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1

An Analysis Platform for Multiscale Hydrogeologic Modeling with Emphasis on Hybrid Multiscale Methods  

SciTech Connect (OSTI)

One of the most significant challenges facing hydrogeologic modelers is the disparity between those spatial and temporal scales at which fundamental flow, transport and reaction processes can best be understood and quantified (e.g., microscopic to pore scales, seconds to days) and those at which practical model predictions are needed (e.g., plume to aquifer scales, years to centuries). While the multiscale nature of hydrogeologic problems is widely recognized, technological limitations in computational and characterization restrict most practical modeling efforts to fairly coarse representations of heterogeneous properties and processes. For some modern problems, the necessary level of simplification is such that model parameters may lose physical meaning and model predictive ability is questionable for any conditions other than those to which the model was calibrated. Recently, there has been broad interest across a wide range of scientific and engineering disciplines in simulation approaches that more rigorously account for the multiscale nature of systems of interest. In this paper, we review a number of such approaches and propose a classification scheme for defining different types of multiscale simulation methods and those classes of problems to which they are most applicable. Our classification scheme is presented in terms of a flow chart (Multiscale Analysis Platform or MAP), and defines several different motifs of multiscale simulation. Within each motif, the member methods are reviewed and example applications are discussed. We focus attention on hybrid multiscale methods, in which two or more models with different physics described at fundamentally different scales are directly coupled within a single simulation. Very recently these methods have begun to be applied to groundwater flow and transport simulations, and we discuss these applications in the context of our classification scheme. As computational and characterization capabilities continue to improve, we envision that hybrid multiscale modeling will become more common and may become a viable alternative to conventional single-scale models in the near future.

Scheibe, Timothy D.; Murphy, Ellyn M.; Chen, Xingyuan; Rice, Amy K.; Carroll, Kenneth C.; Palmer, Bruce J.; Tartakovsky, Alexandre M.; Battiato, Ilenia; Wood, Brian D.

2015-01-01T23:59:59.000Z

2

An Analysis Platform for Multiscale Hydrogeologic Modeling with...  

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

An Analysis Platform for Multiscale Hydrogeologic Modeling with Emphasis on Hybrid Multiscale Methods. An Analysis Platform for Multiscale Hydrogeologic Modeling with Emphasis on...

3

A mathematical framework for multiscale science and engineering : the variational multiscale method and interscale transfer operators.  

SciTech Connect (OSTI)

This report is a collection of documents written as part of the Laboratory Directed Research and Development (LDRD) project A Mathematical Framework for Multiscale Science and Engineering: The Variational Multiscale Method and Interscale Transfer Operators. We present developments in two categories of multiscale mathematics and analysis. The first, continuum-to-continuum (CtC) multiscale, includes problems that allow application of the same continuum model at all scales with the primary barrier to simulation being computing resources. The second, atomistic-to-continuum (AtC) multiscale, represents applications where detailed physics at the atomistic or molecular level must be simulated to resolve the small scales, but the effect on and coupling to the continuum level is frequently unclear.

Wagner, Gregory John (Sandia National Laboratories, Livermore, CA); Collis, Samuel Scott; Templeton, Jeremy Alan (Sandia National Laboratories, Livermore, CA); Lehoucq, Richard B.; Parks, Michael L.; Jones, Reese E. (Sandia National Laboratories, Livermore, CA); Silling, Stewart Andrew; Scovazzi, Guglielmo; Bochev, Pavel B.

2007-10-01T23:59:59.000Z

4

Multiscale Thermohydrologic Model  

SciTech Connect (OSTI)

The purpose of the multiscale thermohydrologic model (MSTHM) is to predict the possible range of thermal-hydrologic conditions, resulting from uncertainty and variability, in the repository emplacement drifts, including the invert, and in the adjoining host rock for the repository at Yucca Mountain. Thus, the goal is to predict the range of possible thermal-hydrologic conditions across the repository; this is quite different from predicting a single expected thermal-hydrologic response. The MSTHM calculates the following thermal-hydrologic parameters: temperature, relative humidity, liquid-phase saturation, evaporation rate, air-mass fraction, gas-phase pressure, capillary pressure, and liquid- and gas-phase fluxes (Table 1-1). These thermal-hydrologic parameters are required to support ''Total System Performance Assessment (TSPA) Model/Analysis for the License Application'' (BSC 2004 [DIRS 168504]). The thermal-hydrologic parameters are determined as a function of position along each of the emplacement drifts and as a function of waste package type. These parameters are determined at various reference locations within the emplacement drifts, including the waste package and drip-shield surfaces and in the invert. The parameters are also determined at various defined locations in the adjoining host rock. The MSTHM uses data obtained from the data tracking numbers (DTNs) listed in Table 4.1-1. The majority of those DTNs were generated from the following analyses and model reports: (1) ''UZ Flow Model and Submodels'' (BSC 2004 [DIRS 169861]); (2) ''Development of Numerical Grids for UZ Flow and Transport Modeling'' (BSC 2004); (3) ''Calibrated Properties Model'' (BSC 2004 [DIRS 169857]); (4) ''Thermal Conductivity of the Potential Repository Horizon'' (BSC 2004 [DIRS 169854]); (5) ''Thermal Conductivity of the Non-Repository Lithostratigraphic Layers'' (BSC 2004 [DIRS 170033]); (6) ''Ventilation Model and Analysis Report'' (BSC 2004 [DIRS 169862]); (7) ''Heat Capacity Analysis Report'' (BSC 2004 [DIRS 170003]).

T. Buscheck

2004-10-12T23:59:59.000Z

5

Numerical Stochastic Homogenization Method and Multiscale Stochastic Finite Element Method - A Paradigm for Multiscale Computation of Stochastic PDEs  

SciTech Connect (OSTI)

Multiscale modeling of stochastic systems, or uncertainty quantization of multiscale modeling is becoming an emerging research frontier, with rapidly growing engineering applications in nanotechnology, biotechnology, advanced materials, and geo-systems, etc. While tremendous efforts have been devoted to either stochastic methods or multiscale methods, little combined work had been done on integration of multiscale and stochastic methods, and there was no method formally available to tackle multiscale problems involving uncertainties. By developing an innovative Multiscale Stochastic Finite Element Method (MSFEM), this research has made a ground-breaking contribution to the emerging field of Multiscale Stochastic Modeling (MSM) (Fig 1). The theory of MSFEM basically decomposes a boundary value problem of random microstructure into a slow scale deterministic problem and a fast scale stochastic one. The slow scale problem corresponds to common engineering modeling practices where fine-scale microstructure is approximated by certain effective constitutive constants, which can be solved by using standard numerical solvers. The fast scale problem evaluates fluctuations of local quantities due to random microstructure, which is important for scale-coupling systems and particularly those involving failure mechanisms. The Green-function-based fast-scale solver developed in this research overcomes the curse-of-dimensionality commonly met in conventional approaches, by proposing a random field-based orthogonal expansion approach. The MSFEM formulated in this project paves the way to deliver the first computational tool/software on uncertainty quantification of multiscale systems. The applications of MSFEM on engineering problems will directly enhance our modeling capability on materials science (composite materials, nanostructures), geophysics (porous media, earthquake), biological systems (biological tissues, bones, protein folding). Continuous development of MSFEM will further contribute to the establishment of Multiscale Stochastic Modeling strategy, and thereby potentially to bring paradigm-shifting changes to simulation and modeling of complex systems cutting across multidisciplinary fields.

X. Frank Xu

2010-03-30T23:59:59.000Z

6

Multiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation Response Effects of Radiation Quality and HypoxiaEffects of Radiation Quality and Hypoxia  

E-Print Network [OSTI]

Multiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation Response Effects of Radiation Quality and HypoxiaEffects of Radiation Quality and Hypoxia Robert D. Stewart, Ph.D.Robert D. Stewart, Ph

Stewart, Robert D.

7

Towards a Multiscale Approach to Cybersecurity Modeling  

SciTech Connect (OSTI)

We propose a multiscale approach to modeling cyber networks, with the goal of capturing a view of the network and overall situational awareness with respect to a few key properties--- connectivity, distance, and centrality--- for a system under an active attack. We focus on theoretical and algorithmic foundations of multiscale graphs, coming from an algorithmic perspective, with the goal of modeling cyber system defense as a specific use case scenario. We first define a notion of \\emph{multiscale} graphs, in contrast with their well-studied single-scale counterparts. We develop multiscale analogs of paths and distance metrics. As a simple, motivating example of a common metric, we present a multiscale analog of the all-pairs shortest-path problem, along with a multiscale analog of a well-known algorithm which solves it. From a cyber defense perspective, this metric might be used to model the distance from an attacker's position in the network to a sensitive machine. In addition, we investigate probabilistic models of connectivity. These models exploit the hierarchy to quantify the likelihood that sensitive targets might be reachable from compromised nodes. We believe that our novel multiscale approach to modeling cyber-physical systems will advance several aspects of cyber defense, specifically allowing for a more efficient and agile approach to defending these systems.

Hogan, Emilie A.; Hui, Peter SY; Choudhury, Sutanay; Halappanavar, Mahantesh; Oler, Kiri J.; Joslyn, Cliff A.

2013-11-12T23:59:59.000Z

8

Multiscale Subsurface Biogeochemical Modeling Project at NERSC  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recovery challengeMultiscale Subsurface Biogeochemical Modeling Multiscale Subsurface

9

MULTISCALE MODELING OF THE RESPIRATORY TRACT  

E-Print Network [OSTI]

correspond to di®erent mechanical models. The resulting system is described by the NavierÀStokes equation of the respiratory tree into three stages where di®erent models will be exploited and in which the mechanicalMULTISCALE MODELING OF THE RESPIRATORY TRACT LEONARDO BAFFICO Laboratoire de Mathematiques N

Maury, Bertrand

10

Final Report for Integrated Multiscale Modeling of Molecular Computing Devices  

SciTech Connect (OSTI)

In collaboration with researchers at Vanderbilt University, North Carolina State University, Princeton and Oakridge National Laboratory we developed multiscale modeling and simulation methods capable of modeling the synthesis, assembly, and operation of molecular electronics devices. Our role in this project included the development of coarse-grained molecular and mesoscale models and simulation methods capable of simulating the assembly of millions of organic conducting molecules and other molecular components into nanowires, crossbars, and other organized patterns.

Glotzer, Sharon C.

2013-08-28T23:59:59.000Z

11

Multiscale modeling of spatially variable water and energy balance processes  

E-Print Network [OSTI]

MULTISCALE WATER AND ENERGY BALANCE MODELING Wood, E. F. ,spatially variable water and energy balance processes J. S.modeling. Water and energy balance models are developed at

Famiglietti, J. S; Wood, E. F

1994-01-01T23:59:59.000Z

12

Multiscale Agent-Based Consumer Market Modeling  

E-Print Network [OSTI]

, and Visualization Group; and 3 Center for Energy, Environmental, and Economic Systems Analysis, Argonne NationalMultiscale Agent-Based Consumer Market Modeling MICHAEL J. NORTH,1 CHARLES M. MACAL,1 JAMES ST 8, 2009; revised August 19, 2009; accepted September 8, 2009 Consumer markets have been studied

Kemner, Ken

13

Uncertainty quantification using multiscale methods for porous media flows  

E-Print Network [OSTI]

numerical models. When solving the flow and transport through heterogeneous porous media some type of upscaling or coarsening is needed due to scale disparity. We describe multiscale techniques used for solving the spatial component of the stochastic flow...

Dostert, Paul Francis

2009-05-15T23:59:59.000Z

14

Optimization Online - A stochastic multiscale model for electricity ...  

E-Print Network [OSTI]

May 30, 2011 ... A stochastic multiscale model for electricity generation capacity expansion. Panos Parpas(pparpas ***at*** mit.edu) Mort Webster(mort ***at*** ...

Panos Parpas

2011-05-30T23:59:59.000Z

15

Multiscale modeling in granular flow  

E-Print Network [OSTI]

Granular materials are common in everyday experience, but have long-resisted a complete theoretical description. Here, we consider the regime of slow, dense granular flow, for which there is no general model, representing ...

Rycroft, Christopher Harley

2007-01-01T23:59:59.000Z

16

Multiscale Modeling with Carbon Nanotubes  

SciTech Connect (OSTI)

Technologically important nanomaterials come in all shapes and sizes. They can range from small molecules to complex composites and mixtures. Depending upon the spatial dimensions of the system and properties under investigation computer modeling of such materials can range from equilibrium and nonequilibrium Quantum Mechanics, to force-field-based Molecular Mechanics and kinetic Monte Carlo, to Mesoscale simulation of evolving morphology, to Finite-Element computation of physical properties. This brief review illustrates some of the above modeling techniques through a number of recent applications with carbon nanotubes: nano electromechanical sensors (NEMS), chemical sensors, metal-nanotube contacts, and polymer-nanotube composites.

Maiti, A

2006-02-21T23:59:59.000Z

17

A Posteriori Analysis of Adaptive Multiscale Operator Decomposition Methods for Multiphysics Problems  

SciTech Connect (OSTI)

This project was concerned with the accurate computational error estimation for numerical solutions of multiphysics, multiscale systems that couple different physical processes acting across a large range of scales relevant to the interests of the DOE. Multiscale, multiphysics models are characterized by intimate interactions between different physics across a wide range of scales. This poses significant computational challenges addressed by the proposal, including: (1) Accurate and efficient computation; (2) Complex stability; and (3) Linking different physics. The research in this project focused on Multiscale Operator Decomposition methods for solving multiphysics problems. The general approach is to decompose a multiphysics problem into components involving simpler physics over a relatively limited range of scales, and then to seek the solution of the entire system through some sort of iterative procedure involving solutions of the individual components. MOD is a very widely used technique for solving multiphysics, multiscale problems; it is heavily used throughout the DOE computational landscape. This project made a major advance in the analysis of the solution of multiscale, multiphysics problems.

Donald Estep; Michael Holst; Simon Tavener

2010-02-08T23:59:59.000Z

18

Modeling complex biological flows in multi-scale systems using the APDEC framework  

E-Print Network [OSTI]

Modeling complex biological flows in multi-scale systems using the APDEC framework David Trebotich methods are based on higher-order finite difference methods in complex geometry with adaptivity-mail: trebotich1@llnl.gov Abstract. We have developed advanced numerical algorithms to model biological fluids

19

Multiscale modeling of polyisoprene on graphite  

SciTech Connect (OSTI)

The local dynamics and the conformational properties of polyisoprene next to a smooth graphite surface constructed by graphene layers are studied by a multiscale methodology. First, fully atomistic molecular dynamics simulations of oligomers next to the surface are performed. Subsequently, Monte Carlo simulations of a systematically derived coarse-grained model generate numerous uncorrelated structures for polymer systems. A new reverse backmapping strategy is presented that reintroduces atomistic detail. Finally, multiple extensive fully atomistic simulations with large systems of long macromolecules are employed to examine local dynamics in proximity to graphite. Polyisoprene repeat units arrange close to a parallel configuration with chains exhibiting a distribution of contact lengths. Efficient Monte Carlo algorithms with the coarse-grain model are capable of sampling these distributions for any molecular weight in quantitative agreement with predictions from atomistic models. Furthermore, molecular dynamics simulations with well-equilibrated systems at all length-scales support an increased dynamic heterogeneity that is emerging from both intermolecular interactions with the flat surface and intramolecular cooperativity. This study provides a detailed comprehensive picture of polyisoprene on a flat surface and consists of an effort to characterize such systems in atomistic detail.

Pandey, Yogendra Narayan; Brayton, Alexander; Doxastakis, Manolis, E-mail: edoxastakis@uh.edu [Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204 (United States)] [Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204 (United States); Burkhart, Craig; Papakonstantopoulos, George J. [Global Materials Science Division, The Goodyear Tire and Rubber Company, Akron, Ohio 44305 (United States)] [Global Materials Science Division, The Goodyear Tire and Rubber Company, Akron, Ohio 44305 (United States)

2014-02-07T23:59:59.000Z

20

A dynamic multi-scale model for transient radiative transfer calculations  

E-Print Network [OSTI]

on the radiative transfer equation (RTE) or the diffusion equation (DE). The RTE is a kinetic transport equation-scale model which couples the transient radiative transfer equation (RTE) and the diffusion equation (DE: transient radiative transfer, multi-scale model, finite volume method, diffusion equation, domain

Boyer, Edmond

Note: This page contains sample records for the topic "method multiscale modeling" 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

Fast multiscale Gaussian beam methods for wave equations in bounded convex domains  

SciTech Connect (OSTI)

Motivated by fast multiscale Gaussian wavepacket transforms and multiscale Gaussian beam methods which were originally designed for pure initial-value problems of wave equations, we develop fast multiscale Gaussian beam methods for initial boundary value problems of wave equations in bounded convex domains in the high frequency regime. To compute the wave propagation in bounded convex domains, we have to take into account reflecting multiscale Gaussian beams, which are accomplished by enforcing reflecting boundary conditions during beam propagation and carrying out suitable reflecting beam summation. To propagate multiscale beams efficiently, we prove that the ratio of the squared magnitude of beam amplitude and the beam width is roughly conserved, and accordingly we propose an effective indicator to identify significant beams. We also prove that the resulting multiscale Gaussian beam methods converge asymptotically. Numerical examples demonstrate the accuracy and efficiency of the method.

Bao, Gang, E-mail: bao@math.msu.edu [Department of Mathematics, Zhejiang University, Hangzhou 310027 (China) [Department of Mathematics, Zhejiang University, Hangzhou 310027 (China); Department of Mathematics, Michigan State University, East Lansing, MI 48824 (United States); Lai, Jun, E-mail: laijun@msu.edu [Department of Mathematics, Michigan State University, East Lansing, MI 48824 (United States)] [Department of Mathematics, Michigan State University, East Lansing, MI 48824 (United States); Qian, Jianliang, E-mail: qian@math.msu.edu [Department of Mathematics, Michigan State University, East Lansing, MI 48824 (United States)] [Department of Mathematics, Michigan State University, East Lansing, MI 48824 (United States)

2014-03-15T23:59:59.000Z

22

Multiscale modelling of the respiratory tract C. Grandmont  

E-Print Network [OSTI]

to different mechanical models. The resulting system is described by the Navier-Stokes equation coupledMultiscale modelling of the respiratory tract L. Baffico C. Grandmont B. Maury§ February 20, 2009 Abstract We propose here a decomposition of the respiratory tree into three stages which correspond

Paris-Sud XI, Université de

23

Finite element analysis of grain-matrix micro-cracking in shale within the context of a multiscale modeling  

E-Print Network [OSTI]

, hydrofracturing, or oil shale production. Current macro- scale and multiscale models do not account simultaneously

Regueiro, Richard A.

24

Sustainable Manufacturing via Multi-Scale, Physics-Based Process Modeling and Manufacturing-Informed Design, April 2013  

Broader source: Energy.gov [DOE]

Sustainable Manufacturing via Multi-Scale, Physics-Based Process Modeling and Manufacturing-Informed Design

25

Generalized finite element method for multiscale analysis  

E-Print Network [OSTI]

by the Partition of Unity Method (PUM). It is shown that the p-version of the Generalized FEM using mesh-based handbook functions is capable of achieving very high accuracy. It is also analyzed that the effect of the main factors affecting the accuracy...

Zhang, Lin

2004-11-15T23:59:59.000Z

26

The Local Variational Multiscale Method for Turbulence Simulation.  

SciTech Connect (OSTI)

Accurate and efficient turbulence simulation in complex geometries is a formidable chal-lenge. Traditional methods are often limited by low accuracy and/or restrictions to simplegeometries. We explore the merger of Discontinuous Galerkin (DG) spatial discretizationswith Variational Multi-Scale (VMS) modeling, termed Local VMS (LVMS), to overcomethese limitations. DG spatial discretizations support arbitrarily high-order accuracy on un-structured grids amenable for complex geometries. Furthermore, high-order, hierarchicalrepresentation within DG provides a natural framework fora prioriscale separation crucialfor VMS implementation. We show that the combined benefits of DG and VMS within theLVMS method leads to promising new approach to LES for use in complex geometries.The efficacy of LVMS for turbulence simulation is assessed by application to fully-developed turbulent channelflow. First, a detailed spatial resolution study is undertakento record the effects of the DG discretization on turbulence statistics. Here, the localhp[?]refinement capabilites of DG are exploited to obtain reliable low-order statistics effi-ciently. Likewise, resolution guidelines for simulating wall-bounded turbulence using DGare established. We also explore the influence of enforcing Dirichlet boundary conditionsindirectly through numericalfluxes in DG which allows the solution to jump (slip) at thechannel walls. These jumps are effective in simulating the influence of the wall commen-surate with the local resolution and this feature of DG is effective in mitigating near-wallresolution requirements. In particular, we show that by locally modifying the numericalviscousflux used at the wall, we are able to regulate the near-wall slip through a penaltythat leads to improved shear-stress predictions. This work, demonstrates the potential ofthe numerical viscousflux to act as a numerically consistent wall-model and this successwarrents future research.As in any high-order numerical method some mechanism is required to control aliasingeffects due to nonlinear interactions and to ensure nonlinear stability of the method. Inthis context, we evaluate the merits of two approaches to de-aliasing -- spectralfilteringand polynomial dealiasing. While both approaches are successful, polynomial-dealiasingis found to be better suited for use in large-eddy simulation. Finally, results using LVMSare reported and show good agreement with reference direct numerical simulation therebydemonstrating the effectiveness of LVMS for wall-bounded turbulence. This success pavesthe way for future applications of LVMS to more complex turbulentflows.3

Collis, Samuel Scott; Ramakrishnan, Srinivas

2005-05-01T23:59:59.000Z

27

Multiscale modeling of polystyrene dynamics in different environments  

E-Print Network [OSTI]

Multiscale modeling of polystyrene dynamics in different environments Qi Sun1 , Florence Pon1 simulations can address not only the average properties of the system but also the distribution over any component in their neighborhood and vice versa. The simulation temperature of 450 K is chosen to be above

Faller, Roland

28

MULTISCALE MODELING OF DIFFUSION-INDUCED DEFORMATION PROCESSES  

E-Print Network [OSTI]

MULTISCALE MODELING OF DIFFUSION- INDUCED DEFORMATION PROCESSES Dr. Eugene Olevsky Friday, February 19, 2010 Engineering Bldg. Room E 300 Sintering is a high temperature process of bonding together of matter transport by different diffusion mechanisms driven by the high surface energy of aggregates

Ponce, V. Miguel

29

Multiscale modeling of exocytosis in the fertilization process  

E-Print Network [OSTI]

We discuss the implementation of a multiscale biophysico-chemical model able to cope with the main mechanisms underlying cumulative exocytosis in cells. The model is based on a diffusion equation in the presence of external forces that links calcium signaling and the biochemistry associated to the activity of cytoskeletal-based protein motors. This multiscale model offers an excellent quantitative spatio-temporal description of the cumulative exocytosis measured by means of fluorescence experiments. We also review pre-existing models reported in the literature on calcium waves, protein motor activation and dynamics, and intracellular directed transport of vesicles. As an example of the proposed model, we analyze the formation of the shield against polyspermy in the early events of fertilization in sea urchin eggs.

Aldo Ledesma Duran; I. Santamaria-Holek

2015-02-23T23:59:59.000Z

30

Significant Enhancement of Computational Efficiency in Nonlinear Multiscale Battery Model for Computer Aided Engineering (Presentation)  

SciTech Connect (OSTI)

This presentation discusses the significant enhancement of computational efficiency in nonlinear multiscale battery model for computer aided engineering in current research at NREL.

Kim, G.; Pesaran, A.; Smith, K.; Graf, P.; Jun, M.; Yang, C.; Li, G.; Li, S.; Hochman, A.; Tselepidakis, D.; White, J.

2014-06-01T23:59:59.000Z

31

Multi-Scale Multi-Dimensional Model for Better Cell Design and Management (Presentation)  

SciTech Connect (OSTI)

Describes NREL's R&D to develop a multi-scale model to assist in designing better, more reliable lithium-ion battery cells for advanced vehicles.

Kim, G.-H.; Smith, K.

2008-09-01T23:59:59.000Z

32

Multi-scale problems, high performance computing and hybrid numerical methods  

E-Print Network [OSTI]

Multi-scale problems, high performance computing and hybrid numerical methods G. Balarac, G of High Performance Computing G. Balarac LEGI, CNRS and Universit´e de Grenoble, BP 53, 38041 Grenoble

Cottet, Georges-Henri

33

Multi-scale problems, high performance computing and hybrid numerical methods  

E-Print Network [OSTI]

Multi-scale problems, high performance computing and hybrid numerical methods G. Balarac, G of High Performance Computing (HPC) is not anymore restricted to academia and scientific grand challenges

Paris-Sud XI, Université de

34

Multiscale Method for Elastic Wave Propagation in the Heterogeneous, Anisotropic Media  

E-Print Network [OSTI]

FEM) for elastic wave propagation in heterogeneous, anisotropic media in both continuous Galerkin (CG) and discontinuous Galerkin (DG) formulations. The advantage of the multiscale basis functions is they are model-dependent, unlike the predefined polynomial basis...

Gao, Kai

2014-08-05T23:59:59.000Z

35

Multiscale modeling for fluid transport in nanosystems.  

SciTech Connect (OSTI)

Atomistic-scale behavior drives performance in many micro- and nano-fluidic systems, such as mircrofludic mixers and electrical energy storage devices. Bringing this information into the traditionally continuum models used for engineering analysis has proved challenging. This work describes one such approach to address this issue by developing atomistic-to-continuum multi scale and multi physics methods to enable molecular dynamics (MD) representations of atoms to incorporated into continuum simulations. Coupling is achieved by imposing constraints based on fluxes of conserved quantities between the two regions described by one of these models. The impact of electric fields and surface charges are also critical, hence, methodologies to extend finite-element (FE) MD electric field solvers have been derived to account for these effects. Finally, the continuum description can have inconsistencies with the coarse-grained MD dynamics, so FE equations based on MD statistics were derived to facilitate the multi scale coupling. Examples are shown relevant to nanofluidic systems, such as pore flow, Couette flow, and electric double layer.

Lee, Jonathan W.; Jones, Reese E.; Mandadapu, Kranthi Kiran; Templeton, Jeremy Alan; Zimmerman, Jonathan A.

2013-09-01T23:59:59.000Z

36

Multiscale Modeling and Homogenization of Composite Materials  

E-Print Network [OSTI]

integration schemes, conjugate gradient methods and sparsescheme known as the conjugate gradient method. The algorithmConjugate Gradient To solve the systems of equations that arise when you using the finite element method

Mseis, George

2010-01-01T23:59:59.000Z

37

Multiscale Sagebrush Rangeland Habitat Modeling in the Gunnison Basin of Colorado  

E-Print Network [OSTI]

Multiscale Sagebrush Rangeland Habitat Modeling in the Gunnison Basin of Colorado Open-File Report" in Gunnison Basin, Colorado, 2007 (photograph by Lorie Brummer, U.S. Geological Survey). #12;Multiscale Sagebrush Rangeland Habitat Modeling in the Gunnison Basin of Colorado By Collin G. Homer, Cameron L

Aldridge, Cameron

38

Multiscale models of atmospheric mercury: bromine chemistry, air-sea exchange, and global transport  

E-Print Network [OSTI]

entrainment of RGM-rich air from the free troposphere (25­40%). Oxidation of Hg0 by Cl is minor (3Multiscale models of atmospheric mercury: bromine chemistry, air-sea exchange, and global transport Multiscale models of atmospheric mercury: bromine chemistry, air-sea exchange, and global transport Abstract

Holmes, Christopher D.

39

Multiscale geometric modeling of macromolecules I: Cartesian representation  

SciTech Connect (OSTI)

This paper focuses on the geometric modeling and computational algorithm development of biomolecular structures from two data sources: Protein Data Bank (PDB) and Electron Microscopy Data Bank (EMDB) in the Eulerian (or Cartesian) representation. Molecular surface (MS) contains non-smooth geometric singularities, such as cusps, tips and self-intersecting facets, which often lead to computational instabilities in molecular simulations, and violate the physical principle of surface free energy minimization. Variational multiscale surface definitions are proposed based on geometric flows and solvation analysis of biomolecular systems. Our approach leads to geometric and potential driven Laplace–Beltrami flows for biomolecular surface evolution and formation. The resulting surfaces are free of geometric singularities and minimize the total free energy of the biomolecular system. High order partial differential equation (PDE)-based nonlinear filters are employed for EMDB data processing. We show the efficacy of this approach in feature-preserving noise reduction. After the construction of protein multiresolution surfaces, we explore the analysis and characterization of surface morphology by using a variety of curvature definitions. Apart from the classical Gaussian curvature and mean curvature, maximum curvature, minimum curvature, shape index, and curvedness are also applied to macromolecular surface analysis for the first time. Our curvature analysis is uniquely coupled to the analysis of electrostatic surface potential, which is a by-product of our variational multiscale solvation models. As an expository investigation, we particularly emphasize the numerical algorithms and computational protocols for practical applications of the above multiscale geometric models. Such information may otherwise be scattered over the vast literature on this topic. Based on the curvature and electrostatic analysis from our multiresolution surfaces, we introduce a new concept, the polarized curvature, for the prediction of protein binding sites.

Xia, Kelin [Department of Mathematics, Michigan State University, MI 48824 (United States)] [Department of Mathematics, Michigan State University, MI 48824 (United States); Feng, Xin [Department of Computer Science and Engineering, Michigan State University, MI 48824 (United States)] [Department of Computer Science and Engineering, Michigan State University, MI 48824 (United States); Chen, Zhan [Department of Mathematics, Michigan State University, MI 48824 (United States)] [Department of Mathematics, Michigan State University, MI 48824 (United States); Tong, Yiying [Department of Computer Science and Engineering, Michigan State University, MI 48824 (United States)] [Department of Computer Science and Engineering, Michigan State University, MI 48824 (United States); Wei, Guo-Wei, E-mail: wei@math.msu.edu [Department of Mathematics, Michigan State University, MI 48824 (United States) [Department of Mathematics, Michigan State University, MI 48824 (United States); Department of Biochemistry and Molecular Biology, Michigan State University, MI 48824 (United States)

2014-01-15T23:59:59.000Z

40

Multiscale multiphysics and multidomain models—Flexibility and rigidity  

SciTech Connect (OSTI)

The emerging complexity of large macromolecules has led to challenges in their full scale theoretical description and computer simulation. Multiscale multiphysics and multidomain models have been introduced to reduce the number of degrees of freedom while maintaining modeling accuracy and achieving computational efficiency. A total energy functional is constructed to put energies for polar and nonpolar solvation, chemical potential, fluid flow, molecular mechanics, and elastic dynamics on an equal footing. The variational principle is utilized to derive coupled governing equations for the above mentioned multiphysical descriptions. Among these governing equations is the Poisson-Boltzmann equation which describes continuum electrostatics with atomic charges. The present work introduces the theory of continuum elasticity with atomic rigidity (CEWAR). The essence of CEWAR is to formulate the shear modulus as a continuous function of atomic rigidity. As a result, the dynamics complexity of a macromolecular system is separated from its static complexity so that the more time-consuming dynamics is handled with continuum elasticity theory, while the less time-consuming static analysis is pursued with atomic approaches. We propose a simple method, flexibility-rigidity index (FRI), to analyze macromolecular flexibility and rigidity in atomic detail. The construction of FRI relies on the fundamental assumption that protein functions, such as flexibility, rigidity, and energy, are entirely determined by the structure of the protein and its environment, although the structure is in turn determined by all the interactions. As such, the FRI measures the topological connectivity of protein atoms or residues and characterizes the geometric compactness of the protein structure. As a consequence, the FRI does not resort to the interaction Hamiltonian and bypasses matrix diagonalization, which underpins most other flexibility analysis methods. FRI's computational complexity is of O(N{sup 2}) at most, where N is the number of atoms or residues, in contrast to O(N{sup 3}) for Hamiltonian based methods. We demonstrate that the proposed FRI gives rise to accurate prediction of protein B-Factor for a set of 263 proteins. We show that a parameter free FRI is able to achieve about 95% accuracy of the parameter optimized FRI. An interpolation algorithm is developed to construct continuous atomic flexibility functions for visualization and use with CEWAR.

Xia, Kelin [Department of Mathematics, Michigan State University, East Lansing, Michigan 48824 (United States)] [Department of Mathematics, Michigan State University, East Lansing, Michigan 48824 (United States); Opron, Kristopher [Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824 (United States)] [Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824 (United States); Wei, Guo-Wei, E-mail: wei@math.msu.edu [Department of Mathematics, Michigan State University, East Lansing, Michigan 48824 (United States) [Department of Mathematics, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824 (United States)

2013-11-21T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

Multiscale modeling of clay-water systems  

E-Print Network [OSTI]

The engineering properties of soils are highly affected by clay content and clay-water interactions. However, existing macro-scale continuum models have no length scale to describe the evolution of the clay microstructure ...

Ebrahimi, Davoud

2014-01-01T23:59:59.000Z

42

Multiscale Design of Advanced Materials based on Hybrid Ab Initio and Quasicontinuum Methods  

SciTech Connect (OSTI)

This project united researchers from mathematics, chemistry, computer science, and engineering for the development of new multiscale methods for the design of materials. Our approach was highly interdisciplinary, but it had two unifying themes: first, we utilized modern mathematical ideas about change-of-scale and state-of-the-art numerical analysis to develop computational methods and codes to solve real multiscale problems of DOE interest; and, second, we took very seriously the need for quantum mechanics-based atomistic forces, and based our methods on fast solvers of chemically accurate methods.

Luskin, Mitchell [University of Minnesota

2014-03-12T23:59:59.000Z

43

Multiscale approach for modeling hot mix asphalt  

E-Print Network [OSTI]

and is implemented in FE analysis using a user-defined material subroutine (UMAT). A fully implicit algorithm in time-step control is used to enhance the efficiency of the FE analysis. The FE model used in this study simulates experimental data and pavement section....

Dessouky, Samer Hassan

2005-08-29T23:59:59.000Z

44

A Mathematical Analysis of Atomistic-to-Continuum (AtC) Multiscale Coupling Methods  

SciTech Connect (OSTI)

We have worked on several projects aimed at improving the efficiency and understanding of multiscale methods, especially those applicable to problems involving atomistic-to-continuum coupling. Activities include blending methods for AtC coupling and efficient quasi-continuum methods for problems with long-range interactions.

Gunzburger, Max

2013-11-13T23:59:59.000Z

45

Integrated Multiscale Modeling of Molecular Computing Devices  

SciTech Connect (OSTI)

Significant advances were made on all objectives of the research program. We have developed fast multiresolution methods for performing electronic structure calculations with emphasis on constructing efficient representations of functions and operators. We extended our approach to problems of scattering in solids, i.e. constructing fast algorithms for computing above the Fermi energy level. Part of the work was done in collaboration with Robert Harrison and George Fann at ORNL. Specific results (in part supported by this grant) are listed here and are described in greater detail. (1) We have implemented a fast algorithm to apply the Green's function for the free space (oscillatory) Helmholtz kernel. The algorithm maintains its speed and accuracy when the kernel is applied to functions with singularities. (2) We have developed a fast algorithm for applying periodic and quasi-periodic, oscillatory Green's functions and those with boundary conditions on simple domains. Importantly, the algorithm maintains its speed and accuracy when applied to functions with singularities. (3) We have developed a fast algorithm for obtaining and applying multiresolution representations of periodic and quasi-periodic Green's functions and Green's functions with boundary conditions on simple domains. (4) We have implemented modifications to improve the speed of adaptive multiresolution algorithms for applying operators which are represented via a Gaussian expansion. (5) We have constructed new nearly optimal quadratures for the sphere that are invariant under the icosahedral rotation group. (6) We obtained new results on approximation of functions by exponential sums and/or rational functions, one of the key methods that allows us to construct separated representations for Green's functions. (7) We developed a new fast and accurate reduction algorithm for obtaining optimal approximation of functions by exponential sums and/or their rational representations.

Gregory Beylkin

2012-03-23T23:59:59.000Z

46

Multiscale modeling of oscillations and spiral waves in Dictyostelium populations  

E-Print Network [OSTI]

Unicellular organisms exhibit elaborate collective behaviors in response to environmental cues. These behaviors are controlled by complex biochemical networks within individual cells and coordinated through cell-to-cell communication. Describing these behaviors requires new mathematical models that can bridge scales -- from biochemical networks within individual cells to spatially structured cellular populations. Here, we present a family of multiscale models for the emergence of spiral waves in the social amoeba Dictyostelium discoideum. Our models exploit new experimental advances that allow for the direct measurement and manipulation of the small signaling molecule cAMP used by Dictyostelium cells to coordinate behavior in cellular populations. Inspired by recent experiments, we model the Dictyostelium signaling network as an excitable system coupled to various pre-processing modules. We use this family of models to study spatially unstructured populations by constructing phase diagrams that relate the properties of population-level oscillations to parameters in the underlying biochemical network. We then extend our models to include spatial structure and show how they naturally give rise to spiral waves. Our models exhibit a wide range of novel phenomena including a density dependent frequency change, bistability, and dynamic death due to slow cAMP dynamics. Our modeling approach provides a powerful tool for bridging scales in modeling of Dictyostelium populations.

Javad Noorbakhsh; David Schwab; Allyson Sgro; Thomas Gregor; Pankaj Mehta

2014-09-12T23:59:59.000Z

47

Modeling and Simulation of Electromutagenic Processes for Multiscale Modification of Concrete Jinko Kanno1  

E-Print Network [OSTI]

Modeling and Simulation of Electromutagenic Processes for Multiscale Modification of Concrete Jinko Engineering Program, Louisiana Tech University ABSTRACT Concrete contains numerous pores that allow of concrete with solid materials or nanoparticles tends to improve the strength significantly. In this paper

Kanno,Jinko

48

A Multiscale Dynamo Model Driven by Quasi-geostrophic Convection  

E-Print Network [OSTI]

A convection-driven multiscale dynamo model is developed for the plane layer geometry in the limit of low Rossby number. The small-scale fluctuating dynamics are described by a magnetically-modified quasi-geostrophic equation set, and the large-scale mean dynamics are governed by a diagnostic thermal wind balance. The model utilizes three timescales that respectively characterize the convective timescale, the large-scale magnetic diffusion timescale, and the large-scale thermal diffusion timescale. Distinct equations are derived for the cases of order one and low magnetic Prandtl number. It is shown that the low magnetic Prandtl number model is characterized by a magnetic to kinetic energy ratio that is asymptotically large, with ohmic dissipation dominating viscous dissipation on the large-scales. For the order one magnetic Prandtl number model the magnetic and kinetic energies are equipartitioned and both ohmic and viscous dissipation are weak on the large-scales; large-scale ohmic dissipation occurs in thi...

Calkins, Michael A; Tobias, Steven M; Aurnou, Jonathan M

2015-01-01T23:59:59.000Z

49

Common themes, methods, and applications in multiscale science  

SciTech Connect (OSTI)

In 1993, under the leadership of Richard Slansky, the T-Division Director, an initiative was started to facilitate cross communications and interactions between a large number of different workers who were, from their own perspectives and with regard to their own challenges, in fact working on very difficult problems which involved multiple size and time scales. The realization of this common element had the potential for valuable mutual interaction. His initiative led initially to a competency development initiative and subsequently to a broadening recognition of the importance of multiscale science and a broadening application of it to problems and concerns inherent in significant fields of endeavor at the Los Alamos National Laboratory. One of the aspects of this effort was a series of meetings which emphasizes cross communication between the workers. It was realized early on that this cross communication would be fare more effective, considering the difficult technical nature and that the range of the material was well outside the area of specialization of individual members of the group, if notes were taken, written up, and disseminated. This report represents the collection of these notes.

Baker, G.A. Jr.

1997-10-01T23:59:59.000Z

50

Bayesian data assimilation for stochastic multiscale models of transport in porous media.  

SciTech Connect (OSTI)

We investigate Bayesian techniques that can be used to reconstruct field variables from partial observations. In particular, we target fields that exhibit spatial structures with a large spectrum of lengthscales. Contemporary methods typically describe the field on a grid and estimate structures which can be resolved by it. In contrast, we address the reconstruction of grid-resolved structures as well as estimation of statistical summaries of subgrid structures, which are smaller than the grid resolution. We perform this in two different ways (a) via a physical (phenomenological), parameterized subgrid model that summarizes the impact of the unresolved scales at the coarse level and (b) via multiscale finite elements, where specially designed prolongation and restriction operators establish the interscale link between the same problem defined on a coarse and fine mesh. The estimation problem is posed as a Bayesian inverse problem. Dimensionality reduction is performed by projecting the field to be inferred on a suitable orthogonal basis set, viz. the Karhunen-Loeve expansion of a multiGaussian. We first demonstrate our techniques on the reconstruction of a binary medium consisting of a matrix with embedded inclusions, which are too small to be grid-resolved. The reconstruction is performed using an adaptive Markov chain Monte Carlo method. We find that the posterior distributions of the inferred parameters are approximately Gaussian. We exploit this finding to reconstruct a permeability field with long, but narrow embedded fractures (which are too fine to be grid-resolved) using scalable ensemble Kalman filters; this also allows us to address larger grids. Ensemble Kalman filtering is then used to estimate the values of hydraulic conductivity and specific yield in a model of the High Plains Aquifer in Kansas. Strong conditioning of the spatial structure of the parameters and the non-linear aspects of the water table aquifer create difficulty for the ensemble Kalman filter. We conclude with a demonstration of the use of multiscale stochastic finite elements to reconstruct permeability fields. This method, though computationally intensive, is general and can be used for multiscale inference in cases where a subgrid model cannot be constructed.

Marzouk, Youssef M. (Massachusetts Institute of Technology, Cambridge, MA); van Bloemen Waanders, Bart Gustaaf (Sandia National Laboratories, Albuquerque NM); Parno, Matthew (Massachusetts Institute of Technology, Cambridge, MA); Ray, Jaideep; Lefantzi, Sophia; Salazar, Luke (Sandia National Laboratories, Albuquerque NM); McKenna, Sean Andrew (Sandia National Laboratories, Albuquerque NM); Klise, Katherine A. (Sandia National Laboratories, Albuquerque NM)

2011-10-01T23:59:59.000Z

51

Collaborating for Multi-Scale Chemical Science  

SciTech Connect (OSTI)

Advanced model reduction methods were developed and integrated into the CMCS multiscale chemical science simulation software. The new technologies were used to simulate HCCI engines and burner flames with exceptional fidelity.

William H. Green

2006-07-14T23:59:59.000Z

52

Global and multi-scale features of solar wind-magnetosphere coupling: From modeling to forecasting  

E-Print Network [OSTI]

and substorms; 2784 Magnetospheric Physics: Solar wind/magnetosphere interactions; 3210 Mathematical Geophysics in the solar wind-magnetosphere interaction, de- veloping first principles models that encompass allGlobal and multi-scale features of solar wind-magnetosphere coupling: From modeling to forecasting

Sitnov, Mikhail I.

53

A second gradient theoretical framework for hierarchical multiscale modeling of materials  

SciTech Connect (OSTI)

A theoretical framework for the hierarchical multiscale modeling of inelastic response of heterogeneous materials has been presented. Within this multiscale framework, the second gradient is used as a non local kinematic link between the response of a material point at the coarse scale and the response of a neighborhood of material points at the fine scale. Kinematic consistency between these scales results in specific requirements for constraints on the fluctuation field. The wryness tensor serves as a second-order measure of strain. The nature of the second-order strain induces anti-symmetry in the first order stress at the coarse scale. The multiscale ISV constitutive theory is couched in the coarse scale intermediate configuration, from which an important new concept in scale transitions emerges, namely scale invariance of dissipation. Finally, a strategy for developing meaningful kinematic ISVs and the proper free energy functions and evolution kinetics is presented.

Luscher, Darby J [Los Alamos National Laboratory; Bronkhorst, Curt A [Los Alamos National Laboratory; Mc Dowell, David L [GEORGIA TECH

2009-01-01T23:59:59.000Z

54

Multiscale Modeling of TiO2 Nanoparticle Production in Flame Reactors: Effect of Chemical Mechanism  

E-Print Network [OSTI]

Multiscale Modeling of TiO2 Nanoparticle Production in Flame Reactors: Effect of Chemical Mechanism and Engineering Mechanics, The UniVersity of Texas, Austin, Texas 78712 For titanium dioxide (TiO2) nanoparticles, catalysis, energy, and semiconductors. Titanium dioxide (TiO2) nanoparticles are traditionally used

Raman, Venkat

55

SMART: A Stochastic Multiscale Model for the Analysis of Energy Resources, Technology and Policy  

E-Print Network [OSTI]

, the United States needs to transition to an energy system with much lower carbon emissions and reduced), and the balance of energy carriers such as electricity, hydrogen, alcohol and synthetic fuels, and endSMART: A Stochastic Multiscale Model for the Analysis of Energy Resources, Technology and Policy

Powell, Warren B.

56

SMART: A Stochastic Multiscale Model for the Analysis of Energy Resources, Technology and Policy  

E-Print Network [OSTI]

. Introduction Over the next few decades, the United States needs to transition to an energy system with much, renewable, sequestered fossil), and the balance of energy carriers including electricity, hydrogen, alcoholSMART: A Stochastic Multiscale Model for the Analysis of Energy Resources, Technology and Policy

Powell, Warren B.

57

Multiscale Strategic Planning Model for the Design of Integrated Ethanol and Gasoline Supply Chain  

E-Print Network [OSTI]

1 Multiscale Strategic Planning Model for the Design of Integrated Ethanol and Gasoline Supply address the design and planning of an integrated ethanol and gasoline supply chain. We assume, distribution centers where blending takes place, and the retail gas stations where different blends of gasoline

Grossmann, Ignacio E.

58

Coupled numerical approach combining finite volume and lattice Boltzmann methods for multi-scale multi-physicochemical processes  

SciTech Connect (OSTI)

A coupled (hybrid) simulation strategy spatially combining the finite volume method (FVM) and the lattice Boltzmann method (LBM), called CFVLBM, is developed to simulate coupled multi-scale multi-physicochemical processes. In the CFVLBM, computational domain of multi-scale problems is divided into two sub-domains, i.e., an open, free fluid region and a region filled with porous materials. The FVM and LBM are used for these two regions, respectively, with information exchanged at the interface between the two sub-domains. A general reconstruction operator (RO) is proposed to derive the distribution functions in the LBM from the corresponding macro scalar, the governing equation of which obeys the convection–diffusion equation. The CFVLBM and the RO are validated in several typical physicochemical problems and then are applied to simulate complex multi-scale coupled fluid flow, heat transfer, mass transport, and chemical reaction in a wall-coated micro reactor. The maximum ratio of the grid size between the FVM and LBM regions is explored and discussed. -- Highlights: •A coupled simulation strategy for simulating multi-scale phenomena is developed. •Finite volume method and lattice Boltzmann method are coupled. •A reconstruction operator is derived to transfer information at the sub-domains interface. •Coupled multi-scale multiple physicochemical processes in micro reactor are simulated. •Techniques to save computational resources and improve the efficiency are discussed.

