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1

DRIFT-SCALE COUPLED PROCESSES (DST AND TH SEEPAGE) MODELS  

SciTech Connect (OSTI)

The purpose of this report is to document drift-scale modeling work performed to evaluate the thermal-hydrological (TH) behavior in Yucca Mountain fractured rock close to waste emplacement drifts. The heat generated by the decay of radioactive waste results in rock temperatures elevated from ambient for thousands of years after emplacement. Depending on the thermal load, these temperatures are high enough to cause boiling conditions in the rock, giving rise to water redistribution and altered flow paths. The predictive simulations described in this report are intended to investigate fluid flow in the vicinity of an emplacement drift for a range of thermal loads. Understanding the TH coupled processes is important for the performance of the repository because the thermally driven water saturation changes affect the potential seepage of water into waste emplacement drifts. Seepage of water is important because if enough water gets into the emplacement drifts and comes into contact with any exposed radionuclides, it may then be possible for the radionuclides to be transported out of the drifts and to the groundwater below the drifts. For above-boiling rock temperatures, vaporization of percolating water in the fractured rock overlying the repository can provide an important barrier capability that greatly reduces (and possibly eliminates) the potential of water seeping into the emplacement drifts. In addition to this thermal process, water is inhibited from entering the drift opening by capillary forces, which occur under both ambient and thermal conditions (capillary barrier). The combined barrier capability of vaporization processes and capillary forces in the near-field rock during the thermal period of the repository is analyzed and discussed in this report.

J.T. Birkholzer; S. Mukhopadhyay

2005-01-13T23:59:59.000Z

2

Testing emotion dysregulation as a moderator in an interpersonal process model of intimacy in couples  

E-Print Network [OSTI]

-disclosure by one partner, coupled with empathic responding by the other partner, results in greater subjective emotional intimacy. Previous studies have examined this interpersonal process model in a sample of community couples in committed romantic relationships...

Herrington, Rachael

2009-05-15T23:59:59.000Z

3

Report on Modeling Coupled Processes in the Near Field of a Clay Repository  

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

on Modeling Coupled Processes in the Near Field of a Clay on Modeling Coupled Processes in the Near Field of a Clay Repository Report on Modeling Coupled Processes in the Near Field of a Clay Repository Clay/shale has been considered as potential host rock for geological disposal of high-level radioactive waste throughout the world. Coupled thermal, hydrological, mechanical, and chemical (THMC) processes have a significant impact on the long-term safety of a clay repository. This report documents results from three R&D activities: (1) implementation and validation of constitutive relationships, (2) development of a discrete fracture network (DFN) model for investigating coupled processes in the excavation damaged zone, and (3) development of a THM model for the Full-Scale Emplacement Experiment tests at Mont Terri, Switzerland, for the

4

Hybrid models for the simulation of microstructural evolution influenced by coupled, multiple physical processes.  

SciTech Connect (OSTI)

Most materials microstructural evolution processes progress with multiple processes occurring simultaneously. In this work, we have concentrated on the processes that are active in nuclear materials, in particular, nuclear fuels. These processes are coarsening, nucleation, differential diffusion, phase transformation, radiation-induced defect formation and swelling, often with temperature gradients present. All these couple and contribute to evolution that is unique to nuclear fuels and materials. Hybrid model that combines elements from the Potts Monte Carlo, phase-field models and others have been developed to address these multiple physical processes. These models are described and applied to several processes in this report. An important feature of the models developed are that they are coded as applications within SPPARKS, a Sandiadeveloped framework for simulation at the mesoscale of microstructural evolution processes by kinetic Monte Carlo methods. This makes these codes readily accessible and adaptable for future applications.

