohammad Moallemi, Sixuan Wang, Wang Xiang, Gabriel Wainer

2013-05-01T23:59:59.000Z

340

Timed Discrete Event Control of Parallel Production Lines with Continuous Outputs  

Science Conference Proceedings (OSTI)

In this contribution we present an approach to formulate and solve certain scheduling tasks for hybrid systems using timed discrete event control methods. To demonstrate our approach, we consider a cyclically operated plant with parallel reactors using ... Keywords: Discrete event control, Hybrid systems, Multirate timed automata, Parallel production lines, Scheduling, Verification

Stephanie Geist; Dmitry Gromov; Jörg Raisch

2008-06-01T23:59:59.000Z

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


341

An algorithm for discrete booleans with applications to finite element modeling of complex systems  

Science Conference Proceedings (OSTI)

In this paper we describe a robust algorithm for three-dimensional boolean operations between boundary representation objects whose geometry is given by discrete (faceted) data. The algorithm presents a new approach for computing the intersection graph ... Keywords: Boolean, Discrete, Mesh, Remeshing, Sizing sources, Triangulation

B. Kaan Karamete; Saikat Dey; Eric L. Mestreau; Romain Aubry; Felipe A. Bulat-Jara

2013-06-01T23:59:59.000Z

342

A box-type scheme for fractional sub-diffusion equation with Neumann boundary conditions  

Science Conference Proceedings (OSTI)

Combining order reduction approach and L1 discretization, a box-type scheme is presented for solving a class of fractional sub-diffusion equation with Neumann boundary conditions. A new inner product and corresponding norm with a Sobolev embedding inequality ... Keywords: Box-type scheme, Convergence, Energy method, Neumann boundary conditions, Stability, Sub-diffusion equation

Xuan Zhao; Zhi-zhong Sun

2011-07-01T23:59:59.000Z

343

A condition-based maintenance policy and input parameters estimation for deteriorating systems under periodic inspection  

Science Conference Proceedings (OSTI)

This paper combines an optimization model and input parameters estimation from empirical data, in order to propose condition-based maintenance policies. The system deterioration is described by discrete states ordered from the state ''as good as new'' ... Keywords: Condition-based maintenance, Decision-making under uncertainty, Hidden Markov Models, Optimal control, Stochastic-dynamic programming

Maxstaley L. Neves; Leonardo P. Santiago; Carlos A. Maia

2011-10-01T23:59:59.000Z

344

Simulation on Discrete Fracture Network Using Flexible Voronoi Gridding  

E-Print Network (OSTI)

Fractured reservoirs are generally simulated using Warren and Root26 dual-porosity (DP) approach. The main assumption of this approach is that the geometry of fractures are uniformly distributed and interconnected in reservoirs. This may be true for many cases of naturally fractured reservoirs. However, for a large scale and disconnected fractured reservoirs, DP is often not applicable. Due to the latter case, it is necessary to have more sophisticated simulation studies which allow the fracture to be geometry explicitly represented into the static model using Discrete Fracture Network (DFN) approach. Most work on DFN grid model up to recently has been done with Delaunay tessellations. This research proposes an alternative technique to discretize the two-dimensional DFN using Voronoi diagrams, nevertheless applying the same DFN principles outlined in previous work. Through complicated procedures to generate DFN model, grid system based on Voronoi polygons has been developed. The procedure will force Voronoi edges follow the exact geometry of fractures. Furthermore, implementing the Voronoi diagrams allows the use of fewer polygons than the traditional Local Grid Refinement (LGR). And most importantly, due to the nature of the Voronoi polygons or locally orthogonal grids, the transmissibility calculations can be simplified and are more accurate than corner point formulation for non-square grid blocks. Finally, the main and most important goal of this study is to develop a black-oil Control Volume Finite Difference (CVFD) reservoir simulator that allows us to model DFN more realistically. One of the features of the developed simulator is the capability to model individual fractures with non-uniform aperture distribution, such as log-normally distributed apertures as shown using X-Ray CT scanner measurements. Prior to using the DFN simulator to model reservoirs with fractures and their apertures distribution, the simulator was validated against commercial simulators. The simulator provides results in close agreement with those of a reference finite-difference simulator in cases where direct comparisons are possible. Several simulations of synthetic DFN were presented to demonstrate the robustness of the Voronoi diagrams to represent fracture networks and its aperture distributions. In summary, the simulation of the DFN using the proposed approaches is capable to model both fractured and unfractured systems. However, the DFN model with Voronoi grids requires more efforts on building the grid model compared to other methods. Numerically, simulations of fractured systems are very challenging.

Syihab, Zuher

2009-12-01T23:59:59.000Z

345

CDIAC Atmospheric Moisture Data Sets  

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

Atmospheric Moisture Atmospheric Moisture CDIAC Climate Holdings Containing Atmospheric Moisture Data Global Data Sets Data Set Name Investigators Data Type/Format Period of Record Extended Edited Synoptic Cloud Reports from Ships and Land Stations Over the Globe, 1952-2009 (CDIAC NDP-026C) C.J. Hahn, S.G. Warren, and R. Eastman Six-hourly synoptic observations of dew point depression (combined with air temperature) Land 1971-2009; Ocean 1952-2008 Regional Data Sets Data Set Name Investigators Data Type/Format Period of Record Six- and Three-Hourly Meteorological Observations from 223 Former U.S.S.R. Stations (CDIAC NDP-048) V. Razuvaev et al. Surface stations; 6- and 3-hourly observations of relative humidity, vapor pressure, humidity deficit, and dew point temperature Varies by station; through 2000

346

atmospheric pressure | OpenEI  

Open Energy Info (EERE)

pressure pressure Dataset Summary Description (Abstract):Atmospheric Pressure (kPa)NASA Surface meteorology and Solar Energy (SSE) Release 6.0 Data Set (Nov 2007)22-year Monthly & Annual Average (July 1983 - June 2005)Parameter: Atmospheric Pressure (kPa)Internet: http://eosweb.larc.nasa.gov/sse/Note 1: SSE Methodology & Accuracy sections onlineNote 2: Lat/Lon values indicate the lower left corner of a 1x1 degree region. Negative values are south and west; positive values are north and east. Boundaries of the -90/-180 region Source U.S. National Aeronautics and Space Administration (NASA), Surface meteorology and Solar Energy (SSE) Date Released March 31st, 2009 (5 years ago) Date Updated Unknown Keywords atmospheric pressure climate NASA SWERA UNEP Data text/csv icon Download Data (csv, 46 MiB)

347

CDIAC Atmospheric Pressure Data Sets  

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

Atmospheric Pressure Atmospheric Pressure CDIAC Climate Holdings Containing Atmospheric Pressure Data Global Data Sets Data Set Name Investigators Data Type/Format Period of Record Global Historical Climatology Network (GHCN); Vs. 1 (CDIAC NDP-041) R.S. Vose et al. Surface stations; monthly mean sea-level pressure Varies by station; through 1990 Extended Edited Synoptic Cloud Reports from Ships and Land Stations Over the Globe, 1952-2009 (CDIAC NDP-026C) C.J. Hahn, S.G. Warren, and R. Eastman Six-hourly synoptic observations of sea-level pressure Land 1971-2009; Ocean 1952-2008 Global Historical Climatology Network (GHCN); Vs. 2 (Note: the above link takes you to NOAA's National Climatic Data Center website.) R.S. Vose et al. Surface stations; monthly mean sea-level pressure Varies by station; some through most recent month

348

National Atmospheric Release Advisory Center  

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

NARAC TOC NARAC TOC The National Atmospheric Release Advisory Center, NARAC, provides tools and services to the Federal Government, that map the probable spread of hazardous material accidentally or intentionally released into the atmosphere. NARAC provides atmospheric plume predictions in time for an emergency manager to decide if taking protective action is necessary to protect the health and safety of people in affected areas. Located at the Lawrence Livermore National Laboratory, NARAC is a national support and resource center for planning, real-time assessment, emergency response, and detailed studies of incidents involving a wide variety of hazards, including nuclear, radiological, chemical, biological, and natural emissions. In an emergency situation (if lives are at risk), event-specific NARAC

349

Computer controlled air conditioning systems  

SciTech Connect

This patent describes an improvement in a computer controlled air conditioning system providing for circulation of air through an air conditioned house in contact with concrete walls requiring a humidity within a critical range. The improvement consists of: a computer for processing sensed environmental input data including humidity and oxygen to produce output control signals for affecting the humidity of the air in the house; provision for an air flow circulation path through the house in contact with the concrete walls; sensing responsive to the amount of oxygen in the house for providing input signals to the computer; mixing for combining with the air in the house a variable amount of fresh atmospheric air to supply fresh oxygen; and humidity modifying means for modifying the humidity of the air flowing in the flow path responsive to the control signals.

Dumbeck, R.F.

1986-02-04T23:59:59.000Z

350

Metrics for Availability Analysis Using a Discrete Event Simulation Method  

Science Conference Proceedings (OSTI)

The system performance metric 'availability' is a central concept with respect to the concerns of a plant's operators and owners, yet it can be abstract enough to resist explanation at system levels. Hence, there is a need for a system-level metric more closely aligned with a plant's (or, more generally, a system's) raison d'etre. Historically, availability of repairable systems - intrinsic, operational, or otherwise - has been defined as a ratio of times. This paper introduces a new concept of availability, called endogenous availability, defined in terms of a ratio of quantities of product yield. Endogenous availability can be evaluated using a discrete event simulation analysis methodology. A simulation example shows that endogenous availability reduces to conventional availability in a simple series system with different processing rates and without intermediate storage capacity, but diverges from conventional availability when storage capacity is progressively increased. It is shown that conventional availability tends to be conservative when a design includes features, such as in - process storage, that partially decouple the components of a larger system.

Schryver, Jack C [ORNL; Nutaro, James J [ORNL; Haire, Marvin Jonathan [ORNL

2012-01-01T23:59:59.000Z

351

Propagation of B mesons in the atmosphere  

E-Print Network (OSTI)

Collisions of cosmic rays in the atmosphere may produce heavy hadrons of very high energy. The decay length of a $B$ meson of energy above $10^7$ GeV is larger than 1 km, implying that such a particle tends to interact in the air before it decays. We show that the fraction of energy deposited in these interactions is much smaller than in proton and pion collisions. We parameterize their elasticity and determine the average number of interactions and the atmospheric depth at the decay point for different initial energies. We find that the profile of a $3\\times 10^9$ GeV bottom shower may be very different from the profile of a proton shower of the same energy, defining either a very deep maximum, or two maxima, or other features that cannot be parameterized with a single Gaisser-Hillas function. Finally, we discuss under what conditions a bottom hadron inside the parent air shower may provide observable effects.

A. Bueno; A. Gascon; J. I. Illana; M. Masip

2011-09-20T23:59:59.000Z

352

A Fast Line-by-Line Method for Atmospheric Absorption Computations: The Automatized Atmospheric Absorption Atlas  

Science Conference Proceedings (OSTI)

A computationally fast line-by-line method for the determination of atmospheric absorption is described. This method is based on the creation of an Automatized Atmospheric Absorption Atlas (4A) covering all possible plausible atmospheric ...

N. A. Scott; A. Chedin

1981-07-01T23:59:59.000Z

353

Uptake of tritium by plants from atmosphere and soil  

Science Conference Proceedings (OSTI)

Uptake of tritiated water (HTO) by plants was examined under field conditions when tritium was available to leaves from only the atmosphere and when tritium was available from both the soil (root uptake) and the atmosphere. Maple, oak, and elm trees, planted in clean soil, were transported to a tritium-contaminated forest, where the atmospheric tritium concentration was elevated, to examine HTO uptake by tree leaves when the source was only in the atmosphere. The results partially agreed with a diffusion model of tritium uptake by plants. Discrepancies found between predicted and measured leaf HTO/air HTO ratios should be attributed to the existence of some isolated water, which is isolated from the transpiration stream in the leaves, that was not available for rapid turnover. The uptake of tritium by trees, when the source was both in the soil and atmosphere, was also examined using deciduous trees (maple and elm) resident to the tritium-contaminated forest. The results were in agreement with a prediction model.