Chen, Li; He, Ya-Ling [Key Laboratory of Thermo-Fluid Science and Engineering of MOE, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)] [Key Laboratory of Thermo-Fluid Science and Engineering of MOE, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China); Kang, Qinjun [Computational Earth Science Group (EES-16), Los Alamos National Laboratory, Los Alamos, NM (United States)] [Computational Earth Science Group (EES-16), Los Alamos National Laboratory, Los Alamos, NM (United States); Tao, Wen-Quan, E-mail: wqtao@mail.xjtu.edu.cn [Key Laboratory of Thermo-Fluid Science and Engineering of MOE, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)] [Key Laboratory of Thermo-Fluid Science and Engineering of MOE, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)

2013-12-15T23:59:59.000Z

59

Multi-Scale Multi-physics Methods Development for the Calculation of Hot-Spots in the NGNP  

SciTech Connect (OSTI)

Radioactive gaseous fission products are released out of the fuel element at a significantly higher rate when the fuel temperature exceeds 1600°C in high-temperature gas-cooled reactors (HTGRs). Therefore, it is of paramount importance to accurately predict the peak fuel temperature during all operational and design-basis accident conditions. The current methods used to predict the peak fuel temperature in HTGRs, such as the Next-Generation Nuclear Plant (NGNP), estimate the average fuel temperature in a computational mesh modeling hundreds of fuel pebbles or a fuel assembly in a pebble-bed reactor (PBR) or prismatic block type reactor (PMR), respectively. Experiments conducted in operating HTGRs indicate considerable uncertainty in the current methods and correlations used to predict actual temperatures. The objective of this project is to improve the accuracy in the prediction of local "hot" spots by developing multi-scale, multi- physics methods and implementing them within the framework of established codes used for NGNP analysis. The multi-scale approach which this project will implement begins with defining suitable scales for a physical and mathematical model and then deriving and applying the appropriate boundary conditions between scales. The macro scale is the greatest length that describes the entire reactor, whereas the meso scale models only a fuel block in a prismatic reactor and ten to hundreds of pebbles in a pebble bed reactor. The smallest scale is the micro scale--the level of a fuel kernel of the pebble in a PBR and fuel compact in a PMR--which needs to be resolved in order to calculate the peak temperature in a fuel kernel.

Downar, Thomas; Seker, Volkan

2013-04-30T23:59:59.000Z

60

Multiscale modeling of solar cells with interface phenomena  

E-Print Network [OSTI]

We describe a mathematical model for heterojunctions in semiconductors which can be used, e.g., for modeling higher efficiency solar cells. The continuum model involves well-known drift-diffusion equations posed away from the interface. These are coupled with interface conditions with a nonhomogeneous jump for the potential, and Robin-like interface conditions for carrier transport. The interface conditions arise from approximating the interface region by a lower-dimensional manifold. The data for the interface conditions are calculated by a Density Functional Theory (DFT) model over a few atomic layers comprising the interface region. We propose a domain decomposition method (DDM) approach to decouple the continuum model on subdomains which is implemented in every step of the Gummel iteration. We show results for CIGS/CdS, Si/ZnS, and Si/GaAs heterojunctions.

Foster, David H; Peszynska, Malgorzata; Schneider, Guenter

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

Continuum Level Formulation and Implementation of a Multi-scale Model for Vanadium  

SciTech Connect (OSTI)

A multi-scale approach is used to construct a continuum strength model for vanadium. The model is formulated assuming plastic deformation by dislocation motion and strain hardening due to dislocation interactions. Dislocation density is adopted as the state variable in the model. Information from molecular statics, molecular dynamics and dislocation dynamics simulations is combined to create kinetic relations for dislocation motion, strain hardening relations and evolution equations for the dislocation density. Implicit time integration of the constitutive equations is described in the context of implementation in a finite element code. Results are provided illustrating the strain, strain rate, temperature and pressure dependence of the constitutive model.

Lawrence Livermore National Laboratory

2009-08-17T23:59:59.000Z

62

Evaluation of Hydrometeor Occurrence Profiles in the Multiscale Modeling Framework Climate Model using Atmospheric Classification  

SciTech Connect (OSTI)

Vertical profiles of hydrometeor occurrence from the Multiscale Modeling Framework (MMF) climate model are compared with profiles observed by a vertically pointing millimeter wavelength cloud-radar (located in the U.S. Southern Great Plains) as a function of the largescale atmospheric state. The atmospheric state is determined by classifying (or clustering) the large-scale (synoptic) fields produced by the MMF and a numerical weather prediction model using a neural network approach. The comparison shows that for cold frontal and post-cold frontal conditions the MMF produces profiles of hydrometeor occurrence that compare favorably with radar observations, while for warm frontal conditions the model tends to produce hydrometeor fractions that are too large with too much cloud (non-precipitating hydrometeors) above 7 km and too much precipitating hydrometeor coverage below 7 km. We also find that the MMF has difficulty capturing the formation of low clouds and that for all atmospheric states that occur during June, July, and August, the MMF produces too much high and thin cloud, especially above 10 km.

Marchand, Roger T.; Beagley, Nathaniel; Ackerman, Thomas P.

2009-09-01T23:59:59.000Z

63

Sustainable Manufacturing via Multi-Scale, Physics-Based Process...  

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

Manufacturing via Multi-Scale, Physics-Based Process Modeling and Manufacturing-Informed Design, April 2013 Sustainable Manufacturing via Multi-Scale, Physics-Based Process...

64

Negative magnetic eddy diffusivities from test-field method and multiscale stability theory  

E-Print Network [OSTI]

The generation of large-scale magnetic field in the kinematic regime in the absence of an alpha-effect is investigated by following two different approaches, namely the test-field method and multiscale stability theory relying on the homogenisation technique. We show analytically that the former, applied for the evaluation of magnetic eddy diffusivities, yields results that fully agree with the latter. Our computations of the magnetic eddy diffusivity tensor for the specific instances of the parity-invariant flow-IV of G.O. Roberts and the modified Taylor-Green flow in a suitable range of parameter values confirm the findings of previous studies, and also explain some of their apparent contradictions. The two flows have large symmetry groups; this is used to considerably simplify the eddy diffusivity tensor. Finally, a new analytic result is presented: upon expressing the eddy diffusivity tensor in terms of solutions to auxiliary problems for the adjoint operator, we derive relations between magnetic eddy dif...

Andrievsky, Alexander; Noullez, Alain; Zheligovsky, Vladislav

2015-01-01T23:59:59.000Z

65

Negative magnetic eddy diffusivities from test-field method and multiscale stability theory  

E-Print Network [OSTI]

The generation of large-scale magnetic field in the kinematic regime in the absence of an alpha-effect is investigated by following two different approaches, namely the test-field method and multiscale stability theory relying on the homogenisation technique. We show analytically that the former, applied for the evaluation of magnetic eddy diffusivities, yields results that fully agree with the latter. Our computations of the magnetic eddy diffusivity tensor for the specific instances of the parity-invariant flow-IV of G.O. Roberts and the modified Taylor-Green flow in a suitable range of parameter values confirm the findings of previous studies, and also explain some of their apparent contradictions. The two flows have large symmetry groups; this is used to considerably simplify the eddy diffusivity tensor. Finally, a new analytic result is presented: upon expressing the eddy diffusivity tensor in terms of solutions to auxiliary problems for the adjoint operator, we derive relations between magnetic eddy diffusivity tensors that arise for opposite small-scale flows v(x) and -v(x).

Alexander Andrievsky; Axel Brandenburg; Alain Noullez; Vladislav Zheligovsky

2015-01-19T23:59:59.000Z

66

Eye Localization through Multiscale Sparse Dictionaries Fei Yang, Junzhou Huang, Peng Yang and Dimitris Metaxas  

E-Print Network [OSTI]

Eye Localization through Multiscale Sparse Dictionaries Fei Yang, Junzhou Huang, Peng Yang and Dimitris Metaxas Abstract-- This paper presents a new eye localization method via Multiscale Sparse Dictionaries (MSD). We built a pyramid of dictionaries that models context information at multiple scales. Eye

Huang, Junzhou

67

Assessing the Effects of Anthropogenic Aerosols on Pacific Storm Track Using a Multiscale Global Climate Model  

SciTech Connect (OSTI)

Atmospheric aerosols impact weather and global general circulation by modifying cloud and precipitation processes, but the magnitude of cloud adjustment by aerosols remains poorly quantified and represents the largest uncertainty in estimated forcing of climate change. Here we assess the impacts of anthropogenic aerosols on the Pacific storm track using a multi-scale global aerosol-climate model (GCM). Simulations of two aerosol scenarios corresponding to the present day and pre-industrial conditions reveal long-range transport of anthropogenic aerosols across the north Pacific and large resulting changes in the aerosol optical depth, cloud droplet number concentration, and cloud and ice water paths. Shortwave and longwave cloud radiative forcing at the top of atmosphere are changed by - 2.5 and + 1.3 W m-2, respectively, by emission changes from pre-industrial to present day, and an increased cloud-top height indicates invigorated mid-latitude cyclones. The overall increased precipitation and poleward heat transport reflect intensification of the Pacific storm track by anthropogenic aerosols. Hence, this work provides for the first time a global perspective of the impacts of Asian pollution outflows from GCMs. Furthermore, our results suggest that the multi-scale modeling framework is essential in producing the aerosol invigoration effect of deep convective clouds on the global scale.

Wang, Yuan; Wang, Minghuai; Zhang, Renyi; Ghan, Steven J.; Lin, Yun; Hu, Jiaxi; Pan, Bowen; Levy, Misti; Jiang, Jonathan; Molina, Mario J.

2014-05-13T23:59:59.000Z

68

Multiscale Modeling and Simulation of Organic Solar Cells  

E-Print Network [OSTI]

In this article, we continue our mathematical study of organic solar cells (OSCs) and propose a two-scale (micro- and macro-scale) model of heterojunction OSCs with interface geometries characterized by an arbitrarily complex morphology. The microscale model consists of a system of partial and ordinary differential equations in an heterogeneous domain, that provides a full description of excitation/transport phenomena occurring in the bulk regions and dissociation/recombination processes occurring in a thin material slab across the interface. The macroscale model is obtained by a micro-to-macro scale transition that consists of averaging the mass balance equations in the normal direction across the interface thickness, giving rise to nonlinear transmission conditions that are parametrized by the interfacial width. These conditions account in a lumped manner for the volumetric dissociation/recombination phenomena occurring in the thin slab and depend locally on the electric field magnitude and orientation. Usi...

de Falco, Carlo; Sacco, Riccardo; Verri, Maurizio

2012-01-01T23:59:59.000Z

69

Multiscale Modeling and Simulation of Fluid Flows in Inelastic Media  

E-Print Network [OSTI]

in porous media (e.g. soil), Elasticity equations in heterogeneous media (concrete, asphalt), etc porous media s The Fluid-Structure interaction (FSI) problem at the microscale and numerical methods with computational solutions s Numerical upscaling of flow in deformable porous media #12;- p. 3/42 Why homogenize

Popov, Peter

70

Multi-scale quantum point contact model for filamentary conduction in resistive random access memories devices  

SciTech Connect (OSTI)

We depart from first-principle simulations of electron transport along paths of oxygen vacancies in HfO{sub 2} to reformulate the Quantum Point Contact (QPC) model in terms of a bundle of such vacancy paths. By doing this, the number of model parameters is reduced and a much clearer link between the microscopic structure of the conductive filament (CF) and its electrical properties can be provided. The new multi-scale QPC model is applied to two different HfO{sub 2}-based devices operated in the unipolar and bipolar resistive switching (RS) modes. Extraction of the QPC model parameters from a statistically significant number of CFs allows revealing significant structural differences in the CF of these two types of devices and RS modes.

Lian, Xiaojuan, E-mail: xjlian2005@gmail.com; Cartoixà, Xavier; Miranda, Enrique; Suñé, Jordi [Departament d'Enginyeria Electrònica, Universitat Autònoma de Barcelona, 08193 Bellaterra (Spain); Perniola, Luca [CEA-LETI, MINATEC, Grenoble (France); Rurali, Riccardo [Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus de Bellaterra, 08193 Bellaterra (Spain); Long, Shibing; Liu, Ming [Laboratory of Nanofabrication and Novel Device Integration, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029 (China)

2014-06-28T23:59:59.000Z

71

Multiscale Thermohydrologic Model Supporting the Licence Application for the Yucca Mountain Repository  

SciTech Connect (OSTI)

The MultiScale ThermoHydrologic Model (MSTHM) predicts thermal-hydrologic (TH) conditions within emplacement tunnels (drifts) and in the adjoining host rock at Yucca Mountain, Nevada, which is the proposed site for a radioactive waste repository in the US. Because these predictions are used in the performance assessment of the Yucca Mountain repository, they must address the influence of variability and uncertainty of the engineered- and natural-system parameters that significantly influence those predictions. Parameter-sensitivity studies show that the MSTHM predictions adequately propagate the influence of parametric variability and uncertainty. Model-validation studies show that the influence of conceptual-model uncertainty on the MSTHM predictions is insignificant compared to that of parametric uncertainty, which is propagated through the MSTHM.

T.A> Buscheck; Y. Sun; Y. Hao

2006-03-28T23:59:59.000Z

72

Implementation and Application of SAPRC07 and MCM Mechanisms in the Multi-scale Community Air Quality Model  

E-Print Network [OSTI]

mechanism. In this study, two state-of-the-science photochemical mechanisms, SAPRC07 and Master Chemical Mechanism (MCM) v3.1, were implemented in the Community Multi-scale Air Quality Model (CMAQ) version 4.6 developed by the US EPA to study a high ozone (O...

Li, Jingyi

2012-02-14T23:59:59.000Z

73

Multiscale modeling of ice deformation behavior M. Montagnata,, O. Castelnaub, P. D. Bonsc, S. H. Fariad,e, O.  

E-Print Network [OSTI]

Multiscale modeling of ice deformation behavior M. Montagnata,, O. Castelnaub, P. D. Bonsc, S. H France (IUF), Paris, France Abstract Understanding the flow of ice in glaciers and polar ice sheets is of increasing relevance in a time of potentially significant climate change. The flow of ice has hitherto

Boyer, Edmond

74

Overview of Computer-Aided Engineering of Batteries and Introduction to Multi-Scale, Multi-Dimensional Modeling of Li-Ion Batteries (Presentation)  

SciTech Connect (OSTI)

This 2012 Annual Merit Review presentation gives an overview of the Computer-Aided Engineering of Batteries (CAEBAT) project and introduces the Multi-Scale, Multi-Dimensional model for modeling lithium-ion batteries for electric vehicles.

Pesaran, A.; Kim, G. H.; Smith, K.; Santhanagopalan, S.; Lee, K. J.

2012-05-01T23:59:59.000Z

75

Multiscale time-integration for particle-in-cell methods. P. Cazeauxa  

E-Print Network [OSTI]

. The direct comparisons to resolved PIC simulations show good agreement. We show that the speedup) to efforts in developing nuclear fusion reactors (tokamaks) to everyday human environment (lighting, industrial processes). Plasma phenomena are typ- ically characterized by a complex multiscale character

Thévenaz, Jacques

76

Validation and Calibration of Nuclear Thermal Hydraulics Multiscale Multiphysics Models - Subcooled Flow Boiling Study  

SciTech Connect (OSTI)

In addition to validation data plan, development of advanced techniques for calibration and validation of complex multiscale, multiphysics nuclear reactor simulation codes are a main objective of the CASL VUQ plan. Advanced modeling of LWR systems normally involves a range of physico-chemical models describing multiple interacting phenomena, such as thermal hydraulics, reactor physics, coolant chemistry, etc., which occur over a wide range of spatial and temporal scales. To a large extent, the accuracy of (and uncertainty in) overall model predictions is determined by the correctness of various sub-models, which are not conservation-laws based, but empirically derived from measurement data. Such sub-models normally require extensive calibration before the models can be applied to analysis of real reactor problems. This work demonstrates a case study of calibration of a common model of subcooled flow boiling, which is an important multiscale, multiphysics phenomenon in LWR thermal hydraulics. The calibration process is based on a new strategy of model-data integration, in which, all sub-models are simultaneously analyzed and calibrated using multiple sets of data of different types. Specifically, both data on large-scale distributions of void fraction and fluid temperature and data on small-scale physics of wall evaporation were simultaneously used in this work’s calibration. In a departure from traditional (or common-sense) practice of tuning/calibrating complex models, a modern calibration technique based on statistical modeling and Bayesian inference was employed, which allowed simultaneous calibration of multiple sub-models (and related parameters) using different datasets. Quality of data (relevancy, scalability, and uncertainty) could be taken into consideration in the calibration process. This work presents a step forward in the development and realization of the “CIPS Validation Data Plan” at the Consortium for Advanced Simulation of LWRs to enable quantitative assessment of the CASL modeling of Crud-Induced Power Shift (CIPS) phenomenon, in particular, and the CASL advanced predictive capabilities, in general. This report is prepared for the Department of Energy’s Consortium for Advanced Simulation of LWRs program’s VUQ Focus Area.

Anh Bui; Nam Dinh; Brian Williams

2013-09-01T23:59:59.000Z

77

Multiscale Modeling of Grain Boundary Segregation and Embrittlement in Tungsten for Mechanistic Design of Alloys for Coal Fired Plants  

SciTech Connect (OSTI)

Based on a recent discovery of premelting-like grain boundary segregation in refractory metals occurring at high temperatures and/or high alloying levels, this project investigated grain boundary segregation and embrittlement in tungsten (W) based alloys. Specifically, new interfacial thermodynamic models have been developed and quantified to predict high-temperature grain boundary segregation in the W-Ni binary alloy and W-Ni-Fe, W-Ni-Ti, W-Ni-Co, W-Ni-Cr, W-Ni-Zr and W-Ni-Nb ternary alloys. The thermodynamic modeling results have been experimentally validated for selected systems. Furthermore, multiscale modeling has been conducted at continuum, atomistic and quantum-mechanical levels to link grain boundary segregation with embrittlement. In summary, this 3-year project has successfully developed a theoretical framework in combination with a multiscale modeling strategy for predicting grain boundary segregation and embrittlement in W based alloys.

Luo, Jian; Tomar, Vikas; Zhou, Naixie; Lee, Hongsuk

2013-06-30T23:59:59.000Z

78

Multiscale Simulation and Uncertainty Quantification Techniques for Richards' Equation in Heterogeneous Media  

E-Print Network [OSTI]

In this dissertation, we develop multiscale finite element methods and uncertainty quantification technique for Richards' equation, a mathematical model to describe fluid flow in unsaturated porous media. Both coarse-level and fine-level numerical...

Kang, Seul Ki

2012-10-19T23:59:59.000Z

79

Evaluation of the Multi-scale Modeling Framework Using Data from the Atmospheric Radiation Measurement Program  

SciTech Connect (OSTI)

One of the goals of the Atmospheric Radiation Measurement (ARM) program is to provide long-term observations for evaluating and improving cloud and radiation treatment in global climate models. Unfortunately, the traditional parametric approach of diagnosing cloud and radiation properties for gridcells that are tens to hundreds kilometers across from large-scale model fields is not well suited for comparison with time series of ground based observations at selected locations. A recently emerging approach called a multi-scale modeling framework (MMF) has shown promise to bridge the scale gap. The MMF consists of a two-dimensional or small three-dimensional cloud resolving model (CRM) embedded into each grid column of the Community Atmospheric Model (CAM), thereby computing cloud properties at a scale that is more consistent with observations. We present a comparison of data from two ARM sites, one at the Southern Great Plains (SGP) in Oklahoma and one at Nauru Island in the Tropical Western Pacific (TWP) region, with output from both the CAM and MMF. Two sets of one year long simulations are considered: one using climatological sea surface temperatures (SST) and another using 1999 SST. Each set includes a run with the MMF as well as the CAM run with traditional or standard cloud and radiation treatment. Time series of cloud fraction, precipitation intensity, and downwelling solar radiation flux at the surface are statistically analyzed. For the TWP site, nearly all parameters of frequency distributions of these variables from the MMF run are shown to be more consistent with observation than those from the CAM run. This change is attributed to the improved representation of convective clouds in the MMF compared to the conventional climate model. For the SGP, the MMF shows little to no improvement in predicting the same quantities. Possible causes of this lack of improvement are discussed.

Ovtchinnikov, Mikhail; Ackerman, Thomas P.; Marchand, Roger T.; Khairoutdinov, Marat

2006-05-01T23:59:59.000Z

80

Toward Multi-scale Modeling and simulation of conduction in heterogeneous materials.  

SciTech Connect (OSTI)

This report summarizes a project in which the authors sought to develop and deploy: (i) experimental techniques to elucidate the complex, multiscale nature of thermal transport in particle-based materials; and (ii) modeling approaches to address current challenges in predicting performace variability of materials (e.g., identifying and characterizing physical- chemical processes and their couplings across multiple length and time scales, modeling infor- mation transfer between scales, and statically and dynamically resolving material structure and its evolution during manufacturing and device performance). Experimentally, several capabilities were sucessfully advanced. As discussed in Chapter 2 a flash diffusivity capabil- ity for measuring homogeneous thermal conductivity of pyrotechnic powders (and beyond) was advanced; leading to enhanced characterization of pyrotechnic materials and properties impacting component development. Chapter 4 describes sucess for the first time, although preliminary, in resolving thermal fields at speeds and spatial scales relevant to energetic components. Chapter 7 summarizes the first ever (as far as the authors know) application of TDTR to actual pyrotechnic materials. This is the first attempt to actually characterize these materials at the interfacial scale. On the modeling side, new capabilities in image processing of experimental microstructures and direct numerical simulation on complicated structures were advanced (see Chapters 3 and 5). In addition, modeling work described in Chapter 8 led to improved prediction of interface thermal conductance from first principles calculations. Toward the second point, for a model system of packed particles, significant headway was made in implementing numerical algorithms and collecting data to justify the approach in terms of highlighting the phenomena at play and pointing the way forward in de- veloping and informing the kind of modeling approach oringinally envisioned (see Chapter 6). In both cases much more remains to be accomplished.

Lechman, Jeremy B.; Battaile, Corbett Chandler.; Bolintineanu, Dan; Cooper, Marcia A.; Erikson, William W.; Foiles, Stephen M.; Kay, Jeffrey J [Sandia National Laboratories, Livermore, CA; Phinney, Leslie M.; Piekos, Edward S.; Specht, Paul Elliott; Wixom, Ryan R.; Yarrington, Cole

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

Evaluation of the Multi-Scale Modeling Framework using Data from the Atmospheric Radiation Measurement Program  

SciTech Connect (OSTI)

One of the goals of the Atmospheric Radiation Measurement (ARM) program was to provide long-term observations for evaluation of cloud and radiation treatment in global climate models. Unfortunately, traditional parametric approach of diagnosing cloud and radiation properties from large-scale model fields is not well suited for comparison with observed time series at selected locations. A recently emerging approach called the multi-scale modeling framework (MMF) has shown promise to bridge the gap. MMF consists of a two-dimensional cloud system resolving model (CSRM) embedded into each CAM grid column of the Community Atmospheric Model (CAM), thereby computing cloud properties at a scale that is more consistent with observations. Because the approach is computationally expensive only limited simulations have been carried out. In this presentation, we will present a comparison of data from two ARM sites, one at the Southern Great Plains (SGP) in Oklahoma and one at Nauru island in the Tropical Western Pacific (TWP) region, with output from both CAM and MMF. Two sets of one year long simulations are considered: one using climatological sea surface temperatures (SST) and another using 1999 SST. Each set includes a run with MMF as well as CAM run with traditional or standard cloud and radiation treatment. Time series of cloud fraction, precipitation intensity, and downwelling solar radiation flux at the surface are statistically analyzed. For the TWP site, nearly all parameters of frequency distributions of these variables from MMF run are shown to be more consistent with observation than those from CAM run. For the SGP, the improvements are marginal.

Ovchinnikov, Mikhail; Ackerman, Thomas P.; Marchand, Roger T.; Khairoutdinov, Marat

2004-07-01T23:59:59.000Z

82

A Unified Multi-Scale Model for Pore-Scale Flow Simulations in Soils  

SciTech Connect (OSTI)

Pore-scale simulations have received increasing interest in subsurface sciences to provide mechanistic insights into the macroscopic phenomena of water flow and reactive transport processes. The application of the pore scale simulations to soils and sediments is, however, challenged because of the characterization limitation that often only allows partial resolution of pore structure and geometry. A significant proportion of the pore space in soils and sediments is below the spatial resolution, forming a mixed media of pore and porous domains. Here we reported a unified multi-scale model (UMSM) that can be used to simulate water flow and transport in mixed media of pore and porous domains under both saturated and unsaturated conditions. The approach modifies the classic Navier-Stokes equation by adding a Darcy term to describe fluid momentum and uses a generalized mass balance equation for saturated and unsaturated conditions. By properly defining physical parameters, the UMSM can be applied in both pore and porous domains. This paper describes the set of equations for the UMSM, a series of validation cases under saturated or unsaturated conditions, and a real soil case for the application of the approach.

Yang, Xiaofan; Liu, Chongxuan; Shang, Jianying; Fang, Yilin; Bailey, Vanessa L.

2014-01-30T23:59:59.000Z

83

MULTI-SCALE MODELING AND APPROXIMATION ASSISTED OPTIMIZATION OF BARE TUBE HEAT EXCHANGERS  

SciTech Connect (OSTI)

Air-to-refrigerant heat exchangers are very common in air-conditioning, heat pump and refrigeration applications. In these heat exchangers, there is a great benefit in terms of size, weight, refrigerant charge and heat transfer coefficient, by moving from conventional channel sizes (~ 9mm) to smaller channel sizes (< 5mm). This work investigates new designs for air-to-refrigerant heat exchangers with tube outer diameter ranging from 0.5 to 2.0mm. The goal of this research is to develop and optimize the design of these heat exchangers and compare their performance with existing state of the art designs. The air-side performance of various tube bundle configurations are analyzed using a Parallel Parameterized CFD (PPCFD) technique. PPCFD allows for fast-parametric CFD analyses of various geometries with topology change. Approximation techniques drastically reduce the number of CFD evaluations required during optimization. Maximum Entropy Design method is used for sampling and Kriging method is used for metamodeling. Metamodels are developed for the air-side heat transfer coefficients and pressure drop as a function of tube-bundle dimensions and air velocity. The metamodels are then integrated with an air-to-refrigerant heat exchanger design code. This integration allows a multi-scale analysis of air-side performance heat exchangers including air-to-refrigerant heat transfer and phase change. Overall optimization is carried out using a multi-objective genetic algorithm. The optimal designs found can exhibit 50 percent size reduction, 75 percent decrease in air side pressure drop and doubled air heat transfer coefficients compared to a high performance compact micro channel heat exchanger with same capacity and flow rates.

Bacellar, Daniel [University of Maryland, College Park; Ling, Jiazhen [University of Maryland, College Park; Aute, Vikrant [University of Maryland, College Park; Radermacher, Reinhard [University of Maryland, College Park; Abdelaziz, Omar [ORNL

2014-01-01T23:59:59.000Z

84

Final Progress Report: FRACTURE AND SUBCRITICAL DEBONDING IN THIN LAYERED STRUCTURES: EXPERIMENTS AND MULTI-SCALE MODELING  

SciTech Connect (OSTI)

Final technical report detailing unique experimental and multi-scale computational modeling capabilities developed to study fracture and subcritical cracking in thin-film structures. Our program to date at Stanford has studied the mechanisms of fracture and fatigue crack-growth in structural ceramics at high temperature, bulk and thin-film glasses in selected moist environments where we demonstrated the presence of a true mechanical fatigue effect in some glass compositions. We also reported on the effects of complex environments and fatigue loading on subcritical cracking that effects the reliability of MEMS and other micro-devices using novel micro-machined silicon specimens and nanomaterial layers.

Reinhold H. Dauskardt

2005-08-30T23:59:59.000Z

85

Modeling of damage in unidirectional ceramic matrix composites and multi-scale experimental validation on third generation SiC/SiC minicomposites  

E-Print Network [OSTI]

1 Modeling of damage in unidirectional ceramic matrix composites and multi-scale experimental to macroscopic tensile tests, the evolution of microscopic damage mechanisms - in the form of matrix cracks and computed tomography tensile tests. A complete model, including both matrix cracking and fiber breaking

Paris-Sud XI, Université de

86

Multiscale numerical methods for partial differential equations using limited global information and their applications  

E-Print Network [OSTI]

. These methods employ limited single or multiple global information. We apply these numerical methods to partial differential equations (elliptic, parabolic and wave equations) with continuum scales. To compute the solution of partial differential equations on a...

Jiang, Lijian

2009-05-15T23:59:59.000Z

87

Electric field based fabrication methods for multi-scale structured surfaces  

E-Print Network [OSTI]

Control of micro/nano scale surface structures and properties is crucial to developing novel functional materials. From an engineering point of view, the development of scalable and economical micro/nano-fabrication methods ...

Joung, Young Soo

2014-01-01T23:59:59.000Z

88

The North American Carbon Program Multi-scale synthesis and Terrestrial Model Intercomparison Project Part 1: Overview and experimental design  

SciTech Connect (OSTI)

Terrestrial biosphere models (TBMs) have become an integral tool for extrapolating local observations and understanding of land-atmosphere carbon exchange to larger regions. The North American Carbon Program (NACP) Multi-scale synthesis and Terrestrial Model Intercomparison Project (MsTMIP) is a formal model intercomparison and evaluation effort focused on improving the diagnosis and attribution of carbon exchange at regional and global scales. MsTMIP builds upon current and past synthesis activities, and has a unique framework designed to isolate, interpret, and inform understanding of how model structural differences impact estimates of carbon uptake and release. Here we provide an overview of the MsTMIP effort and describe how the MsTMIP experimental design enables the assessment and quantification of TBM structural uncertainty. Model structure refers to the types of processes considered (e.g. nutrient cycling, disturbance, lateral transport of carbon), and how these processes are represented (e.g. photosynthetic formulation, temperature sensitivity, respiration) in the models. By prescribing a common experimental protocol with standard spin-up procedures and driver data sets, we isolate any biases and variability in TBM estimates of regional and global carbon budgets resulting from differences in the models themselves (i.e. model structure) and model-specific parameter values. An initial intercomparison of model structural differences is represented using hierarchical cluster diagrams (a.k.a. dendrograms), which highlight similarities and differences in how models account for carbon cycle, vegetation, energy, and nitrogen cycle dynamics. We show that, despite the standardized protocol used to derive initial conditions, models show a high degree of variation for GPP, total living biomass, and total soil carbon, underscoring the influence of differences in model structure and parameterization on model estimates.

Huntzinger, D.N. [Northern Arizona University] [Northern Arizona University; Schwalm, C. [Northern Arizona University] [Northern Arizona University; Michalak, A.M [Carnegie Institution for Science, Stanford] [Carnegie Institution for Science, Stanford; Schaefer, K. [National Snow and Ice Data Center] [National Snow and Ice Data Center; King, A.W. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Wei, Y. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Jacobson, A. [National Snow and Ice Data Center] [National Snow and Ice Data Center; Liu, S. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Cook, R. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Post, W.M. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Berthier, G. [Laboratoire des Sciences du Climat et de l'Environnement (LSCE)] [Laboratoire des Sciences du Climat et de l'Environnement (LSCE); Hayes, D. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Huang, M. [Pacific Northwest National Laboratory (PNNL)] [Pacific Northwest National Laboratory (PNNL); Ito, A. [National Institute for Environmental Studies, Tsukuba, Japan] [National Institute for Environmental Studies, Tsukuba, Japan; Lei, H. [Pacific Northwest National Laboratory (PNNL)] [Pacific Northwest National Laboratory (PNNL); Lu, C. [International Center for Climate and Global Change Research and School of Forestry and Wildlife Sci.] [International Center for Climate and Global Change Research and School of Forestry and Wildlife Sci.; Mao, J. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Peng, C.H. [University of Quebec at Montreal, Institute of Environment Sciences] [University of Quebec at Montreal, Institute of Environment Sciences; Peng, S. [Laboratoire des Sciences du Climat et de l'Environnement (LSCE)] [Laboratoire des Sciences du Climat et de l'Environnement (LSCE); Poulter, B. [Laboratoire des Sciences du Climat et de l'Environnement (LSCE)] [Laboratoire des Sciences du Climat et de l'Environnement (LSCE); Riccuito, D. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Shi, X. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Tian, H. [International Center for Climate and Global Change Research and School of Forestry and Wildlife Sci.] [International Center for Climate and Global Change Research and School of Forestry and Wildlife Sci.; Wang, W. [National Aeronautics and Space Administration (NASA), Ames Research Center, Moffett Field] [National Aeronautics and Space Administration (NASA), Ames Research Center, Moffett Field; Zeng, N. [University of Maryland] [University of Maryland; Zhao, F. [University of Maryland] [University of Maryland; Zhu, Q. [Laboratory for Ecological Forecasting and Northwest Agriculture and Forestry University] [Laboratory for Ecological Forecasting and Northwest Agriculture and Forestry University

2013-01-01T23:59:59.000Z

89

Local Estimation of Modeling Error in Multi-Scale Modeling of Heterogeneous Elastic Solids  

E-Print Network [OSTI]

Global Enhancement . . . . . . . . . . . . . . . . . . . . 24 3.3.3 The Adaptive Process . . . . . . . . . . . . . . . . . . . 24 Chapter 4. Modeling Error Estimation 30 4.1 Residual-Based Error Estimation . . . . . . . . . . . . . . . . . 30 4.2 Error... with effectivity indices . 80 ix 5.18 Average estimates of enhancement errors in quantity of interest Qx(u) using three enhancements with effectivity indices . . . . 80 x List of Figures 1.1 Examples of composite failure modes . . . . . . . . . . . . . . 4 2...

Moody, Tristan

2008-03-19T23:59:59.000Z

90

Multiscale Simulation Framework for Coupled Fluid Flow and Mechanical Deformation  

SciTech Connect (OSTI)

A multiscale linear-solver framework for the pressure equation associated with flow in highly heterogeneous porous formations was developed. The multiscale based approach is cast in a general algebraic form, which facilitates integration of the new scalable linear solver in existing flow simulators. The Algebraic Multiscale Solver (AMS) is employed as a preconditioner within a multi-stage strategy. The formulations investigated include the standard MultiScale Finite-Element (MSFE) andMultiScale Finite-Volume (MSFV) methods. The local-stage solvers include incomplete factorization and the so-called Correction Functions (CF) associated with the MSFV approach. Extensive testing of AMS, as an iterative linear solver, indicate excellent convergence rates and computational scalability. AMS compares favorably with advanced Algebraic MultiGrid (AMG) solvers for highly detailed three-dimensional heterogeneous models. Moreover, AMS is expected to be especially beneficial in solving time-dependent problems of coupled multiphase flow and transport in large-scale subsurface formations.

Tchelepi, Hamdi

2014-11-14T23:59:59.000Z

91

On-line Chemistry within WRF: Description and Evaluation of a State-of-the-Art Multiscale Air Quality and Weather Prediction Model  

SciTech Connect (OSTI)

This is a conference proceeding that is now being put together as a book. This is chapter 2 of the book: "INTEGRATED SYSTEMS OF MESO-METEOROLOGICAL AND CHEMICAL TRANSPORT MODELS" published by Springer. The chapter title is "On-line Chemistry within WRF: Description and Evaluation of a State-of-the-Art Multiscale Air Quality and Weather Prediction Model." The original conference was the COST-728/NetFAM workshop on Integrated systems of meso-meteorological and chemical transport models, Danish Meteorological Institute, Copenhagen, May 21-23, 2007.

Grell, Georg; Fast, Jerome D.; Gustafson, William I.; Peckham, Steven E.; McKeen, Stuart A.; Salzmann, Marc; Freitas, Saulo

2010-01-01T23:59:59.000Z

92

Simulated diurnal rainfall physics in a multi-scale global climate model with embedded explicit convection  

E-Print Network [OSTI]

their Community Earth System Model (Richard Neale, personaldevelopment of Earth system models capable of reproducing

Pritchard, Michael Stephen

2011-01-01T23:59:59.000Z

93

Multiscale Geometry of the Olsen Model and Non-Classical Relaxation Oscillations  

E-Print Network [OSTI]

We study the Olsen model for the peroxidase-oxidase reaction. The dynamics is analyzed using a geometric decomposition based upon multiple time scales. The Olsen model is four-dimensional, not in a standard form required by geometric singular perturbation theory and contains multiple small parameters. These three obstacles are the main challenges we resolve by our analysis. Scaling and the blow-up method are used to identify several subsystems. The results presented here provide a rigorous analysis for two oscillatory modes. In particular, we prove the existence of non-classical relaxation oscillations in two cases. The analysis is based upon desingularization of lines of transcritical and submanifolds of fold singularities in combination with an integrable relaxation phase. In this context our analysis also explains an assumption that has been utilized, based purely on numerical reasoning, in a previous bifurcation analysis by Desroches, Krauskopf and Osinga [{Discret.}{Contin.}{Dyn.}{Syst.}S, 2(4), p.807--827, 2009]. Furthermore, the geometric decomposition we develop forms the basis to prove the existence of mixed-mode and chaotic oscillations in the Olsen model, which will be discussed in more detail in future work.

Christian Kuehn; Peter Szmolyan

2014-06-22T23:59:59.000Z

94

A parallel and multiscale strategy for the parametric study of transient dynamic problems with friction  

E-Print Network [OSTI]

with friction P.-A. Boucard1, D. Odi`evre1 and F. Gatuingt1 LMT-Cachan (ENS Cachan/CNRS/Universit´e Paris 6/PRES with friction. Our approach is based on the multiscale LATIN method with domain decomposition. This is a mixed; transient dynamics; domain decomposition; contact; friction; parallel processing 1. INTRODUCTION Modeling

95

MULTISCALE PHENOMENA IN MATERIALS  

SciTech Connect (OSTI)

This project developed and supported a technology base in nonequilibrium phenomena underpinning fundamental issues in condensed matter and materials science, and applied this technology to selected problems. In this way the increasingly sophisticated synthesis and characterization available for classes of complex electronic and structural materials provided a testbed for nonlinear science, while nonlinear and nonequilibrium techniques helped advance our understanding of the scientific principles underlying the control of material microstructure, their evolution, fundamental to macroscopic functionalities. The project focused on overlapping areas of emerging thrusts and programs in the Los Alamos materials community for which nonlinear and nonequilibrium approaches will have decisive roles and where productive teamwork among elements of modeling, simulations, synthesis, characterization and applications could be anticipated--particularly multiscale and nonequilibrium phenomena, and complex matter in and between fields of soft, hard and biomimetic materials. Principal topics were: (i) Complex organic and inorganic electronic materials, including hard, soft and biomimetic materials, self-assembly processes and photophysics; (ii) Microstructure and evolution in multiscale and hierarchical materials, including dynamic fracture and friction, dislocation and large-scale deformation, metastability, and inhomogeneity; and (iii) Equilibrium and nonequilibrium phases and phase transformations, emphasizing competing interactions, frustration, landscapes, glassy and stochastic dynamics, and energy focusing.

A. BISHOP

2000-09-01T23:59:59.000Z

96

Viscoelastic Model for Lung Parenchyma for Multi-Scale Modeling of Respiratory System, Phase II: Dodecahedral Micro-Model  

SciTech Connect (OSTI)

In the first year of this contractual effort a hypo-elastic constitutive model was developed and shown to have great potential in modeling the elastic response of parenchyma. This model resides at the macroscopic level of the continuum. In this, the second year of our support, an isotropic dodecahedron is employed as an alveolar model. This is a microscopic model for parenchyma. A hopeful outcome is that the linkage between these two scales of modeling will be a source of insight and inspiration that will aid us in the final year's activity: creating a viscoelastic model for parenchyma.

Freed, Alan D.; Einstein, Daniel R.; Carson, James P.; Jacob, Rick E.

2012-03-01T23:59:59.000Z

97

Multiscale Reservoir Simulation: Layer Design, Full Field Pseudoization and Near Well Modeling  

E-Print Network [OSTI]

In the past decades, considerable effort has been put into developing high resolution geological models for oil and gas reservoirs. Although the growth of computational power is rapid, the static model size still exceeds the model size for routine...

Du, Song

2012-12-10T23:59:59.000Z

98

Modeling, Analysis and Simulation of Multiscale Preferential Flow - 8/05-8/10 - Final Report  

SciTech Connect (OSTI)

The research agenda of this project are: (1) Modeling of preferential transport from mesoscale to macroscale; (2) Modeling of fast flow in narrow fractures in porous media; (3) Pseudo-parabolic Models of Dynamic Capillary Pressure; (4) Adaptive computational upscaling of flow with inertia from porescale to mesoscale; (5) Adaptive modeling of nonlinear coupled systems; and (6) Adaptive modeling and a-posteriori estimators for coupled systems with heterogeneous data.

Ralph Showalter; Malgorzata Peszynska

2012-07-03T23:59:59.000Z

99

Multiscale Simulations for Polymeric Flow  

E-Print Network [OSTI]

Multiscale simulation methods have been developed based on the local stress sampling strategy and applied to three flow problems with different difficulty levels: (a) general flow problems of simple fluids, (b) parallel (one-dimensional) flow problems of polymeric liquids, and (c) general (two- or three-dimensional) flow problems of polymeric liquids. In our multiscale methods, the local stress of each fluid element is calculated directly by performing microscopic or mesoscopic simulations according to the local flow quantities instead of using any constitutive relations. For simple fluids (a), such as the Lenard-Jones liquid, a multiscale method combining MD and CFD simulations is developed based on the local equilibrium assumption without memories of the flow history. (b), the multiscale method is extended to take into account the memory effects that arise in hydrodynamic stress due to the slow relaxation of polymer-chain conformations. The memory of polymer dynamics on each fluid element is thus resolved by performing MD simulations in which cells are fixed at the mesh nodes of the CFD simulations.For general (two- or three-dimensional) flow problems of polymeric liquids (c), it is necessary to trace the history of microscopic information such as polymer-chain conformation, which carries the memories of past flow history, along the streamline of each fluid element. A Lagrangian-based CFD is thus implemented to correctly advect the polymer-chain conformation consistently with the flow. On each fluid element, coarse-grained polymer simulations are carried out to consider the dynamics of entangled polymer chains that show extremely slow relaxation compared to microscopic time scales.

Takahiro Murashima; Takashi Taniguchi; Ryoichi Yamamoto; Shugo Yasuda

2011-01-06T23:59:59.000Z

100

Parametric vertical coordinate formulation for multiscale, Boussinesq, and non-Boussinesq ocean modeling  

E-Print Network [OSTI]

, but more faithfully represents satellite-observed ocean- bottom-pressure data. Such a generalized modeling coastal ocean predictions, climate simulations, data assimilations, and coupled physical

Hou, Thomas Yizhao

Note: This page contains sample records for the topic "method multiscale modeling" 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

The Radiative Properties of Small Clouds: Multi-Scale Observations and Modeling  

SciTech Connect (OSTI)

Warm, liquid clouds and their representation in climate models continue to represent one of the most significant unknowns in climate sensitivity and climate change. Our project combines ARM observations, LES modeling, and satellite imagery to characterize shallow clouds and the role of aerosol in modifying their radiative effects.

Feingold, Graham [NOAA ESRL; McComiskey, Allison [CIRES, University of Colorado

2013-09-25T23:59:59.000Z

102

Multiscale micromechanical modeling of the thermal/mechanical properties of polymer/clay nanocomposites  

E-Print Network [OSTI]

Polymer/clay nanocomposites have been observed to exhibit enhanced thermal/mechanical properties at low weight fractions (We) of clay. Continuum-based composite modeling reveals that the enhanced properties are strongly ...

Sheng, Nuo, 1977-

2006-01-01T23:59:59.000Z

103

A multi-scale iterative approach for finite element modeling of thermal contact resistance  

E-Print Network [OSTI]

Surface topography has long been considered a key factor in the performance of many contact applications including thermal contact resistance. However, essentially all analytical and numerical models of thermal contact ...

Thompson, Mary Kathryn, 1980-

2007-01-01T23:59:59.000Z

104

Development of a multi-scale projection method with immersed boundaries for chemically reactive flows and its application to examine flame stabilization and blow-off mechanisms  

E-Print Network [OSTI]

High-fidelity multi-scale simulation tools are critically important for examining energy conversion processes in which the coupling of complex chemical kinetics, molecular transport, continuum mixing and acoustics play ...

Kedia, Kushal Sharad

2013-01-01T23:59:59.000Z

105

Hydraulic Fracture: multiscale processes and moving  

E-Print Network [OSTI]

Hydraulic Fracture: multiscale processes and moving interfaces Anthony Peirce Department Siebrits (SLB, Houston) #12;2 Outline · What is a hydraulic fracture? · Mathematical models of hydraulic fracture · Scaling and special solutions for 1-2D models · Numerical modeling for 2-3D problems

Peirce, Anthony

106

A multiscale mechanobiological model of bone remodelling predicts site-specific bone loss in the femur during osteoporosis and mechanical disuse  

E-Print Network [OSTI]

We propose a multiscale mechanobiological model of bone remodelling to investigate the site-specific evolution of bone volume fraction across the midshaft of a femur. The model includes hormonal regulation and biochemical coupling of bone cell populations, the influence of the microstructure on bone turnover rate, and mechanical adaptation of the tissue. Both microscopic and tissue-scale stress/strain states of the tissue are calculated from macroscopic loads by a combination of beam theory and micromechanical homogenisation. This model is applied to simulate the spatio-temporal evolution of a human midshaft femur scan subjected to two deregulating circumstances: (i) osteoporosis and (ii) mechanical disuse. Both simulated deregulations led to endocortical bone loss, cortical wall thinning and expansion of the medullary cavity, in accordance with experimental findings. Our model suggests that these observations are attributable to a large extent to the influence of the microstructure on bone turnover rate. Mec...

Lerebours, C; Scheiner, S; Pivonka, P

2015-01-01T23:59:59.000Z

107

Homogenization of a Multiscale Viscoelastic Model with Nonlocal Damping, Application to the Human Lungs  

E-Print Network [OSTI]

]. Our motiva- tion concerns the mathematical modeling of the human respiratory system and our interest an abstract convergence condition on this nonlocal operator. We derive some mechanical properties of the limit of air through the respiratory tract from its ex- ternal entries, the nose and the mouth. During

Paris-Sud XI, Université de

108

Understanding Creep Mechanisms in Graphite with Experiments, Multiscale Simulations, and Modeling  

SciTech Connect (OSTI)

Disordering mechanisms in graphite have a long history with conflicting viewpoints. Using Raman and x-ray photon spectroscoy, electron microscopy, x-ray diffraction experiments and atomistic modeling and simulations, the current project has developed a fundamental understanding of early-to-late state radiation damage mechanisms in nuclear reactor grade graphite (NBG-18 and PCEA). We show that the topological defects in graphite play an important role under neutron and ion irradiation.

Eapen, Jacob; Murty, Korukonda; Burchell, Timothy

2014-06-02T23:59:59.000Z

109

Parallel multiscale simulations of a brain aneurysm  

SciTech Connect (OSTI)

Cardiovascular pathologies, such as a brain aneurysm, are affected by the global blood circulation as well as by the local microrheology. Hence, developing computational models for such cases requires the coupling of disparate spatial and temporal scales often governed by diverse mathematical descriptions, e.g., by partial differential equations (continuum) and ordinary differential equations for discrete particles (atomistic). However, interfacing atomistic-based with continuum-based domain discretizations is a challenging problem that requires both mathematical and computational advances. We present here a hybrid methodology that enabled us to perform the first multiscale simulations of platelet depositions on the wall of a brain aneurysm. The large scale flow features in the intracranial network are accurately resolved by using the high-order spectral element Navier–Stokes solver N??T?r. The blood rheology inside the aneurysm is modeled using a coarse-grained stochastic molecular dynamics approach (the dissipative particle dynamics method) implemented in the parallel code LAMMPS. The continuum and atomistic domains overlap with interface conditions provided by effective forces computed adaptively to ensure continuity of states across the interface boundary. A two-way interaction is allowed with the time-evolving boundary of the (deposited) platelet clusters tracked by an immersed boundary method. The corresponding heterogeneous solvers (N??T?r and LAMMPS) are linked together by a computational multilevel message passing interface that facilitates modularity and high parallel efficiency. Results of multiscale simulations of clot formation inside the aneurysm in a patient-specific arterial tree are presented. We also discuss the computational challenges involved and present scalability results of our coupled solver on up to 300 K computer processors. Validation of such coupled atomistic-continuum models is a main open issue that has to be addressed in future work.