Tikare, Veena; Hernandez-Rivera, Efrain; Madison, Jonathan D.; Holm, Elizabeth Ann [Carnegie Mellon University, Pittsburgh, PA; Patterson, Burton R. [University of Florida, Gainesville, FL; Homer, Eric R. [Brigham Young University, Provo, UT

2013-09-01T23:59:59.000Z

5

Modeling Coupled THMC Processes and Brine Migration in Salt at High Temperatures  

SciTech Connect (OSTI)

In this report, we present FY2014 progress by Lawrence Berkeley National Laboratory (LBNL) related to modeling of coupled thermal-hydrological-mechanical-chemical (THMC) processes in salt and their effect on brine migration at high temperatures. LBNL’s work on the modeling of coupled THMC processes in salt was initiated in FY2012, focusing on exploring and demonstrating the capabilities of an existing LBNL modeling tool (TOUGH-FLAC) for simulating temperature-driven coupled flow and geomechanical processes in salt. This work includes development related to, and implementation of, essential capabilities, as well as testing the model against relevant information and published experimental data related to the fate and transport of water. we provide more details on the FY2014 work, first presenting updated tools and improvements made to the TOUGH-FLAC simulator, and the use of this updated tool in a new model simulation of long-term THM behavior within a generic repository in a salt formation. This is followed by the description of current benchmarking and validations efforts, including the TSDE experiment. We then present the current status in the development of constitutive relationships and the dual-continuum model for brine migration. We conclude with an outlook for FY2015, which will be much focused on model validation against field experiments and on the use of the model for the design studies related to a proposed heater experiment.

Rutqvist, Jonny; Blanco Martin, Laura; Mukhopadhyay, Sumit; Houseworth, Jim; Birkholzer, Jens

2014-08-14T23:59:59.000Z

6

MASSIVELY PARALLEL FULLY COUPLED IMPLICIT MODELING OF COUPLED THERMAL-HYDROLOGICAL-MECHANICAL PROCESSES FOR ENHANCED GEOTHERMAL SYSTEM RESERVOIRS  

SciTech Connect (OSTI)

Development of enhanced geothermal systems (EGS) will require creation of a reservoir of sufficient volume to enable commercial-scale heat transfer from the reservoir rocks to the working fluid. A key assumption associated with reservoir creation/stimulation is that sufficient rock volumes can be hydraulically fractured via both tensile and shear failure, and more importantly by reactivation of naturally existing fractures (by shearing) to create the reservoir. The advancement of EGS greatly depends on our understanding of the dynamics of the intimately coupled rock-fracture-fluid system and our ability to reliably predict how reservoirs behave under stimulation and production. In order to increase our understanding of how reservoirs behave under these conditions, we have developed a physics-based rock deformation and fracture propagation simulator by coupling a discrete element model (DEM) for fracturing with a continuum multiphase flow and heat transport model. In DEM simulations, solid rock is represented by a network of discrete elements (often referred as particles) connected by various types of mechanical bonds such as springs, elastic beams or bonds that have more complex properties (such as stress-dependent elastic constants). Fracturing is represented explicitly as broken bonds (microcracks), which form and coalesce into macroscopic fractures when external load is applied. DEM models have been applied to a very wide range of fracturing processes from the molecular scale (where thermal fluctuations play an important role) to scales on the order of 1 km or greater. In this approach, the continuum flow and heat transport equations are solved on an underlying fixed finite element grid with evolving porosity and permeability for each grid cell that depends on the local structure of the discrete element network (such as DEM particle density). The fluid pressure gradient exerts forces on individual elements of the DEM network, which therefore deforms and fractures. Such deformation/fracturing in turn changes the permeability, which again changes the evolution of fluid pressure, coupling the two phenomena. The intimate coupling between fracturing and fluid flow makes the meso-scale DEM simulations necessary, as these methods have substantial advantages over conventional continuum mechanical models of elastic rock deformation. The challenges that must be overcome to simulate EGS reservoir stimulation, preliminary results, progress to date and near future research directions and opportunities will be discussed.

Robert Podgorney; Hai Huang; Derek Gaston

2010-02-01T23:59:59.000Z

7

Modeling the coupled mechanics, transport, and growth processes in collagen tissues.  