Amano, H [Japan Atomic Energy Research Institute (JAERI); Garten Jr, Charles T [ORNL

1991-01-01T23:59:59.000Z

354

Biofabrication of discrete spherical gold nanoparticles using the metal-reducing bacterium, Shewanella oneidensis  

Science Conference Proceedings (OSTI)

Nanocrystallites have garnered substantial interest due to their varying applications including catalysis. Consequently important aspects related to control of shape/size and syntheses through economical and non-hazardous means are desirable. Highly efficient bioreduction based natural fabrication approaches that utilize microbes and or -plant extracts are poised to meet these needs. Here we show that the gamma- proteobacterium, Shewanella oneidensis MR-1, can reduce tetrachloro aurate (III) ions, producing discrete extracellular spherical gold nanocrystallites. The particles were homogeneous with multiple size distributions and produced under ambient conditions at high yield, 88% of theoretical maximum. Further characterization revealed that the particles consist of spheres in the size range of 2-50 nm, with an average of 12 5 nm. The nanoparticles were hydrophilic, biocompatible, and resisted aggregation even after several months. The particles are likely capped by a detachable protein/peptide coat. UV-vis and Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray spectra and transmission electron microscopy measurements confirmed the formation as well the crystalline nature of the nanoparticles. The antibacterial activity of these gold nanoparticles was assessed using Gram-negative (E. coli and S. oneidensis) and Gram-positive (B. subtilis) bacteria. Toxicity assessments divulged that the particles were neither toxic nor inhibitory to any of these bacteria.

Suresh, Anil K [ORNL; Pelletier, Dale A [ORNL; Wang, Wei [ORNL; Broich, Michael L [ORNL; Moon, Ji Won [ORNL; Gu, Baohua [ORNL; Allison, David P [ORNL; Joy, David Charles [ORNL; Phelps, Tommy Joe [ORNL; Doktycz, Mitchel John [ORNL

2011-01-01T23:59:59.000Z

355

Precoding by Pairing Subchannels to Increase MIMO Capacity With Discrete Input Alphabets  

E-Print Network (OSTI)

Abstract—We consider Gaussian multiple-input multiple-output (MIMO) channels with discrete input alphabets. We propose a nondiagonal precoder based on the X-Codes in [1] to increase the mutual information. The MIMO channel is transformed into a set of parallel subchannels using singular value decomposition (SVD) and X-Codes are then used to pair the subchannels. X-Codes are fully characterized by the pairings and a 2 2 2 real rotation matrix for each pair (parameterized with a single angle). This precoding structure enables us to express the total mutual information as a sum of the mutual information of all the pairs. The problem of finding the optimal precoder with the above structure, which maximizes the total mutual information, is solved by: i) optimizing the rotation angle and the power allocation within each pair and ii) finding the optimal pairing and power allocation among the pairs. It is shown that the mutual information achieved with the proposed pairing scheme is very close to that achieved with the optimal precoder by Cruz et al., and is significantly better than Mercury/waterfilling strategy by Lozano et al. Our approach greatly simplifies both the precoder optimization and the detection complexity, making it suitable for practical applications. Index Terms—Condition number, multiple-input multiple-output (MIMO), mutual information, orthogonal frequency division multiplexing (OFDM), precoding, singular value decomposition (SVD). I.

Saif Khan Mohammed; Emanuele Viterbo; Yi Hong; Senior Member; Ananthanarayanan Chockalingam; Senior Member

2010-01-01T23:59:59.000Z

356

Quality Assurance in Atmospheric Modeling  

Science Conference Proceedings (OSTI)

This paper summarizes a number of best practices associated with the use of numerical models of the atmosphere and is motivated by the rapid growth in the number of model users, who have a range of scientific and technical preparations. An underlying ...

Thomas T. Warner

2011-12-01T23:59:59.000Z

357

Geomagnetic Effects on Atmospheric Neutrinos  

E-Print Network (OSTI)

Geomagnetic effects distort the zenith angle distribution of sub--GeV and few--GeV atmospheric neutrinos, breaking the up--down symmetry that would be present in the absence of neutrino oscillations and without a geomagnetic field. The geomagnetic effects also produce a characteristic azimuthal dependence of the $\

Paolo Lipari; T. K. Gaisser; Todor Stanev

1998-03-09T23:59:59.000Z

358

High-energy atmospheric neutrinos  

E-Print Network (OSTI)

High-energy neutrinos, arising from decays of mesons that were produced through the cosmic rays collisions with air nuclei, form unavoidable background noise in the astrophysical neutrino detection problem. The atmospheric neutrino flux above 1 PeV should be supposedly dominated by the contribution of charmed particle decays. These (prompt) neutrinos originated from decays of massive and shortlived particles, $D^\\pm$, $D^0$, $\\bar{D}{}^0$, $D_s^\\pm$, $\\Lambda^+_c$, form the most uncertain fraction of the high-energy atmospheric neutrino flux because of poor explored processes of the charm production. Besides, an ambiguity in high-energy behavior of pion and especially kaon production cross sections for nucleon-nucleus collisions may affect essentially the calculated neutrino flux. There is the energy region where above flux uncertainties superimpose. A new calculation presented here reveals sizable differences, up to the factor of 1.8 above 1 TeV, in muon neutrino flux predictions obtained with usage of known hadronic models, SIBYLL 2.1 and QGSJET-II. The atmospheric neutrino flux in the energy range $10-10^7$ GeV was computed within the 1D approach to solve nuclear cascade equations in the atmosphere, which takes into account non-scaling behavior of the inclusive cross-sections for the particle production, the rise of total inelastic hadron-nucleus cross-sections and nonpower-law character of the primary cosmic ray spectrum. This approach was recently tested in the atmospheric muon flux calculations [1]. The results of the neutrino flux calculations are compared with the Frejus, AMANDA-II and IceCube measurement data.

S. I. Sinegovsky; A. A. Kochanov; T. S. Sinegovskaya

2010-10-12T23:59:59.000Z

359

Discrete Ordinate Quadrature Selection for Reactor-based Eigenvalue Problems  

Science Conference Proceedings (OSTI)

In this paper we analyze the effect of various quadrature sets on the eigenvalues of several reactor-based problems, including a two-dimensional (2D) fuel pin, a 2D lattice of fuel pins, and a three-dimensional (3D) reactor core problem. While many quadrature sets have been applied to neutral particle discrete ordinate transport calculations, the Level Symmetric (LS) and the Gauss-Chebyshev product (GC) sets are the most widely used in production-level reactor simulations. Other quadrature sets, such as Quadruple Range (QR) sets, have been shown to be more accurate in shielding applications. In this paper, we compare the LS, GC, QR, and the recently developed linear-discontinuous finite element (LDFE) sets, as well as give a brief overview of other proposed quadrature sets. We show that, for a given number of angles, the QR sets are more accurate than the LS and GC in all types of reactor problems analyzed (2D and 3D). We also show that the LDFE sets are more accurate than the LS and GC sets for these problems. We conclude that, for problems where tens to hundreds of quadrature points (directions) per octant are appropriate, QR sets should regularly be used because they have similar integration properties as the LS and GC sets, have no noticeable impact on the speed of convergence of the solution when compared with other quadrature sets, and yield more accurate results. We note that, for very high-order scattering problems, the QR sets exactly integrate fewer angular flux moments over the unit sphere than the GC sets. The effects of those inexact integrations have yet to be analyzed. We also note that the LDFE sets only exactly integrate the zeroth and first angular flux moments. Pin power comparisons and analyses are not included in this paper and are left for future work.

Jarrell, Joshua J [ORNL; Evans, Thomas M [ORNL; Davidson, Gregory G [ORNL

2013-01-01T23:59:59.000Z

360

A covariant causal set approach to discrete quantum gravity  

E-Print Network (OSTI)

A covariant causal set (c-causet) is a causal set that is invariant under labeling. Such causets are well-behaved and have a rigid geometry that is determined by a sequence of positive integers called the shell sequence. We first consider the microscopic picture. In this picture, the vertices of a c-causet have integer labels that are unique up to a label isomorphism. This labeling enables us to define a natural metric $d(a,b)$ between time-like separated vertices $a$ and $b$. The time metric $d(a,b)$ results in a natural definition of a geodesic from $a$ to $b$. It turns out that there can be $n\\ge 1$ such geodesics. Letting $a$ be the origin (the big bang), we define the curvature $K(b)$ of $b$ to be $n-1$. Assuming that particles tend to move along geodesics, $K(b)$ gives the tendency that vertex $b$ is occupied. In this way, the mass distribution is determined by the geometry of the c-causet. We next consider the macroscopic picture which describes the growth process of c-causets. We propose that this process is governed by a quantum dynamics given by complex amplitudes. At present, these amplitudes are unknown. But if they can be found, they will determine the (approximate) geometry of the c-causet describing our particular universe. As an illustration, we present a simple example of an amplitude process that may have physical relevance. We also give a discrete analogue of Einstein's field equations.

Stan Gudder

2013-11-15T23:59:59.000Z

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


361

Results from a discrete fracture network model of a Hot Dry Rock system  

Science Conference Proceedings (OSTI)

The work described represents a move towards better representations of the natural fracture system. The discrete fracture network model used during the study was the NAPSAC code (Grindrod et al, 1992). The goals of the work were to investigate the application of discrete fracture network models to Hot Dry Rock systems, increase the understanding of the basic thermal extraction process and more specifically the understanding of the Rosemanowes Phase 2B system. The aim in applying the work to the Rosemanowes site was to use the discrete fracture network approach to integrate a diverse set of field measurements into as simple a model as possible.

Lanyon, G.W.; Batchelor, A.S.; Ledingham, P.

1993-01-28T23:59:59.000Z

362

Discrete-time GeoX/G/1 queue with unreliable server and multiple adaptive delayed vacations  

Science Conference Proceedings (OSTI)

In this paper we consider a discrete-time Geo^X/G/1 queue with unreliable server and multiple adaptive delayed vacations policy in which the vacation time, service time, repair time and the delayed time all follow arbitrary discrete distribution. By ... Keywords: Discrete-time queueing model, Multiple adaptive delayed vacation, Stochastic decomposition, Transient and steady-state distributions, Unreliable, primary, secondary

Yinghui Tang; Xi Yun; Shujuan Huang

2008-10-01T23:59:59.000Z

363

Generation of Turbulence by Atmospheric Gravity Waves  

Science Conference Proceedings (OSTI)

The standard current criterion for the generation of turbulence by atmospheric gravity waves and for the associated limitation on wave growth is based upon the standard criterion for static instability of the unperturbed atmosphere, namely, that ...

Colin O. Hines

1988-04-01T23:59:59.000Z

364

Retrieval of atmospheric properties of extrasolar planets  

E-Print Network (OSTI)

We present a new method to retrieve molecular abundances and temperature profiles from exoplanet atmosphere photometry and spectroscopy. Our method allows us to run millions of 1-D atmosphere models in order to cover the ...

Nikku, Madhusudhan, 1980-

2009-01-01T23:59:59.000Z

365

Interannual Variation of Global Atmospheric Angular Momentum  

Science Conference Proceedings (OSTI)

The relative atmospheric angular momentum (RAM) integrated over the globe is an explicit variable representing the state of the atmospheric general circulation. After removing the annual, semiannual, and higher-frequency components, the filtered ...

Tsing-Chang Chen; Joseph J. Tribbia; Ming-Cheng Yen

1996-10-01T23:59:59.000Z

366

Statistics Education in the Atmospheric Sciences  

Science Conference Proceedings (OSTI)

Analyses of atmospheric sciences data and models are heavily dependent upon statistical and probabilistic reasoning. Statistical methods have played an important role in establishing physical relationships of atmosphere-ocean-land interactions ...

Timothy J. Brown; L. Mark Berliner; Daniel S. Wilks; Michael B. Richman; Christopher K. Wilke

1999-10-01T23:59:59.000Z

367

Atmospheric Control on the Thermohaline Circulation  

Science Conference Proceedings (OSTI)

In an attempt to elucidate the role of atmospheric and oceanic processes in setting a vigorous ocean overturning circulation in the North Atlantic but not in the North Pacific, a comparison of the observed atmospheric circulation and net surface ...

Arnaud Czaja

2009-01-01T23:59:59.000Z

368

The Promise of GPS in Atmospheric Monitoring  

Science Conference Proceedings (OSTI)

This paper provides an overview of applications of the Global Positioning System (GPS) for active measurement of the Earth's atmosphere. Microwave radio signals transmitted by GPS satellites are delayed (refracted) by the atmosphere as they ...

Steven Businger; Steven R. Chiswell; Michael Bevis; Jingping Duan; Richard A. Anthes; Christian Rocken; Randolph H. Ware; Michael Exner; T. VanHove; Fredrick S. Solheim

1996-01-01T23:59:59.000Z

369

Testing and Evaluating Atmospheric Climate Models  

Science Conference Proceedings (OSTI)

Model validation is a crucial process that underpins model development and gives confidence to the results from running models. This article discusses a range of techniques for validating atmosphere models given that the atmosphere is chaotic and incompletely ...

Vicky Pope; Terry Davies

2002-09-01T23:59:59.000Z

370

Sulfuryl fluoride in the global atmosphere  

E-Print Network (OSTI)

The first calibrated high-frequency, high-precision, in situ atmospheric and archived air measurements of the fumigant sulfuryl fluoride (SO[subscript 2]F[subscript 2]) have been made as part of the Advanced Global Atmospheric ...