Grinberg, Leopold [Division of Applied Mathematics, Brown University, Providence, RI 02912 (United States)] [Division of Applied Mathematics, Brown University, Providence, RI 02912 (United States); Fedosov, Dmitry A. [Institute of Complex Systems and Institute for Advanced Simulation, Forschungszentrum Jülich, Jülich 52425 (Germany)] [Institute of Complex Systems and Institute for Advanced Simulation, Forschungszentrum Jülich, Jülich 52425 (Germany); Karniadakis, George Em, E-mail: george_karniadakis@brown.edu [Division of Applied Mathematics, Brown University, Providence, RI 02912 (United States)

2013-07-01T23:59:59.000Z

110

Multi-scale Modeling Approach to Acoustic Emission during Plastic Deformation  

E-Print Network [OSTI]

We address the long standing problem of the origin of acoustic emission commonly observed during plastic deformation. We propose a frame-work to deal with the widely separated time scales of collective dislocation dynamics and elastic degrees of freedom to explain the nature of acoustic emission observed during the Portevin-Le Chatelier effect. The Ananthakrishna model is used as it explains most generic features of the phenomenon. Our results show that while acoustic emission bursts correlated with stress drops are well separated for the type C serrations, these bursts merge to form nearly continuous acoustic signals with overriding bursts for the propagating type A bands.

Jagadish Kumar; G. Ananthakrishna

2011-02-20T23:59:59.000Z

111

A Comparison of Simulated Cloud Radar Output from the Multiscale Modeling Framework Global Climate Model with CloudSat Cloud Radar Observations  

SciTech Connect (OSTI)

Over the last few years a new type of global climate model (GCM) has emerged in which a cloud-resolving model is embedded into each grid cell of a GCM. This new approach is frequently called a multiscale modeling framework (MMF) or superparameterization. In this article we present a comparison of MMF output with radar observations from the NASA CloudSat mission, which uses a near-nadir-pointing millimeter-wavelength radar to probe the vertical structure of clouds and precipitation. We account for radar detection limits by simulating the 94 GHz radar reflectivity that CloudSat would observe from the high-resolution cloud-resolving model output produced by the MMF. Overall, the MMF does a good job of reproducing the broad pattern of tropical convergence zones, subtropical belts, and midlatitude storm tracks, as well as their changes in position with the annual solar cycle. Nonetheless, the comparison also reveals a number of model shortfalls including (1) excessive hydrometeor coverage at all altitudes over many convectively active regions, (2) a lack of low-level hydrometeors over all subtropical oceanic basins, (3) excessive low-level hydrometeor coverage (principally precipitating hydrometeors) in the midlatitude storm tracks of both hemispheres during the summer season (in each hemisphere), and (4) a thin band of low-level hydrometeors in the Southern Hemisphere of the central (and at times eastern and western) Pacific in the MMF, which is not observed by CloudSat. This band resembles a second much weaker ITCZ but is restricted to low levels.

Marchand, Roger T.; Haynes, J. M.; Mace, Gerald G.; Ackerman, Thomas P.; Stephens, Graeme L.

2009-01-13T23:59:59.000Z

112

Unified Multiscale Model | EMSL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption by sectorlong version)Underground Natural

113

Multiscale Approach to Protein Engineering in Bioluminescence  

E-Print Network [OSTI]

) Molecular Dynamics (protein) Reduced Modeling (protein/DLSA) #12;Hybrid Quantum Mechanical/Molecular LEVEL TISSUE LEVEL CELLULAR LEVEL SUBCELLULAR LEVEL MOLECULAR LEVEL ATOMIC LEVEL Multiscale in Biology state First excited electronic state Wavelength Absorbance Excitation of DLSA #12;Wavelength 560nm 605

Maryland at College Park, University of

114

Computational upscaled modeling of heterogeneous porous media flow utilizing finite volume method  

E-Print Network [OSTI]

. Finally we will present several applications of the multiscale method in the ?ow in porous media. Problems that we will consider are multiphase immiscible ?ow, multicomponent miscible ?ow, and soil in?ltration in saturated/unsaturated...

Ginting, Victor Eralingga

2005-08-29T23:59:59.000Z

115

An Upwind Finite-Difference Method for Total Variation–Based ...  

E-Print Network [OSTI]

AMS subject classifications. 65D18 ...... We begin by discussing the efficiency improvements we observed by our multiscale method. ..... [14] A. Chambolle, Total variation minimization and a class of binary mrf models, in Proceedings of Energy.

2011-03-17T23:59:59.000Z

116

Utilizing CLASIC observations and multiscale models to study the impact of improved Land surface representation on modeling cloud- convection  

SciTech Connect (OSTI)

The CLASIC experiment was conducted over the US southern great plains (SGP) in June 2007 with an objective to lead an enhanced understanding of the cumulus convection particularly as it relates to land surface conditions. This project was design to help assist with understanding the overall improvement of land atmosphere convection initiation representation of which is important for global and regional models. The study helped address one of the critical documented deficiency in the models central to the ARM objectives for cumulus convection initiation and particularly under summer time conditions. This project was guided by the scientific question building on the CLASIC theme questions: What is the effect of improved land surface representation on the ability of coupled models to simulate cumulus and convection initiation? The focus was on the US Southern Great Plains region. Since the CLASIC period was anomalously wet the strategy has been to use other periods and domains to develop the comparative assessment for the CLASIC data period, and to understand the mechanisms of the anomalous wet conditions on the tropical systems and convection over land. The data periods include the IHOP 2002 field experiment that was over roughly same domain as the CLASIC in the SGP, and some of the DOE funded Ameriflux datasets.

Niyogi, Devdutta S. [Purdue

2013-06-07T23:59:59.000Z

117

Multiscale modeling of fluid transport in heterogeneous materials using discrete Boltzmann methods  

E-Print Network [OSTI]

transport in porous materials like ceramics, concrete, soils, and rocks plays an impor- tant role in many geometries like porous materials. Here, we review some of our previous work and discuss some recent environmental and technological processes [11.For example, the service life and durability of concrete can

Bentz, Dale P.

118

TRAC methods and models. [PWR  

SciTech Connect (OSTI)

The numerical methods and physical models used in the Transient Reactor Analysis Code (TRAC) versions PD2 and PF1 are discussed. Particular emphasis is placed on TRAC-PF1, the version specifically designed to analyze small-break loss-of-coolant accidents (LOCAs).

Mahaffy, J.H.; Liles, D.R.; Bott, T.F.

1981-01-01T23:59:59.000Z

119

Shell model Monte Carlo methods  

SciTech Connect (OSTI)

We review quantum Monte Carlo methods for dealing with large shell model problems. These methods reduce the imaginary-time many-body evolution operator to a coherent superposition of one-body evolutions in fluctuating one-body fields; resultant path integral is evaluated stochastically. We first discuss the motivation, formalism, and implementation of such Shell Model Monte Carlo methods. There then follows a sampler of results and insights obtained from a number of applications. These include the ground state and thermal properties of pf-shell nuclei, thermal behavior of {gamma}-soft nuclei, and calculation of double beta-decay matrix elements. Finally, prospects for further progress in such calculations are discussed. 87 refs.

Koonin, S.E. [California Inst. of Tech., Pasadena, CA (United States). W.K. Kellogg Radiation Lab.; Dean, D.J. [Oak Ridge National Lab., TN (United States)

1996-10-01T23:59:59.000Z

120

Identifying overlapping communities in social networks using multi-scale local information expansion  

E-Print Network [OSTI]

Most existing approaches for community detection require complete information of the graph in a specific scale, which is impractical for many social networks. We propose a novel algorithm that does not embrace the universal approach but instead of trying to focus on local social ties and modeling multi-scales of social interactions occurring in those networks. Our method for the first time optimizes the topological entropy of a network and uncovers communities through a novel dynamic system converging to a local minimum by simply updating the membership vector with very low computational complexity. It naturally supports overlapping communities through associating each node with a membership vector which describes node's involvement in each community. This way, in addition to uncover overlapping communities, we can also describe different multi-scale partitions by tuning the characteristic size of modules from the optimal partition. Because of the high efficiency and accuracy of the algorithm, it is feasible ...

Li, Hui-Jia; Liu, Zhi-Ping; Chen, Luonan; Zhang, Xiang-Sun

2015-01-01T23:59:59.000Z

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121

On the Diurnal Cycle of Deep Convection, High-Level Cloud, and Upper Troposphere Water Vapor in the Multiscale Modeling Framework  

SciTech Connect (OSTI)

The Multiscale Modeling Framework (MMF), also called ‘‘superparameterization’’, embeds a cloud-resolving model (CRM) at each grid column of a general circulation model to replace traditional parameterizations of moist convection and large-scale condensation. This study evaluates the diurnal cycle of deep convection, high-level clouds, and upper troposphere water vapor by applying an infrared (IR) brightness temperature (Tb) and a precipitation radar (PR) simulator to the CRM column data. Simulator results are then compared with IR radiances from geostationary satellites and PR reflectivities from the Tropical Rainfall Measuring Mission (TRMM). While the actual surface precipitation rate in the MMF has a reasonable diurnal phase and amplitude when compared with TRMM observations, the IR simulator results indicate an inconsistency in the diurnal anomalies of high-level clouds between the model and the geostationary satellite data. Primarily because of its excessive high-level clouds, the MMF overestimates the simulated precipitation index (PI) and fails to reproduce the observed diurnal cycle phase relationships among PI, high-level clouds, and upper troposphere relative humidity. The PR simulator results show that over the tropical oceans, the occurrence fraction of reflectivity in excess of 20 dBZ is almost 1 order of magnitude larger than the TRMM data especially at altitudes above 6 km. Both results suggest that the MMF oceanic convection is overactive and possible reasons for this bias are discussed. However, the joint distribution of simulated IR Tb and PR reflectivity indicates that the most intense deep convection is found more often over tropical land than ocean, in agreement with previous observational studies.

Zhang, Yunyan; Klein, Stephen A.; Liu, Chuntao; Tian, Baijun; Marchand, Roger T.; Haynes, J. M.; McCoy, Renata; Zhang, Yuying; Ackerman, Thomas P.

2008-08-22T23:59:59.000Z

122

MULTISCALE MATHEMATICS FOR BIOMASS CONVERSION TO RENEWABLE HYDROGEN  

SciTech Connect (OSTI)

The overall objective of this project is to develop multiscale models for understanding and eventually designing complex processes for renewables. To the best of our knowledge, our work is the first attempt at modeling complex reacting systems, whose performance relies on underlying multiscale mathematics. Our specific application lies at the heart of biofuels initiatives of DOE and entails modeling of catalytic systems, to enable economic, environmentally benign, and efficient conversion of biomass into either hydrogen or valuable chemicals. Specific goals include: (i) Development of rigorous spatio-temporal coarse-grained kinetic Monte Carlo (KMC) mathematics and simulation for microscopic processes encountered in biomass transformation. (ii) Development of hybrid multiscale simulation that links stochastic simulation to a deterministic partial differential equation (PDE) model for an entire reactor. (iii) Development of hybrid multiscale simulation that links KMC simulation with quantum density functional theory (DFT) calculations. (iv) Development of parallelization of models of (i)-(iii) to take advantage of Petaflop computing and enable real world applications of complex, multiscale models. In this NCE period, we continued addressing these objectives and completed the proposed work. Main initiatives, key results, and activities are outlined.

Vlachos, Dionisios; Plechac, Petr; Katsoulakis, Markos

2013-09-05T23:59:59.000Z

123

Study of Multi-Scale Cloud Processes Over the Tropical Western Pacific Using Cloud-Resolving Models Constrained by Satellite Data  

SciTech Connect (OSTI)

Clouds in the tropical western Pacific are an integral part of the large scale environment. An improved understanding of the multi-scale structure of clouds and their interactions with the environment is critical to the ARM (Atmospheric Radiation Measurement) program for developing and evaluating cloud parameterizations, understanding the consequences of model biases, and providing a context for interpreting the observational data collected over the ARM Tropical Western Pacific (TWP) sites. Three-dimensional cloud resolving models (CRMs) are powerful tools for developing and evaluating cloud parameterizations. However, a significant challenge in using CRMs in the TWP is that the region lacks conventional data, so large uncertainty exists in defining the large-scale environment for clouds. This project links several aspects of the ARM program, from measurements to providing improved analyses, and from cloud-resolving modeling to climate-scale modeling and parameterization development, with the overall objective to improve the representations of clouds in climate models and to simulate and quantify resolved cloud effects on the large-scale environment. Our objectives will be achieved through a series of tasks focusing on the use of the Weather Research and Forecasting (WRF) model and ARM data. Our approach includes: -- Perform assimilation of COSMIC GPS radio occultation and other satellites products using the WRF Ensemble Kalman Filter assimilation system to represent the tropical large-scale environment at 36 km grid resolution. This high-resolution analysis can be used by the community to derive forcing products for single-column models or cloud-resolving models. -- Perform cloud-resolving simulations using WRF and its nesting capabilities, driven by the improved regional analysis and evaluate the simulations against ARM datasets such as from TWP-ICE to optimize the microphysics parameters for this region. A cirrus study (Mace and co-authors) already exists for TWP-ICE using satellite and ground-based observations. -- Perform numerical experiments using WRF to investigate how convection over tropical islands in the Maritime Continent interacts with large-scale circulation and affects convection in nearby regions. -- Evaluate and apply WRF as a testbed for GCM cloud parameterizations, utilizing the ability of WRF to run on multiple scales (from cloud resolving to global) to isolate resolution and physics issues from dynamical and model framework issues. Key products will be disseminated to the ARM and larger community through distribution of data archives, including model outputs from the data assimilation products and cloud resolving simulations, and publications.

Dudhia, Jimy

2013-03-12T23:59:59.000Z

124

On-line supplement to: SMART: A Stochastic Multi-scale Model for the Analysis of Energy Resources, Tech-  

E-Print Network [OSTI]

turbine, photovoltaic or hydro-power. Age is typically in units of years. Location can be expressed programming model, and a stochastic optimization problem. System state variables We divide the state variable

Powell, Warren B.

125

Viscoelastic Model for Lung Parenchyma for Multi-Scale Modeling of Respiratory System Phase I: Hypo-Elastic Model for CFD Implementation  

SciTech Connect (OSTI)

An isotropic constitutive model for the parenchyma of lung has been derived from the theory of hypo-elasticity. The intent is to use it to represent the mechanical response of this soft tissue in sophisticated, computational, fluid-dynamic models of the lung. This demands that the continuum model be accurate, yet simple and effcient. An objective algorithm for its numeric integration is provided. The response of the model is determined for several boundary-value problems whose experiments are used for material characterization. The effective elastic, bulk, and shear moduli, and Poisson’s ratio, as tangent functions, are also derived. The model is characterized against published experimental data for lung. A bridge between this continuum model and a dodecahedral model of alveolar geometry is investigated, with preliminary findings being reported.

Freed, Alan D.; Einstein, Daniel R.

2011-04-14T23:59:59.000Z

126

Evaluation of the Simulated Interannual and Subseasonal Variability in an AMIP-Style Simulation Using the CSU Multiscale Modeling Framework  

E-Print Network [OSTI]

parameterizations of convection, clouds, and boundary layer with a cloud-resolving model (CRM) embedded into each­style simulation using the 1985­ 2004 sea surface temperature (SST) and sea ice distributions as prescribed a robust MJO and Kelvin and Rossby waves with phase speeds similar to those observed. The geographical

Collett Jr., Jeffrey L.

127

Multiscale Analysis and Optimisation of Photosynthetic Solar Energy Systems  

E-Print Network [OSTI]

This work asks how light harvesting in photosynthetic systems can be optimised for economically scalable, sustainable energy production. Hierarchy theory is introduced as a system-analysis and optimisation tool better able to handle multiscale, multiprocess complexities in photosynthetic energetics compared with standard linear-process analysis. Within this framework, new insights are given into relationships between composition, structure and energetics at the scale of the thylakoid membrane, and also into how components at different scales cooperate under functional objectives of the whole photosynthetic system. Combining these reductionistic and holistic analyses creates a platform for modelling multiscale-optimal, idealised photosynthetic systems in silico.

Andrew K. Ringsmuth

2014-02-24T23:59:59.000Z

128

Multiscale Analysis and Optimisation of Photosynthetic Solar Energy Systems  

E-Print Network [OSTI]

This work asks how light harvesting in photosynthetic systems can be optimised for economically scalable, sustainable energy production. Hierarchy theory is introduced as a system-analysis and optimisation tool better able to handle multiscale, multiprocess complexities in photosynthetic energetics compared with standard linear-process analysis. Within this framework, new insights are given into relationships between composition, structure and energetics at the scale of the thylakoid membrane, and also into how components at different scales cooperate under functional objectives of the whole photosynthetic system. Combining these reductionistic and holistic analyses creates a platform for modelling multiscale-optimal, idealised photosynthetic systems in silico.

Ringsmuth, Andrew K

2014-01-01T23:59:59.000Z

129

Grid adaptation for multiscale plasma simulations Gian Luca Delzanno  

E-Print Network [OSTI]

Grid adaptation for multiscale plasma simulations Gian Luca Delzanno Los Alamos National Laboratory tools need to be developed to bridge the gap between these disparate scales. Grid adaptation is one of such tools, useful to address multiple length scales, and we present a new powerful grid adaptation method

Ito, Atsushi

130

Multi-scale First-Principles Modeling of Three-Phase System of Polymer Electrolyte Membrane Fuel Cel  

SciTech Connect (OSTI)

The three-phase system consisting of Nafion, graphite and platinum in the presence of water is studied using molecule dynamics simulation. The force fields describing the molecular interaction between the components in the system are developed to reproduce the energies calculated from density functional theory modeling. The configuration of such complicated three-phase system is predicted through MD simulations. The nanophase-segregation and transport properties are investigated from the equilibrium state. The coverage of the electrolyte on the platinum surface and the dissolution of oxygen are analyzed.

Brunello, Giuseppe; Choi, Ji; Harvey, David; Jang, Seung

2012-07-01T23:59:59.000Z

131

Design, fabrication and mechanical optimization of multi-scale anisotropic feet for terrestrial locomotion  

E-Print Network [OSTI]

Multi-scale surface interaction methods have been studied to achieve optimal locomotion over surface features of differing length scales. It has been shown that anisotropy is a convenient way of transferring an undirected ...

Morin, Jeffrey W. (Jeffrey William)

2011-01-01T23:59:59.000Z

132

Multi-scale geospatial agroecosystem modeling: a case study on the influence of soil data resolution on carbon budget estimates  

SciTech Connect (OSTI)

The development of effective measures to stabilize atmospheric CO2 concentration and mitigate negative impacts of climate change requires accurate quantification of the spatial variation and magnitude of the terrestrial carbon (C) flux. However, the spatial pattern and strength of terrestrial C sinks and sources remain uncertain. In this study, we designed a spatially-explicit agroecosystem modeling system by integrating the Environmental Policy Integrated Climate (EPIC) model with multiple sources of geospatial and surveyed datasets (including crop type map, elevation, climate forcing, fertilizer application, tillage type and distribution, and crop planting and harvesting date), and applied it to examine the sensitivity of cropland C flux simulations to two widely used soil databases (i.e. State Soil Geographic-STATSGO of a scale of 1:250,000 and Soil Survey Geographic-SSURGO of a scale of 1:24,000) in Iowa, USA. To efficiently execute numerous EPIC runs resulting from the use of high resolution spatial data (56m), we developed a parallelized version of EPIC. Both STATSGO and SSURGO led to similar simulations of crop yields and Net Ecosystem Production (NEP) estimates at the State level. However, substantial differences were observed at the county and sub-county (grid) levels. In general, the fine resolution SSURGO data outperformed the coarse resolution STATSGO data for county-scale crop-yield simulation, and within STATSGO, the area-weighted approach provided more accurate results. Further analysis showed that spatial distribution and magnitude of simulated NEP were more sensitive to the resolution difference between SSURGO and STATSGO at the county or grid scale. For over 60% of the cropland areas in Iowa, the deviations between STATSGO- and SSURGO-derived NEP were larger than 1MgCha(-1)yr(-1), or about half of the average cropland NEP, highlighting the significant uncertainty in spatial distribution and magnitude of simulated C fluxes resulting from differences in soil data resolution.

Zhang, Xuesong; Sahajpal, Ritvik; Manowitz, D.; Zhao, Kaiguang; LeDuc, Stephen D.; Xu, Min; Xiong, Wei; Zhang, Aiping; Izaurralde, Roberto C.; Thomson, Allison M.; West, Tristram O.; Post, W. M.

2014-05-01T23:59:59.000Z

133

Peridynamics as a rigorous coarse-graining of atomistics for multiscale materials design.  

SciTech Connect (OSTI)

This report summarizes activities undertaken during FY08-FY10 for the LDRD Peridynamics as a Rigorous Coarse-Graining of Atomistics for Multiscale Materials Design. The goal of our project was to develop a coarse-graining of finite temperature molecular dynamics (MD) that successfully transitions from statistical mechanics to continuum mechanics. The goal of our project is to develop a coarse-graining of finite temperature molecular dynamics (MD) that successfully transitions from statistical mechanics to continuum mechanics. Our coarse-graining overcomes the intrinsic limitation of coupling atomistics with classical continuum mechanics via the FEM (finite element method), SPH (smoothed particle hydrodynamics), or MPM (material point method); namely, that classical continuum mechanics assumes a local force interaction that is incompatible with the nonlocal force model of atomistic methods. Therefore FEM, SPH, and MPM inherit this limitation. This seemingly innocuous dichotomy has far reaching consequences; for example, classical continuum mechanics cannot resolve the short wavelength behavior associated with atomistics. Other consequences include spurious forces, invalid phonon dispersion relationships, and irreconcilable descriptions/treatments of temperature. We propose a statistically based coarse-graining of atomistics via peridynamics and so develop a first of a kind mesoscopic capability to enable consistent, thermodynamically sound, atomistic-to-continuum (AtC) multiscale material simulation. Peridynamics (PD) is a microcontinuum theory that assumes nonlocal forces for describing long-range material interaction. The force interactions occurring at finite distances are naturally accounted for in PD. Moreover, PDs nonlocal force model is entirely consistent with those used by atomistics methods, in stark contrast to classical continuum mechanics. Hence, PD can be employed for mesoscopic phenomena that are beyond the realms of classical continuum mechanics and atomistic simulations, e.g., molecular dynamics and density functional theory (DFT). The latter two atomistic techniques are handicapped by the onerous length and time scales associated with simulating mesoscopic materials. Simulating such mesoscopic materials is likely to require, and greatly benefit from multiscale simulations coupling DFT, MD, PD, and explicit transient dynamic finite element methods FEM (e.g., Presto). The proposed work fills the gap needed to enable multiscale materials simulations.

Lehoucq, Richard B.; Aidun, John Bahram; Silling, Stewart Andrew; Sears, Mark P.; Kamm, James R.; Parks, Michael L.

2010-09-01T23:59:59.000Z

134

Multi-scale texture analysis of remote sensing images using gabor filter banks and wavelet transforms  

E-Print Network [OSTI]

to texture information extraction and utilization. This research focuses on the use of multi-scale image texture analysis techniques using Gabor filter banks and Wavelet transformations. Gabor filter banks model texture as irradiance patterns in an image over...

Ravikumar, Rahul

2009-05-15T23:59:59.000Z

135

Probabilistic Methods for Model Validation  

E-Print Network [OSTI]

to Galileo’s observation of four moons of Jupiter, and phases of Venus in 1610, and Giovanni Zupi’s observation of phases of Mercury in 1639. Based on the astronomical observation of Tycho Brahe, the Copernicus’s model was refined by Johannes Kepler...

Halder, Abhishek

2014-05-01T23:59:59.000Z

136

Sandia National Laboratories: multiscale modeling  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1developmentturbine bladelifetime ismobile test systeminsideconcentrated solar

137

Multiscale characterization and analysis of shapes  

DOE Patents [OSTI]

An adaptive multiscale method approximates shapes with continuous or uniformly and densely sampled contours, with the purpose of sparsely and nonuniformly discretizing the boundaries of shapes at any prescribed resolution, while at the same time retaining the salient shape features at that resolution. In another aspect, a fundamental geometric filtering scheme using the Constrained Delaunay Triangulation (CDT) of polygonized shapes creates an efficient parsing of shapes into components that have semantic significance dependent only on the shapes' structure and not on their representations per se. A shape skeletonization process generalizes to sparsely discretized shapes, with the additional benefit of prunability to filter out irrelevant and morphologically insignificant features. The skeletal representation of characters of varying thickness and the elimination of insignificant and noisy spurs and branches from the skeleton greatly increases the robustness, reliability and recognition rates of character recognition algorithms.

Prasad, Lakshman (Los Alamos, NM); Rao, Ramana (Sunnyvale, CA)

2002-01-01T23:59:59.000Z

138

Angular multiscale statistics of Lagrangian trajectories in turbulence  

E-Print Network [OSTI]

The angle between subsequent particle displacement increments is evaluated as a function of the timelag in isotropic turbulence. It is shown that the evolution of this angle contains two well-defined power-laws, reflecting the multi-scale dynamics of high-Reynolds number turbulence. The proba-bility density function of the directional change is shown to be self-similar and well approximated by an analytically derived model assuming Gaussianity and independence of the velocity and the Lagrangian acceleration.

Bos, Wouter; Schneider, Kai

2015-01-01T23:59:59.000Z

139

Geoelectrical Measurement of Multi-Scale Mass Transfer Parameters  

SciTech Connect (OSTI)

Mass transfer affects contaminant transport and is thought to control the efficiency of aquifer remediation at a number of sites within the Department of Energy (DOE) complex. An improved understanding of mass transfer is critical to meeting the enormous scientific and engineering challenges currently facing DOE. Informed design of site remedies and long-term stewardship of radionuclide-contaminated sites will require new cost-effective laboratory and field techniques to measure the parameters controlling mass transfer spatially and across a range of scales. In this project, we sought to capitalize on the geophysical signatures of mass transfer. Previous numerical modeling and pilot-scale field experiments suggested that mass transfer produces a geoelectrical signature—a hysteretic relation between sampled (mobile-domain) fluid conductivity and bulk (mobile + immobile) conductivity—over a range of scales relevant to aquifer remediation. In this work, we investigated the geoelectrical signature of mass transfer during tracer transport in a series of controlled experiments to determine the operation of controlling parameters, and also investigated the use of complex-resistivity (CR) as a means of quantifying mass transfer parameters in situ without tracer experiments. In an add-on component to our grant, we additionally considered nuclear magnetic resonance (NMR) to help parse mobile from immobile porosities. Including the NMR component, our revised study objectives were to: 1. Develop and demonstrate geophysical approaches to measure mass-transfer parameters spatially and over a range of scales, including the combination of electrical resistivity monitoring, tracer tests, complex resistivity, nuclear magnetic resonance, and materials characterization; and 2. Provide mass-transfer estimates for improved understanding of contaminant fate and transport at DOE sites, such as uranium transport at the Hanford 300 Area. To achieve our objectives, we implemented a 3-part research plan involving (1) development of computer codes and techniques to estimate mass-transfer parameters from time-lapse electrical data; (2) bench-scale experiments on synthetic materials and materials from cores from the Hanford 300 Area; and (3) field demonstration experiments at the DOE’s Hanford 300 Area. In a synergistic add-on to our workplan, we analyzed data from field experiments performed at the DOE Naturita Site under a separate DOE SBR grant, on which PI Day-Lewis served as co-PI. Techniques developed for application to Hanford datasets also were applied to data from Naturita. 1. Introduction The Department of Energy (DOE) faces enormous scientific and engineering challenges associated with the remediation of legacy contamination at former nuclear weapons production facilities. Selection, design and optimization of appropriate site remedies (e.g., pump-and-treat, biostimulation, or monitored natural attenuation) requires reliable predictive models of radionuclide fate and transport; however, our current modeling capabilities are limited by an incomplete understanding of multi-scale mass transfer—its rates, scales, and the heterogeneity of controlling parameters. At many DOE sites, long “tailing” behavior, concentration rebound, and slower-than-expected cleanup are observed; these observations are all consistent with multi-scale mass transfer [Haggerty and Gorelick, 1995; Haggerty et al., 2000; 2004], which renders pump-and-treat remediation and biotransformation inefficient and slow [Haggerty and Gorelick, 1994; Harvey et al., 1994; Wilson, 1997]. Despite the importance of mass transfer, there are significant uncertainties associated with controlling parameters, and the prevalence of mass transfer remains a point of debate [e.g., Hill et al., 2006; Molz et al., 2006] for lack of experimental methods to verify and measure it in situ or independently of tracer breakthrough. There is a critical need for new field-experimental techniques to measure mass transfer in-situ and estimate multi-scale and spatially variable mass-transfer parame

Day-Lewis, Frederick; Singha, Kamini; Haggerty, Roy; Johnson, Tim; Binley, Andrew; Lane, John

2014-01-16T23:59:59.000Z

140

Multi-scale modeling of Puget Sound using an unstructured-grid coastal ocean model: from tide flats to estuaries and coastal waters  

SciTech Connect (OSTI)

Water circulation in Puget Sound, a large complex estuary system in the Pacific Northwest coastal ocean of the United States, is governed by multiple spatially and temporally varying forcings from tides, atmosphere (wind, heating/cooling, precipitation/evaporation, pressure), and river inflows. In addition, the hydrodynamic response is affected strongly by geomorphic features, such as fjord-like bathymetry and complex shoreline features, resulting in many distinguishing characteristics in its main and sub-basins. To better understand the details of circulation features in Puget Sound and to assist with proposed nearshore restoration actions for improving water quality and the ecological health of Puget Sound, a high-resolution (around 50 m in estuaries and tide flats) hydrodynamic model for the entire Puget Sound was needed. Here, a threedimensional circulation model of Puget Sound using an unstructured-grid finite volume coastal ocean model is presented. The model was constructed with sufficient resolution in the nearshore region to address the complex coastline, multi-tidal channels, and tide flats. Model open boundaries were extended to the entrance of the Strait of Juan de Fuca and the northern end of the Strait of Georgia to account for the influences of ocean water intrusion from the Strait of Juan de Fuca and the Fraser River plume from the Strait of Georgia, respectively. Comparisons of model results, observed data, and associated error statistics for tidal elevation, velocity, temperature, and salinity indicate that the model is capable of simulating the general circulation patterns on the scale of a large estuarine system as well as detailed hydrodynamics in the nearshore tide flats. Tidal characteristics, temperature/salinity stratification, mean circulation, and river plumes in estuaries with tide flats are discussed.

Yang, Zhaoqing; Khangaonkar, Tarang

2010-11-19T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

Multitier Multiscale Sensing: a new paradigm for actuated sensing  

E-Print Network [OSTI]

tier multiscale architecture Environmental phenomena Firstmultiscale architecture Environmental phenomena First Tier:

2007-01-01T23:59:59.000Z

142

Tuning Methods for Model Predictive Controllers  

E-Print Network [OSTI]

methods for tuning of a Gas-Oil Furnace, a Wood-Berry Distillation Column and a Cement Mill Circuit. #12-M.Sc.-2012-69 #12;Summary (English) Model Predictive Control (MPC) is an optimal control strategy, and can-Berry distillations kolonne og en cement mølle proces. #12;iv #12;Preface This M. Sc. thesis was prepared

143

Multiscale eddy simulation for moist atmospheric convection: Preliminary investigation  

SciTech Connect (OSTI)

A multiscale computational framework is designed for simulating atmospheric convection and clouds. In this multiscale framework, large eddy simulation (LES) is used to model the coarse scales of 100 m and larger, and a stochastic, one-dimensional turbulence (ODT) model is used to represent the fine scales of 100 m and smaller. Coupled and evolving together, these two components provide a multiscale eddy simulation (MES). Through its fine-scale turbulence and moist thermodynamics, MES allows coarse grid cells to be partially cloudy and to encompass cloudy–clear air mixing on scales down to 1 m; in contrast, in typical LES such fine-scale processes are not represented or are parameterized using bulk deterministic closures. To illustrate MES and investigate its multiscale dynamics, a shallow cumulus cloud field is simulated. The fine-scale variability is seen to take a plausible form, with partially cloudy grid cells prominent near cloud edges and cloud top. From earlier theoretical work, this mixing of cloudy and clear air is believed to have an important impact on buoyancy. However, contrary to expectations based on earlier theoretical studies, the mean statistics of the bulk cloud field are essentially the same in MES and LES; possible reasons for this are discussed, including possible limitations in the present formulation of MES. One difference between LES and MES is seen in the coarse-scale turbulent kinetic energy, which appears to grow slowly in time due to incoherent stochastic fluctuations in the buoyancy. This and other considerations suggest the need for some type of spatial and/or temporal filtering to attenuate undersampling of the stochastic fine-scale processes.

Stechmann, Samuel N., E-mail: stechmann@wisc.edu [Department of Mathematics, University of Wisconsin-Madison (United States); Department of Atmospheric and Oceanic Sciences, University of Wisconsin-Madison (United States)

2014-08-15T23:59:59.000Z

144

Method and apparatus for modeling interactions  

DOE Patents [OSTI]

A method and apparatus for modeling interactions between bodies. The method comprises representing two bodies undergoing translations and rotations by two hierarchical swept volume representations. Interactions such as nearest approach and collision can be modeled based on the swept body representations. The present invention can serve as a practical tool in motion planning, CAD systems, simulation systems, safety analysis, and applications that require modeling time-based interactions. A body can be represented in the present invention by a union of convex polygons and convex polyhedra. As used generally herein, polyhedron includes polygon, and polyhedra includes polygons. The body undergoing translation can be represented by a swept body representation, where the swept body representation comprises a hierarchical bounding volume representation whose leaves each contain a representation of the region swept by a section of the body during the translation, and where the union of the regions is a superset of the region swept by the surface of the body during translation. Interactions between two bodies thus represented can be modeled by modeling interactions between the convex hulls of the finite sets of discrete points in the swept body representations.

Xavier, Patrick G. (Albuquerque, NM)

2000-08-08T23:59:59.000Z

145

Adaptive model training system and method  

DOE Patents [OSTI]

An adaptive model training system and method for filtering asset operating data values acquired from a monitored asset for selectively choosing asset operating data values that meet at least one predefined criterion of good data quality while rejecting asset operating data values that fail to meet at least the one predefined criterion of good data quality; and recalibrating a previously trained or calibrated model having a learned scope of normal operation of the asset by utilizing the asset operating data values that meet at least the one predefined criterion of good data quality for adjusting the learned scope of normal operation of the asset for defining a recalibrated model having the adjusted learned scope of normal operation of the asset.

Bickford, Randall L; Palnitkar, Rahul M

2014-11-18T23:59:59.000Z

146

Adaptive model training system and method  

DOE Patents [OSTI]

An adaptive model training system and method for filtering asset operating data values acquired from a monitored asset for selectively choosing asset operating data values that meet at least one predefined criterion of good data quality while rejecting asset operating data values that fail to meet at least the one predefined criterion of good data quality; and recalibrating a previously trained or calibrated model having a learned scope of normal operation of the asset by utilizing the asset operating data values that meet at least the one predefined criterion of good data quality for adjusting the learned scope of normal operation of the asset for defining a recalibrated model having the adjusted learned scope of normal operation of the asset.

Bickford, Randall L; Palnitkar, Rahul M; Lee, Vo

2014-04-15T23:59:59.000Z

147

Multiscale thermal transport.  

SciTech Connect (OSTI)

A concurrent computational and experimental investigation of thermal transport is performed with the goal of improving understanding of, and predictive capability for, thermal transport in microdevices. The computational component involves Monte Carlo simulation of phonon transport. In these simulations, all acoustic modes are included and their properties are drawn from a realistic dispersion relation. Phonon-phonon and phonon-boundary scattering events are treated independently. A new set of phonon-phonon scattering coefficients are proposed that reflect the elimination of assumptions present in earlier analytical work from the simulation. The experimental component involves steady-state measurement of thermal conductivity on silicon films as thin as 340nm at a range of temperatures. Agreement between the experiment and simulation on single-crystal silicon thin films is excellent, Agreement for polycrystalline films is promising, but significant work remains to be done before predictions can be made confidently. Knowledge gained from these efforts was used to construct improved semiclassical models with the goal of representing microscale effects in existing macroscale codes in a computationally efficient manner.

Graham, Samuel Jr. (; .); Wong, C. C.; Piekos, Edward Stanley

2004-02-01T23:59:59.000Z

148

Multiscale mechanics of macromolecular materials with unfolding domains  

E-Print Network [OSTI]

We propose a general multiscale approach for the mechanical behavior of three-dimensional networks of macromolecules undergoing strain-induced unfolding. Starting from a (statistically based) energetic analysis of the macromolecule unfolding strategy, we obtain a three-dimensional continuum model with variable natural configuration and an energy function analytically deduced from the microscale material parameters. The comparison with the experiments shows the ability of the model to describe the complex behavior, with residual stretches and unfolding effects, observed in different biological materials.

Domenico De Tommasi; Giuseppe Puglisi; Giuseppe Saccomandi

2014-07-14T23:59:59.000Z

149

Method of and apparatus for modeling interactions  

DOE Patents [OSTI]

A method and apparatus for modeling interactions can accurately model tribological and other properties and accommodate topological disruptions. Two portions of a problem space are represented, a first with a Lagrangian mesh and a second with an ALE mesh. The ALE and Lagrangian meshes are constructed so that each node on the surface of the Lagrangian mesh is in a known correspondence with adjacent nodes in the ALE mesh. The interaction can be predicted for a time interval. Material flow within the ALE mesh can accurately model complex interactions such as bifurcation. After prediction, nodes in the ALE mesh in correspondence with nodes on the surface of the Lagrangian mesh can be mapped so that they are once again adjacent to their corresponding Lagrangian mesh nodes. The ALE mesh can then be smoothed to reduce mesh distortion that might reduce the accuracy or efficiency of subsequent prediction steps. The process, from prediction through mapping and smoothing, can be repeated until a terminal condition is reached.

Budge, Kent G.

2004-01-13T23:59:59.000Z

150

Formal Support for an Informal Business Modelling Method \\Lambda  

E-Print Network [OSTI]

Formal Support for an Informal Business Modelling Method \\Lambda Yun­Heh Chen­Burger, David emails: jessicac@dai.ed.ac.uk, dr@dai.ed.ac.uk September 1, 1998 Abstract Business modelling methods modelling method: IBM's Business System Devel­ opment Method (BSDM). We describe the knowledge which we

Chen-Burger, Yun-Heh (Jessica)

151

Computer Aided Multi-scale Design of SiC-Si3N4 Nanoceramic Composites for High-Temperature Structural Applications  

SciTech Connect (OSTI)

It is estimated that by using better and improved high temperature structural materials, the power generation efficiency of the power plants can be increased by 15% resulting in significant cost savings. One such promising material system for future high-temperature structural applications in power plants is Silicon Carbide-Silicon Nitride (SiC-Si{sub 3}N{sub 4}) nanoceramic matrix composites. The described research work focuses on multiscale simulation-based design of these SiC-Si{sub 3}N{sub 4} nanoceramic matrix composites. There were two primary objectives of the research: (1) Development of a multiscale simulation tool and corresponding multiscale analyses of the high-temperature creep and fracture resistance properties of the SiC-Si{sub 3}N{sub 4} nanocomposites at nano-, meso- and continuum length- and timescales; and (2) Development of a simulation-based robust design optimization methodology for application to the multiscale simulations to predict the range of the most suitable phase morphologies for the desired high-temperature properties of the SiC-Si{sub 3}N{sub 4} nanocomposites. The multiscale simulation tool is based on a combination of molecular dynamics (MD), cohesive finite element method (CFEM), and continuum level modeling for characterizing time-dependent material deformation behavior. The material simulation tool is incorporated in a variable fidelity model management based design optimization framework. Material modeling includes development of an experimental verification framework. Using material models based on multiscaling, it was found using molecular simulations that clustering of the SiC particles near Si{sub 3}N{sub 4} grain boundaries leads to significant nanocomposite strengthening and significant rise in fracture resistance. It was found that a control of grain boundary thicknesses by dispersing non-stoichiometric carbide or nitride phases can lead to reduction in strength however significant rise in fracture strength. The temperature dependent strength and microstructural stability was also significantly depended upon the dispersion of new phases at grain boundaries. The material design framework incorporates high temperature creep and mechanical strength data in order to develop a collaborative multiscale framework of morphology optimization. The work also incorporates a computer aided material design dataset development procedure where a systematic dataset on material properties and morphology correlation could be obtained depending upon a material processing scientist's requirements. Two different aspects covered under this requirement are: (1) performing morphology related analyses at the nanoscale and at the microscale to develop a multiscale material design and analyses capability; (2) linking material behavior analyses with the developed design tool to form a set of material design problems that illustrate the range of material design dataset development that could be performed. Overall, a software based methodology to design microstructure of particle based ceramic nanocomposites has been developed. This methodology has been shown to predict changes in phase morphologies required for achieving optimal balance of conflicting properties such as minimal creep strain rate and high fracture strength at high temperatures. The methodology incorporates complex material models including atomistic approaches. The methodology will be useful to design materials for high temperature applications including those of interest to DoE while significantly reducing cost of expensive experiments.

Vikas Tomer; John Renaud

2010-08-31T23:59:59.000Z

152

Multiscale Detection of Filamentary Features in Image Data Xiaoming Huo1  

E-Print Network [OSTI]

by digital axoids, and (2) the distribution for a point process is replaced by a distribution of intensities contribution is to introduce a general framework in cases when the data is digital. Our detection method can in finite digital situations. Keywords: Multiscale detection of filamentary structures, Digital image

Huo, Xiaoming

153

Adomian Decomposition Method for Quark Gluon Plasma Model  

SciTech Connect (OSTI)

The paper investigates the possibility of obtaining analytical solutions for the Quark Gluon Plasma model using the Adomian decomposition method.

Constantinescu, Radu; Ionescu, Carmen; Stoicescu, Mihai [Dept. of Theoretical Physics, University of Craiova, 13 Al. I. Cuza Str., Craiova, 200 585e (Romania)

2011-10-03T23:59:59.000Z

154

A Multiscale Investigation of Ground Water Flow at Clear Lake, Iowa  

E-Print Network [OSTI]

targets. The model produced ground water inflow and outflow rates of 14,300 and 9200 m3/d, respectively­related problems in the lake and its water- shed, their likely causes, and potential remedial measuresA Multiscale Investigation of Ground Water Flow at Clear Lake, Iowa by William W. Simpkins Abstract

Simpkins, William W.

155

Bayes Linear Uncertainty Analysis for Oil Reservoirs Based on Multiscale Computer Experiments  

E-Print Network [OSTI]

Bayes Linear Uncertainty Analysis for Oil Reservoirs Based on Multiscale Computer Experiments, 2008 1 Introduction Reservoir simulators are important and widely-used tools for oil reservoir for reservoirs, where the model inputs are physical parameters, such as the permeability and porosity of various

Oakley, Jeremy

156

A multi-scale approach to statistical and model-based structural health monitoring with application to embedded sensing for wind energy  

E-Print Network [OSTI]

Simplified Models for Wind Turbine Blades," in 53rd AIAA/in composite wind turbine blades," Journal of IntelligentState estimate of wind turbine blades using geometrically

Taylor, Stuart Glynn

2013-01-01T23:59:59.000Z

157

Hierarchical modeling of multi-scale dynamical systems using adaptive radial basis function neural networks: application to synthetic jet actuator wing  

E-Print Network [OSTI]

is best. More importantly, one might infer that ?it would be nice?, if the approximation approach was inherently adaptive in the sense that the mathematical structure of the approximation method was learned from the data, rather than merely estimating...

Lee, Hee Eun

2004-09-30T23:59:59.000Z

158

A multi-scale approach to statistical and model-based structural health monitoring with application to embedded sensing for wind energy  

E-Print Network [OSTI]

the LIST Wind Turbine," in 2002 ASME Wind Energy Symposium ,from the LIST turbine," in 2001 ASME Wind Energy Symposium ,wind energy production site in the Great Plains. The Micon 65/13 model turbine

Taylor, Stuart Glynn

2013-01-01T23:59:59.000Z

159

June 6, 2007 Large-Scale Scientific Computations'07, Sozopol, Bulgaria -p. 1/29 Multiscale Modeling and Simulation of Fluid  

E-Print Network [OSTI]

in porous media (soil, porous rocks, etc.) x Elasticity problems in composite materials (adobe, concrete/29 Presentation outline s Brief overview of upscaling methods in deformable porous media s The Fluid upscaling of flow in deformable porous media #12;June 6, 2007 Large-Scale Scientific Computations'07

Popov, Peter

160

Copyright c 2002 Tech Science Press CMES, vol.3, no.5, pp.539-555, 2002 Multiscale Modeling of Laser Ablation: Applications to Nanotechnology  

E-Print Network [OSTI]

of Laser Ablation: Applications to Nanotechnology Leonid V. Zhigilei1 and Avinash M. Dongare 1 Abstract-driven methods in nanotechnology. In this pa- per we discuss two computational schemes developed for simulation, applications of laser ablation have been extended into emerging area of nanotechnology. In particular, laser

Zhigilei, Leonid V.

Note: This page contains sample records for the topic "method multiscale modeling" 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

Adaptive Methods for Modelling Transport Processes in Fractured Subsurface Systems  

E-Print Network [OSTI]

­ discrete Galerkin method applying finite differences for the discretization in time and the StreamlineAdaptive Methods for Modelling Transport Processes in Fractured Subsurface Systems 3rd­adaptive methods for modelling transport processes in fractured rock. As a simplification, ideal tracers

Cirpka, Olaf Arie

162

Hydraulic transmissivity and heat exchanges: aperture lowpass filtering model 1 Natural open joints in rocks commonly present multi-scale self-affine apertures. This  

E-Print Network [OSTI]

Hydraulic transmissivity and heat exchanges: aperture lowpass filtering model 1 SUMMARY Natural aperture that describes at best the macroscopic properties (hydraulic conductivity, heat exchange of the effective hydraulic and thermal properties (apertures). A detailed study of the influence of the bandwidth

Paris-Sud XI, Université de

163

An Expectation-Maximization Method for Calibrating Synchronous Machine Models  

SciTech Connect (OSTI)

The accuracy of a power system dynamic model is essential to its secure and efficient operation. Lower confidence in model accuracy usually leads to conservative operation and lowers asset usage. To improve model accuracy, this paper proposes an expectation-maximization (EM) method to calibrate the synchronous machine model using phasor measurement unit (PMU) data. First, an extended Kalman filter (EKF) is applied to estimate the dynamic states using measurement data. Then, the parameters are calculated based on the estimated states using maximum likelihood estimation (MLE) method. The EM method iterates over the preceding two steps to improve estimation accuracy. The proposed EM method’s performance is evaluated using a single-machine infinite bus system and compared with a method where both state and parameters are estimated using an EKF method. Sensitivity studies of the parameter calibration using EM method are also presented to show the robustness of the proposed method for different levels of measurement noise and initial parameter uncertainty.