SciTech Connect (OSTI)

The purpose of this project is to develop tools to model and simulate the processes of self-assembly and growth in biological systems from the molecular to the continuum length scales. The model biological system chosen for the study is the tendon fiber which is composed mainly of Type I collagen fibrils. The macroscopic processes of self-assembly and growth at the fiber scale arise from microscopic processes at the fibrillar and molecular length scales. At these nano-scopic length scales, we employed molecular modeling and simulation method to characterize the mechanical behavior and stability of the collagen triple helix and the collagen fibril. To obtain the physical parameters governing mass transport in the tendon fiber we performed direct numerical simulations of fluid flow and solute transport through an idealized fibrillar microstructure. At the continuum scale, we developed a mixture theory approach for modeling the coupled processes of mechanical deformation, transport, and species inter-conversion involved in growth. In the mixture theory approach, the microstructure of the tissue is represented by the species concentration and transport and material parameters, obtained from fibril and molecular scale calculations, while the mechanical deformation, transport, and growth processes are governed by balance laws and constitutive relations developed within a thermodynamically consistent framework.

Holdych, David J.; Nguyen, Thao D.; Klein, Patrick A.; in't Veld, Pieter J.; Stevens, Mark Jackson

2006-11-01T23:59:59.000Z

8

Theory and computational modeling: Medium reorganization and donor/acceptor coupling in electron transfer processes  

SciTech Connect (OSTI)

The continuing goal is to convert the rapidly accumulating mechanistic information about electron transfer (et) kinetics (often representable in terms of simple rate constants) into precise tools for fine-tuned control of the kinetics and for design of molecular-based systems which meet specified et characteristics. The present treatment will be limited to the kinetic framework defined by the assumption of transition state theory (TST). The primary objective of this paper is to report recent advances in the theoretical formulation, calculation, and analysis of energetics and electronic coupling pertinent to et in complex molecular aggregates. The control of et kinetics (i.e., enhancing desired processes, while inhibiting others) involves, of course, both system energetics (especially reorganization energies (E{sub r}) and free energy changes ({Delta}G{sup 0})) and electronic coupling of local D and A sites, which for thermal processes is most directly relevant only after the system has reached the appropriate point (or region) along the reaction coordinate (i.e., the transition state). The authors first discuss TST rate constant models, emphasizing genetic features, but also noting some special features arising when metal electrodes are involved. They then turn to a consideration of detailed aspects of medium reorganization and donor/acceptor coupling. With these theoretical tools in hand, they examine the results of recent applications to complex molecular systems using the techniques of computational quantum chemistry and electrostatics, together with detailed analysis of the numerical results and comparison with recent electrochemical kinetic data.

Newton, M.D.; Feldberg, S.W.; Smalley, J.F.

1998-03-01T23:59:59.000Z

9

Vehicle Technologies Office Merit Review 2014: Coupled Hierarchical Models for Thermal, Mechanical, Electrical and Electrochemical Processes  

Broader source: Energy.gov [DOE]

Presentation given by [company name] at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about coupled hierarchical models...

10

3D Modeling of Coupled Rock Deformation and Thermo-Poro-Mechanical Processes in Fractures  

E-Print Network [OSTI]

Problems involving coupled thermo-poro-chemo-mechanical processes are of great importance in geothermal and petroleum reservoir systems. In particular, economic power production from enhanced geothermal systems, effective water-flooding of petroleum...

Rawal, Chakra

2012-07-16T23:59:59.000Z

11

Using the Model Coupling Toolkit to couple earth system models  

Science Journals Connector (OSTI)

Continued advances in computational resources are providing the opportunity to operate more sophisticated numerical models. Additionally, there is an increasing demand for multidisciplinary studies that include interactions between different physical processes. Therefore there is a strong desire to develop coupled modeling systems that utilize existing models and allow efficient data exchange and model control. The basic system would entail model “1” running on “M” processors and model “2” running on “N” processors, with efficient exchange of model fields at predetermined synchronization intervals. Here we demonstrate two coupled systems: the coupling of the ocean circulation model Regional Ocean Modeling System (ROMS) to the surface wave model Simulating \\{WAves\\} Nearshore (SWAN), and the coupling of ROMS to the atmospheric model Coupled Ocean Atmosphere Prediction System (COAMPS). Both coupled systems use the Model Coupling Toolkit (MCT) as a mechanism for operation control and inter-model distributed memory transfer of model variables. In this paper we describe requirements and other options for model coupling, explain the MCT library, ROMS, SWAN and COAMPS models, methods for grid decomposition and sparse matrix interpolation, and provide an example from each coupled system. Methods presented in this paper are clearly applicable for coupling of other types of models.