Muhle, J.

371

Dynamical Processes of Equatorial Atmospheric Angular Momentum  

Science Conference Proceedings (OSTI)

The dynamical processes that drive intraseasonal equatorial atmospheric angular momentum (EAAM) fluctuations are examined with the National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) reanalysis data. ...

Steven B. Feldstein

2006-02-01T23:59:59.000Z

372

VALDRIFT—A Valley Atmospheric Dispersion Model  

Science Conference Proceedings (OSTI)

VALDRIFT (valley drift) is a valley atmospheric transport, diffusion, and deposition model. The model is phenomenological—that is, the dominant meteorological processes governing the behavior of the valley atmosphere are formulated explicitly in ...

K. Jerry Allwine; Xindi Bian; C. David Whiteman; Harold W. Thistle

1997-08-01T23:59:59.000Z

373

A Spontaneously Generated Tropical Atmospheric General Circulation  

Science Conference Proceedings (OSTI)

A series of idealized atmospheric general circulation model (AGCM) experiments are presented. These experiments examine whether and how atmospheric deep moist convection, in the absence of meridional gradients in external forcing, interacts with ...

Ben P. Kirtman; Edwin K. Schneider

2000-07-01T23:59:59.000Z

374

Atmospheric Turbidity in the Polar Regions  

Science Conference Proceedings (OSTI)

Analysis is presented of 800 measurements of atmospheric monochromatic aerosol optical depth made poleward of 65° latitude. The atmosphere of the southern polar region appears to be uncontaminated but is charged with a background aerosol having ...

Glenn E. Shaw

1982-08-01T23:59:59.000Z

375

Advanced Atmospheric Modeling for Emergency Response  

Science Conference Proceedings (OSTI)

Atmospheric transport and diffusion models are an important part of emergency response systems for industrial facilities that have the potential to release significant quantities of toxic or radioactive material into the atmosphere. An advanced ...

Jerome D. Fast; B. Lance O'steen; Robert P. Addis

1995-03-01T23:59:59.000Z

376

Quantitative determination of atmospheric hydroperoxyl radical  

SciTech Connect

A method for the quantitative determination of atmospheric hydroperoxyl radical comprising: (a) contacting a liquid phase atmospheric sample with a chemiluminescent compound which luminesces on contact with hydroperoxyl radical; (b) determining luminescence intensity from the liquid phase atmospheric sample; and (c) comparing said luminescence intensity from the liquid phase atmospheric sample to a standard luminescence intensity for hydroperoxyl radical. An apparatus for automating the method is also included.

Springston, Stephen R. (Upton, NY); Lloyd, Judith (Westbury, NY); Zheng, Jun (Stony Brook, NY)

2007-10-23T23:59:59.000Z

377

INHIBITION OF METHANE ATMOSPHERIC FLAMES BY ...  

Science Conference Proceedings (OSTI)

... atmospheric pressure was studied. The burner temperature was maintained at 65 “C by using a thermostat. The volumetric velocity ...

2011-10-20T23:59:59.000Z

378

North Carolina Refinery Operable Atmospheric Crude Oil ...  

U.S. Energy Information Administration (EIA)

North Carolina Refinery Operable Atmospheric Crude Oil Distillation Capacity as of January 1 (Barrels per Calendar Day)

379

Discretization of continuous ECG based risk metrics using asymmetric and warped entropy measures  

E-Print Network (OSTI)

We investigate several entropy based approaches to finding cut points for discretizing continuous ECG-based risk metrics. We describe two existing approaches, Shannon entropy and asymmetric entropy, and one new approach, ...

Singh, Anima

380

Electromagnetic wave scattering by discrete random media with remote sensing applications  

E-Print Network (OSTI)

The scattering of electromagnetic waves in medium with randomly distributed discrete scatterers is studied. Analytical and numerical solutions to several problems with implications for the active and passive remote sensing ...

Ao, Chi On, 1970-

2001-01-01T23:59:59.000Z

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


381

Plenary lecture 7: fuzzy identification problem for the stationary discrete extremal fuzzy dynamic system  

Science Conference Proceedings (OSTI)

This work deals with the problem of the Stationary Discrete Extremal Fuzzy Dynamic System (SDEFDS) identification and briefly discusses the results developed by G. Sirbiladze. The fuzzy process with possibilistic uncertainty, the source of which is expert ...

Gia Sirbiladze

2009-06-01T23:59:59.000Z

382

Analytic Approximation of Discrete Field Samples with Weighted Sums and the Gridless Computation of Field Derivatives  

Science Conference Proceedings (OSTI)

Objective analysis by weighted sums of discrete observations is equivalent to the approximation of the distribution of an observed parameter by a function which is also analytic, provided that the weighting function is both analytic and positive ...

F. Caracena

1987-12-01T23:59:59.000Z

383

Finite volume discretization of equations describing nonlinear diffusion in Li-Ion batteries  

Science Conference Proceedings (OSTI)

Numerical modeling of electrochemical process in Li-Ion battery is an emerging topic of great practical interest. In this work we present a Finite Volume discretization of electrochemical diffusive processes occurring during the operation of Li-Ion batteries. ...

P. Popov; Y. Vutov; S. Margenov; O. Iliev

2010-08-01T23:59:59.000Z

384

Randomness and determinism in the interplay between the continuum and the discrete  

Science Conference Proceedings (OSTI)

This paper provides a conceptual analysis of the role of the mathematical continuum versus the discrete in the understanding of randomness as a notion with a physical meaning or origin. The presentation is ‘informal’ as we will not ...

Francis Bailly; Giuseppe Longo

2007-04-01T23:59:59.000Z

385

The Spectrum of Non-Local Discrete Schroedinger Operators with a delta-Potential  

E-Print Network (OSTI)

The behaviour of the spectral edges (embedded eigenvalues and resonances) is discussed at the two ends of the continuous spectrum of non-local discrete Schr\\"odinger operators with a $\\delta$-potential. These operators arise by replacing the discrete Laplacian by a strictly increasing $C^1$-function of the discrete Laplacian. The dependence of the results on this function and the lattice dimension are explicitly derived. It is found that while in the case of the discrete Schr\\"odinger operator these behaviours are the same no matter which end of the continuous spectrum is considered, an asymmetry occurs for the non-local cases. A classification with respect to the spectral edge behaviour is also offered.

Fumio Hiroshima; József L?rinczi

2013-09-18T23:59:59.000Z

386

Software evaluation and selection: an evaluation and selection methodology for discrete-event simulation software  

Science Conference Proceedings (OSTI)

For large international companies with their own simulation team it is often hard to select new discrete event simulation software. Often, preferences and application areas between countries differ, and simulation software already in use influences the ...

Tamrat W. Tewoldeberhan; Alexander Verbraeck; Edwin Valentin; Gilles Bardonnet

2002-12-01T23:59:59.000Z

387

Evaluating capacity and expansion opportunities at tank farm: a decision support system using discrete event simulation  

Science Conference Proceedings (OSTI)

This paper presents a discrete event simulation based Decision Support System to evaluate tank farm operations. The Decision Support System was developed in order to reduce capital expenditures and assist in decision making for assessing the impact of ...

Bikram Sharda; Adriana Vazquez

2009-12-01T23:59:59.000Z

388

Intrinsic energy localization through discrete gap breathers in one-dimensional diatomic granular crystals  

E-Print Network (OSTI)

We present a systematic study of the existence and stability of discrete breathers that are spatially localized in the bulk of a one-dimensional chain of compressed elastic beads that interact via Hertzian contact. The ...

Theocharis, G.

389

On Time-Invariant Purified-Output-Based Discrete Time Control  

E-Print Network (OSTI)

Oct 14, 2005 ... On Time-Invariant Purified-Output-Based Discrete Time Control. Aharon Ben-Tal (abental ***at*** ie.technion.ac.il) Stephen Boyd (boyd ***at*** ...

390

System implementation issues of dynamic discrete disaster decision simulation system (D4S2): phase I  

Science Conference Proceedings (OSTI)

Simulation has many advantages in modeling complex systems to facilitate decision making. In this research, an integrated computer system will be developed which incorporates an agent-based discrete event simulator, a geographic information system, a ...

Shengnan Wu; Larry J. Shuman; Bopaya Bidanda; Matthew Kelley; Bryan Lawson; Ken Sochats; Carey D. Balaban

2007-12-01T23:59:59.000Z

391

Configurations de lagrangiens, domaines fondamentaux et sous-groupes discrets de PU(2,1).  

E-Print Network (OSTI)

??L'objet de cette thčse est l'étude de sous-groupes discrets de PU(2,1), groupe des isométries holomorphes de l'espace hyperbolique complexe de dimension (complexe) 2. On s'intéresse… (more)

Paupert, Julien

2005-01-01T23:59:59.000Z

392

Computational intelligence methods: joint use in discrete event simulation model of logistics processes  

Science Conference Proceedings (OSTI)

The objective of the paper is to present the concept of using selected computational intelligence methods in conjunction with discrete event simulation (DES) models of chosen logistics processes. A review of the recent literature in the scope of applications ...

Marek Karkula; Lech Bukowski

2012-12-01T23:59:59.000Z

393

Accuracy and Potential Economic Value of Categorical and Probabilistic Forecasts of Discrete Events  

Science Conference Proceedings (OSTI)

The accuracy and the potential economic value of categorical and probabilistic forecasts of discrete events are discussed. Accuracy is assessed applying known measures of forecast accuracy, and the potential economic value is measured by a ...

Roberto Buizza

2001-09-01T23:59:59.000Z

394

Trajectory-Tracking Scheme in Lagrangian Form for Solving Linear Advection Problems: Interface Spatial Discretization  

Science Conference Proceedings (OSTI)

A previous Lagrangian linear advection scheme (trajectory-tracking scheme) is modified to achieve local mass conservation in this paper, which is more favorable to climate modeling. The discretized tracer parcels are volumes with interfaces ...

Li Dong; Bin Wang

2013-01-01T23:59:59.000Z

395

Model-driven design and implementation of discrete event control for a machine tool control system  

E-Print Network (OSTI)

Symposium on Computer-Aided Control System Design. [7] E. M.of machine tool control system Mode Control Supervisor (MCS)of a discrete event control system depends entirely on the

Liu, Y.; Li, W.; Yamazaki, K.; Fujishima, M.

2007-01-01T23:59:59.000Z

396

Algebraic multigrid for stabilized finite element discretizations of the Navier Stokes equation  

E-Print Network (OSTI)

A multilevel method for the solution of systems of equations generated by stabilized Finite Element discretizations of the Euler and Navier Stokes equations on generalized unstructured grids is described. The method is ...

Okusanya, Tolulope Olawale, 1972 -

2002-01-01T23:59:59.000Z

397

Analysis of Discrete Shallow-Water Models on Geodesic Delaunay Grids with C-Type Staggering  

Science Conference Proceedings (OSTI)

The properties of C-grid staggered spatial discretizations of the shallow-water equations on regular Delaunay triangulations on the sphere are analyzed. Mass-conserving schemes that also conserve either energy or potential enstrophy are derived, ...

Luca Bonaventura; Todd Ringler

2005-08-01T23:59:59.000Z

398

Synthesis of quantized feedback control software for discrete time linear hybrid systems  

Science Conference Proceedings (OSTI)

We present an algorithm that given a Discrete Time Linear Hybrid System${\\cal H}$ returns a correct-by-construction software implementation K for a (near time optimal) robust quantized feedback controller for ${\\cal H}$ along with ...

Federico Mari; Igor Melatti; Ivano Salvo; Enrico Tronci

2010-07-01T23:59:59.000Z

399

Phase Space Volume Conservation under Space and Time Discretization Schemes for the Shallow-Water Equations  

Science Conference Proceedings (OSTI)

Applying concepts of analytical mechanics to numerical discretization techniques for geophysical flows has recently been proposed. So far, mostly the role of the conservation laws for energy- and vorticity-based quantities has been discussed, but ...

Matthias Sommer; Sebastian Reich

2010-11-01T23:59:59.000Z

400

Detecting atmospheric rivers in large climate datasets  

Science Conference Proceedings (OSTI)

Extreme precipitation events on the western coast of North America are often traced to an unusual weather phenomenon known as atmospheric rivers. Although these storms may provide a significant fraction of the total water to the highly managed western ... Keywords: atmospheric rivers, automatic detection of atmospheric rivers, connected component labeling, extreme climate events

Surendra Byna; Prabhat; Michael F. Wehner; Kesheng John Wu

2011-11-01T23:59:59.000Z

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


401

Matching method and exact solvability of discrete PT-symmetric square wells  

E-Print Network (OSTI)

Discrete PT-symmetric square wells are studied. Their wave functions are found proportional to classical Tshebyshev polynomials of complex argument. The compact secular equations for energies are derived giving the real spectra in certain intervals of non-Hermiticity strengths Z. It is amusing to notice that although the known square well re-emerges in the usual continuum limit, a twice as rich, upside-down symmetric spectrum is exhibited by all its present discretized predecessors.