Meng, Da; Zhou, Ning; Lu, Shuai; Lin, Guang

2013-07-21T23:59:59.000Z

164

Hydraulic Fracture: multiscale processes and moving  

E-Print Network [OSTI]

Hydraulic Fracture: multiscale processes and moving interfaces Anthony Peirce Department Mitchell (UBC) · Ed Siebrits (SLB, Houston) #12;2 Outline · What is a hydraulic fracture? · Scaling Fluid Proppant #12;6 An actual hydraulic fracture #12;7 HF experiment (Jeffrey et al CSIRO) #12;8 1D

Peirce, Anthony

165

Grid adaptation for multiscale plasma simulations  

E-Print Network [OSTI]

Grid adaptation for multiscale plasma simulations Gian Luca Delzanno Los Alamos National Laboratory In collaboration with L. Chacon and J.M. Finn #12;delzanno@lanl.gov Outline · Introduction and motivation · Grid tests · New directions · Conclusions #12;delzanno@lanl.gov Outline · Introduction and motivation · Grid

Ito, Atsushi

166

Simplified methods of modeling multilayer reservoirs  

E-Print Network [OSTI]

during the boundary-dominated flow period. We also examined modeling the pressure response during pseudosteady state flow in a multilayer system with skin factors in individual layers using a single layer solution which includes an equivalent skin factor...

Ryou, Sangsoo

1993-01-01T23:59:59.000Z

167

Introduction to mathematical models and methods  

SciTech Connect (OSTI)

Some well known mathematical models in the form of partial differential equations representing real world systems are introduced along with fundamental concepts of Image Processing. Notions such as seismic texture, seismic attributes, core data, well logging, seismic tomography and reservoirs simulation are discussed.

Siddiqi, A. H.; Manchanda, P. [Gautam Budha University, Gautam Budh Nagar-201310 (India); Department of Mathematics, Guru Nanak Dev University, Amritsar (India)

2012-07-17T23:59:59.000Z

168

Performance Modeling and Access Methods for Temporal Database Management Systems  

E-Print Network [OSTI]

implementation issues. Database systems with temporal support maintain history data on line together with current. Performance Modeling and Access Methods for Temporal Database Management Systems TR86-018 August. #12;Performance Modeling and Access Methods for Temporal Database Management Systems by Ilsoo Ahn

North Carolina at Chapel Hill, University of

169

Utilization of Smart Materials and Predictive Modeling to Integrate Intracellular Dynamics with Cell Biomechanics and Collective Tissue Behavior  

E-Print Network [OSTI]

Utilization of Smart Materials and Predictive Modeling to Integrate Intracellular Dynamics important structures inside cells. New "smart" material will be used to trigger changes to cell movement Medical University Control of Cell Polarization by Smart Material Substrates Multiscale Imaging Multiscale

Mather, Patrick T.

170

1 The Chimera Method for a model problem Franco Brezzi  

E-Print Network [OSTI]

1 The Chimera Method for a model problem Franco Brezzi , Jacques Louis Lions ¡ , and Olivier¥ Universit´e Pierre et Marie Curie pironneau@ann.jussieu.fr 1.1 Introduction The Chimera method [10 around a two-pieces airfoil, namely the solution of ¢¡¤£¦¥ with Dirichlet data by the Chimera method (i

Brezzi, Franco

171

Systems and methods for modeling and analyzing networks  

DOE Patents [OSTI]

The systems and methods described herein utilize a probabilistic modeling framework for reverse engineering an ensemble of causal models, from data and then forward simulating the ensemble of models to analyze and predict the behavior of the network. In certain embodiments, the systems and methods described herein include data-driven techniques for developing causal models for biological networks. Causal network models include computational representations of the causal relationships between independent variables such as a compound of interest and dependent variables such as measured DNA alterations, changes in mRNA, protein, and metabolites to phenotypic readouts of efficacy and toxicity.

Hill, Colin C; Church, Bruce W; McDonagh, Paul D; Khalil, Iya G; Neyarapally, Thomas A; Pitluk, Zachary W

2013-10-29T23:59:59.000Z

172

An Analysis of Web File Sizes: New Methods and Models  

E-Print Network [OSTI]

An Analysis of Web File Sizes: New Methods and Models A Thesis presented by Brent Tworetzky consider such models and how to improve their fits. This thesis contributes to file size research-improved file size estimations over type-blind models. We therefore present a range of useful new file size

Wolfe, Patrick J.

173

Multiscale Modeling of Interface Phenomena in Biology  

E-Print Network [OSTI]

-chemical processes occurring across cellular membranes. Applications will include the study of ion transport across protein membrane channels, the electrical propagation in neurons and neuro-electronic interfaces

174

Multiscale optimization models for powerintensive processes  

E-Print Network [OSTI]

Collaborators: Jose M. Pinto, Praxair Inc., Danbury, CT Nikhil Arora, Praxair Inc., Tonawanda, NY #12;Demand

Grossmann, Ignacio E.

175

Multiscale Modeling and Homogenization of Composite Materials  

E-Print Network [OSTI]

Schematics of fiber composite . . . . . . . . . .of long fiber sic/ti composite materials. Comput. Methodsof Fibre-reinforced composites. Wiley, 4th edition, 2002. [

Mseis, George

2010-01-01T23:59:59.000Z

176

Multiscale stochastic simulations of chemical reactions with regulated scale separation  

SciTech Connect (OSTI)

We present a coupling of multiscale frameworks with accelerated stochastic simulation algorithms for systems of chemical reactions with disparate propensities. The algorithms regulate the propensities of the fast and slow reactions of the system, using alternating micro and macro sub-steps simulated with accelerated algorithms such as ? and R-leaping. The proposed algorithms are shown to provide significant speedups in simulations of stiff systems of chemical reactions with a trade-off in accuracy as controlled by a regulating parameter. More importantly, the error of the methods exhibits a cutoff phenomenon that allows for optimal parameter choices. Numerical experiments demonstrate that hybrid algorithms involving accelerated stochastic simulations can be, in certain cases, more accurate while faster, than their corresponding stochastic simulation algorithm counterparts.

Koumoutsakos, Petros, E-mail: petros@ethz.ch [Chair of Computational Science, Clausiusstrasse 33, ETH Zurich, CH-8092 (Switzerland)] [Chair of Computational Science, Clausiusstrasse 33, ETH Zurich, CH-8092 (Switzerland); Feigelman, Justin [Chair of Computational Science, Clausiusstrasse 33, ETH Zurich, CH-8092 (Switzerland)] [Chair of Computational Science, Clausiusstrasse 33, ETH Zurich, CH-8092 (Switzerland)

2013-07-01T23:59:59.000Z

177

A Multiscale Approach to Mesh-based Surface Tension Flows Nils Thurey Chris Wojtan Markus Gross Greg Turk  

E-Print Network [OSTI]

A Multiscale Approach to Mesh-based Surface Tension Flows Nils Th¨urey Chris Wojtan Markus Gross 1: Our method allows us to efficiently simulate complex surface tension phenomena such as this crown surface tension forces that is free from typical strict time step constraints. The second simulation layer

Frey, Pascal

178

A high-resolution, cloud-assimilating numerical weather prediction model for solar irradiance forecasting  

E-Print Network [OSTI]

Multiscale Numerical Weather Prediction Model.   Progress assimilating numerical weather prediction model for solar customizable  numerical weather prediction model that is 

Mathiesen, Patrick; Collier, Craig; Kleissl, Jan

2013-01-01T23:59:59.000Z

179

Formal Support for an Informal Business Modelling Method   

E-Print Network [OSTI]

Business modelling methods are popular but, since they operate primarily in the early stages of software lifecycles, most are informal. This paper describes how we have used a conventional formal notation (first order predicate logic) in combination...

Chen-Burger, Jessica; Robertson, Dave; Stader, Justine

2000-01-01T23:59:59.000Z

180

Model Error Correction for Linear Methods in PET Neuroreceptor Measurements  

E-Print Network [OSTI]

Model Error Correction for Linear Methods in PET Neuroreceptor Measurements Hongbin Guo address: hguo1@asu.edu (Hongbin Guo) Preprint submitted to NeuroImage December 11, 2008 #12;reached. A new

Renaut, Rosemary

Note: This page contains sample records for the topic "method multiscale modeling" 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

Computational Science and Engineering On-line: an integrated web-based environment for multi-scale  

E-Print Network [OSTI]

Computational Science and Engineering On-line: an integrated web-based environment for multi November 2003) We present a development of an integrated extendable web-based environment called initial efforts are focusing on an integrated environment for multi-scale modelling of complex reacting

Truong, Thanh N.

182

NANO EXPRESS Open Access Multiscale investigation of graphene layers on  

E-Print Network [OSTI]

NANO EXPRESS Open Access Multiscale investigation of graphene layers on 6H-SiC(000-1) Antoine , Cecile Naud2 , Jean-Yves Veuillen2* Abstract In this article, a multiscale investigation of few graphene, the authors show that the UHV growth yields few layer graphene (FLG) with an average thickness given by Auger

Paris-Sud XI, Université de

183

Faculty Position in Multi-scale Manufacturing Technologies  

E-Print Network [OSTI]

-precision additive manufacturing technologies; · multi-scale micro-precision manufacturing; · high throughput. Christian Enz Search Committee Chair E-mail: manufacturing-search@epfl.ch For additional information on EPFLFaculty Position in Multi-scale Manufacturing Technologies at the Ecole polytechnique fédérale de

Psaltis, Demetri

184

Localized Scale Coupling and New Educational Paradigms in Multiscale Mathematics and Science  

SciTech Connect (OSTI)

One of the most challenging multi-scale simulation problems in the area of multi-phase materials is to develop effective computational techniques for the prediction of coalescence and related phenomena involving rupture of a thin liquid film due to the onset of instability driven by van der Waals or other micro-scale attractive forces. Accurate modeling of this process is critical to prediction of the outcome of milling processes for immiscible polymer blends, one of the most important routes to new advanced polymeric materials. In typical situations, the blend evolves into an ?emulsion? of dispersed phase drops in a continuous matrix fluid. Coalescence is then a critical factor in determining the size distribution of the dispersed phase, but is extremely difficult to predict from first principles. The thin film separating two drops may only achieve rupture at dimensions of approximately 10 nm while the drop sizes are 0(10 ?m). It is essential to achieve very accurate solutions for the flow and for the interface shape at both the macroscale of the full drops, and within the thin film (where the destabilizing disjoining pressure due to van der Waals forces is proportional approximately to the inverse third power of the local film thickness, h-3). Furthermore, the fluids of interest are polymeric (through Newtonian) and the classical continuum description begins to fail as the film thins ? requiring incorporation of molecular effects, such as a hybrid code that incorporates a version of coarse grain molecular dynamics within the thin film coupled with a classical continuum description elsewhere in the flow domain. Finally, the presence of surface active additions, either surfactants (in the form of di-block copolymers) or surface-functionalized micro- or nano-scale particles, adds an additional level of complexity, requiring development of a distinct numerical method to predict the nonuniform concentration gradients of these additives that are responsible for Marangoni stresses at the interface. Again, the physical dimensions of these additives may become comparable to the thin film dimensions, requiring an additional layer of multi-scale modeling.

LEAL, L. GARY

2013-06-30T23:59:59.000Z

185

A multivariate quadrature based moment method for supersonic combustion modeling  

E-Print Network [OSTI]

A multivariate quadrature based moment method for supersonic combustion modeling Pratik Donde) of thermochemical variables can be used for accurately computing the combustion source term. Quadrature based- ture method of moments (DQMOM) is well suited for multivariate problems like combustion. Numerical

Raman, Venkat

186

Microwave band gap and cavity mode in spoof-insulator-spoof waveguide with multiscale structured surface  

E-Print Network [OSTI]

We propose a multiscale spoof-insulator-spoof (SIS) waveguide by introducing periodic geometry modulation in the wavelength scale to a SIS waveguide made of perfect electric conductor. The MSIS consists of multiple SIS subcells. The dispersion relationship of the fundamental guided mode of the spoof surface plasmon polaritons (SSPPs) is studied analytically within the small gap approximation. It is shown that the multiscale SIS possesses microwave band gap (MBG) due to the Bragg scattering. The "gap maps" in the design parameter space are provided. We demonstrate that the geometry of the subcells can efficiently adjust the effective refraction index of the elementary SIS and therefore further control the width and the position of the MBG. The results are in good agreement with numerical calculations by the finite element method (FEM). For finite-sized MSIS of given geometry in the millimeter scale, FEM calculations show that the first-order symmetric SSPP mode has zero transmission in the MBG within frequency...

Zhang, Qiang; Han, Dezhuan; Qin, Fei Fei; Zhang, Xiao Ming; Yao, Yong

2015-01-01T23:59:59.000Z

187

Probability of detection models for eddy current NDE methods  

SciTech Connect (OSTI)

The development of probability of detection (POD) models for a variety of nondestructive evaluation (NDE) methods is motivated by a desire to quantify the variability introduced during the process of testing. Sources of variability involved in eddy current methods of NDE include those caused by variations in liftoff, material properties, probe canting angle, scan format, surface roughness and measurement noise. This thesis presents a comprehensive POD model for eddy current NDE. Eddy current methods of nondestructive testing are used widely in industry to inspect a variety of nonferromagnetic and ferromagnetic materials. The development of a comprehensive POD model is therefore of significant importance. The model incorporates several sources of variability characterized by a multivariate Gaussian distribution and employs finite element analysis to predict the signal distribution. The method of mixtures is then used for estimating optimal threshold values. The research demonstrates the use of a finite element model within a probabilistic framework to the spread in the measured signal for eddy current nondestructive methods. Using the signal distributions for various flaw sizes the POD curves for varying defect parameters have been computed. In contrast to experimental POD models, the cost of generating such curves is very low and complex defect shapes can be handled very easily. The results are also operator independent.

Rajesh, S.N.

1993-04-30T23:59:59.000Z

188

Coarse graining methods for spin net and spin foam models  

E-Print Network [OSTI]

We undertake first steps in making a class of discrete models of quantum gravity, spin foams, accessible to a large scale analysis by numerical and computational methods. In particular, we apply Migdal-Kadanoff and Tensor Network Renormalization schemes to spin net and spin foam models based on finite Abelian groups and introduce `cutoff models' to probe the fate of gauge symmetries under various such approximated renormalization group flows. For the Tensor Network Renormalization analysis, a new Gauss constraint preserving algorithm is introduced to improve numerical stability and aid physical interpretation. We also describe the fixed point structure and establish an equivalence of certain models.

Bianca Dittrich; Frank C. Eckert; Mercedes Martin-Benito

2011-09-22T23:59:59.000Z

189

M. SCIANNA ET AL. A MULTISCALE HYBRID APPROACH FOR VASCULOGENESIS AND RELATED POTENTIAL BLOCKING THERAPIES A MULTISCALE HYBRID APPROACH FOR VASCULOGENESIS AND RELATED POTENTIAL  

E-Print Network [OSTI]

LEVEL, AN EXTENDED LATTICE CPM, BASED ON A SYSTEM ENERGY REDUCTION, REPRODUCES CELL DYNAMICSM. SCIANNA ET AL. A MULTISCALE HYBRID APPROACH FOR VASCULOGENESIS AND RELATED POTENTIAL BLOCKING THERAPIES A MULTISCALE HYBRID APPROACH FOR VASCULOGENESIS AND RELATED POTENTIAL BLOCKING THERAPIES MARCO

Preziosi, Luigi

190

Augmented Lagrangian method for generalized TV-Stokes model  

E-Print Network [OSTI]

reducing stair-case effect. Keyword: TV-Stokes model, Augmented Lagrangian method, Image inpainting, Image and stair-case effect [6­10]. The authors [9] showed that the TV-L2 model never recover the same contrast-010 and MOE (Ministry of Education) Tier II project T207N2202. jyhahn@ntu.edu.sg CLWU@ntu.edu.sg §xctai@ntu

Soatto, Stefano

191

Limei Ran Research Associate, Center for Environmental Modeling for Policy Development  

E-Print Network [OSTI]

the Community Multiscale Air Quality Model (CMAQ) with the Environmental Policy Integrated Limei Ran Research Associate, Center for Environmental Modeling for Policy Development

McLaughlin, Richard M.

192

Bayesian methods for discontinuity detection in climate model predictions.  

SciTech Connect (OSTI)

Discontinuity detection is an important component in many fields: Image recognition, Digital signal processing, and Climate change research. Current methods shortcomings are: Restricted to one- or two-dimensional setting, Require uniformly spaced and/or dense input data, and Give deterministic answers without quantifying the uncertainty. Spectral methods for Uncertainty Quantification with global, smooth bases are challenged by discontinuities in model simulation results. Domain decomposition reduces the impact of nonlinearities and discontinuities. However, while gaining more smoothness in each subdomain, the current domain refinement methods require prohibitively many simulations. Therefore, detecting discontinuities up front and refining accordingly provides huge improvement to the current methodologies.

Safta, Cosmin; Debusschere, Bert J.; Najm, Habib N.; Sargsyan, Khachik

2010-06-01T23:59:59.000Z

193

Mathematical Models and Methods in Applied Sciences Vol. No. ( )  

E-Print Network [OSTI]

in Mathematical Models and Methods in Applied Sciences, Vol. 1, No. 6 (2001) pp. 933­949, #12;Some quantity = bacterial population (biomass) = amount of pollutant remaining. Note that we must include the distinction between `dormant' and `active' states for the biomass, say, by a (Boolean) indicator = {1 if `active'; 0

Seidman, Thomas I.

194

Summer Academy 2012 Advanced Stochastic Methods to Model Risk  

E-Print Network [OSTI]

Summer Academy 2012 Advanced Stochastic Methods to Model Risk PERSONAL INFORMATION Name Last name for participation in the summer academy I would like to book via the organizers an accommodation from 09 September presumably 452 . participation in the summer academy and a DAAD scholarship for participation If I am

Pfeifer, Holger

195

Interconnected hydro-thermal systems Models, methods, and applications  

E-Print Network [OSTI]

Interconnected hydro-thermal systems Models, methods, and applications Magnus Hindsberger Kgs. Lyngby 2003 IMM-PHD-2003-112 Interconnected hydro-thermalsystems #12;Technical University of Denmark 45882673 reception@imm.dtu.dk www.imm.dtu.dk IMM-PHD-2003-112 ISSN 0909-3192 #12;Interconnected hydro

196

Computational methods for several models of ice stream flow  

E-Print Network [OSTI]

on any grid Shallow ice approximation produces oscillatory solutions Nonlinear and linear solvers haveComputational methods for several models of ice stream flow Jed Brown Laboratory of Hydrology transition at ice stream margins Bed slope is discontinuous and of order 1. Taylor expansions no longer valid

Brown, Jed

197

A multiscale approximation algorithm for the cardinality constrained knapsack problem  

E-Print Network [OSTI]

I develop a multiscale approximation algorithm for the cardinality constrained knapsack problem. The algorithm consists of three steps: a rounding and reduction step where a hierarchical representation of the problem data ...

Krishnan, Bharath Kumar

2006-01-01T23:59:59.000Z

198

The linear and nonlinear rheology of multiscale complex fluids  

E-Print Network [OSTI]

The microstructures of many complex fluids are typically characterized by a broad distribution of internal length scales. Examples of such multiscale materials include physically and chemically cross-linked gels, emulsions, ...

Jaishankar, Aditya

2014-01-01T23:59:59.000Z

199

Integrated approaches to the optimal design of multiscale systems  

E-Print Network [OSTI]

This work is aimed at development of systematic approaches to the design of multiscale systems. Specifically four problems are addressed: environmental impact assessment (EIA) of new and retrofitted industrial processes, integration of process...

Lovelady, Eva Marie

2009-05-15T23:59:59.000Z

200

Adaptive two-regime method: Application to front propagation  

SciTech Connect (OSTI)

The Adaptive Two-Regime Method (ATRM) is developed for hybrid (multiscale) stochastic simulation of reaction-diffusion problems. It efficiently couples detailed Brownian dynamics simulations with coarser lattice-based models. The ATRM is a generalization of the previously developed Two-Regime Method [Flegg et al., J. R. Soc., Interface 9, 859 (2012)] to multiscale problems which require a dynamic selection of regions where detailed Brownian dynamics simulation is used. Typical applications include a front propagation or spatio-temporal oscillations. In this paper, the ATRM is used for an in-depth study of front propagation in a stochastic reaction-diffusion system which has its mean-field model given in terms of the Fisher equation [R. Fisher, Ann. Eugen. 7, 355 (1937)]. It exhibits a travelling reaction front which is sensitive to stochastic fluctuations at the leading edge of the wavefront. Previous studies into stochastic effects on the Fisher wave propagation speed have focused on lattice-based models, but there has been limited progress using off-lattice (Brownian dynamics) models, which suffer due to their high computational cost, particularly at the high molecular numbers that are necessary to approach the Fisher mean-field model. By modelling only the wavefront itself with the off-lattice model, it is shown that the ATRM leads to the same Fisher wave results as purely off-lattice models, but at a fraction of the computational cost. The error analysis of the ATRM is also presented for a morphogen gradient model.

Robinson, Martin, E-mail: martin.robinson@maths.ox.ac.uk; Erban, Radek, E-mail: erban@maths.ox.ac.uk [Mathematical Institute, University of Oxford, Andrew Wiles Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG (United Kingdom)] [Mathematical Institute, University of Oxford, Andrew Wiles Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG (United Kingdom); Flegg, Mark, E-mail: mark.flegg@monash.edu [School of Mathematical Sciences, Faculty of Science, Monash University Wellington Road, Clayton, Victoria 3800 (Australia)] [School of Mathematical Sciences, Faculty of Science, Monash University Wellington Road, Clayton, Victoria 3800 (Australia)

2014-03-28T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

When are microcircuits well-modeled by maximum entropy methods?  

E-Print Network [OSTI]

POSTER PRESENTATION Open Access When are microcircuits well-modeled by maximum entropy methods? Andrea K Barreiro1*, Eric T Shea-Brown1, Fred M Rieke2,3, Julijana Gjorgjieva4 From Nineteenth Annual Computational Neuroscience Meeting: CNS*2010 San... Antonio, TX, USA. 24-30 July 2010 Recent experiments in retina and cortex have demon- strated that pairwise maximum entropy (PME) methods can approximate observed spiking patterns to a high degree of accuracy [1,2]. In this paper we examine...

2010-07-20T23:59:59.000Z

202

Simulating Nationwide Pandemics: Applying the Multi-scale Epidemiologic Simulation and Analysis System to Human Infectious Diseases  

SciTech Connect (OSTI)

This study uses the Multi-scale Epidemiologic Simulation and Analysis (MESA) system developed for foreign animal diseases to assess consequences of nationwide human infectious disease outbreaks. A literature review identified the state of the art in both small-scale regional models and large-scale nationwide models and characterized key aspects of a nationwide epidemiological model. The MESA system offers computational advantages over existing epidemiological models and enables a broader array of stochastic analyses of model runs to be conducted because of those computational advantages. However, it has only been demonstrated on foreign animal diseases. This paper applied the MESA modeling methodology to human epidemiology. The methodology divided 2000 US Census data at the census tract level into school-bound children, work-bound workers, elderly, and stay at home individuals. The model simulated mixing among these groups by incorporating schools, workplaces, households, and long-distance travel via airports. A baseline scenario with fixed input parameters was run for a nationwide influenza outbreak using relatively simple social distancing countermeasures. Analysis from the baseline scenario showed one of three possible results: (1) the outbreak burned itself out before it had a chance to spread regionally, (2) the outbreak spread regionally and lasted a relatively long time, although constrained geography enabled it to eventually be contained without affecting a disproportionately large number of people, or (3) the outbreak spread through air travel and lasted a long time with unconstrained geography, becoming a nationwide pandemic. These results are consistent with empirical influenza outbreak data. The results showed that simply scaling up a regional small-scale model is unlikely to account for all the complex variables and their interactions involved in a nationwide outbreak. There are several limitations of the methodology that should be explored in future work including validating the model against reliable historical disease data, improving contact rates, spread methods, and disease parameters through discussions with epidemiological experts, and incorporating realistic behavioral assumptions.

Dombroski, M; Melius, C; Edmunds, T; Banks, L E; Bates, T; Wheeler, R

2008-09-24T23:59:59.000Z

203

Next Generation Multi-Scale Quantum Simulation Software for Strongly Correlated Materials  

SciTech Connect (OSTI)

The goal of this project was to develop a new formalism for the correlated electron problem, which we call, the Multi Scale Many Body formalism. This report will focus on the work done at the Louisiana State University (LSU) since the mid term report. The LSU group moved from the University of Cincinnati (UC) to LSU in the summer of 2008. In the last full year at UC, only half of the funds were received and it took nearly two years for the funds to be transferred from UC to LSU . This effectively shut down the research at LSU until the transfer was completed in 2011, there were also two no-cost extensions of the grant until August of this year. The grant ended for the other SciDAC partners at Davis and ORNL in 2011. Since the mid term report, the LSU group has published 19 papers [P1-P19] acknowledging this SciDAC, which are listed below. In addition, numerous invited talked acknowledged the SciDAC. Below, we will summarize the work at LSU since the mid-term report and mainly since funding resumed. The projects include the further development of multi-scale methods for correlated systems (1), the study of quantum criticality at finite doping in the Hubbard model (2), the description of a promising new method to study Anderson localization with a million-fold reduction of computational complexity!, the description of other projects (4), and (5) a workshop to close out the project that brought together exascale program developers (Stellar, MPI, OpenMP,...) with applications developers.

Jarrell, Mark

2014-11-18T23:59:59.000Z

204

Alternative wind power modeling methods using chronological and load duration curve production cost models  

SciTech Connect (OSTI)

As an intermittent resource, capturing the temporal variation in windpower is an important issue in the context of utility production cost modeling. Many of the production cost models use a method that creates a cumulative probability distribution that is outside the time domain. The purpose of this report is to examine two production cost models that represent the two major model types: chronological and load duration cure models. This report is part of the ongoing research undertaken by the Wind Technology Division of the National Renewable Energy Laboratory in utility modeling and wind system integration.

Milligan, M R

1996-04-01T23:59:59.000Z

205

Arctic sea ice modeling with the material-point method.  

SciTech Connect (OSTI)

Arctic sea ice plays an important role in global climate by reflecting solar radiation and insulating the ocean from the atmosphere. Due to feedback effects, the Arctic sea ice cover is changing rapidly. To accurately model this change, high-resolution calculations must incorporate: (1) annual cycle of growth and melt due to radiative forcing; (2) mechanical deformation due to surface winds, ocean currents and Coriolis forces; and (3) localized effects of leads and ridges. We have demonstrated a new mathematical algorithm for solving the sea ice governing equations using the material-point method with an elastic-decohesive constitutive model. An initial comparison with the LANL CICE code indicates that the ice edge is sharper using Materials-Point Method (MPM), but that many of the overall features are similar.

Peterson, Kara J.; Bochev, Pavel Blagoveston

2010-04-01T23:59:59.000Z

206

HyPEP FY06 Report: Models and Methods  

SciTech Connect (OSTI)

The Department of Energy envisions the next generation very high-temperature gas-cooled reactor (VHTR) as a single-purpose or dual-purpose facility that produces hydrogen and electricity. The Ministry of Science and Technology (MOST) of the Republic of Korea also selected VHTR for the Nuclear Hydrogen Development and Demonstration (NHDD) Project. This research project aims at developing a user-friendly program for evaluating and optimizing cycle efficiencies of producing hydrogen and electricity in a Very-High-Temperature Reactor (VHTR). Systems for producing electricity and hydrogen are complex and the calculations associated with optimizing these systems are intensive, involving a large number of operating parameter variations and many different system configurations. This research project will produce the HyPEP computer model, which is specifically designed to be an easy-to-use and fast running tool for evaluating nuclear hydrogen and electricity production facilities. The model accommodates flexible system layouts and its cost models will enable HyPEP to be well-suited for system optimization. Specific activities of this research are designed to develop the HyPEP model into a working tool, including (a) identifying major systems and components for modeling, (b) establishing system operating parameters and calculation scope, (c) establishing the overall calculation scheme, (d) developing component models, (e) developing cost and optimization models, and (f) verifying and validating the program. Once the HyPEP model is fully developed and validated, it will be used to execute calculations on candidate system configurations. FY-06 report includes a description of reference designs, methods used in this study, models and computational strategies developed for the first year effort. Results from computer codes such as HYSYS and GASS/PASS-H used by Idaho National Laboratory and Argonne National Laboratory, respectively will be benchmarked with HyPEP results in the following years.

DOE report

2006-09-01T23:59:59.000Z

207

Frequency ratio method for seismic modeling of Gamma Doradus stars  

E-Print Network [OSTI]

A method for obtaining asteroseismological information of a Gamma Doradus oscillating star showing at least three pulsation frequencies is presented. This method is based on a first-order asymptotic g-mode expression, in agreement with the internal structure of Gamma Doradus stars. The information obtained is twofold: 1) a possible identification of the radial order n and degree l of observed frequencies (assuming that these have the same l), and 2) an estimate of the integral of the buoyancy frequency (Brunt-Vaisala) weighted over the stellar radius along the radiative zone. The accuracy of the method as well as its theoretical consistency are also discussed for a typical Gamma Doradus stellar model. Finally, the frequency ratios method has been tested with observed frequencies of the Gamma Doradus star HD 12901. The number of representative models verifying the complete set of constraints (the location in the HR diagram, the Brunt-Vaisala frequency integral, the observed metallicity and frequencies and a re...

Moya, A; Amado, P J; Martin-Ruiz, S; Garrido, R

2004-01-01T23:59:59.000Z

208

Multi-scale coarse-graining of non-conservative interactions in molecular liquids  

SciTech Connect (OSTI)

A new bottom-up procedure for constructing non-conservative (dissipative and stochastic) interactions for dissipative particle dynamics (DPD) models is described and applied to perform hierarchical coarse-graining of a polar molecular liquid (nitromethane). The distant-dependent radial and shear frictions in functional-free form are derived consistently with a chosen form for conservative interactions by matching two-body force-velocity and three-body velocity-velocity correlations along the microscopic trajectories of the centroids of Voronoi cells (clusters), which represent the dissipative particles within the DPD description. The Voronoi tessellation is achieved by application of the K-means clustering algorithm at regular time intervals. Consistently with a notion of many-body DPD, the conservative interactions are determined through the multi-scale coarse-graining (MS-CG) method, which naturally implements a pairwise decomposition of the microscopic free energy. A hierarchy of MS-CG/DPD models starting with one molecule per Voronoi cell and up to 64 molecules per cell is derived. The radial contribution to the friction appears to be dominant for all models. As the Voronoi cell sizes increase, the dissipative forces rapidly become confined to the first coordination shell. For Voronoi cells of two and more molecules the time dependence of the velocity autocorrelation function becomes monotonic and well reproduced by the respective MS-CG/DPD models. A comparative analysis of force and velocity correlations in the atomistic and CG ensembles indicates Markovian behavior with as low as two molecules per dissipative particle. The models with one and two molecules per Voronoi cell yield transport properties (diffusion and shear viscosity) that are in good agreement with the atomistic data. The coarser models produce slower dynamics that can be appreciably attributed to unaccounted dissipation introduced by regular Voronoi re-partitioning as well as by larger numerical errors in mapping out the dissipative forces. The framework presented herein can be used to develop computational models of real liquids which are capable of bridging the atomistic and mesoscopic scales.

Izvekov, Sergei, E-mail: sergiy.izvyekov.civ@mail.mil; Rice, Betsy M. [U.S. Army Research Laboratory, Aberdeen Proving Ground, Maryland 21005 (United States)] [U.S. Army Research Laboratory, Aberdeen Proving Ground, Maryland 21005 (United States)

2014-03-14T23:59:59.000Z

209

Multi-scale Stroke-based Rendering by Evolutionary Algorithm Hyung W. Kang, Uday K. Chakraborty, Charles K. Chui, Wenjie He  

E-Print Network [OSTI]

Multi-scale Stroke-based Rendering by Evolutionary Algorithm Hyung W. Kang, Uday K. Chakraborty-scale stroke-based non-photorealistic rendering. The proposed method produces better results than previously: Non-photorealistic rendering, Stroke-based rendering, Computer graphics, Evolutionary algorithm 1

He, Wenjie

210

Compositional modeling of threephase flow with gravity using higherorder finite element methods  

E-Print Network [OSTI]

Compositional modeling of threephase flow with gravity using higherorder finite element methods using higherorder finite element methods. Gravity poses complications in modeling multiphase processes flow with gravity using higherorder finite element methods, Water Resour. Res., 47, W05511, doi:10

Firoozabadi, Abbas

211

Methods for Developing Emissions Scenarios for Integrated Assessment Models  

SciTech Connect (OSTI)

The overall objective of this research was to contribute data and methods to support the future development of new emissions scenarios for integrated assessment of climate change. Specifically, this research had two main objectives: 1. Use historical data on economic growth and energy efficiency changes, and develop probability density functions (PDFs) for the appropriate parameters for two or three commonly used integrated assessment models. 2. Using the parameter distributions developed through the first task and previous work, we will develop methods of designing multi-gas emission scenarios that usefully span the joint uncertainty space in a small number of scenarios. Results on the autonomous energy efficiency improvement (AEEI) parameter are summarized, an uncertainty analysis of elasticities of substitution is described, and the probabilistic emissions scenario approach is presented.

Prinn, Ronald [MIT; Webster, Mort [MIT

2007-08-20T23:59:59.000Z

212

System and methods for predicting transmembrane domains in membrane proteins and mining the genome for recognizing G-protein coupled receptors  

DOE Patents [OSTI]

The invention provides computer-implemented methods and apparatus implementing a hierarchical protocol using multiscale molecular dynamics and molecular modeling methods to predict the presence of transmembrane regions in proteins, such as G-Protein Coupled Receptors (GPCR), and protein structural models generated according to the protocol. The protocol features a coarse grain sampling method, such as hydrophobicity analysis, to provide a fast and accurate procedure for predicting transmembrane regions. Methods and apparatus of the invention are useful to screen protein or polynucleotide databases for encoded proteins with transmembrane regions, such as GPCRs.

Trabanino, Rene J; Vaidehi, Nagarajan; Hall, Spencer E; Goddard, William A; Floriano, Wely

2013-02-05T23:59:59.000Z

213

WIDE-FIELD ASTRONOMICAL MULTISCALE CAMERAS  

SciTech Connect (OSTI)

In order to produce sufficiently low aberrations with a large aperture, telescopes have a limited field of view. Because of this narrow field, large areas of the sky at a given time are unobserved. We propose several telescopes based on monocentric reflective, catadioptric, and refractive objectives that may be scaled to wide fields of view and achieve 1.''1 resolution, which in most locations is the practical seeing limit of the atmosphere. The reflective and Schmidt catadioptric objectives have relatively simple configurations and enable large fields to be captured at the expense of the obscuration of the mirror by secondary optics, a defect that may be managed by image plane design. The refractive telescope design does not have an obscuration but the objective has substantial bulk. The refractive design is a 38 gigapixel camera which consists of a single monocentric objective and 4272 microcameras. Monocentric multiscale telescopes, with their wide fields of view, may observe phenomena that might otherwise be unnoticed, such as supernovae, glint from orbital space debris, and near-earth objects.

Marks, Daniel L.; Brady, David J., E-mail: dbrady@ee.duke.edu [Department of Electrical and Computer Engineering and Fitzpatrick Institute for Photonics, Box 90291, Duke University, Durham, NC 27708 (United States)

2013-05-15T23:59:59.000Z

214

Assessment of Molecular Modeling & Simulation  

SciTech Connect (OSTI)

This report reviews the development and applications of molecular and materials modeling in Europe and Japan in comparison to those in the United States. Topics covered include computational quantum chemistry, molecular simulations by molecular dynamics and Monte Carlo methods, mesoscale modeling of material domains, molecular-structure/macroscale property correlations like QSARs and QSPRs, and related information technologies like informatics and special-purpose molecular-modeling computers. The panel's findings include the following: The United States leads this field in many scientific areas. However, Canada has particular strengths in DFT methods and homogeneous catalysis; Europe in heterogeneous catalysis, mesoscale, and materials modeling; and Japan in materials modeling and special-purpose computing. Major government-industry initiatives are underway in Europe and Japan, notably in multi-scale materials modeling and in development of chemistry-capable ab-initio molecular dynamics codes.

None

2002-01-03T23:59:59.000Z

215

Qualitative Comparison of Multiscale Skin Tumor Segmentation Methods  

E-Print Network [OSTI]

Davila" Univ. of Medicine and Pharmacy Bucharest, Romania Alexandru Telea Univ. of Groningen, Romania Caius Solovan "Victor Babes" Univ. of Medicine and Pharmacy Timisoara, Romania Razvan Voineacu Institute for World Economy Bucharest, Romania Aim Comparison Results We acquired over 100 images of a wide

Telea, Alexandru C.

216

Multiscale numerical methods for some types of parabolic equations  

E-Print Network [OSTI]

parabolic equations in strongly channelized media. We concentrate on showing that the solution depends on the steady state solution smoothly. As for the first problem, we obtain quantitive estimates for the convergence of the correctors and some parts...

Nam, Dukjin

2009-05-15T23:59:59.000Z

217

Forest understory soil temperatures and heat flux calculated using a Fourier model and scaled using a digital camera  

E-Print Network [OSTI]

with an infrared thermometer along an 11 m transect, a sun?Multiscale sensing Infrared thermometer Remote sensing Imagefacing infrared thermometer (Model 4000.3ZL, Ever- est

Graham, Eric; Lam, Yeung; Yuen, Eric

2010-01-01T23:59:59.000Z

218

Graphical models and variational methods Zoubin Ghahramani and Matthew J. Beal  

E-Print Network [OSTI]

Graphical models and variational methods Zoubin Ghahramani and Matthew J. Beal Gatsby Computational://www.gatsby.ucl.ac.uk July, 2000 Ghahramani, Z. and Beal, M.J. (2000) Graphical models and variational methods. To appear

Ghahramani, Zoubin

219

Multi-Scale Initial Conditions For Cosmological Simulations  

SciTech Connect (OSTI)

We discuss a new algorithm to generate multi-scale initial conditions with multiple levels of refinements for cosmological 'zoom-in' simulations. The method uses an adaptive convolution of Gaussian white noise with a real-space transfer function kernel together with an adaptive multi-grid Poisson solver to generate displacements and velocities following first- (1LPT) or second-order Lagrangian perturbation theory (2LPT). The new algorithm achieves rms relative errors of the order of 10{sup -4} for displacements and velocities in the refinement region and thus improves in terms of errors by about two orders of magnitude over previous approaches. In addition, errors are localized at coarse-fine boundaries and do not suffer from Fourier-space-induced interference ringing. An optional hybrid multi-grid and Fast Fourier Transform (FFT) based scheme is introduced which has identical Fourier-space behaviour as traditional approaches. Using a suite of re-simulations of a galaxy cluster halo our real-space-based approach is found to reproduce correlation functions, density profiles, key halo properties and subhalo abundances with per cent level accuracy. Finally, we generalize our approach for two-component baryon and dark-matter simulations and demonstrate that the power spectrum evolution is in excellent agreement with linear perturbation theory. For initial baryon density fields, it is suggested to use the local Lagrangian approximation in order to generate a density field for mesh-based codes that is consistent with the Lagrangian perturbation theory instead of the current practice of using the Eulerian linearly scaled densities.

Hahn, Oliver; /KIPAC, Menlo Park; Abel, Tom; /KIPAC, Menlo Park /ZAH, Heidelberg /HITS, Heidelberg

2011-11-04T23:59:59.000Z

220

Avalanches through windows: Multiscale visualization in magnetic thin films  

E-Print Network [OSTI]

Avalanches through windows: Multiscale visualization in magnetic thin films Alessandro Magni, Cornell University, Ithaca, NY 14853-2501 Abstract--The dynamics of domain walls motion in thin films dynamics, but are strongly dependent on the size of the windows chosen. Here we investigate how to properly

Sethna, James P.

Note: This page contains sample records for the topic "method multiscale modeling" 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

Uniformly Accurate Diffusive Relaxation Schemes for Multiscale Transport Equations  

E-Print Network [OSTI]

, radiative transfer, and transport equations for waves in random media, have a diffusive scaling that leads #12; 1. Introduction Many transport equations, such as the neutron transport [CZ], radiative transferUniformly Accurate Diffusive Relaxation Schemes for Multiscale Transport Equations Shi JIN y

222

Dynamic Multiscale Boundary Conditions for 4D CT Images of Healthy and Emphysematous Rat  

SciTech Connect (OSTI)

Changes in the shape of the lung during breathing determine the movement of airways and alveoli, and thus impact airflow dynamics. Modeling airflow dynamics in health and disease is a key goal for predictive multiscale models of respiration. Past efforts to model changes in lung shape during breathing have measured shape at multiple breath-holds. However, breath-holds do not capture hysteretic differences between inspiration and expiration resulting from the additional energy required for inspiration. Alternatively, imaging dynamically – without breath-holds – allows measurement of hysteretic differences. In this study, we acquire multiple micro-CT images per breath (4DCT) in live rats, and from these images we develop, for the first time, dynamic volume maps. These maps show changes in local volume across the entire lung throughout the breathing cycle and accurately predict the global pressure-volume (PV) hysteresis.

Jacob, Rick E.; Carson, James P.; Thomas, Mathew; Einstein, Daniel R.

2013-06-14T23:59:59.000Z

223

State-space models and methods for MIMO communication  

E-Print Network [OSTI]

Estimation with State-Space Models . . . . . . . . . . . 2.12.2 State-Space Models for MIMO WirelessEqualization via State- Space Deconvolution . . . . . . 4.1

Zhang, Chengjin

2007-01-01T23:59:59.000Z

224

A Perspective on Coupled Multiscale Simulation and Validation in Nuclear Materials  

SciTech Connect (OSTI)

The field of nuclear materials encompasses numerous opportunities to address and ultimately solve longstanding industrial problems by improving the fundamental understanding of materials through the integration of experiments with multiscale modeling and high-performance simulation. A particularly noteworthy example is an ongoing study of axial power distortions in a nuclear reactor induced by corrosion deposits, known as CRUD (Chalk River unidentified deposits). We describe how progress is being made toward achieving scientific advances and technological solutions on two fronts. Specifically, the study of thermal conductivity of CRUD phases has augmented missing data as well as revealed new mechanisms. Additionally, the development of a multiscale simulation framework shows potential for the validation of a new capability to predict the power distribution of a reactor, in effect direct evidence of technological impact. The material- and system-level challenges identified in the study of CRUD are similar to other well-known vexing problems in nuclear materials, such as irradiation accelerated corrosion, stress corrosion cracking, and void swelling; they all involve connecting materials science fundamentals at the atomistic- and mesoscales to technology challenges at the macroscale.

M. P. Short; D. Gaston; C. R. Stanek; S. Yip

2014-01-01T23:59:59.000Z

225

Neural node network and model, and method of teaching same  

DOE Patents [OSTI]

The present invention is a fully connected feed forward network that includes at least one hidden layer 16. The hidden layer 16 includes nodes 20 in which the output of the node is fed back to that node as an input with a unit delay produced by a delay device 24 occurring in the feedback path 22 (local feedback). Each node within each layer also receives a delayed output (crosstalk) produced by a delay unit 36 from all the other nodes within the same layer 16. The node performs a transfer function operation based on the inputs from the previous layer and the delayed outputs. The network can be implemented as analog or digital or within a general purpose processor. Two teaching methods can be used: (1) back propagation of weight calculation that includes the local feedback and the crosstalk or (2) more preferably a feed forward gradient decent which immediately follows the output computations and which also includes the local feedback and the crosstalk. Subsequent to the gradient propagation, the weights can be normalized, thereby preventing convergence to a local optimum. Education of the network can be incremental both on and off-line. An educated network is suitable for modeling and controlling dynamic nonlinear systems and time series systems and predicting the outputs as well as hidden states and parameters. The educated network can also be further educated during on-line processing.

Parlos, Alexander G. (College Station, TX); Atiya, Amir F. (College Station, TX); Fernandez, Benito (Austin, TX); Tsai, Wei K. (Irvine, CA); Chong, Kil T. (College Station, TX)

1995-01-01T23:59:59.000Z

226

Neural node network and model, and method of teaching same  

DOE Patents [OSTI]

The present invention is a fully connected feed forward network that includes at least one hidden layer. The hidden layer includes nodes in which the output of the node is fed back to that node as an input with a unit delay produced by a delay device occurring in the feedback path (local feedback). Each node within each layer also receives a delayed output (crosstalk) produced by a delay unit from all the other nodes within the same layer. The node performs a transfer function operation based on the inputs from the previous layer and the delayed outputs. The network can be implemented as analog or digital or within a general purpose processor. Two teaching methods can be used: (1) back propagation of weight calculation that includes the local feedback and the crosstalk or (2) more preferably a feed forward gradient decent which immediately follows the output computations and which also includes the local feedback and the crosstalk. Subsequent to the gradient propagation, the weights can be normalized, thereby preventing convergence to a local optimum. Education of the network can be incremental both on and off-line. An educated network is suitable for modeling and controlling dynamic nonlinear systems and time series systems and predicting the outputs as well as hidden states and parameters. The educated network can also be further educated during on-line processing. 21 figs.

Parlos, A.G.; Atiya, A.F.; Fernandez, B.; Tsai, W.K.; Chong, K.T.

1995-12-26T23:59:59.000Z

227

Contributions to Meta-Modeling Tools and Methods  

E-Print Network [OSTI]

;2 Outline Product Design Environments Meta-Modeling Modelica Meta-Model Invasive Composition of Modelica Model-driven Product Design using Modelica Meta-Programming Debugging of Natural Semantics-driven product design environments Modeling and simulation Modelica Framework Objective Efficient development

Zhao, Yuxiao

228

Error Control Based Model Reduction for Parameter Optimization of Elliptic  

E-Print Network [OSTI]

of technical devices that rely on multiscale processes, such as fuel cells or batteries. As the solutionError Control Based Model Reduction for Parameter Optimization of Elliptic Homogenization Problems optimization of elliptic multiscale problems with macroscopic optimization functionals and microscopic material

229

Multi-scale analysis and simulation of powder blending in pharmaceutical manufacturing  

E-Print Network [OSTI]

A Multi-Scale Analysis methodology was developed and carried out for gaining fundamental understanding of the pharmaceutical powder blending process. Through experiment, analysis and computer simulations, microscopic ...

Ngai, Samuel S. H

2005-01-01T23:59:59.000Z

230

E-Print Network 3.0 - automatic multiscale enhancement Sample...  

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

University Collection: Materials Science 4 POTENTIAL FIELD WAVELETS AS A TOOL IN EXPLORATION Summary: of wavelet multiscale maxima (or edges) allows the automatic production of...

231

Multiscale Toxicology- Building the Next Generation Tools for Toxicology  

SciTech Connect (OSTI)

A Cooperative Research and Development Agreement (CRADA) was established between Battelle Memorial Institute (BMI), Pacific Northwest National Laboratory (PNNL), Oak Ridge National Laboratory (ORNL), Brookhaven National Laboratory (BNL), Lawrence Livermore National Laboratory (LLNL) with the goal of combining the analytical and synthetic strengths of the National Laboratories with BMI?s expertise in basic and translational medical research to develop a collaborative pipeline and suite of high throughput and imaging technologies that could be used to provide a more comprehensive understanding of material and drug toxicology in humans. The Multi-Scale Toxicity Initiative (MSTI), consisting of the team members above, was established to coordinate cellular scale, high-throughput in vitro testing, computational modeling and whole animal in vivo toxicology studies between MSTI team members. Development of a common, well-characterized set of materials for testing was identified as a crucial need for the initiative. Two research tracks were established by BMI during the course of the CRADA. The first research track focused on the development of tools and techniques for understanding the toxicity of nanomaterials, specifically inorganic nanoparticles (NPs). ORNL?s work focused primarily on the synthesis, functionalization and characterization of a common set of NPs for dissemination to the participating laboratories. These particles were synthesized to retain the same surface characteristics and size, but to allow visualization using the variety of imaging technologies present across the team. Characterization included the quantitative analysis of physical and chemical properties of the materials as well as the preliminary assessment of NP toxicity using commercially available toxicity screens and emerging optical imaging strategies. Additional efforts examined the development of high-throughput microfluidic and imaging assays for measuring NP uptake, localization, and toxicity in vitro. The second research track within the MSTI CRADA focused on the development of ex vivo animal models for examining druginduced cardiotoxicity. ORNL's role in the second track was limited initially, but was later expanded to include the development of microfluidic platforms that might facilitate the translation of Cardiac 'Microwire' technologies developed at the University of Toronto into a functional platform for drug screening and predictive assessment of cardiotoxicity via highthroughput measurements of contractility. This work was coordinated by BMI with the Centre for the Commercialization of Regenerative Medicine (CCRM) and the University of Toronto (U Toronto). This partnership was expanded and culminated in the submission of proposal to Work for Others (WFO) agencies to explore the development of a broader set of microphysiological systems, a so call human-on-a-chip, that could be used for toxicity screening and the evaluation of bio-threat countermeasures.