Miloslav Znojil

2006-05-24T23:59:59.000Z

402

Discrete Sampling Test Plan for the 200-BP-5 Operable Unit  

SciTech Connect

The Discrete Groundwater Sampling Project is conducted by the Pacific Northwest National Laboratory (PNNL) on behalf of CH2M HILL Plateau Remediation Company. The project is focused on delivering groundwater samples from proscribed horizons within select groundwater wells residing in the 200-BP-5 Operable Unit (200-BP-5 OU) on the Hanford Site. This document provides the scope, schedule, methodology, and other details of the PNNL discrete sampling effort.

Sweeney, Mark D.

2010-02-04T23:59:59.000Z

403

Exponential stability preservation in discrete-time analogues of artificial neural networks with distributed delays  

Science Conference Proceedings (OSTI)

This paper demonstrates that there is a discrete-time analogue which does not require any restriction on the size of the time-step in order to preserve the exponential stability of an artificial neural network with distributed delays. The analysis exploits ... Keywords: 34K28, 39A11, 39A12, 92B20, Discrete-time analogues, Distributed delays, Exponential stability, Halanay inequalities, Lyapunov sequences

Sannay Mohamad

2008-05-01T23:59:59.000Z

404

Grid-based methods for diatomic quantum scattering problems: a finite-element, discrete variable representation in prolate spheroidal coordinates  

SciTech Connect

We show how to combine finite elements and the discrete variable representation in prolate spheroidal coordinates to develop a grid-based approach for quantum mechanical studies involving diatomic molecular targets. Prolate spheroidal coordinates are a natural choice for diatomic systems and have been used previously in a variety of bound-state applications. The use of exterior complex scaling in the present implementation allows for a transparently simple way of enforcing Coulomb boundary conditions and therefore straightforward application to electronic continuum problems. Illustrative examples involving the bound and continuum states of H2+, as well as the calculation of photoionization cross sections, show that the speed and accuracy of the present approach offer distinct advantages over methods based on single-center expansions.

Tao, Liang; McCurdy, C.W.; Rescigno, T.N.

2008-11-25T23:59:59.000Z

405

Discrete sliding-mode control of a PWM inverter for sinusoidal output waveform synthesis with optimal sliding curve  

SciTech Connect

This paper presents a discrete sliding-mode control scheme with feedforward compensation for the closed-loop regulation of the pulse-width modulated (PWM) inverter used in an uninterruptible power supply (UPS). The proposed feedforward controller can effectively improve the tracking performance of the PWM inverter. In designing the sliding-mode controller, the authors have taken load disturbance into consideration to enhance the robustness of the PWM inverter. Moreover, the upper bound of the load disturbance under which the sliding condition can be maintained has also been derived. The sliding curve of the sliding-mode controller is designed such that the behavior of the controlled PWM inverter is optimal subject to the selected cost function. Due to the coordinate transformation proposed in this paper, only the output voltage needs to be measured as feedback for the purpose of closed-loop regulation. Simulation and experimental results are given to show the effectiveness of the proposed control scheme.

Jung, S.L.; Tzou, Y.Y. [National Chiao Tung Univ., Hsinchu (Taiwan, Province of China). Dept. of Control Engineering

1996-07-01T23:59:59.000Z

406

Stability and phase evolution of mullite in reducing atmosphere  

Science Conference Proceedings (OSTI)

The aim of this study is to investigate the stability of mullite and its phase evolution when heated at 1600-1650 deg. C in reducing atmosphere created by a carbon bed. The stoichiometric mullite (3Al{sub 2}O{sub 3}.2SiO{sub 2}) was synthesized by reacting the proper precursors at 1400 deg. C in air atmosphere. Samples containing the primary mullite and graphite or carbon were prepared by pressing the mix and heated at 1600-1650 deg. C. Products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the stoichiometric mullite could decompose to corundum and alumina-rich mullite. During firing under reducing atmosphere, the stoichiometric mullite became richer in Al{sup 3+} cations. The gaseous SiO compound was found to be released from the sample and reacting with C to form SiC phase. Comparison of general mullite solid solution (Al{sub 4+2x}Si{sub 2-2x}O{sub 10-x}) with alumina-rich mullite obtained from decomposition revealed that x would take different values depending on temperature and atmosphere. The ultimate decomposition product was found to be corundum. - Research Highlights: {yields} This method is a new route for investigation of thermochemical stability of stoichimetric mullite under reducing condition which have done by the authors. {yields} This research has got very good results for stability of mullite at different conditions. {yields} This work has also studied the mechanism of stability of mullite under reducing atmosphere.

Naghizadeh, R., E-mail: rnaghizadeh@iust.ac.ir; Golestani-fard, F.; Rezaie, H.R.

2011-05-15T23:59:59.000Z

407

About ÂŤEffectiveÂŽ Height of the Aerosol Atmosphere in Visible and IR Wavelength Range  

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

"Effective" Height of the Aerosol Atmosphere in "Effective" Height of the Aerosol Atmosphere in Visible and IR Wavelength Range V. N. Uzhegov, D. M. Kabanov, M. V. Panchenko, Yu. A. Pkhalagov, and S. M. Sakerin Institute of Atmospheric Optics Tomsk, Russia Introduction Aerosol component of the atmosphere is one of the important factors affecting the radiation budget of the space - atmosphere - underlying surface system in visible and infrared (IR) wavelength ranges. It is extremely important to take into account the contribution of this component into the extinction of solar radiation under cloudless sky conditions. Sometimes it is important to know not only the total value of the aerosol component of extinction, but also to have the possibility to estimate the "effective" height of

408

Atmospheric Profiles at the Southern Pierre Auger Observatory and their Relevance to Air Shower Measurement  

E-Print Network (OSTI)

The dependence of atmospheric conditions on altitude and time have to be known at the site of an air shower experiment for accurate reconstruction of extensive air showers and their simulations. The height-profile of atmospheric depth is of particular interest as it enters directly into the reconstruction of longitudinal shower development and of the primary energy and mass of cosmic rays. For the southern part of the Auger Observatory, the atmosphere has been investigated in a number of campaigns with meteorological radio soundings and with continuous measurements of ground-based weather stations. Focussing on atmospheric depth and temperature profiles, temporal variations are described and monthly profiles are developed. Uncertainties of the monthly atmospheres that are currently applied in the Auger reconstruction are discussed.

B. Keilhauer; J. Bluemer; R. Engel; D. Gora; P. Homola; H. Klages; J. Pekala; M. Risse; M. Unger; B. Wilczynska; H. Wilczynski; for the Pierre Auger Collaboration

2005-07-12T23:59:59.000Z

409

Application of the adjoint method in atmospheric radiative transfer calculations  

DOE Green Energy (OSTI)

The transfer of solar radiation through a standard mid-latitude summer atmosphere including different amounts of aerosols (from clear to hazy) has been computed. The discrete-ordinates (S/sub N/) method, which has been developed to a high degree of computational efficiency and accuracy primarily for nuclear radiation shielding applications, is employed in a forward as well as adjoint mode. In the adjoint mode the result of a transfer calculation is an importance function (adjoint intensity) which allows the calculation of transmitted fluxes, or other radiative responses, for any arbitrary source distribution. The theory of the adjoint method is outlined in detail and physical interpretations are developed for the adjoint intensity. If, for example, the downward directed solar flux at ground level, F/sub lambda/ (z = 0), is desired for N different solar zenith angles, a regular (forward) radiative transfer calculation must be repeated for each solar zenith angle. In contrast, only 1 adjoint transfer calculation gives F/sub lambda/ (z = 0) for all solar zenith angles in a hazy aerosol atmosphere, for 1 wavelength interval, in 2.3 seconds on a CDC-7600 computer. A total of 155 altitude zones were employed between 0 and 70 km, and the convergence criterion for the ratio of fluxes from successive iterations was set at 2 x 10/sup -3/. Our results demonstrate not only the applicability of the highly efficient modern S/sub N/ codes, but indicate also conceptual and computational advantages when the adjoint formulation of the radiative transfer equation is used.

Gerstl, S.A.W.

1979-01-01T23:59:59.000Z

410

Composition and Reactions of Atmospheric Aerosol Particles  

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

Composition and Reactions of Atmospheric Aerosol Particles Print Composition and Reactions of Atmospheric Aerosol Particles Print Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

411

Composition and Reactions of Atmospheric Aerosol Particles  

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

Composition and Reactions of Composition and Reactions of Atmospheric Aerosol Particles Composition and Reactions of Atmospheric Aerosol Particles Print Wednesday, 29 June 2005 00:00 Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

412

Composition and Reactions of Atmospheric Aerosol Particles  

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

Composition and Reactions of Atmospheric Aerosol Particles Print Composition and Reactions of Atmospheric Aerosol Particles Print Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

413

Acoustic Waves in the Turbulent Atmosphere: A Review  

Science Conference Proceedings (OSTI)

The subject of atmospheric acoustics and its role in atmospheric research and in development of modern methods of ground-based remote sensing of the atmosphere are outlined. A historical overview of investigations of the effect of atmospheric ...

M. A. Kallistratova

2002-08-01T23:59:59.000Z

414

Northern Hemispheric Trends of Pressure Indices and Atmospheric Circulation Patterns in Observations, Reconstructions, and Coupled GCM Simulations  

Science Conference Proceedings (OSTI)

The decadal trend behavior of the Northern Hemisphere atmospheric circulation is investigated utilizing long-term simulations with different state-of-the-art coupled general circulation models (GCMs) for present-day climate conditions (1990), ...

C. C. Raible; T. F. Stocker; M. Yoshimori; M. Renold; U. Beyerle; C. Casty; J. Luterbacher

2005-10-01T23:59:59.000Z

415

Cloud Diabatic Forcing of the Atmosphere, Estimated from Simultaneous ECMWF Diabatic Heating and ISCCP Cloud Amount Observations  

Science Conference Proceedings (OSTI)

The cloud diabatic forcing (CDF) of the atmosphere, defined as the difference between the diabatic heating in average and in clear-sky conditions is estimated from time series of simultaneous observations of diabatic heating and cloud amount. The ...

Peter Siegmund

1993-12-01T23:59:59.000Z

416

The Atmospheric Bridge: The Influence of ENSO Teleconnections on Air–Sea Interaction over the Global Oceans  

Science Conference Proceedings (OSTI)

During El Nińo–Southern Oscillation (ENSO) events, the atmospheric response to sea surface temperature (SST) anomalies in the equatorial Pacific influences ocean conditions over the remainder of the globe. This connection between ocean basins via ...

Michael A. Alexander; Ileana Bladé; Matthew Newman; John R. Lanzante; Ngar-Cheung Lau; James D. Scott

2002-08-01T23:59:59.000Z

417

Impact of Surface Flux Formulations and Geostrophic Forcing on Large-Eddy Simulations of Diurnal Atmospheric Boundary Layer Flow  

Science Conference Proceedings (OSTI)

The impact of surface flux boundary conditions and geostrophic forcing on multiday evolution of flow in the atmospheric boundary layer (ABL) was assessed using large-eddy simulations (LES). The LES investigations included several combinations of ...

Vijayant Kumar; Gunilla Svensson; A. A. M. Holtslag; Charles Meneveau; Marc B. Parlange

2010-07-01T23:59:59.000Z

418

Diagnosing the strength of land-atmosphere coupling at sub-seasonal to seasonal time scales in Asia  

Science Conference Proceedings (OSTI)

This paper focuses on diagnosing the strength of soil moisture-atmosphere coupling at sub-seasonal to seasonal time scales over Asia using two different approaches, the conditional correlation approach (applied to the GLDAS data, the CFSR ...

Di Liu; Guiling Wang; Rui Mei; Zhongbo Yu; Huanghe Gu

419

Flow Boundaries in Random-Flight Dispersion Models: Enforcing the Well-Mixed Condition  

Science Conference Proceedings (OSTI)

Lagrangian stochastic (LS) dispersion models often use trajectory reflection to limit the domain accessible to a particle. It is shown how the well-mixed condition (Thomson) can he expressed in the Chapman-Kolmogorov equation for a discrete-time ...