Retterer, S. T. [ORNL] [ORNL; Holsapple, M. P. [Battelle Memorial Institute] [Battelle Memorial Institute

2013-10-31T23:59:59.000Z

232

On fast trust region methods for quadratic models with linear ...  

E-Print Network [OSTI]

employs conjugate gradients with termination at the trust region boundary. In particular, we ... An extension to the conjugate gradient method for searching round.

2014-08-28T23:59:59.000Z

233

A STABILIZED MODEL AND AN EFFICIENT SOLUTION METHOD ...  

E-Print Network [OSTI]

1. Introduction. Given a fixed mix of electric power plants (nuclear, thermal, hydroelectric and possibly peak ... the stabilized method on numerical simulations. 2.

2011-01-28T23:59:59.000Z

234

Radiation Damage in Nuclear Fuel for Advanced Burner Reactors: Modeling and Experimental Validation  

SciTech Connect (OSTI)

The consortium has completed its existence and we are here highlighting work and accomplishments. As outlined in the proposal, the objective of the work was to advance the theoretical understanding of advanced nuclear fuel materials (oxides) toward a comprehensive modeling strategy that incorporates the different relevant scales involved in radiation damage in oxide fuels. Approaching this we set out to investigate and develop a set of directions: 1) Fission fragment and ion trajectory studies through advanced molecular dynamics methods that allow for statistical multi-scale simulations. This work also includes an investigation of appropriate interatomic force fields useful for the energetic multi-scale phenomena of high energy collisions; 2) Studies of defect and gas bubble formation through electronic structure and Monte Carlo simulations; and 3) an experimental component for the characterization of materials such that comparisons can be obtained between theory and experiment.

Jensen, Niels Gronbech; Asta, Mark; Ozolins, Nigel Browning'Vidvuds; de Walle, Axel van; Wolverton, Christopher

2011-12-29T23:59:59.000Z

235

Space Mapping: Models, Sensitivities, and Trust-Regions Methods 1 ...  

E-Print Network [OSTI]

We consider also a di erent perspective of space mapping and apply it, ... built by composition of the space mapping and the coarse model is a regular function.

236

AUTOMATIC PARALLELIZATION OF OBJECT ORIENTED MODELS ACROSS METHOD AND  

E-Print Network [OSTI]

was done on the system only. Keywords: Modelica, automatic parallelization. Presenting Author's biography and Modelica Modelica is a rather new language for equation-based object-oriented mathematical modeling which object- oriented modeling languages. Modelica is intended to become a de facto standard. It allows

Zhao, Yuxiao

237

Maximization of permanent trapping of CO{sub 2} and co-contaminants in the highest-porosity formations of the Rock Springs Uplift (Southwest Wyoming): experimentation and multi-scale modeling  

SciTech Connect (OSTI)

Under this project, a multidisciplinary team of researchers at the University of Wyoming combined state-of-the-art experimental studies, numerical pore- and reservoir-scale modeling, and high performance computing to investigate trapping mechanisms relevant to geologic storage of mixed scCO{sub 2} in deep saline aquifers. The research included investigations in three fundamental areas: (i) the experimental determination of two-­?phase flow relative permeability functions, relative permeability hysteresis, and residual trapping under reservoir conditions for mixed scCO{sub 2}-­?brine systems; (ii) improved understanding of permanent trapping mechanisms; (iii) scientifically correct, fine grid numerical simulations of CO{sub 2} storage in deep saline aquifers taking into account the underlying rock heterogeneity. The specific activities included: (1) Measurement of reservoir-­?conditions drainage and imbibition relative permeabilities, irreducible brine and residual mixed scCO{sub 2} saturations, and relative permeability scanning curves (hysteresis) in rock samples from RSU; (2) Characterization of wettability through measurements of contact angles and interfacial tensions under reservoir conditions; (3) Development of physically-­?based dynamic core-­?scale pore network model; (4) Development of new, improved high-­? performance modules for the UW-­?team simulator to provide new capabilities to the existing model to include hysteresis in the relative permeability functions, geomechanical deformation and an equilibrium calculation (Both pore-­? and core-­?scale models were rigorously validated against well-­?characterized core-­? flooding experiments); and (5) An analysis of long term permanent trapping of mixed scCO{sub 2} through high-­?resolution numerical experiments and analytical solutions. The analysis takes into account formation heterogeneity, capillary trapping, and relative permeability hysteresis.

Piri, Mohammad

2014-03-31T23:59:59.000Z

238

Investigation of Multiscale and Multiphase Flow, Transport and Reaction in Heavy Oil Recovery Processes  

SciTech Connect (OSTI)

This project is an investigation of various multi-phase and multiscale transport and reaction processes associated with heavy oil recovery. The thrust areas of the project include the following: Internal drives, vapor-liquid flows, combustion and reaction processes, fluid displacements and the effect of instabilities and heterogeneities and the flow of fluids with yield stress. These find respective applications in foamy oils, the evolution of dissolved gas, internal steam drives, the mechanics of concurrent and countercurrent vapor-liquid flows, associated with thermal methods and steam injection, such as SAGD, the in-situ combustion, the upscaling of displacements in heterogeneous media and the flow of foams, Bingham plastics and heavy oils in porous media and the development of wormholes during cold production.

Yortsos, Yanis C.

2001-08-07T23:59:59.000Z

239

Investigation of Multiscale and Multiphase Flow, Transport and Reaction in Heavy Oil Recovery Processes  

SciTech Connect (OSTI)

This report is an investigation of various multi-phase and multiscale transport and reaction processes associated with heavy oil recovery. The thrust areas of the project include the following: Internal drives, vapor-liquid flows, combustion and reaction processes, fluid displacements and the effect of instabilities and heterogeneities and the flow of fluids with yield stress. These find respective applications in foamy oils, the evolution of dissolved gas, internal steam drives, the mechanics of concurrent and countercurrent vapor-liquid flows, associated with thermal methods and steam injection, such as SAGD, the in-situ combustion, the upscaling of displacements in heterogeneous media and the flow of foams, Bingham plastics and heavy oils in porous media and the development of wormholes during cold production.

Yortsos, Y.C.

2001-05-29T23:59:59.000Z

240

Accelerated Iterative Method for Solving Steady Solutions of Linearized Atmospheric Models  

E-Print Network [OSTI]

Accelerated Iterative Method for Solving Steady Solutions of Linearized Atmospheric Models Masahiro approach, referred to as the accelerated iterative method (AIM), is developed for solving steady state, respectively. For ensuring the accelerated asymptotic convergence of iterative procedure

Watanabe, Masahiro

Note: This page contains sample records for the topic "method multiscale modeling" 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

M. Toubin, C. Dumont, E. P. Verrechia, O. Lalligant, A. Diou, F. Truchetet, and M. A. Abidi, "A Multi-scale Analysis of shell growth increments using wavelet transform," Computers & Geosciences, Journal of the International Association for Mathematical Ge  

E-Print Network [OSTI]

Multi-scale Analysis of shell growth increments using wavelet transform," Computers & Geosciences been tried (Dolman, 1975) using a Fourier transform. This method, based on power spectra analysis scales of resolution. As an example, the wavelet transform is used here to rank shell growth increments

Abidi, Mongi A.

242

Convergence of trust-region methods based on probabilistic models  

E-Print Network [OSTI]

the list of applications—including molecular geometry optimization, circuit design, ... A complex mechanism of sample set maintenance is ... shown that one can build such models, meeting a Taylor type accuracy with high probability,.

2013-10-24T23:59:59.000Z

243

analytical modeling method: Topics by E-print Network  

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

2006-11-21 396 Coupled thermodynamic-dynamic semi-analytical model of Free Piston Stirling engines CERN Preprints Summary: The study of free piston Stirling engine (FPSE)...

244

MREG V1.1 : a multi-scale image registration algorithm for SAR applications.  

SciTech Connect (OSTI)

MREG V1.1 is the sixth generation SAR image registration algorithm developed by the Signal Processing&Technology Department for Synthetic Aperture Radar applications. Like its predecessor algorithm REGI, it employs a powerful iterative multi-scale paradigm to achieve the competing goals of sub-pixel registration accuracy and the ability to handle large initial offsets. Since it is not model based, it allows for high fidelity tracking of spatially varying terrain-induced misregistration. Since it does not rely on image domain phase, it is equally adept at coherent and noncoherent image registration. This document provides a brief history of the registration processors developed by Dept. 5962 leading up to MREG V1.1, a full description of the signal processing steps involved in the algorithm, and a user's manual with application specific recommendations for CCD, TwoColor MultiView, and SAR stereoscopy.

Eichel, Paul H.

2013-08-01T23:59:59.000Z

245

3D Downtown Phoenix Modeling This project is to develop the efficient and effective method for  

E-Print Network [OSTI]

3D Downtown Phoenix Modeling ABSTRACT This project is to develop the efficient and effective method for creating 3D city models that will be used with GIS (Geographical Information Systems) data in VR (Virtual Reality) environment. Here introduces the modeling process to create 3D city model from aerial photos

Hall, Sharon J.

246

Three-Dimensional Lithium-Ion Battery Model (Presentation)  

SciTech Connect (OSTI)

Nonuniform battery physics can cause unexpected performance and life degradations in lithium-ion batteries; a three-dimensional cell performance model was developed by integrating an electrode-scale submodel using a multiscale modeling scheme.

Kim, G. H.; Smith, K.

2008-05-01T23:59:59.000Z

247

Optimal Multi-scale Capacity Planning under Hourly Varying Electricity Prices  

E-Print Network [OSTI]

1 Optimal Multi-scale Capacity Planning under Hourly Varying Electricity Prices Sumit Mitra Ignacio;2 Motivation of this work · Deregulation of the electricity markets caused electricity prices to be highly? (retrofit) · Challenge: Multi-scale nature of the problem! Hourly varying electricity prices vs. 10-15 years

Grossmann, Ignacio E.

248

MULTI-SCALE ANALYSIS OF MULTIPARAMETER GEOPHYSICAL AND GEOCHEMICAL DATA FROM  

E-Print Network [OSTI]

MULTI-SCALE ANALYSIS OF MULTIPARAMETER GEOPHYSICAL AND GEOCHEMICAL DATA FROM ACTIVE VOLCANIC Name: MAURI Guillaume Degree: PhD of Science Title of Thesis: Multi-scale analysis of multiparameter geophysical and geochemical data from active volcanic systems Examining Committee: Chair: Dr John Clague

Williams-Jones, Glyn

249

Stability of Nonlinear Subdivision and Multiscale Transforms S. Harizanov, P. Oswald  

E-Print Network [OSTI]

(median interpolating transform, power-p schemes, etc.). Although the investigation concentrates-investigated in the linear case when the components of the multiscale transform are linear, sparse maps. In this paper, weStability of Nonlinear Subdivision and Multiscale Transforms S. Harizanov, P. Oswald Jacobs

Oswald. Peter

250

Numerical Zoom for Multiscale Problems with an Application to Nuclear Waste Disposal  

E-Print Network [OSTI]

Numerical Zoom for Multiscale Problems with an Application to Nuclear Waste Disposal Jean of a nuclear waste repository site. Key words: Multiscale, Finite Element, Domain Decomposition, Chimera, Numerical Zoom, Nuclear Waste. PACS: 02.30.Jr, 47.11.Fg, 28.41.Kw, 47.55.P- 1 Introduction The present paper

251

MULTISCALE DATABASES TO SUPPORT VISUALISATION ON MOBILE DEVICES M. Hampe a,  

E-Print Network [OSTI]

devices like PDA's (Personal Digital Assistants) or Smartphones. With the increasing numberMULTISCALE DATABASES TO SUPPORT VISUALISATION ON MOBILE DEVICES M. Hampe a, *, M. Sester a , L display of mobile devices multiscale maps are created. The scale will decrease continuously starting

Harrie, Lars

252

Radiation transport modeling using extended quadrature method of moments  

SciTech Connect (OSTI)

The radiative transfer equation describes the propagation of radiation through a material medium. While it provides a highly accurate description of the radiation field, the large phase space on which the equation is defined makes it numerically challenging. As a consequence, significant effort has gone into the development of accurate approximation methods. Recently, an extended quadrature method of moments (EQMOM) has been developed to solve univariate population balance equations, which also have a large phase space and thus face similar computational challenges. The distinct advantage of the EQMOM approach over other moment methods is that it generates moment equations that are consistent with a positive phase space density and has a moment inversion algorithm that is fast and efficient. The goal of the current paper is to present the EQMOM method in the context of radiation transport, to discuss advantages and disadvantages, and to demonstrate its performance on a set of standard one-dimensional benchmark problems that encompass optically thin, thick, and transition regimes. Special attention is given in the implementation to the issue of realizability—that is, consistency with a positive phase space density. Numerical results in one dimension are promising and lay the foundation for extending the same framework to multiple dimensions.

Vikas, V., E-mail: vvikas@iastate.edu [Department of Aerospace Engineering, 2271 Howe Hall, Iowa State University, Ames, IA 50011 (United States); Hauck, C.D., E-mail: hauckc@ornl.gov [Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Wang, Z.J., E-mail: zjw@ku.edu [Department of Aerospace Engineering, 2120 Learned Hall, University of Kansas, Lawrence, KS 66045 (United States); Fox, R.O., E-mail: rofox@iastate.edu [Department of Chemical and Biological Engineering, 2114 Sweeney Hall, Iowa State University, Ames, IA 50011 (United States)

2013-08-01T23:59:59.000Z

253

A multiscale preconditioner for stochastic mortar mixed finite elements  

E-Print Network [OSTI]

physical models in different subdomains. The mortar finite element method is a generalization is the stochastic collocation method [4,40,39]. It combines a finite element discretiza- tion in physical space the approximation properties of the stochastic finite element method [5,37], making it more efficient than MCS

Yotov, Ivan

254

An Empirical Comparison of Field Defect Modeling Methods  

E-Print Network [OSTI]

Management, Measurement, Reliability, Experimentation, Defect modeling, empirical research, COTS, maintenance of Computer Science Carnegie Mellon University Pittsburgh PA, 15213 *Center for Software Engineering IBM T.J. Watson Research Center Hawthorne, NY 10532 This research was supported by the National Science Foundation

255

Synthetic Spectrum Methods for Three-Dimensional Supernova Models  

E-Print Network [OSTI]

Current observations stimulate the production of fully three-dimensional explosion models, which in turn motivates three-dimensional spectrum synthesis for supernova atmospheres. We briefly discuss techniques adapted to address the latter problem, and consider some fundamentals of line formation in supernovae without recourse to spherical symmetry. Direct and detailed extensions of the technique are discussed, and future work is outlined.

R. C. Thomas

2003-10-21T23:59:59.000Z

256

An energy-preserving muscle tissue model: formulation and compatible discretizations  

E-Print Network [OSTI]

An energy-preserving muscle tissue model: formulation and compatible discretizations D. Chapelle ­ phenomena associated with these energy considerations. Keywords: muscle tissue modeling; myocardium; multiscale; energy balance; time and space discretizations 1 Introduction The modeling of the active

Paris-Sud XI, Université de

257

Numerical Methods for the Bogoliubov-Tolmachev-Shirkov model in superconductivity theory  

E-Print Network [OSTI]

In the work, the numerical methods are designed for the Bogoliubov-Tolmachev-Shirkov model in superconductivity theory. The numerical methods are novel and effective to determine the critical transition temperature and approximate to the energy gap function of the above model. Finally, a numerical example confirming the theoretical results is presented.

Zhihao Ge; Ruihua Li

2014-12-25T23:59:59.000Z

258

Numerical Methods for the Bogoliubov-Tolmachev-Shirkov model in superconductivity theory  

E-Print Network [OSTI]

In the work, the numerical methods are designed for the Bogoliubov-Tolmachev-Shirkov model in superconductivity theory. The numerical methods are novel and effective to determine the critical transition temperature and approximate to the energy gap function of the above model. Finally, a numerical example confirming the theoretical results is presented.

Zhihao Ge; Ruihua Li

2015-03-08T23:59:59.000Z

259

Method of modeling transmissions for real-time simulation  

DOE Patents [OSTI]

A transmission modeling system includes an in-gear module that determines an in-gear acceleration when a vehicle is in gear. A shift module determines a shift acceleration based on a clutch torque when the vehicle is shifting between gears. A shaft acceleration determination module determines a shaft acceleration based on at least one of the in-gear acceleration and the shift acceleration.

Hebbale, Kumaraswamy V.

2012-09-25T23:59:59.000Z

260

Methods and apparatus for measurement of a dimensional characteristic and methods of predictive modeling related thereto  

DOE Patents [OSTI]

A method of optically determining a change in magnitude of at least one dimensional characteristic of a sample in response to a selected chamber environment. A magnitude of at least one dimension of the at least one sample may be optically determined subsequent to altering the at least one environmental condition within the chamber. A maximum change in dimension of the at least one sample may be predicted. A dimensional measurement apparatus for indicating a change in at least one dimension of at least one sample. The dimensional measurement apparatus may include a housing with a chamber configured for accommodating pressure changes and an optical perception device for measuring a dimension of at least one sample disposed in the chamber. Methods of simulating injection of a gas into a subterranean formation, injecting gas into a subterranean formation, and producing methane from a coal bed are also disclosed.

Robertson, Eric P (Idaho Falls, ID); Christiansen, Richard L. (Littleton, CO)

2007-05-29T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

Methods for measurement of a dimensional characteristic and methods of predictive modeling related thereto  

DOE Patents [OSTI]

A method of optically determining a change in magnitude of at least one dimensional characteristic of a sample in response to a selected chamber environment. A magnitude of at least one dimension of the at least one sample may be optically determined subsequent to altering the at least one environmental condition within the chamber. A maximum change in dimension of the at least one sample may be predicted. A dimensional measurement apparatus for indicating a change in at least one dimension of at least one sample. The dimensional measurement apparatus may include a housing with a chamber configured for accommodating pressure changes and an optical perception device for measuring a dimension of at least one sample disposed in the chamber. Methods of simulating injection of a gas into a subterranean formation, injecting gas into a subterranean formation, and producing methane from a coal bed are also disclosed.

Robertson, Eric P (Idaho Falls, ID); Christiansen, Richard L. (Littleton, CO)

2007-10-23T23:59:59.000Z

262

New probabilistic modeling and simulation methods for complex time-dependent systems  

SciTech Connect (OSTI)

This paper is a tutorial that presents a new method of modeling the probabilistic description of failure mechanisms in complex, time-dependent systems. The method of modeling employs a state vector differential equation representation of cumulative failure probabilities derived from Markov models associated with certain generic fault trees, and the method automatically includes common cause/common mode statistical dependencies, as well as time-related dependencies not considered in the literature previously. Simulations of these models employ a population dynamics representation of a probability space involving probability particle transitions among the Markov disjoint states. The particle transitions are governed by a random, Monte Carlo selection process.

Bartholomew, R.J.

1985-01-01T23:59:59.000Z

263

Solving a Two-Dimensional Elliptic Model Problem with the Conjugate Gradient Method Using  

E-Print Network [OSTI]

Solving a Two-Dimensional Elliptic Model Problem with the Conjugate Gradient Method Using Matrix Preconditioned Conjugate Gradient method in Matlab can be optimized in terms of wall clock time and, more-free Preconditioned Conjugate Gradient method. This superior algorithm computes the same numerical solution to our

Gobbert, Matthias K.

264

A Fourier-based Valuation Method for Bermudan and Barrier Options under Heston's Model  

E-Print Network [OSTI]

A Fourier-based Valuation Method for Bermudan and Barrier Options under Heston's Model Fang Fang dependency. Monte Carlo simulation methods are often used for the valuation of such products in practice and Cornelis W. Oosterlee May 4, 2010 Abstract We develop an efficient Fourier-based numerical method

Oosterlee, Cornelis W. "Kees"

265

Brinkmann Model and Double Penalization Method for the Flow Around a Porous Thin  

E-Print Network [OSTI]

the flow of a viscous fluid around a thin layer of porous material. Using a BKW method, we perform Keywords: Navier-Stokes equations, BKW method, penalization, porous ma- terial, thin layer. 1 Introduction are obtained with a BKW method. With these two asymptotic expansions, we will compare both models. We

Paris-Sud XI, Université de

266

Geometry optimization methods for modeling large molecules O don Farkasa,*, H. Bernhard Schlegelb  

E-Print Network [OSTI]

Geometry optimization methods for modeling large molecules O¨ do¨n Farkasa,*, H. Bernhard Schlegelb, Wayne State University, Detroit, USA Abstract Geometry optimization is an essential part of quantum that there are different requirements for a chosen optimization method. The proposed method aims to meet two requirements

Schlegel, H. Bernhard

267

Synthesis of Numerical Methods for Modeling Wave Energy Converter-Point Absorbers: Preprint  

SciTech Connect (OSTI)

During the past few decades, wave energy has received significant attention among all ocean energy formats. Industry has proposed hundreds of prototypes such as an oscillating water column, a point absorber, an overtopping system, and a bottom-hinged system. In particular, many researchers have focused on modeling the floating-point absorber as the technology to extract wave energy. Several modeling methods have been used such as the analytical method, the boundary-integral equation method, the Navier-Stokes equations method, and the empirical method. However, no standardized method has been decided. To assist the development of wave energy conversion technologies, this report reviews the methods for modeling the floating-point absorber.

Li, Y.; Yu, Y. H.

2012-05-01T23:59:59.000Z

268

Review of Wind Energy Forecasting Methods for Modeling Ramping Events  

SciTech Connect (OSTI)

Tall onshore wind turbines, with hub heights between 80 m and 100 m, can extract large amounts of energy from the atmosphere since they generally encounter higher wind speeds, but they face challenges given the complexity of boundary layer flows. This complexity of the lowest layers of the atmosphere, where wind turbines reside, has made conventional modeling efforts less than ideal. To meet the nation's goal of increasing wind power into the U.S. electrical grid, the accuracy of wind power forecasts must be improved. In this report, the Lawrence Livermore National Laboratory, in collaboration with the University of Colorado at Boulder, University of California at Berkeley, and Colorado School of Mines, evaluates innovative approaches to forecasting sudden changes in wind speed or 'ramping events' at an onshore, multimegawatt wind farm. The forecast simulations are compared to observations of wind speed and direction from tall meteorological towers and a remote-sensing Sound Detection and Ranging (SODAR) instrument. Ramping events, i.e., sudden increases or decreases in wind speed and hence, power generated by a turbine, are especially problematic for wind farm operators. Sudden changes in wind speed or direction can lead to large power generation differences across a wind farm and are very difficult to predict with current forecasting tools. Here, we quantify the ability of three models, mesoscale WRF, WRF-LES, and PF.WRF, which vary in sophistication and required user expertise, to predict three ramping events at a North American wind farm.

Wharton, S; Lundquist, J K; Marjanovic, N; Williams, J L; Rhodes, M; Chow, T K; Maxwell, R

2011-03-28T23:59:59.000Z

269

Soil cracking modelling using the mesh-free SPH method  

E-Print Network [OSTI]

The presence of desiccation cracks in soils can significantly alter their mechanical and hydrological properties. In many circumstances, desiccation cracking in soils can cause significant damage to earthen or soil supported structures. For example, desiccation cracks can act as the preference path way for water flow, which can facilitate seepage flow causing internal erosion inside earth structures. Desiccation cracks can also trigger slope failures and landslides. Therefore, developing a computational procedure to predict desiccation cracking behaviour in soils is vital for dealing with key issues relevant to a range of applications in geotechnical and geo-environment engineering. In this paper, the smoothed particle hydrodynamics (SPH) method will be extended for the first time to simulate shrinkage-induced soil cracking. The main objective of this work is to examine the performance of the proposed numerical approach in simulating the strong discontinuity in material behaviour and to learn about the crack ...

Bui, H H; Kodikara, J; Sanchez, M

2015-01-01T23:59:59.000Z

270

Low-Order Mathematical Modelling of Electric Double Layer Supercapacitors Using Spectral Methods  

E-Print Network [OSTI]

This work investigates two physics-based models that simulate the non-linear partial differential algebraic equations describing an electric double layer supercapacitor. In one model the linear dependence between electrolyte concentration and conductivity is accounted for, while in the other model it is not. A spectral element method is used to discretise the model equations and it is found that the error convergence rate with respect to the number of elements is faster compared to a finite difference method. The increased accuracy of the spectral element approach means that, for a similar level of solution accuracy, the model simulation computing time is approximately 50% of that of the finite difference method. This suggests that the spectral element model could be used for control and state estimation purposes. For a typical supercapacitor charging profile, the numerical solutions from both models closely match experimental voltage and current data. However, when the electrolyte is dilute or where there is...

Drummond, Ross; Duncan, Stephen R

2014-01-01T23:59:59.000Z

271

FINITE VOLUME METHODS APPLIED TO THE COMPUTATIONAL MODELLING OF WELDING PHENOMENA  

E-Print Network [OSTI]

1 FINITE VOLUME METHODS APPLIED TO THE COMPUTATIONAL MODELLING OF WELDING PHENOMENA Gareth A.Taylor@brunel.ac.uk ABSTRACT This paper presents the computational modelling of welding phenomena within a versatile numerical) and Computational Solid Mechanics (CSM). With regard to the CFD modelling of the weld pool fluid dynamics, heat

Taylor, Gary

272

A Systematic Method for the Intentional Modelling and Verification of Business  

E-Print Network [OSTI]

A Systematic Method for the Intentional Modelling and Verification of Business Applications I appears to be a good candidate for involving business people in the early modelling of business applications, reducing the risk of business-IT systems misalignment. Furthermore, in the context of Model

Paris-Sud XI, Université de

273

Special Section --Marine Controlled-Source Electromagnetic Methods A Bayesian model for gas saturation estimation  

E-Print Network [OSTI]

Special Section -- Marine Controlled-Source Electromagnetic Methods A Bayesian model for gas Vasco1 , Yoram Rubin2 , and Zhangshuan Hou2 ABSTRACT We develop a Bayesian model to jointly invert reservoir model. We consid- er the porosity and fluid saturation of each layer in the reservoir, the bulk

Chen, Jinsong

274

Multiscale CFD simulations of entrained flow gasification  

E-Print Network [OSTI]

The design of entrained flow gasifiers and their operation has largely been an experience based enterprise. Most, if not all, industrial scale gasifiers were designed before it was practical to apply CFD models. Moreover, ...

Kumar, Mayank, Ph. D. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

275

Efficient implementation of the three-dimensional reference interaction site model method in the fragment molecular orbital method  

SciTech Connect (OSTI)

The three-dimensional reference interaction site model (3D-RISM) method was efficiently implemented in the fragment molecular orbital (FMO) method. The method is referred to as the FMO/3D-RISM method, and allows us to treat electronic structure of the whole of a macromolecule, such as a protein, as well as the solvent distribution around a solute macromolecule. The formalism of the FMO/3D-RISM method, for the computationally available form and variational expressions, are proposed in detail. A major concern leading to the implementation of the method was decreasing the computational costs involved in calculating the electrostatic potential, because the electrostatic potential is calculated on numerous grid points in three-dimensional real space in the 3D-RISM method. In this article, we propose a procedure for decreasing the computational costs involved in calculating the electrostatic potential in the FMO method framework. The strategy involved in this procedure is to evaluate the electrostatic potential and the solvated Fock matrix in different manners, depending on the distance between the solute and the solvent. The electrostatic potential is evaluated directly in the vicinity of the solute molecule by integrating the molecular orbitals of monomer fragments of the solute molecule, whereas the electrostatic potential is described as the sum of multipole interactions when an analog of the fast multipole method is used. The efficiency of our method was demonstrated by applying it to a water trimer system and three biomolecular systems. The FMO/3D-RISM calculation can be performed within a reasonable computational time, retaining the accuracy of some physical properties.

Yoshida, Norio, E-mail: noriwo@chem.kyushu-univ.jp [Department of Chemistry, Graduate School of Sciences, Kyushu University, 6-10-1, Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)

2014-06-07T23:59:59.000Z

276

Multiscale Computation: Needs and Opportunities for BER Science | EMSL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recovery challenge fundProject8MistakesAdministrationVideoMultiscale

277

Quantitative Methods for Comparing Different Polyline Stream Network Models  

SciTech Connect (OSTI)

Two techniques for exploring relative horizontal accuracy of complex linear spatial features are described and sample source code (pseudo code) is presented for this purpose. The first technique, relative sinuosity, is presented as a measure of the complexity or detail of a polyline network in comparison to a reference network. We term the second technique longitudinal root mean squared error (LRMSE) and present it as a means for quantitatively assessing the horizontal variance between two polyline data sets representing digitized (reference) and derived stream and river networks. Both relative sinuosity and LRMSE are shown to be suitable measures of horizontal stream network accuracy for assessing quality and variation in linear features. Both techniques have been used in two recent investigations involving extracting of hydrographic features from LiDAR elevation data. One confirmed that, with the greatly increased resolution of LiDAR data, smaller cell sizes yielded better stream network delineations, based on sinuosity and LRMSE, when using LiDAR-derived DEMs. The other demonstrated a new method of delineating stream channels directly from LiDAR point clouds, without the intermediate step of deriving a DEM, showing that the direct delineation from LiDAR point clouds yielded an excellent and much better match, as indicated by the LRMSE.

Danny L. Anderson; Daniel P. Ames; Ping Yang

2014-04-01T23:59:59.000Z

278

Modeling of multicomponent radiatively driven stellar winds using a Newton-Raphson method  

E-Print Network [OSTI]

We present a simple method for the solution of one-component and multicomponent hydrodynamic equations based on the Newton-Raphson method. We show that this method can be used for the solution of stationary hydrodynamic equations. This method has been used for the calculation of the low density stellar wind models for which the multicomponent nature of the wind influences the overall wind structure.

J. Krticka

2003-03-03T23:59:59.000Z

279

Variational Multiscale Modeling of Biomolecular Complexes , Xin Feng2  

E-Print Network [OSTI]

. Surface definitions and defects Molecular surface of protein (ID:1PPL) and its geometric singularity. We (Right Chart) of a protein (ID:1PPL). The Generalized Poisson-Boltzmann equation is solved to obtain

280

Continuum-based Multiscale Computational Damage Modeling of Cementitous Composites  

E-Print Network [OSTI]

of ? , and its comparison with experimental results by Kupfer et al. (1969) ...... 32 5.1 Evolution of the damage due to the change of the compressive hardening modulus Q ? for: (a) Exponential damage evolution law in Eq. (2.48) and (b) power damage... evolution law in Eq. (2.52) ............... 71 5.2 Evolution of the damage due to the change of the compressive hardening rate constant b? for: (a) Exponential damage evolution law in Eq. (2.48) and (b) power damage evolution law in Eq. (2...

Kim, Sun-Myung

2011-08-08T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

Sketch interpretation using multiscale stochastic models of temporal patterns  

E-Print Network [OSTI]

Sketching is a natural mode of interaction used in a variety of settings. For example, people sketch during early design and brainstorming sessions to guide the thought process; when we communicate certain ideas, we use ...

Sezgin, Tevfik Metin, 1978-

2006-01-01T23:59:59.000Z

282

High-resolution, multi-scale modeling of watershed hydrology  

E-Print Network [OSTI]

Enrique R. Vivoni An Opportunity to Integrate Remote Sensing Observations, Field Data Collection distribution of topography, rainfall, soils, vegetation, meteorology, soil moisture. Field Data and Remote's Hydrologic and Energetic System: Water and Heat Storages and Transports over Many Time and Space Scales P ET

Vivoni, Enrique R.

283

An Analysis Platform for Multiscale Hydrogeologic Modeling with Emphasis on  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone by E-mail ShareRed Cross Blood DriveoverCarbonAmyHybrid

284

A stochastic multiscale model for electricity generation capacity ...  

E-Print Network [OSTI]

mand response requires a coupling of both the long and short term dynamics. ... Division, Massachusetts Institute of Technology, 77 Massachusetts Ave, Building ... or demand elasticity (a major objective of demand response programs).

2011-04-21T23:59:59.000Z

285

Multi-Scale Indentation Hardness Testing; A Correlation and Model  

E-Print Network [OSTI]

. This test is performed by applying a steady load to an indenter (most commonly a diamond pyramid, diamond spheroconical, or a tungsten carbide ball) and then calculating the hardness from the area or depth of the 5 indentation. A dynamic indentation test... 6 variants are the indenter tip and the load applied. A tungsten carbide sphere or a diamond cone or pyramid is used to prevent the indenter tip from being damaged by the test piece. This consideration is made because test pieces have unique values...

Bennett, Damon W.

2010-01-20T23:59:59.000Z

286

a uniformly accurate multiscale time integrator pseudospectral ...  

E-Print Network [OSTI]

reported to confirm the error bounds and demonstrate the efficiency and accuracy of the MTI-FP method for the ... AMS subject classifications. 65M12, 65M15 ... and then the KG equation (1.1) conserves the energy [5, 20, 21, 32]. E(t) := ?. Rd.

2014-10-14T23:59:59.000Z

287

Method for estimation of gravitational-wave transient model parameters in frequency-time maps  

E-Print Network [OSTI]

A common technique for detection of gravitational-wave signals is searching for excess power in frequency-time maps of gravitational-wave detector data. In the event of a detection, model selection and parameter estimation will be performed in order to explore the properties of the source. In this paper, we develop a Bayesian statistical method for extracting model-dependent parameters from observed gravitational-wave signals in frequency-time maps. We demonstrate the method by recovering the parameters of model gravitational-wave signals added to simulated advanced LIGO noise. We also characterize the performance of the method and discuss prospects for future work.

Michael Coughlin; Nelson Christensen; Jonathan Gair; Shivaraj Kandhasamy; Eric Thrane

2014-04-17T23:59:59.000Z

288

Precise estimation of shell model energy by second order extrapolation method  

E-Print Network [OSTI]

A second order extrapolation method is presented for shell model calculations, where shell model energies of truncated spaces are well described as a function of energy variance by quadratic curves and exact shell model energies can be obtained by the extrapolation. This new extrapolation can give more precise energy than those of first order extrapolation method. It is also clarified that first order extrapolation gives a lower limit of shell model energy. In addition to the energy, we derive the second order extrapolation formula for expectation values of other observables.

Takahiro Mizusaki; Masatoshi Imada

2003-02-20T23:59:59.000Z

289

Modeling and identification of parallel nonlinear systems: Structural classification and parameter estimation methods  

SciTech Connect (OSTI)

Structural classification and parameter estimation (SCPE) methods are used for studying single-input single-output (SISO) parallel linear-nonlinear-linear (LNL), linear-nonlinear (LN), and nonlinear-linear (NL) system models from input-output (I-O) measurements. The uniqueness of the I-O mappings (see the definition of the I-O mapping in Section 3-A) of some model structures is discussed. The uniqueness of the I-O mappings (see the definition of the I-O mapping in Section 3-A) of some model structures is discussed. The uniqueness of I-O mappings of different models tells them in what conditions different model structures can be differentiated from one another. Parameter uniqueness of the I-O mapping of a given structural model is also discussed, which tells the authors in what conditions a given model's parameters can be uniquely estimated from I-O measurements. These methods are then generalized so that they can be used to study single-input multi-output (SIMO), multi-input single-output (MISO), as well as multi-input multi-output (MIMO) nonlinear system models. Parameter estimation of the two-input single-output nonlinear system model (denoted as the 2f-structure in 2 cited references), which was left unsolved previously, can now be obtained using the newly derived algorithms. Applications of SCPE methods for modeling visual cortical neurons, system fault detection, modeling and identification of communication networks, biological systems, and natural and artificial neural networks are also discussed. The feasibility of these methods is demonstrated using simulated examples. SCPE methods presented in this paper can be further developed to study more complicated block-structures models, and will therefore have future potential for modeling and identifying highly complex multi-input multi-output nonlinear systems.

Chen, H.W. (Los Alamos National Lab., NM (United States). Biophysics Group M715)

1995-01-01T23:59:59.000Z

290

A FAST MODEL-BUILDING METHOD FOR TIME SERIES USING GENETIC PROGRAMMING  

E-Print Network [OSTI]

A FAST MODEL-BUILDING METHOD FOR TIME SERIES USING GENETIC PROGRAMMING I. Yoshihara Faculty) financial problems e.g. stock price indices and gold prices. The experiments lead us to the conclusion

Fernandez, Thomas

291

Thermo-Poroelastic Modeling of Reservoir Stimulation and Microseismicity Using Finite Element Method with Damage Mechanics  

E-Print Network [OSTI]

, changing rock permeability. In this work, two- and three-dimensional finite element methods were developed to simulate coupled reservoirs with damage mechanics and stress-dependent permeability. The model considers the influence of fluid flow, temperature...

Lee, Sang Hoon

2012-02-14T23:59:59.000Z

292

Evaluating and developing parameter optimization and uncertainty analysis methods for a computationally intensive distributed hydrological model  

E-Print Network [OSTI]

This study focuses on developing and evaluating efficient and effective parameter calibration and uncertainty methods for hydrologic modeling. Five single objective optimization algorithms and six multi-objective optimization algorithms were tested...

Zhang, Xuesong

2009-05-15T23:59:59.000Z

293

E-Print Network 3.0 - agent-based modeling methods Sample Search...  

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

and Information Sciences ; Biology and Medicine 5 Tutorial on agent-based modelling and simulation CM Macal1,2 Summary: of disciplines (Section 3), and identify methods and...

294

The Pugh Controlled Convergence Method: Model-Based Evaluation and Implications for Design Theory  

E-Print Network [OSTI]

This paper evaluates the Pugh Controlled Convergence method and its relationship to recent developments in design theory. Computer executable models are proposed simulating a team of people involved in iterated cycles of ...

Wijnia, Ype

295

Hydrologic modeling to screen potential environmental management methods for malaria vector control in Niger  

E-Print Network [OSTI]

This paper describes the first use of Hydrology-Entomology and Malaria Transmission Simulator (HYDREMATS), a physically based distributed hydrology model, to investigate environmental management methods for malaria vector ...

Gianotti, Rebecca Louise

296

3D Weak-Dispersion Reverse-Time Migration with a StereoModeling Method  

E-Print Network [OSTI]

The finite difference method has been widely used in seismic modeling and reverse time migration. However, it generally has two issues: large computational cost and numerical dispersion. Recently, a nearly-analytic discrete ...

Li, Jingshuang

2013-01-01T23:59:59.000Z

297

A multi-resolution method for climate system modeling: application of Spherical Centroidal A multi-resolution method for climate system modeling: Application of Spherical Centroidal Voroni Tessellations  

SciTech Connect (OSTI)

During the next decade and beyond, climate system models will be challenged to resolve scales and processes that are far beyond their current scope. Each climate system component has its prototypical example of an unresolved process that may strongly influence the global climate system, ranging from eddy activity within ocean models, to ice streams within ice sheet models, to surface hydrological processes within land system models, to cloud processes within atmosphere models. These new demands will almost certainly result in the develop of multi-resolution schemes that are able, at least regional to faithfully simulate these fine-scale processes. Spherical Centroidal Voronoi Tessellations (SCVTs) offer one potential path toward the development of robust, multi-resolution climate system component models, SCVTs allow for the generation of high quality Voronoi diagrams and Delaunay triangulations through the use of an intuitive, user-defined density function, each of the examples provided, this method results in high-quality meshes where the quality measures are guaranteed to improve as the number of nodes is increased. Real-world examples are developed for the Greenland ice sheet and the North Atlantic ocean. Idealized examples are developed for ocean-ice shelf interaction and for regional atmospheric modeling. In addition to defining, developing and exhibiting SCVTs, we pair this mesh generation technique with a previously developed finite-volume method. Our numerical example is based on the nonlinear shallow-water equations spanning the entire surface of the sphere. This example is used to elucidate both the potential benefits of this multi-resolution method and the challenges ahead.

Ringler, Todd D [Los Alamos National Laboratory; Gunzburger, Max [FLORIDA STATE UNIV; Ju, Lili [UNIV OF SOUTH CAROLINA

2008-01-01T23:59:59.000Z

298

A Novel Sensitive Method of Detecting Mnemonic Decline in Mouse Model of Alzheimer's Disease  

E-Print Network [OSTI]

of the requirements for the designation as UNDERGRADUATE RESEARCH SCHOLAR A Junior Scholars Thesis by REBECCA KAYE SIMMONS A NOVEL SENSITIVE METHOD OF DETECTING MNEMONIC DECLINE IN MOUSE MODEL OF ALZHEIMER?S DISEASE Approved by: Research... as UNDERGRADUATE RESEARCH SCHOLAR A Junior Scholars Thesis by REBECCA KAYE SIMMONS iii ABSTRACT A Novel Sensitive Method of Detecting Mnemonic Decline in Mouse Models of Alzheimer?s Disease. (April 2009) Rebecca Kaye Simmons Department of Psychology...

Simmons, Rebecca

2011-01-11T23:59:59.000Z

299

A Conformal Mapping Grid Generation Method for Modeling High-Fidelity Aeroelastic Simulations  

E-Print Network [OSTI]

A CONFORMAL MAPPING GRID GENERATION METHOD FOR MODELING HIGH-FIDELITY AEROELASTIC SIMULATIONS A Thesis by GREGORY DORWAY WORLEY Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements... for the degree of MASTER OF SCIENCE May 2010 Major Subject: Aerospace Engineering A CONFORMAL MAPPING GRID GENERATION METHOD FOR MODELING HIGH-FIDELITY AEROELASTIC SIMULATIONS A Thesis by GREGORY DORWAY WORLEY Submitted to the O ce of Graduate Studies of Texas A...

Worley, Gregory

2010-07-14T23:59:59.000Z

300

Collocation method for the modeling of membrane gas permeation systems A. Feichtingera  

E-Print Network [OSTI]

) or hydrogen recovery from biomass gasification gases (Mayer et al., 2010; Makaruk et al., 2012). CorrespondingCollocation method for the modeling of membrane gas permeation systems A. Feichtingera , A simulation, collocation method, error estimate, grid adaptation, multicomponent separation 1. Introduction

Weinmüller, Ewa B.

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


301

Multiple temperature kinetic model and gas-kinetic method for hypersonic non-equilibrium flow computations  

E-Print Network [OSTI]

Multiple temperature kinetic model and gas-kinetic method for hypersonic non-equilibrium flow. For the non-equilibrium flow computations, i.e., the nozzle flow and hypersonic rarefied flow over flat plate-kinetic method; Hypersonic and rarefied flows 1. Introduction The development of aerospace technology has

Xu, Kun

302

Sensitivity of Ocean-Atmosphere Coupled Models to the Coupling Method : Example of Tropical Cyclone  

E-Print Network [OSTI]

Sensitivity of Ocean-Atmosphere Coupled Models to the Coupling Method : Example of Tropical Cyclone and propagation of tropical cyclone Erica. Sensitiv- ity tests to the coupling method are carried out-sea feedbacks. Separate integrations of the Corresponding author. Phone: +33 (0)4 76 51 48 60 Fax: +33 (0)4 76

303

A General Method for Conserving Energy and Potential Enstrophy in Shallow-Water Models  

E-Print Network [OSTI]

A General Method for Conserving Energy and Potential Enstrophy in Shallow-Water Models RICK SALMON numerical models that conserve analogs of the energy and potential enstrophy; one need only discretize, in the inviscid limit, conserve energy and an arbitrary ad- ditional invariant related to the potential vorticity

Salmon, Rick

304

Methods Mol Biol . Author manuscript 3D structural models of transmembrane proteins  

E-Print Network [OSTI]

proteins is a major research area. Due to the lack of available 3D structures, automatic homology modelingMethods Mol Biol . Author manuscript Page /1 9 3D structural models of transmembrane proteins: Alexandre De Brevern Abstract Summary Transmembrane proteins

Paris-Sud XI, Université de

305

Approximation Methods for Pricing Problems under the Nested Logit Model with Price Bounds  

E-Print Network [OSTI]

Approximation Methods for Pricing Problems under the Nested Logit Model with Price Bounds W@orie.cornell.edu November 13, 2012 Abstract We consider two variants of a pricing problem under the nested logit model. In the first variant, the set of products offered to customers is fixed and we want to determine the prices

Topaloglu, Huseyin

306

Bayesian methods for the quantification of uncertainties in syngas chemistry models  

E-Print Network [OSTI]

Bayesian methods for the quantification of uncertainties in syngas chemistry models Kalen Braman, Todd Oliver and Venkat Raman, The University of Texas, Austin, Texas, 78712 Syngas chemistry modeling is an integral step toward the development of safe and ef- ficient syngas combustors. Although substantial effort

Raman, Venkat

307

A Formal Method for Attack Modeling and Seyit Ahmet C amtepe and Bulent Yener  

E-Print Network [OSTI]

1 A Formal Method for Attack Modeling and Detection Seyit Ahmet C¸ amtepe and B¨ulent Yener,yener}@cs.rpi.edu TR-06-01 Abstract This paper presents a formal methodology for attack modeling and detection for networks. Our approach has three phases. First, we extend the basic attack tree approach [1] to capture (i

Bystroff, Chris

308

Incident and in situ irradiance in Lakes Cadagno and Lucerne: A comparison of methods and models  

E-Print Network [OSTI]

Incident and in situ irradiance in Lakes Cadagno and Lucerne: A comparison of methods and models Key words: Lake Lucerne, Lake Cadagno, PAR, UV-A, UV-B, irradiance regime, radiative transfer models) at the field stations Kastanienbaum at Lake Lucerne (434 m a.s.l.) and Piora at Lake Cadagno (1923 m a

Sommaruga, Ruben

309

Investigating Causal Relations by Econometric Models and Cross-spectral Methods C. W. J. Granger  

E-Print Network [OSTI]

Investigating Causal Relations by Econometric Models and Cross-spectral Methods C. W. J. Granger-9682%28196908%2937%3A3%3C424%3AICRBEM%3E2.0.CO%3B2-L Econometrica is currently published by The Econometric Society #12;Econometrics, Vol. 37, No. 3 (July, 1969) INVESTIGATING CAUSAL RELATIONS BY ECONOMETRIC MODELS

Timmer, Jens

310

A Fiber Tracking Method for Building Patient Specific Dynamic Musculoskeletal Models from  

E-Print Network [OSTI]

A Fiber Tracking Method for Building Patient Specific Dynamic Musculoskeletal Models from Diffusion tracking algorithm based on an energy minimizing active curve that is well suited for building these strand and FEM models are complex to construct and time intensive to simulate. Recently a new simulation

Gilles, Benjamin

311

Assessing nitrogen losses after sewage sludge spreading: A method based on simulation models and spreader  

E-Print Network [OSTI]

1 Assessing nitrogen losses after sewage sludge spreading: A method based on simulation models performances. We define 45 sewage sludge spreading scenarios covering a wide range of situations in France. Several models are used to (i) assess nitrogen losses due to sewage sludge spreading and (ii) calculate

Paris-Sud XI, Université de

312

Sensitivity of an Ocean-Atmosphere Coupled Model to the Coupling Method : Study of Tropical Cyclone  

E-Print Network [OSTI]

Sensitivity of an Ocean-Atmosphere Coupled Model to the Coupling Method : Study of Tropical Cyclone) in a realistic configuration aiming at simulating the genesis and propagation of tropical cyclone Erica and Oceanic Coupled Models (AOCMs) which account for important air-sea feedbacks. Separate integrations

Recanati, Catherine

313

Harmonic Modelling of Thyristor Bridges using a Simplified Time Domain Method  

E-Print Network [OSTI]

1 Harmonic Modelling of Thyristor Bridges using a Simplified Time Domain Method P. W. Lehn, Senior form solution for the harmonic injection of the converter is developed. For the more general case model module takes as input the ac voltage harmonics at the point of common coupling and outputs

Lehn, Peter W.

314

Supersonic combustion studies using a multivariate quadrature based method for combustion modeling  

E-Print Network [OSTI]

Supersonic combustion studies using a multivariate quadrature based method for combustion modeling function (PDF) of thermochemical variables can be used for accurately computing the combustion source term of predictive models for supersonic combustion is a critical step in design and development of scramjet engines

Raman, Venkat

315

An XFEM Model for Carbon Sequestration Journal: International Journal for Numerical Methods in Engineering  

E-Print Network [OSTI]

PeerReview Only An XFEM Model for Carbon Sequestration Journal: International Journal for Numerical method, Carbon Sequestration, Multiphase flow, XFEM, Multifield systems, Petrov-Galerkin httpScience (www.interscience.wiley.com). DOI: 10.1002/nme An XFEM Model for Carbon Sequestration Chris Ladubec

Gracie, Robert

316

ERDC/ELTR-11-2 Methods for Tier 2 Modeling within the  

E-Print Network [OSTI]

and groundwater systems and to assess range management strategies to protect human and environmental health. Tier 2 will consist of time-varying contaminant fate/transport models for soil, vadose zone, groundwaterERDC/ELTR-11-2 Methods for Tier 2 Modeling within the Training Range Environmental Evaluation

US Army Corps of Engineers

317

Method to Filter ECGs and Evaluate Clinical Parameter Distortion using Realistic ECG Model Parameter Fitting  

E-Print Network [OSTI]

Method to Filter ECGs and Evaluate Clinical Parameter Distortion using Realistic ECG Model Abstract By fitting a previously published nonlinear model for generating realistic ECG to waveforms, the authors demonstrate that significant points (P, Q, R, S, and T) on the ECG can be determined

McSharry, Patrick E.

318

Physics-based statistical model and simulation method of RF propagation in urban environments  

DOE Patents [OSTI]

A physics-based statistical model and simulation/modeling method and system of electromagnetic wave propagation (wireless communication) in urban environments. In particular, the model is a computationally efficient close-formed parametric model of RF propagation in an urban environment which is extracted from a physics-based statistical wireless channel simulation method and system. The simulation divides the complex urban environment into a network of interconnected urban canyon waveguides which can be analyzed individually; calculates spectral coefficients of modal fields in the waveguides excited by the propagation using a database of statistical impedance boundary conditions which incorporates the complexity of building walls in the propagation model; determines statistical parameters of the calculated modal fields; and determines a parametric propagation model based on the statistical parameters of the calculated modal fields from which predictions of communications capability may be made.

Pao, Hsueh-Yuan (San Jose, CA); Dvorak, Steven L. (Tucson, AZ)

2010-09-14T23:59:59.000Z

319

Multi-scale theories for the MJO Andrew J. Majda and Samuel N. Stechmann  

E-Print Network [OSTI]

Multi-scale theories for the MJO Andrew J. Majda and Samuel N. Stechmann November 24, 2010 1 MJO events (Lin and Johnson, 1996; Yanai et al., 2000; Houze et al., 2000). From these ob- servations

Stechmann, Samuel N.

320

Bootstrap multiscale analysis and localization for multi-particle continuous Anderson Hamiltonians  

E-Print Network [OSTI]

We extend the bootstrap multiscale analysis developed by Germinet and Klein to the multi-particle continuous Anderson Hamiltonian, obtaining Anderson localization with finite multiplicity of eigenvalues, decay of eigenfunction correlations, and a strong form of dynamical localization.

Abel Klein; Son Nguyen

2014-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

Multiscale Physical and Biological Dynamics in the Philippine Archipelago: Predictions and Processes  

E-Print Network [OSTI]

The Philippine Archipelago is remarkable because of its complex geometry, with multiple islands and passages, and its multiscale dynamics, from the large-scale open-ocean and atmospheric forcing, to the strong tides and ...

Lermusiaux, Pierre F. J.

322

University of Maryland component of the Center for Multiscale Plasma Dynamics: Final Technical Report  

SciTech Connect (OSTI)

The Center for Multiscale Plasma Dynamics (CMPD) was a five-year Fusion Science Center. The University of Maryland (UMD) and UCLA were the host universities. This final technical report describes the physics results from the UMD CMPD.

Dorland, William [University of Maryland

2014-11-18T23:59:59.000Z

323

STOCHASTIC METHODS FOR THE PREDICTION OF  

E-Print Network [OSTI]

STOCHASTIC METHODS FOR THE PREDICTION OF COMPLEX MULTISCALE PHENOMENA James Glimm, \\Lambda Alamos, NM 87545 Abstract The purpose of this paper is to develop a general framework for the prediction of current interest to the authors. Prediction involves a two step process of inverse prediction to describe

New York at Stoney Brook, State University of

324

Models with time-dependent parameters using transform methods: application to Heston's model  

E-Print Network [OSTI]

This paper presents a methodology to introduce time-dependent parameters for a wide family of models preserving their analytic tractability. This family includes hybrid models with stochastic volatility, stochastic interest-rates, jumps and their non-hybrid counterparts. The methodology is applied to Heston's model. A bootstrapping algorithm is presented for calibration. A case study works out the calibration of the time-dependent parameters to the volatility surface of the Eurostoxx 50 index. The methodology is also applied to the analytic valuation of forward start vanilla options driven by Heston's model. This result is used to explore the forward skew of the case study.

Elices, A

2007-01-01T23:59:59.000Z

325

Computing observables in curved multifield models of inflation - A guide (with code) to the transport method  

E-Print Network [OSTI]

We describe how to apply the transport method to compute inflationary observables in a broad range of multiple-field models. The method is efficient and encompasses scenarios with curved field-space metrics, violations of slow-roll conditions and turns of the trajectory in field space. It can be used for an arbitrary mass spectrum, including massive modes and models with quasi-single-field dynamics. In this note we focus on practical issues. It is accompanied by a Mathematica code which can be used to explore suitable models, or as a basis for further development.

Mafalda Dias; Jonathan Frazer; David Seery

2015-02-10T23:59:59.000Z

326

Computing observables in curved multifield models of inflation - A guide (with code) to the transport method  

E-Print Network [OSTI]

We describe how to apply the transport method to compute inflationary observables in a broad range of multiple-field models. The method is efficient and encompasses scenarios with curved field-space metrics, violations of slow-roll conditions and turns of the trajectory in field space. It can be used for an arbitrary mass spectrum, including massive modes and models with quasi-single-field dynamics. In this note we focus on practical issues. It is accompanied by a Mathematica code which can be used to explore suitable models, or as a basis for further development.

Dias, Mafalda; Seery, David

2015-01-01T23:59:59.000Z

327

Computational model, method, and system for kinetically-tailoring multi-drug chemotherapy for individuals  

DOE Patents [OSTI]

A method and system for tailoring treatment regimens to individual patients with diseased cells exhibiting evolution of resistance to such treatments. A mathematical model is provided which models rates of population change of proliferating and quiescent diseased cells using cell kinetics and evolution of resistance of the diseased cells, and pharmacokinetic and pharmacodynamic models. Cell kinetic parameters are obtained from an individual patient and applied to the mathematical model to solve for a plurality of treatment regimens, each having a quantitative efficacy value associated therewith. A treatment regimen may then be selected from the plurlaity of treatment options based on the efficacy value.

Gardner, Shea Nicole (San Leandro, CA)

2007-10-23T23:59:59.000Z

328

Nonlinear generalized source method for modeling second-harmonic generation in diffraction gratings  

E-Print Network [OSTI]

We introduce a versatile numerical method for modeling light diffraction in periodically patterned photonic structures containing quadratically nonlinear non-centrosymmetric optical materials. Our approach extends the generalized source method to nonlinear optical interactions by incorporating the contribution of nonlinear polarization sources to the diffracted field in the algorithm. We derive the mathematical formalism underlying the numerical method and introduce the Fourier-factorization suitable for nonlinear calculations. The numerical efficiency and runtime characteristics of the method are investigated in a set of benchmark calculations: the results corresponding to the fundamental frequency are compared to those obtained from a reference method and the beneficial effects of the modified Fourier-factorization rule on the accuracy of the nonlinear computations is demonstrated. In order to illustrate the capabilities of our method, we employ it to demonstrate strong enhancement of second-harmonic genera...

Weismann, Martin; Panoiu, Nicolae C

2015-01-01T23:59:59.000Z

329

STATISTICAL METHODS STATISTICAL METHODS  

E-Print Network [OSTI]

STATISTICAL METHODS 1 STATISTICAL METHODS Arnaud Delorme, Swartz Center for Computational@salk.edu. Keywords: statistical methods, inference, models, clinical, software, bootstrap, resampling, PCA, ICA Abstract: Statistics represents that body of methods by which characteristics of a population are inferred

Delorme, Arnaud

330

The numerical solution of a nickel-cadmium battery cell model using the method of lines  

E-Print Network [OSTI]

THE NUMERICAL SOLUTION OF A NICKEL-CADMIUM BATTERY CELL MODEL USING THE METHOD OF LINES A Thesis by TESHOME HAILU Submitted to the Office of Graduate Studies Texas Adi:M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1990 Major Subject: Chemical Engineering THE NUMERICAL SOLUTION OF A NICKEL-CADMIUM BATTERY CELL MODEL USING THE METHOD OF LINES A Thesis by TESHOME HAILU Approved as to style and content by: Ralph E. White (Chairman...

Hailu, Teshome

1990-01-01T23:59:59.000Z

331

Multiscale Variability of the Flow during the North American Monsoon Experiment RICHARD H. JOHNSON, PAUL E. CIESIELSKI, BRIAN D. MCNOLDY, PETER J. ROGERS, AND  

E-Print Network [OSTI]

Multiscale Variability of the Flow during the North American Monsoon Experiment RICHARD H. JOHNSON H. Johnson, Dept

Johnson, Richard H.

332

Decoupled Modeling of Chilled Water Cooling Coils Using a Finite Element Method  

E-Print Network [OSTI]

Decoupled Modeling of Chilled Water Cooling Coils Using a Finite Element Method Gang Wang Research Associate University of Nebraska – Lincoln Mingsheng Liu Professor University of Nebraska – Lincoln David E. Claridge Professor Texas A... be decoupled using a constant sensible heat ratio (SHR) and the saturation humidity ratio vs. temperature curve can be treated as linear in a small area corresponding to a finite element of the coil. This paper presents the decoupled cooling coil model...

Wang, G.; Liu, M.

2005-01-01T23:59:59.000Z

333

Smoothed Particle Inference: A Kilo-Parametric Method for X-ray Galaxy Cluster Modeling  

SciTech Connect (OSTI)

We propose an ambitious new method that models the intracluster medium in clusters of galaxies as a set of X-ray emitting smoothed particles of plasma. Each smoothed particle is described by a handful of parameters including temperature, location, size, and elemental abundances. Hundreds to thousands of these particles are used to construct a model cluster of galaxies, with the appropriate complexity estimated from the data quality. This model is then compared iteratively with X-ray data in the form of adaptively binned photon lists via a two-sample likelihood statistic and iterated via Markov Chain Monte Carlo. The complex cluster model is propagated through the X-ray instrument response using direct sampling Monte Carlo methods. Using this approach the method can reproduce many of the features observed in the X-ray emission in a less assumption-dependent way that traditional analyses, and it allows for a more detailed characterization of the density, temperature, and metal abundance structure of clusters. Multi-instrument X-ray analyses and simultaneous X-ray, Sunyaev-Zeldovich (SZ), and lensing analyses are a straight-forward extension of this methodology. Significant challenges still exist in understanding the degeneracy in these models and the statistical noise induced by the complexity of the models.

Peterson, John R.; Marshall, P.J.; /KIPAC, Menlo Park; Andersson, K.; /Stockholm U. /SLAC

2005-08-05T23:59:59.000Z

334

Constructal multi-scale package of vertical channels with natural convection and maximal heat transfer density. CONSTRUCTAL DESIGN: THE GENERATION OF MULTI-SCALE HEAT  

E-Print Network [OSTI]

transfer density. CONSTRUCTAL DESIGN: THE GENERATION OF MULTI-SCALE HEAT AND FLUID FLOW STRUCTURES-scale structures in natural convection with the objective of maximizing the heat transfer density, or the heat transfer rate per unit of volume§ . The flow volume is filled with vertical equidistant heated blades

Kihm, IconKenneth David

335

Model-based performance monitoring: Review of diagnostic methods and chiller case study  

SciTech Connect (OSTI)

The paper commences by reviewing the variety of technical approaches to the problem of detecting and diagnosing faulty operation in order to improve the actual performance of buildings. The review covers manual and automated methods, active testing and passive monitoring, the different classes of models used in fault detection, and methods of diagnosis. The process of model-based fault detection is then illustrated by describing the use of relatively simple empirical models of chiller energy performance to monitor equipment degradation and control problems. The CoolTools(trademark) chiller model identification package is used to fit the DOE-2 chiller model to on-site measurements from a building instrumented with high quality sensors. The need for simple algorithms to reject transient data, detect power surges and identify control problems is discussed, as is the use of energy balance checks to detect sensor problems. The accuracy with which the chiller model can be expected! to predict performance is assessed from the goodness of fit obtained and the implications for fault detection sensitivity and sensor accuracy requirements are discussed. A case study is described in which the model was applied retroactively to high-quality data collected in a San Francisco office building as part of a related project (Piette et al. 1999).

Haves, Phil; Khalsa, Sat Kartar

2000-05-01T23:59:59.000Z

336

Continuum Models of Carbon Nanotube-Based Composites Using the Boundary Element Method  

E-Print Network [OSTI]

Continuum Models of Carbon Nanotube-Based Composites Using the Boundary Element Method Y.J. Liu)-based composites. Carbon nanotubes, formed conceptually by rolling thin graphite sheets, have been found to be extremely stiff, strong and resilient, and therefore may be ideal for reinforcing composite materials

Liu, Yijun

337

Accepted in Methods Mol Biol. 2010 3D-structural models of transmembrane proteins.  

E-Print Network [OSTI]

of transmembrane proteins is a major research area. Due to the lack of available 3D structures, automatic homology1 Accepted in Methods Mol Biol. 2010 3D-structural models of transmembrane proteins. Alexandre G proteins are macromolecules implicated in major biological process and diseases. Due to their specific

Paris-Sud XI, Université de

338

Finite-Volume-Particle Methods for Models of Transport of Pollutant in Shallow Water  

E-Print Network [OSTI]

Finite-Volume-Particle Methods for Models of Transport of Pollutant in Shallow Water Alina Chertock of shallow water equations and the pollutant propagation is described by a transport equation. The idea and the pollution computations: the shallow water equations are numerically integrated using a #12;nite- volume

Kurganov, Alexander

339

Robust model based control method for wind energy production A. Pintea 1  

E-Print Network [OSTI]

Robust model based control method for wind energy production A. Pintea 1 , D. Popescu 1 , Ioana change effects will come to dominate every part of the earth. Wind power energy represents an interesting alternative to traditional forms of obtaining energy. However, the efficiency of wind power strongly depends

Boyer, Edmond

340

COMPARISON OF SEISMIC RISK ESTIMATES USING DIFFERENT METHODS TO MODEL FRAGILITY  

E-Print Network [OSTI]

1 COMPARISON OF SEISMIC RISK ESTIMATES USING DIFFERENT METHODS TO MODEL FRAGILITY Pierre Gehl1 , Ariane Ducellier2 , Caterina Negulescu3 , Jaime Abad4 and John Douglas5 Seismic risk evaluations play of decades hundreds of such studies have been conducted. However, the assessment of seismic risk is always

Note: This page contains sample records for the topic "method multiscale modeling" 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 implicit level set method for modeling hydraulically driven fractures Anthony Peirce a,*, Emmanuel Detournay b  

E-Print Network [OSTI]

An implicit level set method for modeling hydraulically driven fractures Anthony Peirce a the relevant tip asymptotics in hydraulic fracture simulators is critical for the accuracy and stability for a propagating hydraulic fracture. A number of char- acteristics of the governing equations for hydraulic

Peirce, Anthony

342

Comparison of multivariate methods for inferential modeling of soil carbon using visible/near-infrared spectra  

E-Print Network [OSTI]

Comparison of multivariate methods for inferential modeling of soil carbon using visible/near-infrared Diffuse reflectance spectroscopy Visible/near-infrared spectroscopy Multivariate calibration Pre-processing transformations In order to reduce costs and time in the analysis of soil properties, visible/near-infrared

Grunwald, Sabine

343

Numerical methods for the simulation of a corrosion model in a nuclear waste deep repository $  

E-Print Network [OSTI]

Numerical methods for the simulation of a corrosion model in a nuclear waste deep repository $ C of the French nuclear waste management agency ANDRA, investigations are conducted to optimize and finalize by the Nuclear Waste Management Agency ANDRA Corresponding author. Phone: +49 30 20372 560, Fax: +49 30 2044975

Paris-Sud XI, Université de

344

Evaluating variable switching and flash methods in modeling carbon sequestration in deep geologic formations  

E-Print Network [OSTI]

Evaluating variable switching and flash methods in modeling carbon sequestration in deep geologic performance computing to assess the risks involved in carbon sequestration in deep geologic formations-thermal- chemical processes in variably saturated, non-isothermal porous media is applied to sequestration

Mills, Richard

345

A New Method for Modeling and Solving the Protein Fold Recognition Problem  

E-Print Network [OSTI]

Idstract A New Method for Modeling and Solving the Protein Fold Recognition Problem (Extended}@ornl.gov Computational recognition of native-like folds from a protein fold database is considered to be a promising recog- nition through optimally aligning (threading) an amino acid sequence and a protein fold (template

Istrail, Sorin

346

Control method and system for hydraulic machines employing a dynamic joint motion model  

DOE Patents [OSTI]

A control method and system for controlling a hydraulically actuated mechanical arm to perform a task, the mechanical arm optionally being a hydraulically actuated excavator arm. The method can include determining a dynamic model of the motion of the hydraulic arm for each hydraulic arm link by relating the input signal vector for each respective link to the output signal vector for the same link. Also the method can include determining an error signal for each link as the weighted sum of the differences between a measured position and a reference position and between the time derivatives of the measured position and the time derivatives of the reference position for each respective link. The weights used in the determination of the error signal can be determined from the constant coefficients of the dynamic model. The error signal can be applied in a closed negative feedback control loop to diminish or eliminate the error signal for each respective link.

Danko, George (Reno, NV)

2011-11-22T23:59:59.000Z

347

AN EFFICIENT METHOD FOR MODELING HIGH-MAGNIFICATION PLANETARY MICROLENSING EVENTS  

SciTech Connect (OSTI)

I present a previously unpublished method for calculating and modeling multiple lens microlensing events that is based on the image centered ray-shooting approach of Bennett and Rhie. It has been used to model a wide variety of binary and triple lens systems, but it is designed to efficiently model high-magnification planetary microlensing events, because these high-magnification events are, by far, the most challenging events to model. It is designed to be efficient enough to handle complicated microlensing events, which include more than two lens masses and lens orbital motion. This method uses a polar coordinate integration grid with a smaller grid spacing in the radial direction than in the angular direction, and it employs an integration scheme specifically designed to handle limb-darkened sources. I present tests that show that these features achieve second-order accuracy for the light curves of a number of high-magnification planetary events. They improve the precision of the calculations by a factor of >100 compared to first-order integration schemes with the same grid spacing in both directions (for a fixed number of grid points). This method also includes a {chi}{sup 2} minimization method, based on the Metropolis algorithm, that allows the jump function to vary in a way that allows quick convergence to {chi}{sup 2} minima. Finally, I introduce a global parameter space search strategy that allows a blind search of parameter space for light curve models without requiring {chi}{sup 2} minimization over a large grid of fixed parameters. Instead, the parameter space is explored on a grid of initial conditions for a set of {chi}{sup 2} minimizations using the full parameter space. While this method may be somewhat faster than methods that find the {chi}{sup 2} minima over a large grid of parameters, I argue that the main strength of this method is for events with the signals of multiple planets, where a much higher dimensional parameter space must be explored to find the correct light curve model.

Bennett, David P., E-mail: bennett@nd.ed [University of Notre Dame, Department of Physics, Notre Dame, IN 46556 (United States)

2010-06-20T23:59:59.000Z

348

Short ensembles: An Efficient Method for Discerning Climate-relevant Sensitivities in Atmospheric General Circulation Models  

SciTech Connect (OSTI)

This paper explores the feasibility of an experimentation strategy for investigating sensitivities in fast components of atmospheric general circulation models. The basic idea is to replace the traditional serial-in-time long-term climate integrations by representative ensembles of shorter simulations. The key advantage of the proposed method lies in its efficiency: since fewer days of simulation are needed, the computational cost is less, and because individual realizations are independent and can be integrated simultaneously, the new dimension of parallelism can dramatically reduce the turnaround time in benchmark tests, sensitivities studies, and model tuning exercises. The strategy is not appropriate for exploring sensitivity of all model features, but it is very effective in many situations. Two examples are presented using the Community Atmosphere Model version 5. The first example demonstrates that the method is capable of characterizing the model cloud and precipitation sensitivity to time step length. A nudging technique is also applied to an additional set of simulations to help understand the contribution of physics-dynamics interaction to the detected time step sensitivity. In the second example, multiple empirical parameters related to cloud microphysics and aerosol lifecycle are perturbed simultaneously in order to explore which parameters have the largest impact on the simulated global mean top-of-atmosphere radiation balance. Results show that in both examples, short ensembles are able to correctly reproduce the main signals of model sensitivities revealed by traditional long-term climate simulations for fast processes in the climate system. The efficiency of the ensemble method makes it particularly useful for the development of high-resolution, costly and complex climate models.

Wan, Hui; Rasch, Philip J.; Zhang, Kai; Qian, Yun; Yan, Huiping; Zhao, Chun

2014-09-08T23:59:59.000Z

349

A multi-resolution method for climate system modeling: application of spherical centroidal Voronoi tessellations  

SciTech Connect (OSTI)

During the next decade and beyond, climate system models will be challenged to resolve scales and processes that are far beyond their current scope. Each climate system component has its prototypical example of an unresolved process that may strongly influence the global climate system, ranging from eddy activity within ocean models, to ice streams within ice sheet models, to surface hydrological processes within land system models, to cloud processes within atmosphere models. These new demands will almost certainly result in the develop of multiresolution schemes that are able, at least regionally, to faithfully simulate these fine-scale processes. Spherical centroidal Voronoi tessellations (SCVTs) offer one potential path toward the development of a robust, multiresolution climate system model components. SCVTs allow for the generation of high quality Voronoi diagrams and Delaunay triangulations through the use of an intuitive, user-defined density function. In each of the examples provided, this method results in high-quality meshes where the quality measures are guaranteed to improve as the number of nodes is increased. Real-world examples are developed for the Greenland ice sheet and the North Atlantic ocean. Idealized examples are developed for ocean–ice shelf interaction and for regional atmospheric modeling. In addition to defining, developing, and exhibiting SCVTs, we pair this mesh generation technique with a previously developed finite-volume method. Our numerical example is based on the nonlinear, shallow water equations spanning the entire surface of the sphere. This example is used to elucidate both the potential benefits of this multiresolution method and the challenges ahead.

Ringler, Todd [Los Alamos National Laboratory; Ju, Lili [University of South Carolina; Gunzburger, Max [Florida State University

2008-01-01T23:59:59.000Z

350

A Lattice Boltzmann Fictitious Domain Method for Modeling Red Blood Cell Deformation and Multiple-Cell Hydrodynamic Interactions in Flow  

SciTech Connect (OSTI)

To model red blood cell (RBC) deformation in flow, the recently developed LBM-DLM/FD method ([Shi and Lim, 2007)29], derived from the lattice Boltzmann method and the distributed Lagrange multiplier/fictitious domain methodthe fictitious domain method, is extended to employ the mesoscopic network model for simulations of red blood cell deformation. The flow is simulated by the lattice Boltzmann method with an external force, while the network model is used for modeling red blood cell deformation and the fluid-RBC interaction is enforced by the Lagrange multiplier. To validate parameters of the RBC network model, sThe stretching numerical tests on both coarse and fine meshes are performed and compared with the corresponding experimental data to validate the parameters of the RBC network model. In addition, RBC deformation in pipe flow and in shear flow is simulated, revealing the capacity of the current method for modeling RBC deformation in various flows.

Shi, Xing; Lin, Guang; Zou, Jianfeng; Fedosov, Dmitry A.

2013-07-20T23:59:59.000Z

351

Modeling and Evaluation of Geophysical Methods for Monitoring and Tracking CO2 Migration  

SciTech Connect (OSTI)

Geological sequestration has been proposed as a viable option for mitigating the vast amount of CO{sub 2} being released into the atmosphere daily. Test sites for CO{sub 2} injection have been appearing across the world to ascertain the feasibility of capturing and sequestering carbon dioxide. A major concern with full scale implementation is monitoring and verifying the permanence of injected CO{sub 2}. Geophysical methods, an exploration industry standard, are non-invasive imaging techniques that can be implemented to address that concern. Geophysical methods, seismic and electromagnetic, play a crucial role in monitoring the subsurface pre- and post-injection. Seismic techniques have been the most popular but electromagnetic methods are gaining interest. The primary goal of this project was to develop a new geophysical tool, a software program called GphyzCO2, to investigate the implementation of geophysical monitoring for detecting injected CO{sub 2} at test sites. The GphyzCO2 software consists of interconnected programs that encompass well logging, seismic, and electromagnetic methods. The software enables users to design and execute 3D surface-to-surface (conventional surface seismic) and borehole-to-borehole (cross-hole seismic and electromagnetic methods) numerical modeling surveys. The generalized flow of the program begins with building a complex 3D subsurface geological model, assigning properties to the models that mimic a potential CO{sub 2} injection site, numerically forward model a geophysical survey, and analyze the results. A test site located in Warren County, Ohio was selected as the test site for the full implementation of GphyzCO2. Specific interest was placed on a potential reservoir target, the Mount Simon Sandstone, and cap rock, the Eau Claire Formation. Analysis of the test site included well log data, physical property measurements (porosity), core sample resistivity measurements, calculating electrical permittivity values, seismic data collection, and seismic interpretation. The data was input into GphyzCO2 to demonstrate a full implementation of the software capabilities. Part of the implementation investigated the limits of using geophysical methods to monitor CO{sub 2} injection sites. The results show that cross-hole EM numerical surveys are limited to under 100 meter borehole separation. Those results were utilized in executing numerical EM surveys that contain hypothetical CO{sub 2} injections. The outcome of the forward modeling shows that EM methods can detect the presence of CO{sub 2}.

Daniels, Jeff

2012-11-30T23:59:59.000Z

352

Numerical Modeling of Fracture Permeability Change in Naturally Fractured Reservoirs Using a Fully Coupled Displacement Discontinuity Method.  

E-Print Network [OSTI]

finite difference method to solve the fluid flow in fractures, a fully coupled displacement discontinuity method to build the global relation of fracture deformation, and the Barton-Bandis model of fracture deformation to build the local relation...

Tao, Qingfeng

2010-07-14T23:59:59.000Z

353

Multi-scale investigation of sheared flows in magnetized plasmas  

SciTech Connect (OSTI)

Flows parallel and perpendicular to magnetic fields in a plasma are important phenomena in many areas of plasma science research. The presence of these spatially inhomogeneous flows is often associated with the stability of the plasma. In fusion plasmas, these sheared flows can be stabilizing while in space plasmas, these sheared flows can be destabilizing. Because of this, there is broad interest in understanding the coupling between plasma stability and plasma flows. This research project has engaged in a study of the plasma response to spatially inhomogeneous plasma flows using three different experimental devices: the Auburn Linear Experiment for Instability Studies (ALEXIS) and the Compact Toroidal Hybrid (CTH) stellarator devices at Auburn University, and the Space Plasma Simulation Chamber (SPSC) at the Naval Research Laboratory. This work has shown that there is a commonality of the plasma response to sheared flows across a wide range of plasma parameters and magnetic field geometries. The goal of this multi-device, multi-scale project is to understand how sheared flows established by the same underlying physical mechanisms lead to different plasma responses in fusion, laboratory, and space plasmas.

Thomas, Jr., Dr. Edward

2014-09-19T23:59:59.000Z

354

Computational method and system for modeling, analyzing, and optimizing DNA amplification and synthesis  

DOE Patents [OSTI]

A computational method and computer-based system of modeling DNA synthesis for the design and interpretation of PCR amplification, parallel DNA synthesis, and microarray chip analysis. The method and system include modules that address the bioinformatics, kinetics, and thermodynamics of DNA amplification and synthesis. Specifically, the steps of DNA selection, as well as the kinetics and thermodynamics of DNA hybridization and extensions, are addressed, which enable the optimization of the processing and the prediction of the products as a function of DNA sequence, mixing protocol, time, temperature and concentration of species.

Vandersall, Jennifer A.; Gardner, Shea N.; Clague, David S.

2010-05-04T23:59:59.000Z

355

Performance of corrosion inhibiting admixtures for structural concrete -- assessment methods and predictive modeling  

SciTech Connect (OSTI)

During the past fifteen years corrosion inhibiting admixtures (CIAs) have become increasingly popular for protection of reinforced components of highway bridges and other structures from damage induced by chlorides. However, there remains considerable debate about the benefits of CIAs in concrete. A variety of testing methods to assess the performance of CIA have been reported in the literature, ranging from tests in simulated pore solutions to long-term exposures of concrete slabs. The paper reviews the published techniques and recommends the methods which would make up a comprehensive CIA effectiveness testing program. The results of this set of tests would provide the data which can be used to rank the presently commercially available CIA and future candidate formulations utilizing a proposed predictive model. The model is based on relatively short-term laboratory testing and considers several phases of a service life of a structure (corrosion initiation, corrosion propagation without damage, and damage to the structure).

Yunovich, M.; Thompson, N.G. [CC Technologies Labs., Inc., Dublin, OH (United States)

1998-12-31T23:59:59.000Z

356

An efficient modeling method for thermal stratification simulation in a BWR suppression pool  

SciTech Connect (OSTI)

The suppression pool in a BWR plant not only is the major heat sink within the containment system, but also provides major emergency cooling water for the reactor core. In several accident scenarios, such as LOCA and extended station blackout, thermal stratification tends to form in the pool after the initial rapid venting stage. Accurately predicting the pool stratification phenomenon is important because it affects the peak containment pressure; and the pool temperature distribution also affects the NPSHa (Available Net Positive Suction Head) and therefore the performance of the pump which draws cooling water back to the core. Current safety analysis codes use 0-D lumped parameter methods to calculate the energy and mass balance in the pool and therefore have large uncertainty in prediction of scenarios in which stratification and mixing are important. While 3-D CFD methods can be used to analyze realistic 3D configurations, these methods normally require very fine grid resolution to resolve thin substructures such as jets and wall boundaries, therefore long simulation time. For mixing in stably stratified large enclosures, the BMIX++ code has been developed to implement a highly efficient analysis method for stratification where the ambient fluid volume is represented by 1-D transient partial differential equations and substructures such as free or wall jets are modeled with 1-D integral models. This allows very large reductions in computational effort compared to 3-D CFD modeling. The POOLEX experiments at Finland, which was designed to study phenomena relevant to Nordic design BWR suppression pool including thermal stratification and mixing, are used for validation. GOTHIC lumped parameter models are used to obtain boundary conditions for BMIX++ code and CFD simulations. Comparison between the BMIX++, GOTHIC, and CFD calculations against the POOLEX experimental data is discussed in detail.

Haihua Zhao; Ling Zou; Hongbin Zhang; Hua Li; Walter Villanueva; Pavel Kudinov

2012-09-01T23:59:59.000Z

357

A Novel method for modeling the recoil in W boson events at hadron collider  

SciTech Connect (OSTI)

We present a new method for modeling the hadronic recoil in W {yields} {ell}{nu} events produced at hadron colliders. The recoil is chosen from a library of recoils in Z {yields} {ell}{ell} data events and overlaid on a simulated W {yields} {ell}{nu} event. Implementation of this method requires that the data recoil library describe the properties of the measured recoil as a function of the true, rather than the measured, transverse momentum of the boson. We address this issue using a multidimensional Bayesian unfolding technique. We estimate the statistical and systematic uncertainties from this method for the W boson mass and width measurements assuming 1 fb{sup -1} of data from the Fermilab Tevatron. The uncertainties are found to be small and comparable to those of a more traditional parameterized recoil model. For the high precision measurements that will be possible with data from Run II of the Fermilab Tevatron and from the CERN LHC, the method presented in this paper may be advantageous, since it does not require an understanding of the measured recoil from first principles.

Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; /Oklahoma U.; Abolins, Maris A.; /Michigan State U.; Acharya, Bannanje Sripath; /Tata Inst.; Adams, Mark Raymond; /Illinois U., Chicago; Adams, Todd; /Florida State U.; Aguilo, Ernest; /Alberta U. /Simon Fraser U. /York U., Canada /McGill U.; Ahsan, Mahsana; /Kansas State U.; Alexeev, Guennadi D.; /Dubna, JINR; Alkhazov, Georgiy D.; /St. Petersburg, INP; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls /Northeastern U.

2009-07-01T23:59:59.000Z

358

Application of the Maximum Entropy Method to the (2+1)d Four-Fermion Model  

E-Print Network [OSTI]

We investigate spectral functions extracted using the Maximum Entropy Method from correlators measured in lattice simulations of the (2+1)-dimensional four-fermion model. This model is particularly interesting because it has both a chirally broken phase with a rich spectrum of mesonic bound states and a symmetric phase where there are only resonances. In the broken phase we study the elementary fermion, pion, sigma and massive pseudoscalar meson; our results confirm the Goldstone nature of the pi and permit an estimate of the meson binding energy. We have, however, seen no signal of sigma -> pi pi decay as the chiral limit is approached. In the symmetric phase we observe a resonance of non-zero width in qualitative agreement with analytic expectations; in addition the ultra-violet behaviour of the spectral functions is consistent with the large non-perturbative anomalous dimension for fermion composite operators expected in this model.

C. R. Allton; J. E. Clowser; S. J. Hands; J. B. Kogut; C. G. Strouthos

2002-08-19T23:59:59.000Z

359

An adaptive wavelet stochastic collocation method for irregular solutions of stochastic partial differential equations  

SciTech Connect (OSTI)

Accurate predictive simulations of complex real world applications require numerical approximations to first, oppose the curse of dimensionality and second, converge quickly in the presence of steep gradients, sharp transitions, bifurcations or finite discontinuities in high-dimensional parameter spaces. In this paper we present a novel multi-dimensional multi-resolution adaptive (MdMrA) sparse grid stochastic collocation method, that utilizes hierarchical multiscale piecewise Riesz basis functions constructed from interpolating wavelets. The basis for our non-intrusive method forms a stable multiscale splitting and thus, optimal adaptation is achieved. Error estimates and numerical examples will used to compare the efficiency of the method with several other techniques.

Webster, Clayton G [ORNL; Zhang, Guannan [ORNL; Gunzburger, Max D [ORNL

2012-10-01T23:59:59.000Z

360

A RECOMMENDED PASQUILL-GIFFORD STABILITY CLASSIFICATION METHOD FOR SAFETY BASIS ATMOSPHERIC DISPERSION MODELING AT SRS  

SciTech Connect (OSTI)

Several of the most common methods for estimating Pasquill-Gifford (PG) stability (turbulence) class were evaluated for use in modeling the radiological consequences of SRS accidental releases using the MELCOR Accident Consequence Code System, Ver. 2 (MACCS2). Evaluation criteria included: (1) the ability of the method to represent diffusion characteristics above a predominantly forested landscape at SRS, (2) suitability of the method to provide data consistent with the formulation of the MACCS2 model, and (3) the availability of onsite meteorological data to support implementation of the method The evaluation resulted in a recommendation that PG stability classification for regulatory applications at SRS should be based on measurements of the standard deviation of the vertical component of wind direction fluctuations, {sigma}{sub e}, collected from the 61-m level of the SRS meteorological towers, and processed in full accordance with EPA-454/R-99-005 (EPA, 2000). This approach provides a direct measurement that is fundamental to diffusion and captures explicitly the turbulence generated by both mechanical and buoyant forces over the characteristic surface (forested) of SRS. Furthermore, due to the potentially significant enhancement of horizontal fluctuations in wind direction from the occurrence of meander at night, the use of {sigma}{sub e} will ensure a reasonably conservative estimate of PG stability class for use in dispersion models that base diffusion calculations on a single value of PG stability class. Furthermore, meteorological data bases used as input for MACCS2 calculations should contain hourly data for five consecutive annual periods from the most recent 10 years.

Hunter, C.

2012-03-28T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

Simulation of Thermal Stratification in BWR Suppression Pools with One Dimensional Modeling Method  

SciTech Connect (OSTI)

The suppression pool in a boiling water reactor (BWR) plant not only is the major heat sink within the containment system, but also provides the major emergency cooling water for the reactor core. In several accident scenarios, such as a loss-of-coolant accident and extended station blackout, thermal stratification tends to form in the pool after the initial rapid venting stage. Accurately predicting the pool stratification phenomenon is important because it affects the peak containment pressure; the pool temperature distribution also affects the NPSHa (available net positive suction head) and therefore the performance of the Emergency Core Cooling System and Reactor Core Isolation Cooling System pumps that draw cooling water back to the core. Current safety analysis codes use zero dimensional (0-D) lumped parameter models to calculate the energy and mass balance in the pool; therefore, they have large uncertainties in the prediction of scenarios in which stratification and mixing are important. While three-dimensional (3-D) computational fluid dynamics (CFD) methods can be used to analyze realistic 3-D configurations, these methods normally require very fine grid resolution to resolve thin substructures such as jets and wall boundaries, resulting in a long simulation time. For mixing in stably stratified large enclosures, the BMIX++ code (Berkeley mechanistic MIXing code in C++) has been developed to implement a highly efficient analysis method for stratification where the ambient fluid volume is represented by one-dimensional (1-D) transient partial differential equations and substructures (such as free or wall jets) are modeled with 1-D integral models. This allows very large reductions in computational effort compared to multi-dimensional CFD modeling. One heat-up experiment performed at the Finland POOLEX facility, which was designed to study phenomena relevant to Nordic design BWR suppression pool including thermal stratification and mixing, is used for validation. Comparisons between the BMIX++, GOTHIC, and CFD calculations against the POOLEX experimental data are discussed in detail.

Haihua Zhao; Ling Zou; Hongbin Zhang

2014-01-01T23:59:59.000Z

362

FATE Unified Modeling Method for Spent Nuclear Fuel and Sludge Processing, Shipping and Storage - 13405  

SciTech Connect (OSTI)

A unified modeling method applicable to the processing, shipping, and storage of spent nuclear fuel and sludge has been incrementally developed, validated, and applied over a period of about 15 years at the US DOE Hanford site. The software, FATE{sup TM}, provides a consistent framework for a wide dynamic range of common DOE and commercial fuel and waste applications. It has been used during the design phase, for safety and licensing calculations, and offers a graded approach to complex modeling problems encountered at DOE facilities and abroad (e.g., Sellafield). FATE has also been used for commercial power plant evaluations including reactor building fire modeling for fire PRA, evaluation of hydrogen release, transport, and flammability for post-Fukushima vulnerability assessment, and drying of commercial oxide fuel. FATE comprises an integrated set of models for fluid flow, aerosol and contamination release, transport, and deposition, thermal response including chemical reactions, and evaluation of fire and explosion hazards. It is one of few software tools that combine both source term and thermal-hydraulic capability. Practical examples are described below, with consideration of appropriate model complexity and validation. (authors)

Plys, Martin; Burelbach, James; Lee, Sung Jin; Apthorpe, Robert [Fauske and Associates, LLC, 16W070 83rd St., Burr Ridge, IL, 60527 (United States)] [Fauske and Associates, LLC, 16W070 83rd St., Burr Ridge, IL, 60527 (United States)

2013-07-01T23:59:59.000Z

363

A Method for Modeling Household Occupant Behavior to Simulate Residential Energy Consumption  

SciTech Connect (OSTI)

This paper presents a statistical method for modeling the behavior of household occupants to estimate residential energy consumption. Using data gathered by the U.S. Census Bureau in the American Time Use Survey (ATUS), actions carried out by survey respondents are categorized into ten distinct activities. These activities are defined to correspond to the major energy consuming loads commonly found within the residential sector. Next, time varying minute resolution Markov chain based statistical models of different occupant types are developed. Using these behavioral models, individual occupants are simulated to show how an occupant interacts with the major residential energy consuming loads throughout the day. From these simulations, the minimum number of occupants, and consequently the minimum number of multiple occupant households, needing to be simulated to produce a statistically accurate representation of aggregate residential behavior can be determined. Finally, future work will involve the use of these occupant models along side residential load models to produce a high-resolution energy consumption profile and estimate the potential for demand response from residential loads.

Johnson, Brandon J [ORNL] [ORNL; Starke, Michael R [ORNL] [ORNL; Abdelaziz, Omar [ORNL] [ORNL; Jackson, Roderick K [ORNL] [ORNL; Tolbert, Leon M [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK)

2014-01-01T23:59:59.000Z

364

Exploring the Latest Union2 SNIa Dataset by Using Model-Independent Parametrization Methods  

E-Print Network [OSTI]

We explore the cosmological consequences of the recently released Union2 sample of 557 Type Ia supernovae (SNIa). Combining this latest SNIa dataset with the Cosmic microwave background (CMB) anisotropy data from the Wilkinson Microwave Anisotropy Probe 7 year (WMAP7) observations and the baryon acoustic oscillation (BAO) results from the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7), we measure the dark energy density function $f(z)\\equiv \\rho_{de}(z)/\\rho_{de}(0)$ as a free function of redshift. Two model-independent parametrization methods (the binned parametrization and the polynomial interpolation parametrization) are used in this paper. By using the $\\chi^2$ statistic and the Bayesian information criterion, we find that the current observational data are still too limited to distinguish which parametrization method is better, and a simple model has advantage in fitting observational data than a complicated model. Moreover, it is found that all these parametrizations demonstrate that the Union2 dataset is still consistent with a cosmological constant at 1$\\sigma$ confidence level. Therefore, the Union2 dataset is different from the Constitution SNIa dataset, which more favors a dynamical dark energy.

Shuang Wang; Xiao-Dong Li; Miao Li

2011-01-04T23:59:59.000Z

365

A Stroke Severity Monitoring System Based on Quantitative Modified Multiscale Entropy  

E-Print Network [OSTI]

A Stroke Severity Monitoring System Based on Quantitative Modified Multiscale Entropy Wei-Jung Jou1, Taiwan (R.O.C) 2 Stroke center and Department of Neurology, National Taiwan University Hospital (NTUH, Taipei, Taiwan (R.O.C) Abstract Stroke is the leading cause of death and disability worldwide

Hung, Shih-Hao

366

Multi-scale mechanical improvement produced in carbon nanotube fibers by irradiation cross-linking  

E-Print Network [OSTI]

Review Multi-scale mechanical improvement produced in carbon nanotube fibers by irradiation cross T Fibers and yarns based on carbon nanotubes (CNT) are emerging as a possible improve- ment over more traditional high strength carbon fibers used as reinforcement elements in composite materials. This is driven

Espinosa, Horacio D.

367

A multi-scale bone study to estimate the risk of fracture related to osteoporosis  

E-Print Network [OSTI]

A multi-scale bone study to estimate the risk of fracture related to osteoporosis Abdelwahed' Orléans, 8, Rue Léonard de Vinci 45072 Orléans, France Objective: Osteoporosis is a disease marked. Bone fractures caused by the osteoporosis become increasingly important goal for both clinicians

Paris-Sud XI, Université de

368

SURFACE CLOUD RADIATIVE FORCING, CLOUD FRACTION AND CLOUD ALBEDO: THEIR RELATIONSHIP AND MULTISCALE VARIATION  

E-Print Network [OSTI]

SURFACE CLOUD RADIATIVE FORCING, CLOUD FRACTION AND CLOUD ALBEDO: THEIR RELATIONSHIP AND MULTISCALE/Atmospheric Sciences Division Brookhaven National Laboratory P.O. Box, Upton, NY www.bnl.gov ABSTRACT Cloud-induced climate change. Cloud-radiative forcing, cloud fraction, and cloud albedo are three key quantities

369

Atmospheric Mercury in the Great Lakes Region An Evaluation of the Community Multiscale Air Quality  

E-Print Network [OSTI]

Atmospheric Mercury in the Great Lakes Region An Evaluation of the Community Multiscale Air Quality Tracey Holloway #12;i Abstract Atmospheric mercury is a significant source for methylmercury (Me. In order to control MeHg exposures, policy-makers need a clear understanding of the atmospheric mercury

Wisconsin at Madison, University of

370

A Multiscale Study of High Performance Double-Walled Nanotube Polymer  

E-Print Network [OSTI]

- tinuous CNT yarns from CVD grown CNT aerogels.1,2,34 The stretching of the low den- sity aerogels of CNTs of randomly oriented bundles of DWNTs thinly coated with polymeric organic compounds. A multiscale in situ performance of yarns and isolated DWNT bundles with and without polymer coatings. DWNT polymer yarns exhibited

Espinosa, Horacio D.

371

3D multi-scale imaging of experimental fracture generation in shale gas reservoirs.  

E-Print Network [OSTI]

in research and shale unconventional reservoirs that will provide you with the skills to enter the oil and gas3D multi-scale imaging of experimental fracture generation in shale gas reservoirs. Supervisory-grained organic carbon-rich rocks (shales) are increasingly being targeted as shale gas "reservoirs". Due

Henderson, Gideon

372

Non-degenerate shell-model effective interactions from the Okamoto-Suzuki and Krenciglowa-Kuo iteration methods  

E-Print Network [OSTI]

We present calculations of shell-model effective interactions for both degenerate and non-degenerate model spaces using the Krenciglowa-Kuo (KK) and the extended Krenciglowa-Kuo iteration method recently developed by Okamoto, Suzuki {\\it et al.} (EKKO). The starting point is the low-momentum nucleon-nucleon interaction $V_{low-k}$ obtained from the N$^3$LO chiral two-nucleon interaction. The model spaces spanned by the $sd$ and $sdpf$ shells are both considered. With a solvable model, we show that both the KK and EKKO methods are convenient for deriving the effective interactions for non-degenerate model spaces. The EKKO method is especially desirable in this situation since the vertex function $\\hat Z$-box employed therein is well behaved while the corresponding vertex function $\\hat Q$-box employed in the Lee-Suzuki (LS) and KK methods may have singularities. The converged shell-model effective interactions given by the EKKO and KK methods are equivalent, although the former method is considerably more efficient. The degenerate $sd$-shell effective interactions given by the LS method are practically identical to those from the EKKO and KK methods. Results of the $sd$ one-shell and $sdpf$ two-shell calculations for $^{18}$O, $^{18}$F, $^{19}$O and $^{19}$F using the EKKO effective interactions are compared, and the importance of the shell-model three-nucleon forces is discussed.