John D. Wilson; Thomas K. Flesch

1993-11-01T23:59:59.000Z

420

CFL Conditions for Runge-Kutta discontinuous Galerkin methods on triangular grids  

Science Conference Proceedings (OSTI)

We study time step restrictions due to linear stability constraints of Runge-Kutta Discontinuous Galerkin methods on triangular grids. The scalar advection equation is discretized in space by the Discontinuous Galerkin method with either the Lax-Friedrichs ... Keywords: CFL condition, Discontinuous Galerkin, Linear stability, Runge-Kutta

T. Toulorge; W. Desmet

2011-06-01T23:59:59.000Z

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


421

Fault conditions classification of automotive generator using an adaptive neuro-fuzzy inference system  

Science Conference Proceedings (OSTI)

In this paper, an adaptive neuro-fuzzy inference system (ANFIS) was proposed for condition monitoring and fault diagnosis of an automotive generator. Conventional fault indication of an automotive generator generally uses an indicator to inform the driver ... Keywords: Adaptive neuro-fuzzy inference system, Automotive generator, Discrete wavelet transform, Fault diagnosis system

Jian-Da Wu; Jun-Ming Kuo

2010-12-01T23:59:59.000Z

422

Regional Ecosystem-Atmosphere CO2 Exchange Via Atmospheric Budgets  

Science Conference Proceedings (OSTI)

Inversions of atmospheric CO2 mixing ratio measurements to determine CO2 sources and sinks are typically limited to coarse spatial and temporal resolution. This limits our ability to evaluate efforts to upscale chamber- and stand-level CO2 flux measurements to regional scales, where coherent climate and ecosystem mechanisms govern the carbon cycle. As a step towards the goal of implementing atmospheric budget or inversion methodology on a regional scale, a network of five relatively inexpensive CO2 mixing ratio measurement systems was deployed on towers in northern Wisconsin. Four systems were distributed on a circle of roughly 150-km radius, surrounding one centrally located system at the WLEF tower near Park Falls, WI. All measurements were taken at a height of 76 m AGL. The systems used single-cell infrared CO2 analyzers (Licor, model LI-820) rather than the siginificantly more costly two-cell models, and were calibrated every two hours using four samples known to within ± 0.2 ppm CO2. Tests prior to deployment in which the systems sampled the same air indicate the precision of the systems to be better than ± 0.3 ppm and the accuracy, based on the difference between the daily mean of one system and a co-located NOAA-ESRL system, is consistently better than ± 0.3 ppm. We demonstrate the utility of the network in two ways. We interpret regional CO2 differences using a Lagrangian parcel approach. The difference in the CO2 mixing ratios across the network is at least 2?3 ppm, which is large compared to the accuracy and precision of the systems. Fluxes estimated assuming Lagrangian parcel transport are of the same sign and magnitude as eddy-covariance flux measurements at the centrally-located WLEF tower. These results indicate that the network will be useful in a full inversion model. Second, we present a case study involving a frontal passage through the region. The progression of a front across the network is evident; changes as large as four ppm in one minute are captured. Influence functions, derived using a Lagrangian Particle Dispersion model driven by the CSU Regional Atmospheric Modeling System and nudged to NCEP reanalysis meteorological fields, are used to determine source regions for the towers. The influence functions are combined with satellite vegetation observations to interpret the observed trends in CO2 concentration. Full inversions will combine these elements in a more formal analytic framework.

Davis, K.J.; Richardson, S.J.; Miles, N.L.

2007-03-07T23:59:59.000Z

423

Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres  

SciTech Connect

This report covers the second year of the 28 month grant current grant to Clarkson University to study the chemical and physical behavior of the polonium 218 atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and it dose to the cells in the respiratory tract are to be fully assessed. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical process that affect the progeny's atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. This report describes the progress toward achieving these objectives.

Hopke, P.K.

1992-07-01T23:59:59.000Z

424

High-energy atmospheric neutrinos  

E-Print Network (OSTI)

High-energy neutrinos, arising from decays of mesons that were produced through the cosmic rays collisions with air nuclei, form unavoidable background noise in the astrophysical neutrino detection problem. The atmospheric neutrino flux above 1 PeV should be supposedly dominated by the contribution of charmed particle decays. These (prompt) neutrinos originated from decays of massive and shortlived particles, $D^\\pm$, $D^0$, $\\bar{D}{}^0$, $D_s^\\pm$, $\\Lambda^+_c$, form the most uncertain fraction of the high-energy atmospheric neutrino flux because of poor explored processes of the charm production. Besides, an ambiguity in high-energy behavior of pion and especially kaon production cross sections for nucleon-nucleus collisions may affect essentially the calculated neutrino flux. There is the energy region where above flux uncertainties superimpose. A new calculation presented here reveals sizable differences, up to the factor of 1.8 above 1 TeV, in muon neutrino flux predictions obtained with usage of known...

Sinegovsky, S I; Sinegovskaya, T S

2010-01-01T23:59:59.000Z

425

A fast iterative model for discrete velocity calculations on triangular grids  

SciTech Connect

A fast synthetic type iterative model is proposed to speed up the slow convergence of discrete velocity algorithms for solving linear kinetic equations on triangular lattices. The efficiency of the scheme is verified both theoretically by a discrete Fourier stability analysis and computationally by solving a rarefied gas flow problem. The stability analysis of the discrete kinetic equations yields the spectral radius of the typical and the proposed iterative algorithms and reveal the drastically improved performance of the latter one for any grid resolution. This is the first time that stability analysis of the full discrete kinetic equations related to rarefied gas theory is formulated, providing the detailed dependency of the iteration scheme on the discretization parameters in the phase space. The corresponding characteristics of the model deduced by solving numerically the rarefied gas flow through a duct with triangular cross section are in complete agreement with the theoretical findings. The proposed approach may open a way for fast computation of rarefied gas flows on complex geometries in the whole range of gas rarefaction including the hydrodynamic regime.

Szalmas, Lajos [Department of Mechanical Engineering, University of Thessaly, Pedion Areos, Volos 38334 (Greece); Valougeorgis, Dimitris [Department of Mechanical Engineering, University of Thessaly, Pedion Areos, Volos 38334 (Greece)], E-mail: diva@mie.uth.gr

2010-06-01T23:59:59.000Z

426

Atmospheric neutrino flux at INO site  

Science Conference Proceedings (OSTI)

To illustrate the calculation of the atmospheric neutrino flux, we briefly explain our calculation scheme and important components, such as primary cosmic ray spectra, interaction model, and geomagnetic model. Then, we calculate the atmospheric neutrino flux at INO site in our calculation scheme. We compare the calculated atmospheric neutrino fluxes predicted at INO with those at other major neutrino detector sites, especially that at SK site.

Honda, Morihiro [Institute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8582 (Japan)

2011-11-23T23:59:59.000Z

427

Suppression of dynamics in coupled discrete systems in interaction with an extended environment  

E-Print Network (OSTI)

We report the suppression of dynamics and occurrence of quiescent states in an extended system of coupled discrete dynamical systems. This phenomenon is induced by interaction with another similar system with a different and damped dynamics which we call an extended environment. Both the system and the environment are in a feedback loop and their mutual influence leads to suppression of dynamic activity. We illustrate this in the specific case of a system of coupled neurons modelled by a 2-dimensional discrete system called Rulkov maps. A detailed analysis is carried out by considering single units of discrete systems where control to steady states is induced by an external damped system. This is then extended to rings and lattices. As an important application, we also present how the excitation waves produced due to defect neurons can be suppressed by interaction with a system of passive cells.

Snehal M. Shekatkar; G. Ambika

2013-06-10T23:59:59.000Z

428

Analytical transformed harmonic oscillator basis for continuum discretized coupled channels calculations  

Science Conference Proceedings (OSTI)

A new method for continuum discretization in continuum-discretized coupled-channels calculations is proposed. The method is based on an analytic local-scale transformation of the harmonic-oscillator wave functions proposed for other purposes in a recent work [Karatagladis et al., Phys. Rev. C 71, 064601 (2005)]. The new approach is compared with the standard method of continuum discretization in terms of energy bins for the reactions d+{sup 58}Ni at 80 MeV, {sup 6}Li+{sup 40}Ca at 156 MeV, and {sup 6}He+{sup 208}Pb at 22 MeV and 240 MeV/nucleon. In all cases very good agreement between both approaches is found.

Moro, A. M.; Arias, J. M. [Departamento de Fisica Atomica, Molecular y Nuclear, Facultad de Fisica, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla (Spain); Gomez-Camacho, J. [Departamento de Fisica Atomica, Molecular y Nuclear, Facultad de Fisica, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla (Spain); Centro Nacional de Aceleradores, Avda Thomas A. Edison, E-41092 Sevilla (Spain); Perez-Bernal, F. [Departamento de Fisica Aplicada, Universidad de Huelva, E-21071 Huelva (Spain)

2009-11-15T23:59:59.000Z

429

Parallel Jacobian-free Newton Krylov solution of the discrete ordinates method with flux limiters for 3D radiative transfer  

Science Conference Proceedings (OSTI)

The present study introduces a parallel Jacobian-free Newton Krylov (JFNK) general minimal residual (GMRES) solution for the discretized radiative transfer equation (RTE) in 3D, absorbing, emitting and scattering media. For the angular and spatial discretization ... Keywords: Collimated radiation, Discrete ordinates method (DOM) SN, Electromagnetic radiation, Flux limiters, General Minimal Residual (GMRES), Gram-Schmidt, Householder, Jacobian free Newton-Krylov (JFNK), Parallel MPI, Radiative transfer equation (RTE), TVD, Threads

William F. Godoy; Xu Liu

2012-06-01T23:59:59.000Z

430

Earth and Atmospheric Sciences | More Science | ORNL  

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

Nuclear Forensics Climate & Environment Sensors and Measurements Chemical & Engineering Materials Computational Earth Science Systems Modeling Geographic Information Science and Technology Materials Science and Engineering Mathematics Physics More Science Home | Science & Discovery | More Science | Earth and Atmospheric Sciences SHARE Earth and Atmospheric Sciences At ORNL, we combine our capabilities in atmospheric science, computational science, and biological and environmental systems science to focus in the cross-disciplinary field of climate change science. We use computer models to improve climate change predications and to measure the impact of global warming on the cycling of chemicals in earth systems. Our Climate Change Science Institute uses models to explore connections among atmosphere,

431

Atmospheric carbon dioxide and the greenhouse effect  

SciTech Connect

This document contains a non-technical review of the problems associated with atmospheric carbon dioxide and the resulting greenhouse effect. (TEM)

Firestine, M.W. (ed.)

1989-05-01T23:59:59.000Z

432

NREL: Process Development and Integration Laboratory - Atmospheric  

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

Atmospheric Processing Platform Capabilities Atmospheric Processing Platform Capabilities The Atmospheric Processing platform in the Process Development and Integration Laboratory offers powerful capabilities with integrated tools for depositing, processing, and characterizing photovoltaic materials and devices. In particular, this platform focuses on different methods to deposit ("write") materials onto a variety of substrates and then further process into optoelectronic materials using rapid thermal processing. You can read more on the rationale for developing this platform and its capabilities. Contact Maikel van Hest for more details on these capabilities. The Atmospheric Processing platform will allow deposition in any sequence and is applicable to activities in all Technology Roadmaps, which include

433

Mesoscale Coupled Ocean-Atmosphere Interaction  

E-Print Network (OSTI)

small-scale features in ocean winds. Science, 303, Chelton,of the regional coupled ocean-atmosphere model RCAO. Borealstress dependence on ocean surface velocity: implications

Seo, Hyodae

2007-01-01T23:59:59.000Z

434

Mesoscale coupled ocean-atmosphere interaction  

E-Print Network (OSTI)

small-scale features in ocean winds. Science, 303, Chelton,of the regional coupled ocean-atmosphere model RCAO. Borealstress dependence on ocean surface velocity: implications

Seo, Hyodae

2007-01-01T23:59:59.000Z

435

FOAM:The Fast Ocean Atmosphere Model  

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

Models Performance User Resources Publications History Developer's Page FOAM The Fast Ocean Atmosphere Model cup2.jpeg (48474 bytes) Image made by Johan Kellum with Vis5D...

436

12.815 Atmospheric Radiation, Fall 2005  

E-Print Network (OSTI)

Introduction to the physics of atmospheric radiation and remote sensing including use of computer codes. Radiative transfer equation including emission and scattering, spectroscopy, Mie theory, and numerical solutions. ...

Prinn, Ronald G.

437

Atmospheric Radiation Measurement Convective and Orographically...  

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

Induced Precipitation Study The U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility is providing the ARM Mobile Facility...

438

Atmospheric Radiation Measurement Program Climate Research Facility...  

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

2 Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report October 1-December 31, 2010 DISCLAIMER This report was prepared as an account of...

439

Atmospheric Radiation Measurement Program Climate Research Facility...  

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

9 Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report April 1-June 30, 2011 DISCLAIMER This report was prepared as an account of work...

440

Jefferson Lab Science Series - Investigating Earth's Atmosphere  

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

Byron Meadows - NASALangley Research Center May 14, 1991 Demonstrations of weather forecasting tools and techniques for experiments in the atmosphere and of lasers used to...

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


441

Total Atmospheric Crude Oil Distillation Capacity Former ...  

U.S. Energy Information Administration (EIA)

Former Corporation/Refiner Total Atmospheric Crude Oil Distillation Capacity (bbl/cd)a New Corporation/Refiner Date of Sale Table 14. Refinery Sales During 2005

442

Two-phase flow modeling with discrete particles  

SciTech Connect

The design of efficient heat exchangers in which the working fluid changes phase requires accurate modeling of two-phase fluid flow. The local Navier-Stokes equations form the basic continuum equations for this flow situation. However, the local instantaneous model using these equations is intractable for afl but the simplest problems. AH the practical models for two-phase flow analysis are based on equations that have been averaged over control volumes. These models average out the detailed description within the control volumes and rely on flow regime maps to determine the distribution of the two phases within a control volume. Flow regime maps depend on steady state models and probably are not correct for dynamic models. Numerical simulations of the averaged two-phase flow models are usually performed using a two-fluid Eulerian description for the two phases. Eulerian descriptions have the advantage of having simple boundary conditions, but the disadvantage of introducing numerical diffusion, i.e., sharp interfaces are not maintained as the flow develops, but are diffused. Lagrangian descriptions have the advantage of being able to track sharp interfaces without diffusion, but they have the disadvantage of requiring more complicated boundary conditions. This paper describes a numerical scheme and attendant computer program, DISCON2, for the calculation of two-phase flows that does not require the use of flow regime maps. This model is intermediate between the intractable local instantaneous and the averaged two-fluid model. This new model uses a combination of an Eulerian and a Lagrangian representation of the two phases. The dispersed particles (bubbles or drops) are modeled individually using a large representative number of particles, each with their own Lagrangian description. The continuous phases (liquid or gas) use an Eulerian description.

Mortensen, G.A. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Trapp, J.A. (Colorado Univ., Denver, CO (United States) EG and G Idaho, Inc., Idaho Falls, ID (United States))

1992-03-23T23:59:59.000Z

443

Semiclassical energy conditions  

E-Print Network (OSTI)

We present and develop several nonlinear energy conditions suitable for use in the semiclassical regime. In particular, we consider the recently formulated "flux energy condition" (FEC), and the novel "trace-of-square" (TOSEC) and "determinant" (DETEC) energy conditions. As we shall show, these nonlinear energy conditions behave much better than the classical linear energy conditions in the presence of semiclassical quantum effects. Moreover, whereas the quantum extensions of these nonlinear energy conditions seem to be quite widely satisfied as one enters the quantum realm, analogous quantum extensions are generally not useful for the linear classical energy conditions.

Martin-Moruno, Prado

2013-01-01T23:59:59.000Z

444

COHOMOLOGIE GALOISIENNE DES CORPS VALU'ES DISCRETS HENSELIENS, d'apr`es K. Kato et S. Bloch  

E-Print Network (OSTI)

* *orps valu'e discret hens'elien E de caract'eristique nulle et de caract'eristique r'esi* *duelle p

Colliot-Thelene, Jean-Louis

445

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

Science Conference Proceedings (OSTI)

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

Ali Harzallah; Robert Sadourny

1995-03-01T23:59:59.000Z

446

Transient Response of a Global Ocean-Atmosphere Model to a Doubling of Atmospheric Carbon Dioxide  

Science Conference Proceedings (OSTI)

The transient response of climate to an instantaneous increase in the atmospheric concentration of carbon dioxide has been investigated by a general circulation model of the coupled ocean-atmosphere-land system with global geography and annual ...

Syukuro Manabe; Kirk Bryan; Michael J. Spelman

1990-05-01T23:59:59.000Z

447

Measurements of Atmospheric Methane and 13C/12C of Atmospheric...  

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

Methane and 13C12C, Flask Air Samples Measurements of Atmospheric Methane and 13C12C of Atmospheric Methane from Flask Air Samples (1999) data Data Investigators Paul Quay and...

448

Response of the Middle Atmosphere to CO2 Doubling: Results from the Canadian Middle Atmosphere Model  

Science Conference Proceedings (OSTI)

The Canadian Middle Atmosphere Model (CMAM) has been used to examine the middle atmosphere response to CO2 doubling. The radiative-photochemical response induced by doubling CO2 alone and the response produced by changes in prescribed SSTs are ...

V. I. Fomichev; A. I. Jonsson; J. de Grandpré; S. R. Beagley; C. McLandress; K. Semeniuk; T. G. Shepherd

2007-04-01T23:59:59.000Z

449

Coincidence of the continuous and discrete p-adic wavelet transforms  

E-Print Network (OSTI)

We show that translations and dilations of a p-adic wavelet coincides (up to the multiplication by some root of one) with a vector from the known basis of discrete p-adic wavelets. In this sense the continuous p-adic wavelet transform coincides with the discrete p-adic wavelet transform. The p-adic multiresolution approximation is introduced and relation with the real multiresolution approximation is described. Relation of application of p-adic wavelets to spectral theory of p-adic pseudodifferential operators and the known results about sparsity of matrices of some real integral operators in the bases of multiresolution wavelets is discussed.

S. Albeverio; S. V. Kozyrev

2007-02-02T23:59:59.000Z

450

L'Hospital-type rules for monotonicity and limits: Discrete case  

E-Print Network (OSTI)

Assuming that a "derivative" ratio rho:=f'/g' of the ratio r:=f/g of differentiable functions f and g is monotonic (that is, rho is increasing or decreasing), it was shown in previous papers that then r can switch at most once, from decrease to increase or vice versa. In the present paper, "discrete" versions of such l'Hospital-type rules for monotonicity (as well as "discrete" versions of l'Hospital's rules for limits) are obtained, for functions f and g defined on an interval of integers.

Iosif Pinelis

2006-11-21T23:59:59.000Z

451

Discrete Scale Invariance and Other Cooperative Phenomena in Spatially Extended Systems With Threshold Dynamics  

E-Print Network (OSTI)

Contents 1 Introduction 5 1.1 Imitation and Synchronisation . . . . . . . . . . . . . . . . . . . . 6 1.2 Fractals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.3 Hierarchical systems . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.4 1=f-noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.5 Scale invariance and discrete scale invariance . . . . . . . . . . . . 11 1.6 Exactly solvable models with discrete scale invariance . . . . . . 14 1.6.1 Potts model on a hierarchical lattice . . . . . . . . . . . . 14 1.6.2 Diffusion on a random lattice . . . . . . . . . . . . . . . . 19 1.6.3 An experimental hierarchical model . . . . . . . . . . . . . 21 1.7 Possible log-periodic signatures in cracking 1 . . . . . . . . . . . . 22 2 Hierarchical structures in growth models 27 2.1 Laplacian growth models . . . . . . . . . . . . . . . . . . . . . . . 27 2.1.1 Numerical results . . .

Anders Johansen; Anders Johansen

1997-01-01T23:59:59.000Z

452

Atmospheric Longwave Irradiance Uncertainty: Pyrgeometers Compared to an Absolute Sky-Scanning Radiometer, Atmospheric Emitted Radiance Interferometer, and Radiative Transfer Model Calculations  

SciTech Connect

Because atmospheric longwave radiation is one of the most fundamental elements of an expected climate change, there has been a strong interest in improving measurements and model calculations in recent years. Important questions are how reliable and consistent are atmospheric longwave radiation measurements and calculations and what are the uncertainties? The First International Pyrgeometer and Absolute Sky-scanning Radiometer Comparison, which was held at the Atmospheric Radiation Measurement program's Souther Great Plains site in Oklahoma, answers these questions at least for midlatitude summer conditions and reflects the state of the art for atmospheric longwave radiation measurements and calculations. The 15 participating pyrgeometers were all calibration-traced standard instruments chosen from a broad international community. Two new chopped pyrgeometers also took part in the comparison. And absolute sky-scanning radiometer (ASR), which includes a pyroelectric detector and a reference blackbody source, was used for the first time as a reference standard instrument to field calibrate pyrgeometers during clear-sky nighttime measurements. Owner-provided and uniformly determined blackbody calibration factors were compared. Remarkable improvements and higher pyrgeometer precision were achieved with field calibration factors. Results of nighttime and daytime pyrgeometer precision and absolute uncertainty are presented for eight consecutive days of measurements, during which period downward longwave irradiance varied between 260 and 420 W m-2. Comparisons between pyrgeometers and the absolute ASR, the atmospheric emitted radiance interferometer, and radiative transfer models LBLRTM and MODTRAN show a surprisingly good agreement of <2 W m-2 for nighttime atmospheric longwave irradiance measurements and calculations.

Philipona, J. R.; Dutton, Ellsworth G.; Stoffel, T.; Michalsky, Joseph J.; Reda, I.; Stifter, Armin; Wendling, Peter; Wood, Norm; Clough, Shepard A.; Mlawer, Eli J.; Anderson, Gail; Revercomb, Henry E.; Shippert, Timothy R.

2001-06-04T23:59:59.000Z

453

Regional forecasting with global atmospheric models; Final report  

SciTech Connect

The purpose of the project was to conduct model simulations for past and future climate change with respect to the proposed Yucca Mtn. repository. The authors report on three main topics, one of which is boundary conditions for paleo-hindcast studies. These conditions are necessary for the conduction of three to four model simulations. The boundary conditions have been prepared for future runs. The second topic is (a) comparing the atmospheric general circulation model (GCM) with observations and other GCMs; and (b) development of a better precipitation data base for the Yucca Mtn. region for comparisons with models. These tasks have been completed. The third topic is preliminary assessments of future climate change. Energy balance model (EBM) simulations suggest that the greenhouse effect will likely dominate climate change at Yucca Mtn. for the next 10,000 years. The EBM study should improve rational choice of GCM CO{sub 2} scenarios for future climate change.

Crowley, T.J.; Smith, N.R. [Applied Research Corp., College Station, TX (United States)

1994-05-01T23:59:59.000Z

454

Images reveal that atmospheric particles can undergo liquid-liquid phase separations  

Science Conference Proceedings (OSTI)

A large fraction of submicron atmospheric particles contains both organic material and inorganic salts. As the relative humidity cycles in the atmosphere, these mixed particles can undergo a range of phase transitions, possibly including liquid-liquid phase separation. If liquid-liquid phase separation occurs, the gas-particle partitioning of atmospheric semi-volatile organic compounds, the scattering and absorption of solar radiation, and the uptake of reactive gas species on atmospheric particles will be affected, with important implications for climate predictions. The actual occurrence of these types of phase transitions within individual atmospheric particles has been considered uncertain, in large part because of the absence of observations for real-world samples. Here, using optical and fluorescence microscopy, we observe the coexistence of two non-crystalline phases in particles generated from real-world samples collected on multiple days in Atlanta, Georgia, and in particles generated in the laboratory using atmospheric conditions. These results reveal that atmospheric particles can undergo liquid-liquid phase separations. Using a box model, we show that liquid-liquid phase separation can result in increased concentrations of gas-phase NO3 and N2O5 in the Atlanta region, due to decreased particle uptake of N2O5.

You, Yuan; Renbaum-Wolff, Lindsay; Carreras-Sospedra, Marc; Hanna, Sarah; Hiranuma, Naruki; Kamal, Saeid; Smith, Mackenzie L.; Zhang, Xiaolu; Weber, Rodney; Shilling, John E.; Dabdub, Donald; Martin, Scot T.; Bertram, Allan K.

2012-07-30T23:59:59.000Z

455

Aerosol Radiative Forcing Under Cloudless Conditions.in Winter ZCAREX-2001  

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

Forcing Under Cloudless Conditions Forcing Under Cloudless Conditions in Winter ZCAREX-2001 G. S. Golitsyn, I. A. Gorchakova, and I. I. Mokhov Institute of Atmospheric Physic Moscow, Russia Introduction Aerosol radiative forcing (ARF) is estimated for winter clear-sky conditions from measurements during ZCAREX-2001-Cloud-Aerosol-Radiation Experiment in February-March, 2001 at the Zvenigorod Scientific Station (ZSS) of the A.M. Obukhov Institute of Atmospheric Physics RAS. ARF in the shortwave range is determined by the difference between the net fluxes of the solar radiation, calculated with and without the aerosol component of the atmosphere. The estimates of ARF are made for conditions with high surface albedo. Data Used The following data of atmospheric characteristics observed during winter are used for the

456

Variation of Hydrometeorological Conditions along a Topographic Transect in Northwestern Mexico during the North American Monsoon  

Science Conference Proceedings (OSTI)

Relatively little is currently known about the spatiotemporal variability of land surface conditions during the North American monsoon, in particular for regions of complex topography. As a result, the role played by land–atmosphere interactions ...