Huan Dong; T. T. S. Kuo; J. W. Holt

2011-05-23T23:59:59.000Z

373

CP$^{N-1}$ model with the theta term and maximum entropy method  

E-Print Network [OSTI]

A $\\theta$ term in lattice field theory causes the sign problem in Monte Carlo simulations. This problem can be circumvented by Fourier-transforming the topological charge distribution $P(Q)$. This strategy, however, has a limitation, because errors of $P(Q)$ prevent one from calculating the partition function ${\\cal Z}(\\theta)$ properly for large volumes. This is called flattening. As an alternative approach to the Fourier method, we utilize the maximum entropy method (MEM) to calculate ${\\cal Z}(\\theta)$. We apply the MEM to Monte Carlo data of the CP$^3$ model. It is found that in the non-flattening case, the result of the MEM agrees with that of the Fourier transform, while in the flattening case, the MEM gives smooth ${\\cal Z}(\\theta)$.

Masahiro Imachi; Yasuhiko Shinno; Hiroshi Yoneyama

2004-09-25T23:59:59.000Z

374

A New Genetic Algorithm using Pareto Partitioning Method for Robust Partial Model Matching PID Design with Two Degrees of Freedom  

E-Print Network [OSTI]

A New Genetic Algorithm using Pareto Partitioning Method for Robust Partial Model Matching PID optimization, Partial model matching, PID controller with two degrees of freedom Abstract: In this paper we the design problem of the robust PID controller with two degrees of freedom based on the partial model

Coello, Carlos A. Coello

375

Long Gamma-Ray Bursts Calibrated by Pade Method and Constraints on Cosmological Models  

E-Print Network [OSTI]

Gamma-ray bursts (GRBs) are among the most powerful sources in the universe. In the recent years, GRBs have been proposed as a complementary probe to type Ia supernovae (SNIa). However, as is well known, there is a circularity problem in the use of GRBs to study cosmology. In this work, based on the Pad\\'e approximant, we propose a new cosmology-independent method to calibrate GRBs. We consider a sample consisting 138 long GRBs and obtain 79 calibrated long GRBs at high redshift $z>1.4$ (named Mayflower sample) which can be used to constrain cosmological models without the circularity problem. Then, we consider the constraints on several cosmological models with these 79 calibrated GRBs and other observational data. We show that GRBs are competent to be a complementary probe to the other well-established cosmological observations.

Liu, Jing

2014-01-01T23:59:59.000Z

376

Long Gamma-Ray Bursts Calibrated by Pade Method and Constraints on Cosmological Models  

E-Print Network [OSTI]

Gamma-ray bursts (GRBs) are among the most powerful sources in the universe. In the recent years, GRBs have been proposed as a complementary probe to type Ia supernovae (SNIa). However, as is well known, there is a circularity problem in the use of GRBs to study cosmology. In this work, based on the Pad\\'e approximant, we propose a new cosmology-independent method to calibrate GRBs. We consider a sample consisting 138 long GRBs and obtain 79 calibrated long GRBs at high redshift $z>1.4$ (named Mayflower sample) which can be used to constrain cosmological models without the circularity problem. Then, we consider the constraints on several cosmological models with these 79 calibrated GRBs and other observational data. We show that GRBs are competent to be a complementary probe to the other well-established cosmological observations.

Jing Liu; Hao Wei

2014-10-15T23:59:59.000Z

377

NEAMS FPL M2 Milestone Report: Development of a UO? Grain Size Model using Multicale Modeling and Simulation  

SciTech Connect (OSTI)

This report summarizes development work funded by the Nuclear Energy Advanced Modeling Simulation program's Fuels Product Line (FPL) to develop a mechanistic model for the average grain size in UO? fuel. The model is developed using a multiscale modeling and simulation approach involving atomistic simulations, as well as mesoscale simulations using INL's MARMOT code.

Tonks, Michael R. [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Zhang, Yongfeng [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Bai, Xianming [Idaho National Laboratory (INL), Idaho Falls, ID (United States)

2014-06-01T23:59:59.000Z

378

The Multi-Scale Mass Transfer Processes Controlling Natural Attenuation and Engineered Remediation: An IFC Focused on Hanford’s 300 Area Uranium Plume Quality Assurance Project Plan  

SciTech Connect (OSTI)

The purpose of the project is to conduct research at an Integrated Field-Scale Research Challenge Site in the Hanford Site 300 Area, CERCLA OU 300-FF-5 (Figure 1), to investigate multi-scale mass transfer processes associated with a subsurface uranium plume impacting both the vadose zone and groundwater. The project will investigate a series of science questions posed for research related to the effect of spatial heterogeneities, the importance of scale, coupled interactions between biogeochemical, hydrologic, and mass transfer processes, and measurements/approaches needed to characterize a mass-transfer dominated system. The research will be conducted by evaluating three (3) different hypotheses focused on multi-scale mass transfer processes in the vadose zone and groundwater, their influence on field-scale U(VI) biogeochemistry and transport, and their implications to natural systems and remediation. The project also includes goals to 1) provide relevant materials and field experimental opportunities for other ERSD researchers and 2) generate a lasting, accessible, and high-quality field experimental database that can be used by the scientific community for testing and validation of new conceptual and numerical models of subsurface reactive transport.

Fix, N. J.

2008-01-31T23:59:59.000Z

379

NUMERICAL MODELING OF CONTAMINANT TRANSPORT IN FRACTURED POROUS MEDIA USING MIXED FINITE ELEMENT AND FINITE VOLUME METHODS  

SciTech Connect (OSTI)

A mathematical model for contaminant species passing through fractured porous media is presented. In the numerical model, we combine two locally conservative methods, i.e. mixed finite element (MFE) and the finite volume methods. Adaptive triangle mesh is used for effective treatment of the fractures. A hybrid MFE method is employed to provide an accurate approximation of velocities field for both the fractures and matrix which are crucial to the convection part of the transport equation. The finite volume method and the standard MFE method are used to approximate the convection and dispersion terms respectively. The model is used to investigate the interaction of adsorption with transport and to extract information on effective adsorption distribution coefficients. Numerical examples in different fractured media illustrate the robustness and efficiency of the proposed numerical model.

Taylor, G.; Dong, C.; Sun, S.

2010-03-18T23:59:59.000Z

380

Combustion modeling of mono-carbon fuels using the rate-controlled constrained-equilibrium method  

SciTech Connect (OSTI)

The rate-controlled constrained-equilibrium (RCCE) method for simplifying the kinetics of complex reacting systems is reviewed. This method is based on the maximum entropy principle of thermodynamics and involves the assumption that the evolution of a system can be described using a relatively small set of slowly changing constraints imposed by the external and internal dynamics of the system. As a result, the number of differential and algebraic equations required to determine the constrained-equilibrium state of a system can be very much smaller than the number of species in the system. It follows that only reactions which change constraints are required to determine the dynamic evolution of the system and all other reactions are in equilibrium. The accuracy of the method depends on both the character and number of constraints employed and issues involved in the selection and transformation of the constraints are discussed. A method for determining the initial conditions for highly non-equilibrium systems is also presented. The method is illustrated by applying it to the oxidation of methane (CH{sub 4}), methanol (CH{sub 3}OH), and formaldehyde (CH{sub 2}O) in a constant volume adiabatic chamber over a wide range of initial temperatures, pressures, and equivalence ratios. The RCCE calculations were carried out using 8-12 constraints and 133 reactions. Good agreement with ''Detailed Kinetic Model'' (DMK) calculations using 29 species and 133 reactions was obtained. The number of reactions in the RCCE calculations could be reduced to 20 for CH{sub 4}, 16 for CH{sub 3}OH, and 12 for CH{sub 2}O without changing the results significantly affecting the agreement. It may be noted that a DKM with 29 species requires a minimum of 29 reactions. (author)

Janbozorgi, Mohammad; Ugarte, Sergio; Metghalchi, Hameed [Mechanical and Industrial Engineering Department, Northeastern University, Boston, MA 02115 (United States); Keck, James. C. [Mechanical Engineering Department, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

2009-10-15T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

Development of a Database to Support a Multi-Scale Analysis of the Distribution of Westslope Cutthroat Trout  

E-Print Network [OSTI]

Development of a Database to Support a Multi-Scale Analysis of the Distribution of Westslope ....................................................................................................................................5 Database Development expression of life history, and no hybridization) comprise only 22% of this total (Thurow et al. 1997

382

Multiscale Studies of the Formation and Stability of Surface-based Nanostructures, DOE Computational Materials Science Network - Final Report  

SciTech Connect (OSTI)

Summary of work performed under DOE-CMSN/FG0205ER46227, Multiscale Studies of the Formation and Stability of Surface-based Nanostructures, listing publications, collaborations, and presentations.

Einstein, Theodore L.

2011-10-31T23:59:59.000Z

383

New variational Monte Carlo method with an energy variance extrapolation for large-scale shell-model calculations  

E-Print Network [OSTI]

We propose a new variational Monte Carlo (VMC) method with an energy variance extrapolation for large-scale shell-model calculations. This variational Monte Carlo is a stochastic optimization method with a projected correlated condensed pair state as a trial wave function, and is formulated with the M-scheme representation of projection operators, the Pfaffian and the Markov-chain Monte Carlo (MCMC). Using this method, we can stochastically calculate approximated yrast energies and electro-magnetic transition strengths. Furthermore, by combining this VMC method with energy variance extrapolation, we can estimate exact shell-model energies.

Takahiro Mizusaki; Noritaka Shimizu

2012-01-27T23:59:59.000Z

384

EFFECTS OF PORE STRUCTURE CHANGE AND MULTI-SCALE HETEROGENEITY ON CONTAMINANT TRANSPORT AND REACTION RATE UPSCALING  

SciTech Connect (OSTI)

This project addressed the scaling of geochemical reactions to core and field scales, and the interrelationship between reaction rates and flow in porous media. We targeted reactive transport problems relevant to the Hanford site ? specifically the reaction of highly caustic, radioactive waste solutions with subsurface sediments, and the immobilization of 90Sr and 129I through mineral incorporation and passive flow blockage, respectively. We addressed the correlation of results for pore-scale fluid-soil interaction with field-scale fluid flow, with the specific goals of (i) predicting attenuation of radionuclide concentration; (ii) estimating changes in flow rates through changes of soil permeabilities; and (iii) estimating effective reaction rates. In supplemental work, we also simulated reactive transport systems relevant to geologic carbon sequestration. As a whole, this research generated a better understanding of reactive transport in porous media, and resulted in more accurate methods for reaction rate upscaling and improved prediction of permeability evolution. These scientific advancements will ultimately lead to better tools for management and remediation of DOE’s legacy waste problems. We established three key issues of reactive flow upscaling, and organized this project in three corresponding thrust areas. 1) Reactive flow experiments. The combination of mineral dissolution and precipitation alters pore network structure and the subsequent flow velocities, thereby creating a complex interaction between reaction and transport. To examine this phenomenon, we conducted controlled laboratory experimentation using reactive flow-through columns. ? Results and Key Findings: Four reactive column experiments (S1, S3, S4, S5) have been completed in which simulated tank waste leachage (STWL) was reacted with pure quartz sand, with and without Aluminum. The STWL is a caustic solution that dissolves quartz. Because Al is a necessary element in the formation of secondary mineral precipitates (cancrinite), conducting experiments under conditions with and without Al allowed us to experimentally separate the conditions that lead to quartz dissolution from the conditions that lead to quartz dissolution plus cancrinite precipitation. Consistent with our expectations, in the experiments without Al, there was a substantial reduction in volume of the solid matrix. With Al there was a net increase in the volume of the solid matrix. The rate and extent of reaction was found to increase with temperature. These results demonstrate a successful effort to identify conditions that lead to increases and conditions that lead to decreases in solid matrix volume due to reactions of caustic tank wastes with quartz sands. In addition, we have begun to work with slightly larger, intermediate-scale columns packed with Hanford natural sediments and quartz. Similar dissolution and precipitation were observed in these colums. The measurements are being interpreted with reactive transport modeling using STOMP; preliminary observations are reported here. 2) Multi-Scale Imaging and Analysis. Mineral dissolution and precipitation rates within a porous medium will be different in different pores due to natural heterogeneity and the heterogeneity that is created from the reactions themselves. We used a combination of X-ray computed microtomography, backscattered electron and energy dispersive X-ray spectroscopy combined with computational image analysis to quantify pore structure, mineral distribution, structure changes and fluid-air and fluid-grain interfaces. ? Results and Key Findings: Three of the columns from the reactive flow experiments at PNNL (S1, S3, S4) were imaged using 3D X-ray computed microtomography (XCMT) at BNL and analyzed using 3DMA-rock at SUNY Stony Brook. The imaging results support the mass balance findings reported by Dr. Um’s group, regarding the substantial dissolution of quartz in column S1. An important observation is that of grain movement accompanying dissolution in the unconsolidated media. The resultant movement

Lindquist, W. Brent; Jones, Keith W.; Um, Wooyong; Rockhold, mark; Peters, Catherine A.; Celia, Michael A.

2013-02-15T23:59:59.000Z

385

ISO-SWS calibration and the accurate modelling of cool-star atmospheres: I. Method  

E-Print Network [OSTI]

A detailed spectroscopic study of the ISO-SWS data of the red giant Alpha Tau is presented, which enables not only the accurate determination of the stellar parameters of Alpha Tau, but also serves as a critical review of the ISO-SWS calibration. This study is situated in a broader context of an iterative process in which both accurate observations of stellar templates and cool star atmosphere models are involved to improve the ISO-SWS calibration process as well as the theoretical modelling of stellar atmospheres. Therefore a sample of cool stars, covering the whole A0 -- M8 spectral classification, has been observed in order to disentangle calibration problems and problems in generating the theoretical models and corresponding synthetic spectrum. By using stellar parameters found in the literature large discrepancies were seen between the ISO-SWS data and the generated synthetic spectrum of Alpha Tau. A study of the influence of various stellar parameters on the theoretical models and synthetic spectra, in conjunction with the Kolmogorov-Smirnov test to evaluate objectively the goodness-of-fit, enables us to pin down the stellar parameters with a high accuracy: Teff = 3850 +/- 70 K, log g = 1.50 +/- 0.15, M = 2.3 +/- 0.8 Msun, z = -0.15 +/- 0.20 dex, microturbulence = 1.7 +/- 0.3 km/s, 12C/13C= 10 +/- 1, abundance of C = 8.35 +/- 0.20 dex, abundance of N= 8.35 +/- 0.25 dex, abundance of O = 8.83 +/- 0.15 dex and the angular diameter is 20.77 +/- 0.83 mas. These atmospheric parameters were then compared with the results provided by other authors using other methods and/or spectra.

L. Decin; C. Waelkens; K. Eriksson; B. Gustafsson; B. Plez; A. J. Sauval; W. Van Assche; B. Vandenbussche

2000-08-21T23:59:59.000Z

386

A partitioned-modeling procedure with a particle method for rock salt creep  

SciTech Connect (OSTI)

As observed from experiments, the transition between the secondary and tertiary stages of rock salt creep is characterized by localized damage, that is manifested by the formation and propagation of a boundary between localized and non-localized deformation fields. Because of the reduction in net load-carrying area under constant creep load, the creep damage will accelerate during the localization process and result in dynamic crack growth and final fracture during the tertiary stage. Due to the importance of localization phenomena in structural safety assessment, much research has been conducted to resolve experimental, theoretical and computational issues associated with localization problems, as reviewed recently by Chen and Schreyer. It has been found that the key component of various modeling approaches for localization is nothing but controlling the evolution of inhomogeneous interactions among material particles within a zone of finite dimension. In a continuum sense, however, the evolution process might be equally well characterized by the formation and propagation of a material surface discontinuity associated with a change of material properties. Hence, a partitioned-modeling approach has been proposed with the introduction of a moving material boundary for rate independent solids, and a set of moving jump forms of conservation laws have been used to define the moving boundary. To resolve localized large deformations and to predict the subsequent transition from continuous to discrete mechanisms, a particle method, combined with a dynamic relaxation scheme, is being modified to accommodate the partitioned-modeling approach. Preliminary results for rate-independent problems look very promising. In this presentation, the partitioned-modeling approach is applied to rate-dependent solids with an emphasis on the transition between the secondary and tertiary stages of rock salt creep.

Chen, Z.; Wang, M.L.; Zhou, S.J. [Univ. of New Mexico, Albuquerque, NM (United States)

1995-12-31T23:59:59.000Z

387

Application of the method of effective potentials to a model for twinning in elastic materials  

SciTech Connect (OSTI)

We extend the method of effective potentials to systems with next-nearest-neighbor interactions, and apply it to a one-dimensional discrete model for twins in elastic materials. The energy of the system is given by H = +(..gamma../2) (u/sub n//sub +1/-2u/sub n/+u/sub n-1/)/sup 2/ -cosu/sub n/, where the first two terms model the elastic strain-dependent energy which we take to be in the form of a double well in the strains and the third term gives its dependence on the discretized strain gradients. The periodic potential in the last term is introduced to allow for additional interactions with a background such as a parent phase, grain boundaries, or another array of twins. We obtain the phase diagram and show that it consists of various modulated commensurate as well as incommensurate ground-state configurations. We find continuous phonon-driven transitions between the homogeneous and any modulated phase, an incomplete devil's staircase in a narrow region close to the homogeneous phase and first-order soliton-driven transitions between commensurate phases. The first-order transition lines end at triple points where three commensurate phases coexist. In contrast to other nonconvex models we do not find here any superdegenerate points. We give general arguments which exclude the existence of such points in the present model. Preliminary results obtained by driving the system are discussed. These consist of various metastable configurations exhibiting strong hysteretic variation with the driving force.

Marianer, S.; Floria, L.M.

1988-12-01T23:59:59.000Z

388

Micro-macro models for viscoelastic fluids: modelling, mathematics and numerics  

E-Print Network [OSTI]

This paper is an introduction to the modelling of viscoelastic fluids, with an emphasis on micro-macro (or multiscale) models. Some elements of mathematical and numerical analysis are provided. These notes closely follow the lectures delivered by the second author at the Chinese Academy of Science during the Workshop "Stress Tensor Effects on Fluid Mechanics", in January 2010.

C. Le Bris; T. Lelièvre

2011-02-01T23:59:59.000Z

389

Model predictive control system and method for integrated gasification combined cycle power generation  

DOE Patents [OSTI]

Control system and method for controlling an integrated gasification combined cycle (IGCC) plant are provided. The system may include a controller coupled to a dynamic model of the plant to process a prediction of plant performance and determine a control strategy for the IGCC plant over a time horizon subject to plant constraints. The control strategy may include control functionality to meet a tracking objective and control functionality to meet an optimization objective. The control strategy may be configured to prioritize the tracking objective over the optimization objective based on a coordinate transformation, such as an orthogonal or quasi-orthogonal projection. A plurality of plant control knobs may be set in accordance with the control strategy to generate a sequence of coordinated multivariable control inputs to meet the tracking objective and the optimization objective subject to the prioritization resulting from the coordinate transformation.

Kumar, Aditya; Shi, Ruijie; Kumar, Rajeeva; Dokucu, Mustafa

2013-04-09T23:59:59.000Z

390

Modeling and Algorithmic Approaches to Constitutively-Complex, Microstructured Fluids  

SciTech Connect (OSTI)

We present a new multiscale model for complex uids based on three scales: microscopic, kinetic, and continuum. We choose the microscopic level as Kramers' bead-rod model for polymers, which we describe as a system of stochastic di#11;erential equations with an implicit constraint formulation. The associated Fokker-Planck equation is then derived, and adiabatic elimination removes the fast momentum coordinates. Approached in this way, the kinetic level reduces to a dispersive drift equation. The continuum level is modeled with a #12;nite volume Godunov-projection algorithm. We demonstrate computation of viscoelastic stress divergence using this multiscale approach.

Miller, Gregory H.; Forest, Gregory

2011-12-22T23:59:59.000Z

391

Implementation and Evaluation of the Virtual Fields Method: Determining Constitutive Model Parameters From Full-Field Deformation Data.  

SciTech Connect (OSTI)

The Virtual Fields Method (VFM) is an inverse method for constitutive model parameter identication that relies on full-eld experimental measurements of displacements. VFM is an alternative to standard approaches that require several experiments of simple geometries to calibrate a constitutive model. VFM is one of several techniques that use full-eld exper- imental data, including Finite Element Method Updating (FEMU) techniques, but VFM is computationally fast, not requiring iterative FEM analyses. This report describes the im- plementation and evaluation of VFM primarily for nite-deformation plasticity constitutive models. VFM was successfully implemented in MATLAB and evaluated using simulated FEM data that included representative experimental noise found in the Digital Image Cor- relation (DIC) optical technique that provides full-eld displacement measurements. VFM was able to identify constitutive model parameters for the BCJ plasticity model even in the presence of simulated DIC noise, demonstrating VFM as a viable alternative inverse method. Further research is required before VFM can be adopted as a standard method for constitu- tive model parameter identication, but this study is a foundation for ongoing research at Sandia for improving constitutive model calibration.

Kramer, Sharlotte Lorraine Bolyard; Scherzinger, William M.

2014-09-01T23:59:59.000Z

392

Investigating impacts of natural and human-induced environmental changes on hydrological processes and flood hazards using a GIS-based hydrological/hydraulic model and remote sensing data  

E-Print Network [OSTI]

a GISbased hydrological and hydraulic modeling system, which incorporates state-of-the-art remote sensing data to simulate flood under various scenarios. The conceptual framework and technical issues of incorporating multi-scale remote sensing data...

Wang, Lei

2009-06-02T23:59:59.000Z

393

REVIEW OF MECHANISTIC UNDERSTANDING AND MODELING AND UNCERTAINTY ANALYSIS METHODS FOR PREDICTING CEMENTITIOUS BARRIER PERFORMANCE  

SciTech Connect (OSTI)

Cementitious barriers for nuclear applications are one of the primary controls for preventing or limiting radionuclide release into the environment. At the present time, performance and risk assessments do not fully incorporate the effectiveness of engineered barriers because the processes that influence performance are coupled and complicated. Better understanding the behavior of cementitious barriers is necessary to evaluate and improve the design of materials and structures used for radioactive waste containment, life extension of current nuclear facilities, and design of future nuclear facilities, including those needed for nuclear fuel storage and processing, nuclear power production and waste management. The focus of the Cementitious Barriers Partnership (CBP) literature review is to document the current level of knowledge with respect to: (1) mechanisms and processes that directly influence the performance of cementitious materials (2) methodologies for modeling the performance of these mechanisms and processes and (3) approaches to addressing and quantifying uncertainties associated with performance predictions. This will serve as an important reference document for the professional community responsible for the design and performance assessment of cementitious materials in nuclear applications. This review also provides a multi-disciplinary foundation for identification, research, development and demonstration of improvements in conceptual understanding, measurements and performance modeling that would be lead to significant reductions in the uncertainties and improved confidence in the estimating the long-term performance of cementitious materials in nuclear applications. This report identifies: (1) technology gaps that may be filled by the CBP project and also (2) information and computational methods that are in currently being applied in related fields but have not yet been incorporated into performance assessments of cementitious barriers. The various chapters contain both a description of the mechanism or and a discussion of the current approaches to modeling the phenomena.

Langton, C.; Kosson, D.

2009-11-30T23:59:59.000Z

394

Sustainable Manufacturing via Multi-Scale, Physics-Based Process...  

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

modeling tools for enabling manufacturing-informed design. Graphic credit Third Wave Systems. accurate, easy-to-use, detailed physics- based process modeling tools to...

395

A summary of methods for approximating salt creep and disposal room closure in numerical models of multiphase flow  

SciTech Connect (OSTI)

Eight alternative methods for approximating salt creep and disposal room closure in a multiphase flow model of the Waste Isolation Pilot Plant (WIPP) were implemented and evaluated: Three fixed-room geometries three porosity functions and two fluid-phase-salt methods. The pressure-time-porosity line interpolation method is the method used in current WIPP Performance Assessment calculations. The room closure approximation methods were calibrated against a series of room closure simulations performed using a creep closure code, SANCHO. The fixed-room geometries did not incorporate a direct coupling between room void volume and room pressure. The two porosity function methods that utilized moles of gas as an independent parameter for closure coupling. The capillary backstress method was unable to accurately simulate conditions of re-closure of the room. Two methods were found to be accurate enough to approximate the effects of room closure; the boundary backstress method and pressure-time-porosity line interpolation. The boundary backstress method is a more reliable indicator of system behavior due to a theoretical basis for modeling salt deformation as a viscous process. It is a complex method and a detailed calibration process is required. The pressure lines method is thought to be less reliable because the results were skewed towards SANCHO results in simulations where the sequence of gas generation was significantly different from the SANCHO gas-generation rate histories used for closure calibration. This limitation in the pressure lines method is most pronounced at higher gas-generation rates and is relatively insignificant at lower gas-generation rates. Due to its relative simplicity, the pressure lines method is easier to implement in multiphase flow codes and simulations have a shorter execution time.

Freeze, G.A.; Larson, K.W. [INTERA, Inc., Albuquerque, NM (United States); Davies, P.B. [Sandia National Labs., Albuquerque, NM (United States)

1995-10-01T23:59:59.000Z

396

A Multi-Methods Approach to HRA and Human Performance Modeling: A Field Assessment  

SciTech Connect (OSTI)

The Advanced Test Reactor (ATR) is a research reactor at the Idaho National Laboratory is primarily designed and used to test materials to be used in other, larger-scale and prototype reactors. The reactor offers various specialized systems and allows certain experiments to be run at their own temperature and pressure. The ATR Canal temporarily stores completed experiments and used fuel. It also has facilities to conduct underwater operations such as experiment examination or removal. In reviewing the ATR safety basis, a number of concerns were identified involving the ATR canal. A brief study identified ergonomic issues involving the manual handling of fuel elements in the canal that may increase the probability of human error and possible unwanted acute physical outcomes to the operator. In response to this concern, that refined the previous HRA scoping analysis by determining the probability of the inadvertent exposure of a fuel element to the air during fuel movement and inspection was conducted. The HRA analysis employed the SPAR-H method and was supplemented by information gained from a detailed analysis of the fuel inspection and transfer tasks. This latter analysis included ergonomics, work cycles, task duration, and workload imposed by tool and workplace characteristics, personal protective clothing, and operational practices that have the potential to increase physical and mental workload. Part of this analysis consisted of NASA-TLX analyses, combined with operational sequence analysis, computational human performance analysis (CHPA), and 3D graphical modeling to determine task failures and precursors to such failures that have safety implications. Experience in applying multiple analysis techniques in support of HRA methods is discussed.

Jacques Hugo; David I Gertman

2012-06-01T23:59:59.000Z

397

Multiscale Methods for Fluid-Structure Interaction with Applications to Deformable Porous Media  

E-Print Network [OSTI]

12 3-Level Hierarchy of Macro-grids : : : : : : : : : : : : : : : : : : : : 81 13 Pressure 1 (triangle shading) and velocity w1 (vectors) plots for = 1=2, h = 1=12 for (a) x1 = 0; (b) x1 = 1; in the periodic reference con guration...-Structure Interaction problems. Theorem II.1. Let (v"; p") satisfy (2.2) in the slowly varying geometry F". Let (v0; v1) be as in (2.13a), (2.20) where (w; ) satisfy (2.14) and ( ; ) satisfy (2.18),(2.19). Let p0 be as in the Darcy velocity (cf. (2.17)). Then, we...

Brown, Donald

2012-10-19T23:59:59.000Z

398

VARIATIONAL MULTISCALE FINITE ELEMENT METHOD FOR FLOWS IN HIGHLY POROUS MEDIA  

E-Print Network [OSTI]

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

Lazarov, Raytcho

399

Adaptive Wavelet Methods for Saddle Point Problems \\Lambda Stephan Dahlke Reinhard Hochmuth Karsten Urban  

E-Print Network [OSTI]

multipliers. Keywords: Adaptive schemes, a posteriori error estimates, multiscale methods, wave­ lets, saddle of such equations, they still form a class of challenging problems. The indefinite \\Lambda The work of the first two the third author was a residence at the Istituto di Analisi Numerica del C.N.R. in Pavia, Italy. 1 #12; 2 S

400

Recommended Method To Account For Daughter Ingrowth For The Portsmouth On-Site Waste Disposal Facility Performance Assessment Modeling  

SciTech Connect (OSTI)

A 3-D STOMP model has been developed for the Portsmouth On-Site Waste Disposal Facility (OSWDF) at Site D as outlined in Appendix K of FBP 2013. This model projects the flow and transport of the following radionuclides to various points of assessments: Tc-99, U-234, U-235, U-236, U-238, Am-241, Np-237, Pu-238, Pu-239, Pu-240, Th-228, and Th-230. The model includes the radioactive decay of these parents, but does not include the associated daughter ingrowth because the STOMP model does not have the capability to model daughter ingrowth. The Savannah River National Laboratory (SRNL) provides herein a recommended method to account for daughter ingrowth in association with the Portsmouth OSWDF Performance Assessment (PA) modeling.

Phifer, Mark A.; Smith, Frank G. III

2013-06-21T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" from the National Library of EnergyBeta (NLEBeta).
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401

Multiscale analysis of nonlinear systems using computational homology  

SciTech Connect (OSTI)

This is a collaborative project between the principal investigators. However, as is to be expected, different PIs have greater focus on different aspects of the project. This report lists these major directions of research which were pursued during the funding period: (1) Computational Homology in Fluids - For the computational homology effort in thermal convection, the focus of the work during the first two years of the funding period included: (1) A clear demonstration that homology can sensitively detect the presence or absence of an important flow symmetry, (2) An investigation of homology as a probe for flow dynamics, and (3) The construction of a new convection apparatus for probing the effects of large-aspect-ratio. (2) Computational Homology in Cardiac Dynamics - We have initiated an effort to test the use of homology in characterizing data from both laboratory experiments and numerical simulations of arrhythmia in the heart. Recently, the use of high speed, high sensitivity digital imaging in conjunction with voltage sensitive fluorescent dyes has enabled researchers to visualize electrical activity on the surface of cardiac tissue, both in vitro and in vivo. (3) Magnetohydrodynamics - A new research direction is to use computational homology to analyze results of large scale simulations of 2D turbulence in the presence of magnetic fields. Such simulations are relevant to the dynamics of black hole accretion disks. The complex flow patterns from simulations exhibit strong qualitative changes as a function of magnetic field strength. Efforts to characterize the pattern changes using Fourier methods and wavelet analysis have been unsuccessful. (4) Granular Flow - two experts in the area of granular media are studying 2D model experiments of earthquake dynamics where the stress fields can be measured; these stress fields from complex patterns of 'force chains' that may be amenable to analysis using computational homology. (5) Microstructure Characterization - We extended our previous work on studying the time evolution of patterns associated with phase separation in conserved concentration fields. (6) Probabilistic Homology Validation - work on microstructure characterization is based on numerically studying the homology of certain sublevel sets of a function, whose evolution is described by deterministic or stochastic evolution equations. (7) Computational Homology and Dynamics - Topological methods can be used to rigorously describe the dynamics of nonlinear systems. We are approaching this problem from several perspectives and through a variety of systems. (8) Stress Networks in Polycrystals - we have characterized stress networks in polycrystals. This part of the project is aimed at developing homological metrics which can aid in distinguishing not only microstructures, but also derived mechanical response fields. (9) Microstructure-Controlled Drug Release - This part of the project is concerned with the development of topological metrics in the context of controlled drug delivery systems, such as drug-eluting stents. We are particularly interested in developing metrics which can be used to link the processing stage to the resulting microstructure, and ultimately to the achieved system response in terms of drug release profiles. (10) Microstructure of Fuel Cells - we have been using our computational homology software to analyze the topological structure of the void, metal and ceramic components of a Solid Oxide Fuel Cell.

Konstantin Mischaikow, Rutgers University /Georgia Institute of Technology, Michael Schatz, Georgia Institute of Technology, William Kalies, Florida Atlantic University, Thomas Wanner,George Mason University

2010-05-19T23:59:59.000Z

402

Multiscale analysis of nonlinear systems using computational homology  

SciTech Connect (OSTI)

This is a collaborative project between the principal investigators. However, as is to be expected, different PIs have greater focus on different aspects of the project. This report lists these major directions of research which were pursued during the funding period: (1) Computational Homology in Fluids - For the computational homology effort in thermal convection, the focus of the work during the first two years of the funding period included: (1) A clear demonstration that homology can sensitively detect the presence or absence of an important flow symmetry, (2) An investigation of homology as a probe for flow dynamics, and (3) The construction of a new convection apparatus for probing the effects of large-aspect-ratio. (2) Computational Homology in Cardiac Dynamics - We have initiated an effort to test the use of homology in characterizing data from both laboratory experiments and numerical simulations of arrhythmia in the heart. Recently, the use of high speed, high sensitivity digital imaging in conjunction with voltage sensitive fluorescent dyes has enabled researchers to visualize electrical activity on the surface of cardiac tissue, both in vitro and in vivo. (3) Magnetohydrodynamics - A new research direction is to use computational homology to analyze results of large scale simulations of 2D turbulence in the presence of magnetic fields. Such simulations are relevant to the dynamics of black hole accretion disks. The complex flow patterns from simulations exhibit strong qualitative changes as a function of magnetic field strength. Efforts to characterize the pattern changes using Fourier methods and wavelet analysis have been unsuccessful. (4) Granular Flow - two experts in the area of granular media are studying 2D model experiments of earthquake dynamics where the stress fields can be measured; these stress fields from complex patterns of 'force chains' that may be amenable to analysis using computational homology. (5) Microstructure Characterization - We extended our previous work on studying the time evolution of patterns associated with phase separation in conserved concentration fields. (6) Probabilistic Homology Validation - work on microstructure characterization is based on numerically studying the homology of certain sublevel sets of a function, whose evolution is described by deterministic or stochastic evolution equations. (7) Computational Homology and Dynamics - Topological methods can be used to rigorously describe the dynamics of nonlinear systems. We are approaching this problem from several perspectives and through a variety of systems. (8) Stress Networks in Polycrystals - we have characterized stress networks in polycrystals. This part of the project is aimed at developing homological metrics which can aid in distinguishing not only microstructures, but also derived mechanical response fields. (9) Microstructure-Controlled Drug Release - This part of the project is concerned with the development of topological metrics in the context of controlled drug delivery systems, such as drug-eluting stents. We are particularly interested in developing metrics which can be used to link the processing stage to the resulting microstructure, and ultimately to the achieved system response in terms of drug release profiles. (10) Microstructure of Fuel Cells - we have been using our computational homology software to analyze the topological structure of the void, metal and ceramic components of a Solid Oxide Fuel Cell.

Konstantin Mischaikow; Michael Schatz; William Kalies; Thomas Wanner

2010-05-24T23:59:59.000Z

403

Brief Guide to the MINC-Method for Modeling Flow and Transport in Fractured Media  

E-Print Network [OSTI]

and other methods for enhanced oil recovery from fracturedMINC to simulate enhanced oil recovery by steamflooding from

Pruess editor, K.

2010-01-01T23:59:59.000Z

404

A Method for Simulating Heat Recovery Systems Using AirModel in Implementations of the ASHRAE Simplified Energy Analysis Procedure  

E-Print Network [OSTI]

exchanger to verify the return air ratio. In this comparison, the recovered energy from the return air was equalized with the heat transfer of the heat exchanger model. An example of this methodology was used to simulate the HVAC system with a heat... to be measured for further investigation to verify the AirModel simulation. This method can be applied in Energy Plus and other simulation tools/software to simulate the building exhaust energy recovery. Acknowledgements The work of this paper...

Liu, C.; Zeig, M.; Claridge, D. E.; Wei, G.; Bruner, H.; Turner, W. D.

2005-01-01T23:59:59.000Z

405

Brinkmann Model and Double Penalization Method for the Flow Around a Porous Thin  

E-Print Network [OSTI]

the flow of a viscous fluid around a thin layer of porous material. Using a BKW method, we perform Keywords: Navier-Stokes equations, BKW method, penalization, porous ma- terial, thin layer. 1 Introduction . These asymptotic expansions are obtained with a BKW method. With these two asymptotic expansions, we will compare

Carbou, Gilles

406

Predictive Simulation and Design of Materials by Quasicontinuum and Accelerated Dynamics Methods  

SciTech Connect (OSTI)

This project developed the hyper-QC multiscale method to make possible the computation of previously inaccessible space and time scales for materials with thermally activated defects. The hyper-QC method combines the spatial coarse-graining feature of a finite temperature extension of the quasicontinuum (QC) method (aka “hot-QC”) with the accelerated dynamics feature of hyperdynamics. The hyper-QC method was developed, optimized, and tested from a rigorous mathematical foundation.

Luskin, Mitchell [University of Minnesota; James, Richard; Tadmor, Ellad

2014-03-30T23:59:59.000Z

407

Numerical Modeling of Hydraulic Fracture Propagation Using Thermo-hydro-mechanical Analysis with Brittle Damage Model by Finite Element Method  

E-Print Network [OSTI]

equation. Using a new moving-boundary element partition methodology (EPM), fracture propagation through heterogeneous media is predicted simply and efficiently. The method allows coupling fluid flow and rock deformation, and fracture propagation using...

Min, Kyoung

2013-07-16T23:59:59.000Z

408

Sustainable Manufacturing via Multi-Scale, Physics-Based Process...  

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

microstruc- Pasadena, CA tural modeling tools for metals that encounter severe plastic deformation. Georgia Institute of Technology Atlanta, GA * Enhancement of machining...

409

multiscale flow and transport in porous media - Department of ...  

E-Print Network [OSTI]

Multiphase ow and transport in heterogeneous porous media is typically ... we discuss two model problems: contaminant transport in aquifers and water ooding

410

Hydraulic Fractures: multiscale phenomena, asymptotic and numerical solutions  

E-Print Network [OSTI]

well stimulation Fracturing Fluid Proppant #12;5 Quarries #12;6 Magma flow Tarkastad #12;7 Model EQ 1

Peirce, Anthony

411

Evaluation of an approximate method for incorporating floating docks in harbor wave prediction models  

E-Print Network [OSTI]

coastal domains. However, floating structures such as floating breakwaters and docks are often encountered in the modeling domain. This makes the problem locally 3- dimensional. Hence it is problematic to incorporate a floating structure into the 2-d model...

Tang, Zhaoxiang

2005-11-01T23:59:59.000Z

412

Dynamic risk adjustment of prediction models using statistical process control methods  

E-Print Network [OSTI]

Introduction. Models that represent mathematical relationships between clinical outcomes and their predictors are useful to the decision making process in patient care. Many models, such as the score of neonatal physiology ...

Chuo, John, 1969-

2004-01-01T23:59:59.000Z

413

The Projection Operator Method and the Ashtekar-Horowitz-Boulware Model  

E-Print Network [OSTI]

Motivated by the recent work of Louko and Molgado, we consider the Ashtekar-Horowitz-Boulware model using the projection operator formalism. This paper uses the techniques developed in a recent paper of Klauder and Little to overcome the potential difficulties of this particular model. We also extend the model by including a larger class of functions than previously considered and evaluate the classical limit of the model.

J. Scott Little

2006-08-01T23:59:59.000Z

414

Efficient ray tracing algorithms based on wavefront construction and model based interpolation method  

E-Print Network [OSTI]

Analyses for Isotropic and Anisotropic Media . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 4.2.1 Isotropic Layers . . . . . . . . . . . . . . . . . . . 81 4.2.2 Anisotropic HTI Layers . . . . . . . . . . . . . . . 82 4.3 Multi-layer and Salt Dome... Models . . . . . . . . . . . . 88 4.3.1 3 Layer Model . . . . . . . . . . . . . . . . . . . . 93 4.3.2 Salt Dome Model . . . . . . . . . . . . . . . . . . 98 4.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . 103 V CONCLUSION...

Lee, Kyoung-Jin

2006-08-16T23:59:59.000Z

415

Mathematical Models and Methods in Applied Sciences Vol. 13, No. 12 (2003) 17671799  

E-Print Network [OSTI]

Scientific Publishing Company ON A DIFFUSIVELY CORRECTED KINEMATIC-WAVE TRAFFIC FLOW MODEL WITH CHANGING ROAD The classical Lighthill­Whitham­Richards (LWR) kinematic wave traffic flow model25,26,32 for unidirectional flow to x, and combine it with the diffusively corrected kinematic wave model (DCKWM) analyzed by Nelson,29

Karlsen, Kenneth Hvistendahl

416

Study of Multi-Scale Plant-Groundwater Interactions  

E-Print Network [OSTI]

equations developed may be used, with only minor adaptations, in a range of Earth system models. We adapted our system dynamics model to simulate the water uptake of the blue oaks at the Tonzi Ranch site. The shallow soil layer was divided into three soil...

Gou, Si

2014-05-30T23:59:59.000Z

417

An ignition and combustion model based on the level-set method for spark ignition engine multidimensional modeling  

SciTech Connect (OSTI)

To improve the prediction accuracy of the spark ignition and combustion processes in spark ignition engines, improved ignition and flame propagation models have been developed and implemented in the CFD code, KIVA-3V. An equation to calculate the spark ignition kernel growth rate is derived that considers the effects of the spark ignition discharge energy and flow turbulence on the ignition kernel growth. In addition, a flamelet combustion model based on the G equation combustion model was developed and implemented. To test the ignition and combustion models, they were applied to a homogeneous charge pancake-shaped-combustion-chamber engine, in which experimental heat flux data from probes in the engine head and cylinder liner were available. By comparing the flame arrival timings with the simulation predictions, the ignition and combustion models were validated. In addition, the models were also applied to a homogeneous charge propane-fueled SI engine. Good agreement with experimental cylinder pressures and NO{sub x} data was obtained as a function of ignition timing, engine speed, and EGR levels. (author)

Tan, Zhichao; Reitz, Rolf D. [Engine Research Center, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, WI 53706 (United States)

2006-04-15T23:59:59.000Z

418

SEISMIC AND ROCK PHYSICS DIAGNOSTICS OF MULTISCALE RESERVOIR TEXTURES  

SciTech Connect (OSTI)

As part of our study on ''Relationships between seismic properties and rock microstructure'', we have (1) Studied relationships between velocity and permeability. (2) Used independent experimental methods to measure the elastic moduli of clay minerals as functions of pressure and saturation. (3) Applied different statistical methods for characterizing heterogeneity and textures from scanning acoustic microscope (SAM) images of shale microstructures. (4) Analyzed the directional dependence of velocity and attenuation in different reservoir rocks (5) Compared Vp measured under hydrostatic and non-hydrostatic stress conditions in sands. (6) Studied stratification as a source of intrinsic anisotropy in sediments using Vp and statistical methods for characterizing textures in sands.

Gary Mavko

2003-10-01T23:59:59.000Z

419

Minimization of energy consumption in HVAC systems with data-driven models and an interior-point method  

E-Print Network [OSTI]

Minimization of energy consumption in HVAC systems with data-driven models and an interior online 13 June 2014 Keywords: HVAC Interior-point method Internal heat gain Multilayer perceptron-driven approach is applied to minimize energy consumption of a heating, ventilating, and air conditioning (HVAC

Kusiak, Andrew

420

A Survey of Procedural Methods for Terrain Modelling Ruben M. Smelik, Klaas Jan de Kraker and Saskia A. Groenewegen  

E-Print Network [OSTI]

such as terrain elevation and growth of plants in the 1980s and 1990s and extended its focus to urban environments or not at all. The integration and adjustment of existing procedural methods in such a way that they can Research (NWO) and the Netherlands ICT Research and Innovation Authority (ICT Regie). #12;current modelling

Bidarra, Rafael

Note: This page contains sample records for the topic "method multiscale modeling" 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

11.1 DEVELOPMENT OF AN IMMERSED BOUNDARY METHOD TO RESOLVE COMPLEX TERRAIN IN THE WEATHER RESEARCH AND FORECASTING MODEL  

E-Print Network [OSTI]

11.1 DEVELOPMENT OF AN IMMERSED BOUNDARY METHOD TO RESOLVE COMPLEX TERRAIN IN THE WEATHER RESEARCH AND FORECASTING MODEL Katherine A. Lundquist1 , Fotini K. Chow 2 , Julie K. Lundquist 3 , and Jeffery D. Mirocha 3 in urban areas are profoundly influenced by the presence of build- ings which divert mean flow, affect

Chow, Fotini Katopodes

422

A method for landscape analysis of forestry guidelines using bird habitat models and the Habplan harvest scheduler  

E-Print Network [OSTI]

A method for landscape analysis of forestry guidelines using bird habitat models and the Habplan guild richness and species probability of detection. Harvested wood volume provided a measure guidelines in commercial forest enterprises and improves upon the state of the art by utilizing an optimizing

Mitchell, Mike

423

Extrapolation methods for obtaining low-lying eigenvalues of a large-dimensional shell model Hamiltonian matrix  

SciTech Connect (OSTI)

We propose some new, efficient, and practical extrapolation methods to obtain a few low-lying eigenenergies of a large-dimensional Hamiltonian matrix in the nuclear shell model. We obtain those energies at the desired accuracy by extrapolation after diagonalizing small-dimensional submatrices of the sorted Hamiltonian matrix.

Yoshinaga, N. [Department of Physics, Saitama University, Saitama City 338-8570 (Japan); Arima, A. [Science Museum, Japan Science Foundation, 2-1 Kitanomaru-koen, Chiyoda ku, Tokyo 102-0091 (Japan)

2010-04-15T23:59:59.000Z

424

An Embedded Boundary Method for the Modeling of Unsteady Combustion in an Industrial GasFired Furnace \\Lambda  

E-Print Network [OSTI]

for the convective, viscous, and radiative heat transport terms in the mixed cells, while a finite element [20] which accounts for species diffusion, convective and radiative heat transfer, viscous transportAn Embedded Boundary Method for the Modeling of Unsteady Combustion in an Industrial Gas

425

Tumor Tracking Method Based on a Deformable 4D CT Breathing Motion Model Driven by an External Surface Surrogate  

SciTech Connect (OSTI)

Purpose: To develop a tumor tracking method based on a surrogate-driven motion model, which provides noninvasive dynamic localization of extracranial targets for the compensation of respiration-induced intrafraction motion in high-precision radiation therapy. Methods and Materials: The proposed approach is based on a patient-specific breathing motion model, derived a priori from 4-dimensional planning computed tomography (CT) images. Model parameters (respiratory baseline, amplitude, and phase) are retrieved and updated at each treatment fraction according to in-room radiography acquisition and optical surface imaging. The baseline parameter is adapted to the interfraction variations obtained from the daily cone beam (CB) CT scan. The respiratory amplitude and phase are extracted from an external breathing surrogate, estimated from the displacement of the patient thoracoabdominal surface, acquired with a noninvasive surface imaging device. The developed method was tested on a database of 7 lung cancer patients, including the synchronized information on internal and external respiratory motion during a CBCT scan. Results: About 30 seconds of simultaneous acquisition of CBCT and optical surface images were analyzed for each patient. The tumor trajectories identified in CBCT projections were used as reference and compared with the target trajectories estimated from surface displacement with the a priori motion model. The resulting absolute differences between the reference and estimated tumor motion along the 2 image dimensions ranged between 0.7 and 2.4 mm; the measured phase shifts did not exceed 7% of the breathing cycle length. Conclusions: We investigated a tumor tracking method that integrates breathing motion information provided by the 4-dimensional planning CT with surface imaging at the time of treatment, representing an alternative approach to point-based external–internal correlation models. Although an in-room radiograph-based assessment of the reliability of the motion model is envisaged, the developed technique does not involve the estimation and continuous update of correlation parameters, thus requiring a less intense use of invasive imaging.