Enrique R. Vivoni; Hugo A. Gutiérrez-Jurado; Carlos A. Aragón; Luis A. Méndez-Barroso; Alex J. Rinehart; Robert L. Wyckoff; Julio C. Rodríguez; Christopher J. Watts; John D. Bolten; Venkataraman Lakshmi; Thomas J. Jackson

2007-05-01T23:59:59.000Z

457

Heavy Precipitation Events in New Jersey: Attendant Upper-Air Conditions  

Science Conference Proceedings (OSTI)

The first of an anticipated multipart study of atmospheric conditions occurring before and during heavy precipitation events in New Jersey, representative of the mid-Atlantic region, is presented. Upper-air data parameters were analyzed for 81 ...

Robert P. Harnack; Kirk Apffel; Joseph R. Cermak III

1999-12-01T23:59:59.000Z

458

Numerical Studies of Urban Planetary Boundary-Layer Structure under Realistic Synoptic Conditions  

Science Conference Proceedings (OSTI)

The Pennsylvania State University (PSU)/National Center for Atmospheric Research (NCAR) mesoscale model was modified and used to simulate the evolution of meteorological conditions in the vicinity of St. Louis, Missouri, from near sunrise to noon ...

Nelson L. Seaman; Francis L. Ludwig; Evelyn G. Donall; Thomas T. Warner; Chandrakant M. Bhumralkar

1989-08-01T23:59:59.000Z

459

Response of Thermohaline Circulation to Freshwater Forcing under Present-Day and LGM Conditions  

Science Conference Proceedings (OSTI)

Responses of the thermohaline circulation (THC) to freshwater forcing (hosing) in the subpolar North Atlantic Ocean under present-day and the last glacial maximum (LGM) conditions are investigated using the National Center for Atmospheric ...

Aixue Hu; Bette L. Otto-Bliesner; Gerald A. Meehl; Weiqing Han; Carrie Morrill; Esther C. Brady; Bruce Briegleb

2008-05-01T23:59:59.000Z

460

The Behavior of the Snow White Chilled-Mirror Hygrometer in Extremely Dry Conditions  

Science Conference Proceedings (OSTI)

The Snow White hygrometer, made by Meteolabor AG, Switzerland, is a new chilled-mirror instrument using a thermoelectric Peltier cooler to measure atmospheric water vapor. Its performance under dry conditions is evaluated in simultaneous ...

H. Vömel; M. Fujiwara; M. Shiotani; F. Hasebe; S. J. Oltmans; J. E. Barnes

2003-11-01T23:59:59.000Z

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


461

An Analysis of the Klemp and Durran Radiation Boundary Condition as Applied to Dissipative Internal Waves  

Science Conference Proceedings (OSTI)

Numerical simulations of the oceanic (atmospheric) boundary layer are complicated by the need to specify appropriate “outflow” or “radiation” boundary conditions at the artificial lower (upper) boundary of the computational domain. If the ...

Gregory P. Chini; Sidney Leibovich

2003-11-01T23:59:59.000Z

462

Experimental Study on Wind-Wave Momentum Flux in Strongly Forced Conditions  

Science Conference Proceedings (OSTI)

A quantitative description of wind-wave momentum transfer in high wind conditions is necessary for accurate wave models, storm and hurricane forecasting, and models that require atmosphere–ocean coupling such as circulation and mixed layer models. ...

Ivan B. Savelyev; Brian K. Haus; Mark A. Donelan

2011-07-01T23:59:59.000Z

463

Climatological Conditions of Lake-Effect Precipitation Events Associated with the New York State Finger Lakes  

Science Conference Proceedings (OSTI)

A climatological analysis was conducted of the environmental and atmospheric conditions that occurred during 125 identified lake-effect (LE) precipitation events in the New York State Finger Lakes region for the 11 winters (October–March) from ...

Neil Laird; Ryan Sobash; Natasha Hodas

2010-05-01T23:59:59.000Z

464

Influence of Initial Conditions on Summer Precipitation Simulations over the United States and Mexico  

Science Conference Proceedings (OSTI)

The impact of initial conditions on summer precipitation over North America for July–September was examined by comparing long-term simulations of the Atmospheric Model Intercomparison Project (AMIP) runs with the ensemble simulations (SIMUs) ...

Kingtse C. Mo; J. E. Schemm; H. Kim; W. R. Higgins

2006-08-01T23:59:59.000Z

465

The Use of Equivalent Potential Vorticity to Diagnose Regions of Conditional Symmetric Instability  

Science Conference Proceedings (OSTI)

Conditional symmetric instability (CSI) is an important property of the atmosphere when diagnosing and predicting mesoscale bands of moderate to heavy precipitation within winter cyclones. Within regions of CSI, slantwise convection can increase ...

James T. Moore; Thomas E. Lambert

1993-09-01T23:59:59.000Z

466

Human effects on the global atmosphere  

SciTech Connect

This review considers whether human activities can significantly change important functions of the global atmosphere by altering the amount or distribution of certain trace species. It deals with three specific topics: stratopheric ozone, the role of species other than carbon dioxide on the greenhouse effect, and certain recently recognized atmospheric consequences of a large scale nuclear war. 64 references, 10 figures, 2 tables.

Johnston, H.S.

1984-01-01T23:59:59.000Z

467

Overwater Atmospheric Diffusion: Measurements and Parameterization  

Science Conference Proceedings (OSTI)

A series of ten atmospheric tracer experiments provided 62 hours of overwater atmospheric dispersion data. Sulfur hexafluoride (SF6) was released as the tracer gas at a height of 13 m from a ship positioned about 7 km off the central California ...

Walter F. Dabberdt

1986-08-01T23:59:59.000Z

468

Measurements of Atmospheric Nanoparticles (1875–1980)  

Science Conference Proceedings (OSTI)

The atmosphere contains a large variety of particles, ranging in size from near molecular (~1 nm) to larger than 10,000 nm. The total number concentration N of particles is dominated by nanoparticles ? 100 nm in diameter. Discovery of atmospheric ...

Volker Mohnen; George M. Hidy

2010-11-01T23:59:59.000Z

469

Mechanics of Light Weight Proppants: A Discrete Approach  

E-Print Network (OSTI)

Proppants are a specific application of granular materials used in oil/gas well stimulation. Employment of hard and soft particle mixtures is one of the many approaches availed by the industry to improve fracture resistance and the stability of the granular pack in the hydraulic fracture. Current industrial practices of proppant characterization involve long term and expensive conductivity tests. However, the mechanics governing the proppant pack response, in particular the effects due to material, shape and size of particles on the pack porosity, stiffness and particle fragmentation are not understood clearly. The present research embodies analytical and experimental approach to model hard (ceramic) and soft (walnut shell and/or pure aluminum) proppant mixtures by taking into account polydispersity in size, shape and material type of individual particles. The hydraulic fracture condition is represented through confined compression and flowback loads. The particle interactions clearly illustrate changes in pore space as a function of pressure, mixture composition and friction. Single particle compression tests on individual particles are carried out to obtain mechanical properties which are incorporated into the finite element models and are further correlated with the compression/crush response of the mixture. The proppant pack stiffness and particle fragmentation depends strongly on the mixture composition as illustrated in the models and experiments. The flowback models demonstrated that the formation of a stable arch is essential to pack stability. Additional variables that enhance flowback resistance are identified as: addition of softer particles to a pack, softer rock surfaces and higher inter-particle friction. The computational studies also led to the discovery of better, and more efficient pack compositions such as - short and thin pure Al needles/ceramic and the pistachio shells/ceramic mixtures. These analytical results have generated great interest and are engaged in the design of experiments to formulate future proppant pack mixtures at Baker Hughes Pressure Pumping, Tomball, TX.

Kulkarni, Mandar

2012-05-01T23:59:59.000Z

470

Modern Records of Atmospheric Nitrous Oxide (N2O) and a 2000-year Ice-core  

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

Modern Records of Atmospheric Nitrous Oxide (N2O) and a 2000-year Ice-core Modern Records of Atmospheric Nitrous Oxide (N2O) and a 2000-year Ice-core Record from Law Dome, Antarctica Introduction This page provides an introduction and links to records of atmospheric nitrous oxide (N2O) over the last 2000 years, emphasizing large data bases each representing currently active stations. Records in recent decades (time period depending on location) have been obtained from samples of ambient-air at remote locations, which represent changing global atmospheric conditions rather than influences of local sources. The longer (2000-year) record is from the Law Dome ice core in Antarctica. The ice-core record has been merged with modern annual data from Cape Grim, Tasmania to provide a 2000-year time series of annual values. A spline function has been fit to the data to provide a continuous time series of

471

THE FACILITY 350 HELIUM-ATMOSPHERE SYSTEM. Final Report, Metallurgy Division Program 1.5.5  

SciTech Connect

The He atmosphere system in Argonne's Facility 350 is described in detail. The system is straightforward, employing drying and carbon towers for the removal of moisture, oxygen, and other impurities. The bulk of the 15,000 ft/ sup 3/ of He atmosphere is continuously recirculated at nearly atmospheric pressure. Purification is accomplished at 140 psig on a portion of the gas that is passed through the drying tower at room temperature and the carbon towers at -- 46 deg C (--50 deg F). The operation is continuous, requiring a minimum of maintenance and operational manpower. The He atmosphere is supplied to the glove- boxes with impurity levels below 3,000 ppm nitrogen, 1,000 ppm oxygen, and 50 ppm moisture. Such purity levels prevent oxidation and combustion of the Pu materials being processed. Experimental data concerning the adsorption of oxygen from He by activated carbon over a range of temperature and pressure conditions are reported. (auth)

Mayfield, R.M.; Tope, W.G.; Shuck, A.B.

1962-12-01T23:59:59.000Z

472

Earth's early atmosphere  

SciTech Connect

Ideas about atmospheric composition and climate on the early Earth have evolved considerably over the last 30 years, but many uncertainties still remain. It is generally agreed that the atmosphere contained little or no free oxygen initially and that oxygen concentrations increased markely near 2.0 billion years ago, but the precise timing of and reasons for its rise remain unexplained. Likewise, it is usually conceded that the atmospheric greenhouse effect must have been higher in the past to offset reduced solar luminosity, but the levels of atmospheric carbon cioxide and other greenhouse gases required remain speculative. A better understanding of past atmospheric evolution is important to understanding the evolution of life and to predicting whether Earth-like planets might exist elsewhere in the galaxy.

Kasting, J.F. (Pennsylvania State Univ., University Park (United States))

1993-02-12T23:59:59.000Z

473

Efficient parallel architecture for multi-level forward discrete wavelet transform processors  

Science Conference Proceedings (OSTI)

A resource efficient and high-performance architecture for a two-dimensional multi-level discrete wavelet transform processor is presented in this paper. The JPEG2000 standard integer lossless 5-3 filter has been implemented. It achieves optimal hardware ...

Syed Mahfuzul Aziz; Duc Minh Pham

2012-09-01T23:59:59.000Z

474

Solving Hard Satisfiability Problems: A Unified Algorithm Based on Discrete Lagrange Multipliers  

Science Conference Proceedings (OSTI)

In this paper, we present improved strategies in DLM-99-SAT to escape from traps and to select proper parameter sets to use when applied to solve some difficult but satisfiable SAT problems. One of the main issues in DLM-99-SAT is that it has a large ... Keywords: DIMACS benchmarks, discrete Lagrange-multiplier method, first-order search procedure, satisfiability, traps

Zhe Wu; Benjamin W. Wah

1999-11-01T23:59:59.000Z

475

A test for second order stationarity of a time series based on the Discrete Fourier Transform  

E-Print Network (OSTI)

A test for second order stationarity of a time series based on the Discrete Fourier Transform property, we construct a Portmanteau type test statistic for testing stationarity of the time series. It is shown that under the null of stationarity, the test statistic is approximately a chi square distribution

Subba Rao, Suhasini

476

Sequential Monte Carlo for Bayesian sequentially designed experiments for discrete data  

Science Conference Proceedings (OSTI)

In this paper we present a sequential Monte Carlo algorithm for Bayesian sequential experimental design applied to generalised non-linear models for discrete data. The approach is computationally convenient in that the information of newly observed data ... Keywords: Clinical trials, Generalised linear model, Generalised non-linear model, Sequential Monte Carlo, Sequential design, Target stimulus

Christopher C. Drovandi; James M. Mcgree; Anthony N. Pettitt

2013-01-01T23:59:59.000Z

477

A general theory of connectivity and current sheets in coronal magnetic fields anchored to discrete sources  

E-Print Network (OSTI)

A general theory of connectivity and current sheets in coronal magnetic fields anchored to discrete are current-free within each domain, and contain singular currents along each of the field's separators. 1 suggested, from reconnection along the single field line lying at the interface of the four resulting flux

Longcope, Dana

478

A GENERAL THEORY OF CONNECTIVITY AND CURRENT SHEETS IN CORONAL MAGNETIC FIELDS ANCHORED TO DISCRETE SOURCES  

E-Print Network (OSTI)