Fassi, Aurora, E-mail: aurora.fassi@mail.polimi.it [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Schaerer, Joël; Fernandes, Mathieu [CREATIS, CNRS UMR 5220, INSERM U1044, Université Lyon 1, INSA-Lyon, Villeurbanne (France); Department of Radiotherapy, Centre Léon Bérard, Lyon (France); Riboldi, Marco [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Bioengineering Unit, CNAO Foundation, Pavia (Italy); Sarrut, David [CREATIS, CNRS UMR 5220, INSERM U1044, Université Lyon 1, INSA-Lyon, Villeurbanne (France); Department of Radiotherapy, Centre Léon Bérard, Lyon (France); Baroni, Guido [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Bioengineering Unit, CNAO Foundation, Pavia (Italy)

2014-01-01T23:59:59.000Z

426

Fault Modeling and Fault Type Distinguishing Test Methods for Digital Microfluidics Chips.  

E-Print Network [OSTI]

??Physical defects in digital microfludics chips (DMCs) can be very complicated and extremely difficult to find precise models, because each defect may occur anywhere. In… (more)

Sun, Xinyu

2013-01-01T23:59:59.000Z

427

Evaluation of multi-loop multi-scale integrals and phenomenological two-loop applications  

E-Print Network [OSTI]

In this thesis, major developments in the publicly available program SecDec are presented, extending the numerical evaluation of multi-loop multi-scale integrals from Euclidean to physical kinematics. The power of this new feature is shown in two phenomenological applications. In the first, numerical results for several massive two-loop four-point functions are shown. In its second application within this thesis, the leading momentum-dependent two-loop corrections to the neutral $\\mathcal{CP}$-even MSSM Higgs-boson masses are calculated. The results are included in the code FeynHiggs.

Sophia Borowka

2014-10-29T23:59:59.000Z

428

A multivariate quadrature based moment method for LES based modeling of supersonic combustion  

E-Print Network [OSTI]

function (PDF) approach is a powerful technique for large eddy simulation (LES) based modeling of scramjet and robust scramjet engine is critical for the1 realization of hypersonic flight. Availability of predictive computational models will provide2 a fast and efficient means for designing and optimizing scramjet engines

Raman, Venkat

429

A grid of MARCS model atmospheres for late-type stars I. Methods and general properties  

E-Print Network [OSTI]

We have constructed a grid of about 10,000 spherically symmetric and plane-parallel models with the MARCS program, and make it available for public use. Parameter ranges are: Teff=2500 to 8000 K, log g =log(GM/R2)= -1 to 5 (cgs) with various masses and radii, [Me/H]=-5 to +1, with [Alpha/Fe] = 0.0 and 0.4 and different choices of C and N abundances to also represent stars of types R, S and N, and with microturbulence parameters from 1 to 5 km/s. We also list fluxes in approximately 108,000 wavelength points. Underlying assumptions in addition to 1D stratification include hydrostatic equilibrium, MLT convection and LTE. A number of general properties of the models are discussed, in relation to the effects of changing blanketing and sphericity. Models are compared with other available grids and excellent agreement is found with plane-parallel models of Castelli and Kurucz within the overlapping parameter range. Although there are departures from the spherically symmetric NextGen models, the agreement with more recent PHOENIX models is gratifying. The models of the grid show regularities, but some interesting departures from general patterns occur for the coolest models due to the molecular opacities. We have tested rules of thumb concerning effects of blanketing and sphericity and found them to often be astonishingly accurate. Some interesting new phenomena have been discovered, such as the intricate coupling between blanketing and sphericity, and the strong effects of carbon enhancement on metal-poor models. We give further details of models and comparisons with observations in subsequent papers.

Bengt Gustafsson; Bengt Edvardsson; Kjell Eriksson; Uffe Graae Jorgensen; Aake Nordlund; Bertrand Plez

2008-05-05T23:59:59.000Z

430

SEISMIC AND ROCK PHYSICS DIAGNOSTICS OF MULTISCALE RESERVOIR TEXTURES  

SciTech Connect (OSTI)

As part of our study on ''Relationships between seismic properties and rock microstructure'', we have studied (1) Methods for detection of stress-induced velocity anisotropy in sands. (2) We have initiated efforts for velocity upscaling to quantify long-wavelength and short-wavelength velocity behavior and the scale-dependent dispersion caused by sediment variability in different depositional environments.

Gary Mavko

2003-06-30T23:59:59.000Z

431

Seismic and Rockphysics Diagnostics fo Multiscale Reservoir Textures  

SciTech Connect (OSTI)

We have continued to finish up our work on analyzing relationships between elastic properties and rock microstructure. We have worked on theoretical models for the effects of sorting and packing on elastic moduli and seismic velocities. After analyzing the scanning acoustic images of shales to quantify textures at different scales, we are now using theoretical inclusion models to quantify the elastic property variation with texture. In the closing phases of this project most of our efforts are now focused on writing up the results and preparing the final reports.

Gary Mavko

2005-02-01T23:59:59.000Z

432

Stochastic particle models and methods in risk analysis P. Del Moral (INRIA research team ALEA)  

E-Print Network [OSTI]

methods Ilustrations Security of offshore platforms in extreme see conditions Nuclear plant security efficiency, food risk analysis, bacterial propagations. System reliability : production chains, offshore, airport and flight collision risks. Nuclear plant security : radioactivity storage, nuclear tank cracks

Del Moral , Pierre

433

Simulation methods and tissue property models for non-invasive transcranial focused ultrasound surgery  

E-Print Network [OSTI]

Many brain tumors are localized deeply and are currently surgically inaccessible without causing severe damage to the overlying structures of the brain. The current spectrum of non-invasive methods for treating such tumors ...

Connor, Christopher W

2005-01-01T23:59:59.000Z

434

Modeling electrospinning process and a numerical scheme using Lattice Boltzmann method to simulate viscoelastic fluid flows  

E-Print Network [OSTI]

of secondary electric field on electrospinning process and whipping instability. It is observed that the external secondary field unwinds the jet spirals, reduces the whipping instability and increases the tension in the fiber. Lattice Boltzmann method (LBM...

Karra, Satish

2009-05-15T23:59:59.000Z

435

A Community Atmosphere Model with Superparameterized Clouds  

SciTech Connect (OSTI)

In 1999, National Center for Atmospheric Research (NCAR) scientists Wojciech Grabowski and Piotr Smolarkiewicz created a "multiscale" atmospheric model in which the physical processes associated with clouds were represented by running a simple high-resolution model within each grid column of a lowresolution global model. In idealized experiments, they found that the multiscale model produced promising simulations of organized tropical convection, which other models had struggled to produce. Inspired by their results, Colorado State University (CSU) scientists Marat Khairoutdinov and David Randall created a multiscale version of the Community Atmosphere Model (CAM). They removed the cloud parameterizations of the CAM, and replaced them with Khairoutdinov's high-resolution cloud model. They dubbed the embedded cloud model a "super-parameterization," and the modified CAM is now called the "SP-CAM." Over the next several years, many scientists, from many institutions, have explored the ability of the SP-CAM to simulate tropical weather systems, the day-night changes of precipitation, the Asian and African monsoons, and a number of other climate processes. Cristiana Stan of the Center for Ocean-Land-Atmosphere Interactions found that the SP-CAM gives improved results when coupled to an ocean model, and follow-on studies have explored the SP-CAM's utility when used as the atmospheric component of the Community Earth System Model. Much of this research has been performed under the auspices of the Center for Multiscale Modeling of Atmospheric Processes, a National Science Foundation (NSF) Science and Technology Center for which the lead institution is CSU.

Randall, David; Branson, Mark; Wang, Minghuai; Ghan, Steven J.; Craig, Cheryl; Gettelman, A.; Edwards, Jim

2013-06-18T23:59:59.000Z

436

A New Method for History Matching and Forecasting Shale Gas/Oil Reservoir Production Performance with Dual and Triple Porosity Models  

E-Print Network [OSTI]

Different methods have been proposed for history matching production of shale gas/oil wells which are drilled horizontally and usually hydraulically fractured with multiple stages. These methods are simulation, analytical models, and empirical...

Samandarli, Orkhan

2012-10-19T23:59:59.000Z

437

Application of Gaseous Sphere Injection Method for Modeling Under-expanded H2 Injection  

SciTech Connect (OSTI)

A methodology for modeling gaseous injection has been refined and applied to recent experimental data from the literature. This approach uses a discrete phase analogy to handle gaseous injection, allowing for addition of gaseous injection to a CFD grid without needing to resolve the injector nozzle. This paper focuses on model testing to provide the basis for simulation of hydrogen direct injected internal combustion engines. The model has been updated to be more applicable to full engine simulations, and shows good agreement with experiments for jet penetration and time-dependent axial mass fraction, while available radial mass fraction data is less well predicted.

Whitesides, R; Hessel, R P; Flowers, D L; Aceves, S M

2010-12-03T23:59:59.000Z

438

Shell Model Monte Carlo method in the $pn$-formalism and applications to the Zr and Mo isotopes  

E-Print Network [OSTI]

We report on the development of a new shell-model Monte Carlo algorithm which uses the proton-neutron formalism. Shell model Monte Carlo methods, within the isospin formulation, have been successfully used in large-scale shell-model calculations. Motivation for this work is to extend the feasibility of these methods to shell-model studies involving non-identical proton and neutron valence spaces. We show the viability of the new approach with some test results. Finally, we use a realistic nucleon-nucleon interaction in the model space described by (1p_1/2,0g_9/2) proton and (1d_5/2,2s_1/2,1d_3/2,0g_7/2,0h_11/2) neutron orbitals above the Sr-88 core to calculate ground-state energies, binding energies, B(E2) strengths, and to study pairing properties of the even-even 90-104 Zr and 92-106 Mo isotope chains.

C. Ozen; D. J. Dean

2005-08-05T23:59:59.000Z

439

Discovery of Novel Complex Metal Hydrides for Hydrogen Storage through Molecular Modeling and Combinatorial Methods  

SciTech Connect (OSTI)

UOP LLC, a Honeywell Company, Ford Motor Company, and Striatus, Inc., collaborated with Professor Craig Jensen of the University of Hawaii and Professor Vidvuds Ozolins of University of California, Los Angeles on a multi-year cost-shared program to discover novel complex metal hydrides for hydrogen storage. This innovative program combined sophisticated molecular modeling with high throughput combinatorial experiments to maximize the probability of identifying commercially relevant, economical hydrogen storage materials with broad application. A set of tools was developed to pursue the medium throughput (MT) and high throughput (HT) combinatorial exploratory investigation of novel complex metal hydrides for hydrogen storage. The assay programs consisted of monitoring hydrogen evolution as a function of temperature. This project also incorporated theoretical methods to help select candidate materials families for testing. The Virtual High Throughput Screening served as a virtual laboratory, calculating structures and their properties. First Principles calculations were applied to various systems to examine hydrogen storage reaction pathways and the associated thermodynamics. The experimental program began with the validation of the MT assay tool with NaAlH4/0.02 mole Ti, the state of the art hydrogen storage system given by decomposition of sodium alanate to sodium hydride, aluminum metal, and hydrogen. Once certified, a combinatorial 21-point study of the NaAlH4 â?? LiAlH4 â??Mg(AlH4)2 phase diagram was investigated with the MT assay. Stability proved to be a problem as many of the materials decomposed during synthesis, altering the expected assay results. This resulted in repeating the entire experiment with a mild milling approach, which only temporarily increased capacity. NaAlH4 was the best performer in both studies and no new mixed alanates were observed, a result consistent with the VHTS. Powder XRD suggested that the reverse reaction, the regeneration of the alanate from alkali hydride, Al and hydrogen, was hampering reversibility. The reverse reaction was then studied for the same phase diagram, starting with LiH, NaH, and MgH2, and Al. The study was extended to phase diagrams including KH and CaH2 as well. The observed hydrogen storage capacity in the Al hexahydrides was less than 4 wt. %, well short of DOE targets. The HT assay came on line and after certification with studies on NaAlH4, was first applied to the LiNH2 - LiBH4 - MgH2 phase diagram. The 60-point study elucidated trends within the system locating an optimum material of 0.6 LiNH2 â?? 0.3 MgH2 â?? 0.1 LiBH4 that stored about 4 wt. % H2 reversibly and operated below 220 °C. Also present was the phase Li4(NH2)3BH4, which had been discovered in the LiNH2 -LiBH4 system. This new ternary formulation performed much better than the well-known 2 LiNH2 â?? MgH2 system by 50 °C in the HT assay. The Li4(NH2)3BH4 is a low melting ionic liquid under our test conditions and facilitates the phase transformations required in the hydrogen storage reaction, which no longer relies on a higher energy solid state reaction pathway. Further study showed that the 0.6 LiNH2 â?? 0.3 MgH2 â?? 0.1 LiBH4 formulation was very stable with respect to ammonia and diborane desorption, the observed desorption was from hydrogen. This result could not have been anticipated and was made possible by the efficiency of HT combinatorial methods. Investigation of the analogous LiNH2 â?? LiBH4 â?? CaH2 phase diagram revealed new reversible hydrogen storage materials 0.625 LiBH4 + 0.375 CaH2 and 0.375 LiNH2 + 0.25 LiBH4 + 0.375 CaH2 operating at 1 wt. % reversible hydrogen below 175 °C. Powder x-ray diffraction revealed a new structure for the spent materials which had not been previously observed. While the storage capacity was not impressive, an important aspect is that it boron appears to participate in a low temperature reversible reaction. The last major area of study also focused

Lesch, David A; Adriaan Sachtler, J.W. J.; Low, John J; Jensen, Craig M; Ozolins, Vidvuds; Siegel, Don

2011-02-14T23:59:59.000Z

440

RELAP5/MOD3 code manual: Code structure, system models, and solution methods. Volume 1  

SciTech Connect (OSTI)

The RELAP5 code has been developed for best estimate transient simulation of light water reactor coolant systems during postulated accidents. The code models the coupled behavior of the reactor coolant system and the core for loss-of-coolant accidents, and operational transients, such as anticipated transient without scram, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling, approach is used that permits simulating a variety of thermal hydraulic systems. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater systems. RELAP5/MOD3 code documentation is divided into seven volumes: Volume I provides modeling theory and associated numerical schemes.

NONE

1995-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "method multiscale modeling" 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

On the rheological models used for time-domain methods of seismic wave propagation  

E-Print Network [OSTI]

January 2005. [1] After publications by Emmerich and Korn [1987] and Carcione et al. [1988a, 1988b rheological models ­ generalized Maxwell body (as defined by Emmerich and Korn) or generalized Zener body. Two

442

Discrete optimization methods to fit piecewise-affine models to data ...  

E-Print Network [OSTI]

Fitting a set of data points in Rn with a combination of low complexity mod- ... general problem of fitting a piecewise affine model to the data points {(a1,b1),..., ...

2015-03-09T23:59:59.000Z

443

Discrete optimization methods to fit piecewise-affine models to data ...  

E-Print Network [OSTI]

Mar 8, 2015 ... polimi.it). Abstract: Fitting piecewise affine models to data points is a pervasive task in many scientific disciplines. In this work, we address the k- ...

Edoardo Amaldi

2015-03-08T23:59:59.000Z

444

Fabrication of a SWATH vessel scale model for seakeeping tests using rapid prototyping methods  

E-Print Network [OSTI]

This paper describes the techniques used to fabricate a one meter long, 1/6 scale model of a Small Waterplane Area, Twin Hull (SWATH) Unmanned Surface Vehicle (USV) that will be used primarily for dynamic seakeeping testing ...

DiMino, John Robert

2013-01-01T23:59:59.000Z

445

Systems, methods and computer-readable media for modeling cell performance fade of rechargeable electrochemical devices  

DOE Patents [OSTI]

A system includes an electrochemical cell, monitoring hardware, and a computing system. The monitoring hardware periodically samples performance characteristics of the electrochemical cell. The computing system determines cell information from the performance characteristics of the electrochemical cell. The computing system also develops a mechanistic level model of the electrochemical cell to determine performance fade characteristics of the electrochemical cell and analyzing the mechanistic level model to estimate performance fade characteristics over aging of a similar electrochemical cell. The mechanistic level model uses first constant-current pulses applied to the electrochemical cell at a first aging period and at three or more current values bracketing a first exchange current density. The mechanistic level model also is based on second constant-current pulses applied to the electrochemical cell at a second aging period and at three or more current values bracketing the second exchange current density.

Gering, Kevin L

2013-08-27T23:59:59.000Z

446

k - Version of Finite Element Method for Polymer flows using Giesekus Constitutive Model  

E-Print Network [OSTI]

and hence high Deborah number flows are invariably associated with higher flow rates and thus higher velocities. In many standard model problems such as couette flow, lid driven cavity, expansion, contraction etc, severe deborah number (De) limitations...

Deshpande, Kedar M.

2008-01-31T23:59:59.000Z

447

New methods for estimation, modeling and validation of dynamical systems using automatic differentiation  

E-Print Network [OSTI]

equations, for a class of nonlinear dynamical systems. In the area of trajectory optimization some new ideas are presented for automating the process of deriving co- state differential equations. Additionally, higher-order algorithms for computing... midcourse corrections are introduced. In Chapter IV, some new insights into modeling of dynamical systems are presented. Producing dynamical models in the form of coupled nonlinear differential equations is a frequent first step for analysis, estimation...

Griffith, Daniel Todd

2005-02-17T23:59:59.000Z

448

Preprint -Proc. of MMM 07-09/01/2009, Sophia-Antipolis, France. Sparse Multiscale Patches (SMP)  

E-Print Network [OSTI]

Preprint - Proc. of MMM 07-09/01/2009, Sophia-Antipolis, France. Sparse Multiscale Patches (SMP) for image categorization Paolo Piro, Sandrine Anthoine, Eric Debreuve, and Michel Barlaud University of Nice-Sophia-09/01/2009, Sophia-Antipolis, France. image locations that are relevant to characterize the visual content. Local ap

Anthone, Sandrine

449

Creation of photo-modulated multi-state and multi-scale molecular assemblies via binary-state molecular switch  

E-Print Network [OSTI]

Creation of photo-modulated multi-state and multi-scale molecular assemblies via binaryth January 2010 DOI: 10.1039/b916721h The creation of photo-modulated multi-state and multi location; this becomes especially valuable in nanoscience and nanotechnology applications, such as sensor

Huang, Jianbin

450

MULTISCALE RESOURCE SELECTION OF RUFFED GROUSE IN THE BLACK HILLS NATIONAL FOREST OF SOUTH DAKOTA AND WYOMING  

E-Print Network [OSTI]

MULTISCALE RESOURCE SELECTION OF RUFFED GROUSE IN THE BLACK HILLS NATIONAL FOREST OF SOUTH DAKOTA) in the Black Hills National Forest (BHNF). Due to this status the U.S. Forest Service and the South Dakota and Parks, United States Forest Service Rocky Mountain Research Station, South Dakota State University

451

A Multi-Scale Analysis Scheme on Abelian Groups with an Application to Operators Dual to Hill's Equation  

E-Print Network [OSTI]

We present an abstract multiscale analysis scheme for matrix functions $(H_{\\varepsilon}(m,n))_{m,n\\in \\mathfrak{T}}$, where $\\mathfrak{T}$ is an Abelian group equipped with a distance $|\\cdot|$. This is an extension of the scheme developed by Damanik and Goldstein for the special case $\\mathfrak{T} = \\mathbb{Z}^\

David Damanik; Michael Goldstein; Milivoje Lukic

2014-09-28T23:59:59.000Z

452

Geographic Information Sciences Vol. 6, No. 1. pp.6-19 2000 Multiscale Analysis of Landscape Heterogeneity  

E-Print Network [OSTI]

Geographic Information Sciences Vol. 6, No. 1. pp.6-19 2000 1 Multiscale Analysis of Landscape 89557, USA Abstract A major goal of landscape ecology is to understand the formation, dynamics, and maintenance of spatial heterogeneity. Spatial heterogeneity is the most fundamental characteristic of all

Wu, Jianguo "Jingle"

453

Data-Adaptive Wavelets and Multi-Scale Singular Spectrum Analysis  

E-Print Network [OSTI]

Using multi-scale ideas from wavelet analysis, we extend singular-spectrum analysis (SSA) to the study of nonstationary time series of length $N$ whose intermittency can give rise to the divergence of their variance. SSA relies on the construction of the lag-covariance matrix C on M lagged copies of the time series over a fixed window width W to detect the regular part of the variability in that window in terms of the minimal number of oscillatory components; here W = M Dt, with Dt the time step. The proposed multi-scale SSA is a local SSA analysis within a moving window of width M fractal or power-law behavior which mimic selected features of certain climatic and geophysical time series. A real application is to the Southern Oscillation index (SOI) monthly values for 1933-1996. Our methodology highlights an abrupt periodicity shift in the SOI near 1960. This abrupt shift between 4 and 3 years supports the Devil's staircase scenario for the El Nino/Southern Oscillation phenomenon.

P. Yiou; D. Sornette; M. Ghil

1998-10-29T23:59:59.000Z

454

Natural Tracers and Multi-Scale Assessment of Caprock Sealing Behavior: A Case Study of the Kirtland Formation, San Juan Basin  

SciTech Connect (OSTI)

The assessment of caprocks for geologic CO{sub 2} storage is a multi-scale endeavor. Investigation of a regional caprock - the Kirtland Formation, San Juan Basin, USA - at the pore-network scale indicates high capillary sealing capacity and low permeabilities. Core and wellscale data, however, indicate a potential seal bypass system as evidenced by multiple mineralized fractures and methane gas saturations within the caprock. Our interpretation of {sup 4}He concentrations, measured at the top and bottom of the caprock, suggests low fluid fluxes through the caprock: (1) Of the total {sup 4}He produced in situ (i.e., at the locations of sampling) by uranium and thorium decay since deposition of the Kirtland Formation, a large portion still resides in the pore fluids. (2) Simple advection-only and advection-diffusion models, using the measured {sup 4}He concentrations, indicate low permeability ({approx}10-20 m{sup 2} or lower) for the thickness of the Kirtland Formation. These findings, however, do not guarantee the lack of a large-scale bypass system. The measured data, located near the boundary conditions of the models (i.e., the overlying and underlying aquifers), limit our testing of conceptual models and the sensitivity of model parameterization. Thus, we suggest approaches for future studies to better assess the presence or lack of a seal bypass system at this particular site and for other sites in general.

Jason Heath; Brian McPherson; Thomas Dewers

2011-03-15T23:59:59.000Z

455

Modeling green fluorescent protein transcription, translation and modification as a method to obtain NF-kappaB activation profiles  

E-Print Network [OSTI]

Jayaraman Committee Members, Juergen Hahn Mike McShane Head of Department, N.K. Anand August 2007 Major Subject: Chemical Engineering iii ABSTRACT Modeling Green Fluorescent Protein Transcription, Translation and Modification as a Method... my profound thanks to my advisor, Dr. Arul Jayaraman, and my committee members, Dr. Juergen Hahn and Dr. Mike McShane, for their guidance and support throughout the course of this research. I would like to extend my gratitude to Jacky Huang who...

Laible, Allyson Marie

2009-05-15T23:59:59.000Z

456

Selection of Polynomial Chaos Bases via Bayesian Model Uncertainty Methods with Applications to Sparse Approximation of PDEs with Stochastic Inputs  

SciTech Connect (OSTI)

Generalized polynomial chaos (gPC) expansions allow the representation of the solution of a stochastic system as a series of polynomial terms. The number of gPC terms increases dramatically with the dimension of the random input variables. When the number of the gPC terms is larger than that of the available samples, a scenario that often occurs if the evaluations of the system are expensive, the evaluation of the gPC expansion can be inaccurate due to over-fitting. We propose a fully Bayesian approach that allows for global recovery of the stochastic solution, both in spacial and random domains, by coupling Bayesian model uncertainty and regularization regression methods. It allows the evaluation of the PC coefficients on a grid of spacial points via (1) Bayesian model average or (2) medial probability model, and their construction as functions on the spacial domain via spline interpolation. The former accounts the model uncertainty and provides Bayes-optimal predictions; while the latter, additionally, provides a sparse representation of the solution by evaluating the expansion on a subset of dominating gPC bases when represented as a gPC expansion. Moreover, the method quantifies the importance of the gPC bases through inclusion probabilities. We design an MCMC sampler that evaluates all the unknown quantities without the need of ad-hoc techniques. The proposed method is suitable for, but not restricted to, problems whose stochastic solution is sparse at the stochastic level with respect to the gPC bases while the deterministic solver involved is expensive. We demonstrate the good performance of the proposed method and make comparisons with others on 1D, 14D and 40D in random space elliptic stochastic partial differential equations.

Karagiannis, Georgios; Lin, Guang

2014-02-15T23:59:59.000Z

457

Selection of polynomial chaos bases via Bayesian model uncertainty methods with applications to sparse approximation of PDEs with stochastic inputs  

SciTech Connect (OSTI)

Generalized polynomial chaos (gPC) expansions allow us to represent the solution of a stochastic system using a series of polynomial chaos basis functions. The number of gPC terms increases dramatically as the dimension of the random input variables increases. When the number of the gPC terms is larger than that of the available samples, a scenario that often occurs when the corresponding deterministic solver is computationally expensive, evaluation of the gPC expansion can be inaccurate due to over-fitting. We propose a fully Bayesian approach that allows for global recovery of the stochastic solutions, in both spatial and random domains, by coupling Bayesian model uncertainty and regularization regression methods. It allows the evaluation of the PC coefficients on a grid of spatial points, via (1) the Bayesian model average (BMA) or (2) the median probability model, and their construction as spatial functions on the spatial domain via spline interpolation. The former accounts for the model uncertainty and provides Bayes-optimal predictions; while the latter provides a sparse representation of the stochastic solutions by evaluating the expansion on a subset of dominating gPC bases. Moreover, the proposed methods quantify the importance of the gPC bases in the probabilistic sense through inclusion probabilities. We design a Markov chain Monte Carlo (MCMC) sampler that evaluates all the unknown quantities without the need of ad-hoc techniques. The proposed methods are suitable for, but not restricted to, problems whose stochastic solutions are sparse in the stochastic space with respect to the gPC bases while the deterministic solver involved is expensive. We demonstrate the accuracy and performance of the proposed methods and make comparisons with other approaches on solving elliptic SPDEs with 1-, 14- and 40-random dimensions.

Karagiannis, Georgios, E-mail: georgios.karagiannis@pnnl.gov; Lin, Guang, E-mail: guang.lin@pnnl.gov

2014-02-15T23:59:59.000Z

458

Dakota uncertainty quantification methods applied to the NEK-5000 SAHEX model.  

SciTech Connect (OSTI)

This report summarizes the results of a NEAMS project focused on the use of uncertainty and sensitivity analysis methods within the NEK-5000 and Dakota software framework for assessing failure probabilities as part of probabilistic risk assessment. NEK-5000 is a software tool under development at Argonne National Laboratory to perform computational fluid dynamics calculations for applications such as thermohydraulics of nuclear reactor cores. Dakota is a software tool developed at Sandia National Laboratories containing optimization, sensitivity analysis, and uncertainty quantification algorithms. The goal of this work is to demonstrate the use of uncertainty quantification methods in Dakota with NEK-5000.

Weirs, V. Gregory

2014-03-01T23:59:59.000Z

459

Surrogate and reduced-order modeling: a comparison of  

E-Print Network [OSTI]

. Second, sam- pling may be complicated by the large dimensionality of the input space--as when the inputs or accelerating evaluations of a stochastic model for the data, and thus are also applicable in a frequentist and multiscale approaches, and stochastic spectral approaches. Second, the dimension of the input space can

Peraire, Jaime

460

Thermal Modeling, Analysis and Management in VLSI Circuits: Principles and Methods  

E-Print Network [OSTI]

is an active method that requires design overhead. With component packages becoming more compact and having have made thermal effects one of the most important concerns of VLSI designers. The increasing of the substrate and metal line temperatures on the reliability and performance of the devices and interconnections

Pedram, Massoud

Note: This page contains sample records for the topic "method multiscale modeling" 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

OPERATIONAL REMOTE SENSING METHODS TO DERIVE SNOW PROPERTIES FOR HYDROLOGICAL MODELLING  

E-Print Network [OSTI]

sensing methods to derive snow properties using both optical and SAR data are presented of NOAA- AVHRR data. Processing consists of calibration, geometric correction and classification including. In order to derive snow properties from SAR, radiometric and geometric correction tools for ERS were

Oldenburg, Carl von Ossietzky Universität

462

Complete direct method for electron-hydrogen scattering: Application to the collinear and Temkin-Poet models  

SciTech Connect (OSTI)

We present an efficient generalization of the exterior complex scaling (ECS) method to extract discrete inelastic and ionization amplitudes for electron-impact scattering of atomic hydrogen. This fully quantal method is demonstrated over a range of energies for the collinear and Temkin-Poet models and near-threshold ionization is examined in detail for singlet and triplet scattering. Our numerical calculations for total ionization cross sections near threshold strongly support the classical threshold law of Wannier [Phys. Rev. 90, 817 (1953)] ({sigma}{proportional_to}E{sup 1.128{+-}}{sup 0.004}) for the L=0 singlet collinear model and the semiclassical threshold law of Peterkop [J. Phys. B 16, L587 (1983)] ({sigma}{proportional_to}E{sup 3.37{+-}}{sup 0.02}) for the L=0 triplet collinear model, and are consistent with the semiclassical threshold law of Macek and Ihra [Phys. Rev. A 55, 2024 (1997)] ({sigma}{proportional_to}exp[(-6.87{+-}0.01)E{sup -1/6}]) for the singlet Temkin-Poet model.

Bartlett, Philip L.; Stelbovics, Andris T. [Centre for Atomic, Molecular and Surface Physics, Murdoch University, Perth 6150 (Australia)

2004-02-01T23:59:59.000Z

463

REACTIVE FLOW IN VUGGY CARBONATES: METHODS AND MODELS APPLIED TO MATRIX ACIDIZING OF CARBONATES  

E-Print Network [OSTI]

and its effect on fluid flow is numerical simulation. A 3D finite difference numerical model is developed based on Darcy-Brinkman formulation (DBF). Using the developed simulator a flow-based inversion approach is implemented to understand the connectivity...

Izgec, Omer

2010-07-14T23:59:59.000Z

464

Nonlinear Model Based Coordinated Adaptive Robust Control of Electro-hydraulic Robotic Arms via Overparametrizing Method  

E-Print Network [OSTI]

Nonlinear Model Based Coordinated Adaptive Robust Control of Electro-hydraulic Robotic Arms via by electrical motors, hydraulic robot arms have a richer nonlinear dynam- ics and stronger couplings among uncertainties only. Simulation and experimental results on a three degree-of-freedom (DOF) hydraulic robot arm

Yao, Bin

465

DAILY FLOW ROUTING WITH THE MUSKINGUM-CUNGE METHOD IN THE PECOS RIVER RIVERWARE MODEL  

E-Print Network [OSTI]

for the Pecos River water operations model to simulate flood wave travel time (translation) and reduction to evaluate whether a kinematic or diffusive wave approximation to the full dynamic wave equation could.D., Research Associate, Center for Advanced Decision Support for Water and Environmental Systems, University

466

Contributions to Meta-Modeling Tools and Methods ISBN 91-85299-41-3  

E-Print Network [OSTI]

and simulators. This thesis presents several contributions towards this vision, in the context of the Modelica Modelica, which facilitates the development of tools for analysis, checking, querying, documentation, transformation and management of Modelica models. We have used XML Schema for the representation of the meta

Zhao, Yuxiao

467

Sensitivity of the Properties of Ruthenium “Blue Dimer” to Method, Basis Set, and Continuum Model  

SciTech Connect (OSTI)

The ruthenium “blue dimer” [(bpy)2RuIIIOH2]2O4+ is best known as the first well-defined molecular catalyst for water oxidation. It has been subject to numerous computational studies primarily employing density functional theory. However, those studies have been limited in the functionals, basis sets, and continuum models employed. The controversy in the calculated electronic structure and the reaction energetics of this catalyst highlights the necessity of benchmark calculations that explore the role of density functionals, basis sets, and continuum models upon the essential features of blue-dimer reactivity. In this paper, we report Kohn-Sham complete basis set (KS-CBS) limit extrapolations of the electronic structure of “blue dimer” using GGA (BPW91 and BP86), hybrid-GGA (B3LYP), and meta-GGA (M06-L) density functionals. The dependence of solvation free energy corrections on the different cavity types (UFF, UA0, UAHF, UAKS, Bondi, and Pauling) within polarizable and conductor-like polarizable continuum model has also been investigated. The most common basis sets of double-zeta quality are shown to yield results close to the KS-CBS limit; however, large variations are observed in the reaction energetics as a function of density functional and continuum cavity model employed.

Ozkanlar, Abdullah; Clark, Aurora E.

2012-05-23T23:59:59.000Z

468

Bayesian modelling of an absolute chronology for Egypt's 18th Dynasty by astrophysical and radiocarbon methods  

E-Print Network [OSTI]

1 Bayesian modelling of an absolute chronology for Egypt's 18th Dynasty by astrophysical Egyptology, the establishment of an absolute chronology for Ancient Egypt has been an ambition which has contained lists of the kings who reigned in Egypt. The Palermo Stone, the Abydos reliefs and the Turin Canon

Paris-Sud XI, Université de

469

Elevated Temperature Primary Load Design Method Using Pseudo Elastic-Perfectly Plastic Model  

SciTech Connect (OSTI)

A new primary load design method for elevated temperature service has been developed. Codification of the procedure in an ASME Boiler and Pressure Vessel Code, Section III Code Case is being pursued. The proposed primary load design method is intended to provide the same margins on creep rupture, yielding and creep deformation for a component or structure that are implicit in the allowable stress data. It provides a methodology that does not require stress classification and is also applicable to a full range of temperature above and below the creep regime. Use of elastic-perfectly plastic analysis based on allowable stress with corrections for constraint, steady state stress and creep ductility is described. This approach is intended to ensure that traditional primary stresses are the basis for design, taking into account ductility limits to stress re-distribution and multiaxial rupture criteria.

Carter, Peter [Stress Engineering Services Inc.] [Stress Engineering Services Inc.; Sham, Sam [ORNL] [ORNL; Jetter, Robert I [Consultant] [Consultant

2012-01-01T23:59:59.000Z

470

Seismic and Rockphysics Diagnostics of Multiscale Reservoir Textures  

SciTech Connect (OSTI)

This final technical report summarizes the results of the work done in this project. The main objective was to quantify rock microstructures and their effects in terms of elastic impedances in order to quantify the seismic signatures of microstructures. Acoustic microscopy and ultrasonic measurements were used to quantify microstructures and their effects on elastic impedances in sands and shales. The project led to the development of technologies for quantitatively interpreting rock microstructure images, understanding the effects of sorting, compaction and stratification in sediments, and linking elastic data with geologic models to estimate reservoir properties. For the public, ultimately, better technologies for reservoir characterization translates to better reservoir development, reduced risks, and hence reduced energy costs.

Gary Mavko

2005-07-01T23:59:59.000Z

471

THIN LAYER MODELS FOR ELECTROMAGNETISM MARC DURUFLE, VICTOR PERON, AND CLAIR POIGNARD  

E-Print Network [OSTI]

THIN LAYER MODELS FOR ELECTROMAGNETISM MARC DURUFL´E, VICTOR P´ERON, AND CLAIR POIGNARD ABSTRACT of electromagnetic waves in domains with thin layer. These models appear as first order approximations of the electromagnetic field. They are obtained thanks to a multiscale expansion of the exact solution with respect

Paris-Sud XI, Université de

472

JOM: Journal of the Minerals, Metals, and Materials Society, 2012, Vol. 62, Issue 10, pp. 1148-1157 Thermal expansion of carbon nanofiber reinforced multiscale polymer composites  

E-Print Network [OSTI]

-1157 Thermal expansion of carbon nanofiber reinforced multiscale polymer composites Ronald Poveda, Sriniket. Keywords: Polymer matrix composite; nanocomposite; carbon nanofibers; thermal properties; coefficient materials. Therefore, understanding the trends observed in the CTE of composites with respect

Gupta, Nikhil

473

Systems, methods and computer-readable media to model kinetic performance of rechargeable electrochemical devices  

DOE Patents [OSTI]

A system includes an electrochemical cell, monitoring hardware, and a computing system. The monitoring hardware samples performance characteristics of the electrochemical cell. The computing system determines cell information from the performance characteristics. The computing system also analyzes the cell information of the electrochemical cell with a Butler-Volmer (BV) expression modified to determine exchange current density of the electrochemical cell by including kinetic performance information related to pulse-time dependence, electrode surface availability, or a combination thereof. A set of sigmoid-based expressions may be included with the modified-BV expression to determine kinetic performance as a function of pulse time. The determined exchange current density may be used with the modified-BV expression, with or without the sigmoid expressions, to analyze other characteristics of the electrochemical cell. Model parameters can be defined in terms of cell aging, making the overall kinetics model amenable to predictive estimates of cell kinetic performance along the aging timeline.

Gering, Kevin L.

2013-01-01T23:59:59.000Z

474

REPRESENTING AEROSOL DYNAMICS AND PROPERTIES IN CHEMICAL TRANSPORT MODELS BY THE METHOD OF MOMENTS.  

SciTech Connect (OSTI)

Atmospheric aerosols, suspensions of solid or liquid particles, are an important multi-phase system. Aerosols scatter and absorb shortwave (solar) radiation, affecting climate (Charlson et al., 1992; Schwartz, 1996) and visibility; nucleate cloud droplet formation, modifying the reflectivity of clouds (Twomey et al., 1984; Schwartz and Slingo, 1996) as well as contributing to composition of cloudwater and to wet deposition (Seinfeld and Pandis, 1998); and affect human health through inhalation (NRC, 1998). Existing and prospective air quality regulations impose standards on concentrations of atmospheric aerosols to protect human health and welfare (EPA, 1998). Chemical transport and transformation models representing the loading and geographical distribution of aerosols and precursor gases are needed to permit development of effective and efficient strategies for meeting air quality standards, and for examining aerosol effects on climate retrospectively and prospectively for different emissions scenarios. Important aerosol properties and processes depend on their size distribution: light scattering, cloud nucleating properties, dry deposition, and penetration into airways of lungs. The evolution of the mass loading itself depends on particle size because of the size dependence of growth and removal processes. For these reasons it is increasingly recognized that chemical transport and transformation models must represent not just the mass loading of atmospheric particulate matter but also the aerosol microphysical properties and the evolution of these properties if aerosols are to be accurately represented in these models. If the size distribution of the aerosol is known, a given property can be evaluated as the integral of the appropriate kernel function over the size distribution. This has motivated the approach of determining aerosol size distribution, and of explicitly representing this distribution and its evolution in chemical transport models.

SCHWARTZ,S.E.; MCGRAW,R.; BENKOVITZ,C.M.; WRIGHT,D.L.

2001-04-01T23:59:59.000Z

475

Economics definitions, methods, models, and analysis procedures for Homeland Security applications.  

SciTech Connect (OSTI)

This report gives an overview of the types of economic methodologies and models used by Sandia economists in their consequence analysis work for the National Infrastructure Simulation&Analysis Center and other DHS programs. It describes the three primary resolutions at which analysis is conducted (microeconomic, mesoeconomic, and macroeconomic), the tools used at these three levels (from data analysis to internally developed and publicly available tools), and how they are used individually and in concert with each other and other infrastructure tools.

Ehlen, Mark Andrew; Loose, Verne William; Vargas, Vanessa N.; Smith, Braeton J.; Warren, Drake E.; Downes, Paula Sue; Eidson, Eric D.; Mackey, Greg Edward

2010-01-01T23:59:59.000Z

476

A Multiscale Study of Polycyclic Aromatic Hydrocarbon Properties in Galaxies  

E-Print Network [OSTI]

In the present contribution, I summarize a systematic study of ISO and Spitzer mid-IR spectra of Galactic regions and star forming galaxies. This study quantifies the relative variations of the main aromatic features inside spatially resolved objects as well as among the integrated spectra of 50 objects. Our analysis implies that the properties of the PAHs are remarkably universal throughout our sample and at different spatial scales. In addition, the relative variations of the band ratios, as large as one order of magnitude, are mainly controled by the fraction of ionized PAHs. In particular, I show that we can rule out both the modification of the PAH size distribution and the mid-IR extinction, as an explanation of these variations. High values of the I(6.2)/I(11.3) ratio are found to be associated with the far-UV illuminated surface of PDRs, at the scale of an interstellar cloud, and associated with star formation activity, at the scale of a galaxy. Using a few well-studied Galactic regions, we provide an empirical relation between the I(6.2)/I(11.3) ratio and the ionization/recombination ratio G0/ne. Finally, I show that these trends are consistent with the detailed modeling of the PAH emission within photodissociation regions, taking into account the radiative transfer, the stochastic heating and the charge exchange between gas and dust.

F. Galliano

2008-02-16T23:59:59.000Z

477

Geoelectrical Measurement of Multi-Scale Mass Transfer Parameters  

SciTech Connect (OSTI)

Mass transfer affects contaminant transport and is thought to control the efficiency of aquifer remediation at a number of sites within the Department of Energy (DOE) complex. An improved understanding of mass transfer is critical to meeting the enormous scientific and engineering challenges currently facing DOE. Informed design of site remedies and long-term stewardship of radionuclide-contaminated sites will require new cost-effective laboratory and field techniques to measure the parameters controlling mass transfer spatially and across a range of scales. In this project, we sought to capitalize on the geophysical signatures of mass transfer. Previous numerical modeling and pilot-scale field experiments suggested that mass transfer produces a geoelectrical signature—a hysteretic relation between sampled (mobile-domain) fluid conductivity and bulk (mobile + immobile) conductivity—over a range of scales relevant to aquifer remediation. In this work, we investigated the geoelectrical signature of mass transfer during tracer transport in a series of controlled experiments to determine the operation of controlling parameters, and also investigated the use of complex-resistivity (CR) as a means of quantifying mass transfer parameters in situ without tracer experiments. In an add-on component to our grant, we additionally considered nuclear magnetic resonance (NMR) to help parse mobile from immobile porosities. Including the NMR component, our revised study objectives were to: 1. Develop and demonstrate geophysical approaches to measure mass-transfer parameters spatially and over a range of scales, including the combination of electrical resistivity monitoring, tracer tests, complex resistivity, nuclear magnetic resonance, and materials characterization; and 2. Provide mass-transfer estimates for improved understanding of contaminant fate and transport at DOE sites, such as uranium transport at the Hanford 300 Area. To achieve our objectives, we implemented a 3-part research plan involving (1) development of computer codes and techniques to estimate mass-transfer parameters from time-lapse electrical data; (2) bench-scale experiments on synthetic materials and materials from cores from the Hanford 300 Area; and (3) field demonstration experiments at the DOE’s Hanford 300 Area. In a synergistic add-on to our workplan, we analyzed data from field experiments performed at the DOE Naturita Site under a separate DOE SBR grant, on which PI Day-Lewis served as co-PI. Techniques developed for application to Hanford datasets also were applied to data from Naturita.

Day-Lewis, Frederick David [U.S. Geological Survey; Singha, Kamini [Colorado School of Mines; Johnson, Timothy C. [Pacific Northwest National Laboratory; Haggerty, Roy [Oregon State; Binley, Andrew [Lancaster University; Lane, John W. [US Geological Survey

2014-11-25T23:59:59.000Z

478

COBRA-SFS (Spent Fuel Storage): A thermal-hydraulic analysis computer code: Volume 1, Mathematical models and solution method  

SciTech Connect (OSTI)

COBRA-SFS (Spent Fuel Storage) is a general thermal-hydraulic analysis computer code used to predict temperatures and velocities in a wide variety of systems. The code was refined and specialized for spent fuel storage system analyses for the US Department of Energy's Commercial Spent Fuel Management Program. The finite-volume equations governing mass, momentum, and energy conservation are written for an incompressible, single-phase fluid. The flow equations model a wide range of conditions including natural circulation. The energy equations include the effects of solid and fluid conduction, natural convection, and thermal radiation. The COBRA-SFS code is structured to perform both steady-state and transient calculations: however, the transient capability has not yet been validated. This volume describes the finite-volume equations and the method used to solve these equations. It is directed toward the user who is interested in gaining a more complete understanding of these methods.

Rector, D.R.; Wheeler, C.L.; Lombardo, N.J.

1986-11-01T23:59:59.000Z

479

Methods for modeling impact-induced reactivity changes in small reactors.  

SciTech Connect (OSTI)

This paper describes techniques for determining impact deformation and the subsequent reactivity change for a space reactor impacting the ground following a potential launch accident or for large fuel bundles in a shipping container following an accident. This technique could be used to determine the margin of subcriticality for such potential accidents. Specifically, the approach couples a finite element continuum mechanics model (Pronto3D or Presto) with a neutronics code (MCNP). DAGMC, developed at the University of Wisconsin-Madison, is used to enable MCNP geometric queries to be performed using Pronto3D output. This paper summarizes what has been done historically for reactor launch analysis, describes the impact criticality analysis methodology, and presents preliminary results using representative reactor designs.

Tallman, Tyler N.; Radel, Tracy E.; Smith, Jeffrey A.; Villa, Daniel L.; Smith, Brandon M. (U. of Wisconsin, Madison, WI); Radel, Ross F.; Lipinski, Ronald J.; Wilson, Paul Philip Hood (U. of Wisconsin, Madison, WI)

2010-10-01T23:59:59.000Z

480

A Study of Scientometric Methods to Identify Emerging Technologies via Modeling of Milestones  

SciTech Connect (OSTI)

This work examines a scientometric model that tracks the emergence of an identified technology from initial discovery (via original scientific and conference literature), through critical discoveries (via original scientific, conference literature and patents), transitioning through Technology Readiness Levels (TRLs) and ultimately on to commercial application. During the period of innovation and technology transfer, the impact of scholarly works, patents and on-line web news sources are identified. As trends develop, currency of citations, collaboration indicators, and on-line news patterns are identified. The combinations of four distinct and separate searchable on-line networked sources (i.e., scholarly publications and citation, patents, news archives, and online mapping networks) are assembled to become one collective network (a dataset for analysis of relations). This established network becomes the basis from which to quickly analyze the temporal flow of activity (searchable events) for the example subject domain we investigated.

Abercrombie, Robert K [ORNL; Udoeyop, Akaninyene W [ORNL; Schlicher, Bob G [ORNL

2012-01-01T23:59:59.000Z

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


481

Adapting to a Changing Environment: Non-obvious Thresholds in Multi-Scale Systems  

E-Print Network [OSTI]

Many natural and technological systems fail to adapt to changing external conditions and move to a different state if the conditions vary too fast. Such "non-adiabatic" processes are ubiquitous, but little understood. We identify these processes with a new nonlinear phenomenon---an intricate threshold where a forced system fails to adiabatically follow a changing stable state. In systems with multiple time-scales such thresholds are generic, but non-obvious, meaning they cannot be captured by traditional stability theory. Rather, the phenomenon can be analysed using concepts from modern singular perturbation theory: folded singularities and canard trajectories, including composite canards. Thus, non-obvious thresholds should explain the failure to adapt to a changing environment in a wide range of multi-scale systems including: tipping points in the climate system, regime shifts in ecosystems, excitability in nerve cells, adaptation failure in regulatory genes, and adiabatic switching in technology.

Clare Perryman; Sebastian Wieczorek

2014-07-09T23:59:59.000Z

482