A GENERAL THEORY OF CONNECTIVITY AND CURRENT SHEETS IN CORONAL MAGNETIC FIELDS ANCHORED TO DISCRETE on the flux of each domain. The resulting equilibria are current-free within each domain and contain singular currents along each of the field's separators. Subject headings: MHD -- Sun: corona -- Sun: magnetic fields

Klapper, Isaac

479

GPU accelerated simulations of 3D deterministic particle transport using discrete ordinates method  

Science Conference Proceedings (OSTI)

Graphics Processing Unit (GPU), originally developed for real-time, high-definition 3D graphics in computer games, now provides great faculty in solving scientific applications. The basis of particle transport simulation is the time-dependent, multi-group, ... Keywords: CUDA, Discrete ordinates (Sn) method, GPU, Particle transport, Sweep3D

Chunye Gong; Jie Liu; Lihua Chi; Haowei Huang; Jingyue Fang; Zhenghu Gong

2011-07-01T23:59:59.000Z

480

Brief paper: Discrete-time drift counteraction stochastic optimal control: Theory and application-motivated examples  

Science Conference Proceedings (OSTI)

We develop stochastic optimal control results for nonlinear discrete-time systems driven by disturbances modeled by a Markov chain. A characterization and a computational procedure for a control law which maximizes a cost functional, related to expected ... Keywords: Automotive applications, Constrained systems, Dynamic programming, Hybrid electric vehicles, Stochastic control

I. V. Kolmanovsky; L. Lezhnev; T. L. Maizenberg

2008-01-01T23:59:59.000Z

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481

Towards a discretely actuated steerable cannula for diagnostic and therapeutic procedures  

Science Conference Proceedings (OSTI)

We have designed, developed, and evaluated the performance of a multi-degree-of-freedom discretely actuated steerable cannula with shape-memory alloy (SMA) actuators. This will enable us to deliver diagnostic as well as therapeutic devices to the target ... Keywords: Medical robots and systems, design and control, human-centered and life-like robotics, mechanics, motion control, smart actuators

Elif Ayvali; Chia-Pin Liang; Mingyen Ho; Yu Chen; Jaydev P Desai

2012-04-01T23:59:59.000Z

482

Implicit--explicit methods based on strong stability preserving multistep time discretizations  

Science Conference Proceedings (OSTI)

In this note we propose and analyze novel implicit-explicit methods based on second order strong stability preserving multistep time discretizations. Several schemes are developed, and a linear stability analysis is performed to study their properties ... Keywords: Advection--diffusion equation, Implicit--explicit methods, Stability, Strong stability preserving methods

Thor Gjesdal

2007-08-01T23:59:59.000Z

483

Dynamic programming for constrained optimal control of discrete-time linear hybrid systems  

Science Conference Proceedings (OSTI)

In this paper we study the solution to optimal control problems for constrained discrete-time linear hybrid systems based on quadratic or linear performance criteria. The aim of the paper is twofold. First, we give basic theoretical results on the structure ... Keywords: Dynamic programming, Hybrid systems, Multiparametric programming, Optimal control, Piecewise affine systems

Francesco Borrelli; Mato Baoti?; Alberto Bemporad; Manfred Morari

2005-10-01T23:59:59.000Z

484

A Tight Lower Bound to the Outage Probability of Discrete-Input Block-Fading Channels  

Science Conference Proceedings (OSTI)

In this correspondence, a tight lower bound to the outage probability of discrete-input Nakagami-m block-fading channels is proposed. The approach permits an efficient method for numerical evaluation of the bound, providing an additional tool for system ... Keywords: Block-fading channel, diversity, error probability, outage probability, rate-diversity tradeoff, signal-to-noise ratio (SNR)-exponent

K. D. Nguyen; A. Guillen i Fabregas; L. K. Rasmussen

2007-11-01T23:59:59.000Z

485

Development of discrete event system specification (DEVS) building performance models for building energy design  

Science Conference Proceedings (OSTI)

The discrete event system specification (DEVS) is a formalism for describing simulation models in a modular fashion. In this study, it is exploited by forming submodels that allow different professions involved in the building design process to work ... Keywords: DEVS, energy simulation in building design, modular BPS, stochastic occupant models

Huseyin Burak Gunay; Liam O'Brien; Rhys Goldstein; Simon Breslav; Azam Khan

2013-04-01T23:59:59.000Z

486

Enhanced discrete differential evolution to determine optimal coordination of directional overcurrent relays in a power system  

Science Conference Proceedings (OSTI)

This paper presents an enhanced differential evolution technique to solve the optimal coordination of directional overcurrent relays in a power system. The most vital task when installing directional relays on the system is selecting suitable current ... Keywords: directional overcurrent relays (DOCRs), enhanced discrete differential evolution algorithm (EDDEA), pickup current settings (Ip), relay coordination, time dial settings (TDS)

Joymala Moirangthem; Subranshu Sekhar Dash; Bijaya Ketan Panigrahi

2011-12-01T23:59:59.000Z

487

Original article: Using the continuous price as control variate for discretely monitored options  

Science Conference Proceedings (OSTI)

Variance reduction is of highest importance in financial simulation. In this study, we present a new and simple variance reduction technique for pricing discretely monitored lookback and barrier options. It is based on using the corresponding continuously ... Keywords: Control variate, Option pricing, Path dependent options, Variance reduction

Kemal Dinçer Dingeç; Wolfgang Hörmann

2011-12-01T23:59:59.000Z

488

Generation and evaluation of orthogonal polynomials in discrete Sobolev spaces II: numerical stability  

Science Conference Proceedings (OSTI)

In this paper, we concern ourselves with the determination and evaluation of polynomials that are orthogonal with respect to a general discrete Sobolev inner product, that is, an ordinary inner product on the real line plus a finite sum of atomic inner ... Keywords: 42C10, 65D20, 65G50, Recurrence relations, Rounding errors, Sobolev orthogonal polynomials

R. Barrio; S. Serrano

2005-09-01T23:59:59.000Z

489

Automated synthesis of discrete-time sigma-delta modulators from system architecture to circuit netlist  

Science Conference Proceedings (OSTI)

A synthesis tool consisting of coefficient synthesis of architecture, circuit specifications synthesis, and CMOS operational-amplifier (op-amp) synthesis for discrete-time sigma-delta modulators (SDMs) is presented. In circuit specifications synthesis, ... Keywords: Automated synthesis, Behavioral modeling, Geometric programming, Op-amp synthesis, Sigma-delta modulator, Transistor sizing

Shuenn-Yuh Lee; Chih-Yuan Chen; Jia-Hua Hong; Rong-Guey Chang; Mark Po-Hung Lin

2011-02-01T23:59:59.000Z

490

Effects of size, shape, crystal plane and atomic discrete structure on interactions between carbon nanoparticles  

Science Conference Proceedings (OSTI)

Understanding various interaction forces between building blocks is of great importance to their selfassembly. In this paper, the effects of size, crystal plane, shape and atomic discrete structure on interaction potentials between carbon nanoparticles ... Keywords: Hamaker approach, carbon, interaction, molecular dynamics simulation, nanoparticle

Weifu Sun; Qinghua Zeng; Aibing Yu

2012-02-01T23:59:59.000Z

491

Threshold Levels for Nonstochastic Skin Effects From Low Energy Discrete Radioactive Particles  

Science Conference Proceedings (OSTI)

Assessment of risk from skin contamination by low-energy discrete radioactive particles (DRPs) is difficult because the particles produce nonuniform external radiation exposures. This study, which provides data on the relationship between DRP dose to the skin and biological skin response, can form the technical basis for developing regulations for controlling exposures.

1992-04-01T23:59:59.000Z

492

Defining the integers in expansions of the real field by a closed discrete set  

E-Print Network (OSTI)

Let $D\\subseteq \\mathbb{R}$ be closed and discrete and $f:D^n \\to \\mathbb{R}$ be such that $f(D^n)$ is somewhere dense. We show that $(\\mathbb{R},+,\\cdot,f)$ defines $\\mathbb{Z}$. As an application, we get that for every $\\alpha,\\beta \\in \\mathbb{R}$ with $\\log_{\\alpha}(\\beta)\

Hieronymi, Philipp

2009-01-01T23:59:59.000Z

493

Capacitance: A property of nanoscale materials based on spatial symmetry of discrete electrons  

Science Conference Proceedings (OSTI)

Capacitance is a measure of the ability to store electrons and is conventionally considered to be a constant dependent upon the shape of metal contacts and the dimensions of the system. In general, however, equipotentials of dielectric systems without ... Keywords: Capacitance, Discrete charges, Nanoscale materials, Periodic table

Tim LaFave, Jr.; Raphael Tsu

2008-03-01T23:59:59.000Z

494

A direct matrix method for computing analytical Jacobians of discretized nonlinear integro-differential equations  

Science Conference Proceedings (OSTI)

In this article, we present a simple direct matrix method for analytically computing the Jacobian of nonlinear algebraic equations that arise from the discretization of nonlinear integro-differential equations. The method is based on a formulation of ... Keywords: Analytical Jacobian, Integro-differential equations, Matrix calculus, Newton's method, Numerical methods

Kevin T. Chu

2009-08-01T23:59:59.000Z

495

Discrete Particle Swarm Optimization for the Multi-Level Lot-Sizing Problem  

Science Conference Proceedings (OSTI)

This paper presents a Discrete Particle Swarm Optimization (DPSO) approach for the Multi-Level Lot-Sizing Problem (MLLP), which is an uncapacitated lot sizing problem dedicated to materials requirements planning (MRP) systems. The proposed DPSO approach ... Keywords: DPSO, MLLP, MRP, Metaheuristic, Sequential Heuristic

Laurent Deroussi; David Lemoine

2011-01-01T23:59:59.000Z

496

Discrete Event Front-tracking Simulation of a Physical Fire-spread Model  

Science Conference Proceedings (OSTI)

Simulation of moving interfaces such as a fire front usually requires resolution of a large-scale and detailed domain. Such computing involves the use of supercomputers to process the large amount of data and calculations. This limitation is mainly due ... Keywords: DEVS, asynchronous, discrete events, envelope, fire spread, flame, forest, front tracking, interface, simulation

Jean-Baptiste Filippi; Frédéric Morandini; Jacques Henri Balbi; David Rc Hill

2010-10-01T23:59:59.000Z

497

To appear in the ACM SIGGRAPH conference proceedings Discrete Viscous Threads  

E-Print Network (OSTI)

To appear in the ACM SIGGRAPH conference proceedings Discrete Viscous Threads Mikl´os Bergou used in baby diapers, bandages, envelopes, upholstery, air ("HEPA") filters, surgical gowns, high in the ACM SIGGRAPH conference proceedings Figure 2: Using a time-parallel reference frame enables our

Wardetzky, Max

498

Abstract--In this paper, we propose an overall optimization of discrete multi-tone transmissions  

E-Print Network (OSTI)

-- Discrete Multi-tone; Polymer Optical Fiber; Light Emitting Diode; System Optimization; Bit-linearity phenomenon in resonant cavity light emitting diode (RC-LED) causes distortions to DMT signals [19 emitting diode (RC-LED) dynamic non-linearity performance, and analog-to-digital converters effective

Recanati, Catherine

499

Efficient discrete-time simulations of continuous-time quantum query algorithms  

E-Print Network (OSTI)

The continuous-time query model is a variant of the discrete query model in which queries can be interleaved with known operations (called "driving operations") continuously in time. Interesting algorithms have been discovered in this model, such as an algorithm for evaluating nand trees more efficiently than any classical algorithm. Subsequent work has shown that there also exists an efficient algorithm for nand trees in the discrete query model; however, there is no efficient conversion known for continuous-time query algorithms for arbitrary problems. We show that any quantum algorithm in the continuous-time query model whose total query time is T can be simulated by a quantum algorithm in the discrete query model that makes O[T log(T) / log(log(T))] queries. This is the first upper bound that is independent of the driving operations (i.e., it holds even if the norm of the driving Hamiltonian is very large). A corollary is that any lower bound of T queries for a problem in the discrete-time query model immediately carries over to a lower bound of \\Omega[T log(log(T))/log (T)] in the continuous-time query model.

R. Cleve; D. Gottesman; M. Mosca; R. D. Somma; D. L. Yonge-Mallo

2008-11-26T23:59:59.000Z

500

Finite Element Analysis of a Composite Semi-Span Test Article With and Without Discrete Damage  

Science Conference Proceedings (OSTI)

AS&M, Inc. performed finite element analysis, with and without discrete damage, of a composite semi-span test article that represents the Boeing 220-passenger transport aircraft composite semi-span test article. A NASTRAN bulk data file and drawings ...

Lovejoy Andrew E.

2000-08-01T23:59:59.000Z