John C. Warner; Natalie Perlin; Eric D. Skyllingstad

2008-01-01T23:59:59.000Z

12

Coupled Thermal-Hydrological-Mechanical Processes in Salt, Hot...  

Office of Environmental Management (EM)

Coupled Thermal-Hydrological-Mechanical Processes in Salt, Hot Granular Salt Consolidation, Constitutive Model and Micromechanics Coupled Thermal-Hydrological-Mechanical Processes...

13

The Model Coupling Toolkit  

Science Journals Connector (OSTI)

The advent of coupled earth system models has raised an important question in parallel computing: What is the most effective method for coupling many parallel models to form one high-performance coupled modeling system? We present our solution to this ...

Jay Walter Larson; Robert L. Jacob; Ian T. Foster; Jing Guo

2001-05-01T23:59:59.000Z

14

Coupling glacial lake impact, dam breach, and flood processes: A modeling perspective  

Science Journals Connector (OSTI)

Abstract Glacial lake outburst floods (GLOFs) are highly mobile mixtures of water and sediment that occur suddenly and are capable of traveling tens to hundreds of kilometers with peak discharges and volumes several orders of magnitude larger than those of normal floods. They travel along existing river channels, in some instances into populated downstream regions, and thus pose a risk to people and infrastructure. Many recent events involve process chains, such as mass movements impacting glacial lakes and triggering dam breaches with subsequent outburst floods. A concern is that effects of climate change and associated increased instability of high mountain slopes may exacerbate such process chains and associated extreme flows. Modeling tools can be used to assess the hazard of potential future GLOFs, and process modeling can provide insights into complex processes that are difficult to observe in nature. A number of numerical models have been developed and applied to simulate different types of extreme flows, but such modeling faces challenges stemming from a lack of process understanding and difficulties in measuring extreme flows for calibration purposes. Here we review the state of knowledge of key aspects of modeling GLOFs, with a focus on process cascades. Analysis and simulation of the onset, propagation, and potential impact of \\{GLOFs\\} are based on illustrative case studies. Numerical models are presently available for simulating impact waves in lakes, dam failures, and flow propagation but have been used only to a limited extent for integrated simulations of process cascades. We present a spectrum of case studies from Patagonia, the European Alps, central Asia, and the Himalayas in which we simulate single processes and process chains of past and potential future events. We conclude that process understanding and process chain modeling need to be strengthened and that research efforts should focus on a more integrative treatment of processes in numerical models.

Raphael Worni; Christian Huggel; John J. Clague; Yvonne Schaub; Markus Stoffel

2014-01-01T23:59:59.000Z

15

Modeling shear failure and permeability enhancement due to coupled Thermal-Hydrological-Mechanical processes in Enhanced Geothermal Reservoirs  

SciTech Connect (OSTI)

The connectivity and accessible surface area of flowing fractures, whether natural or man-made, is possibly the single most important factor, after temperature, which determines the feasibility of an Enhanced Geothermal System (EGS). Rock deformation and in-situ stress changes induced by injected fluids can lead to shear failure on preexisting fractures which can generate microseismic events, and also enhance the permeability and accessible surface area of the geothermal formation. Hence, the ability to accurately model the coupled thermal-hydrologic-mechanical (THM) processes in fractured geological formations is critical in effective EGS reservoir development and management strategies. The locations of the microseismic events can serve as indicators of the zones of enhanced permeability, thus providing vital information for verification of the coupled THM models. We will describe a general purpose computational code, FEHM, developed for this purpose, that models coupled THM processes during multiphase fluid flow and transport in fractured porous media. The code incorporates several models of fracture aperture and stress behavior combined with permeability relationships. We provide field scale examples of applications to geothermal systems to demonstrate the utility of the method.

Kelkar, Sharad [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

16

The model coupling toolkit.  

SciTech Connect (OSTI)

The advent of coupled earth system models has raised an important question in parallel computing: What is the most effective method for coupling many parallel models to form a high-performance coupled modeling system? We present our solution to this problem--The Model Coupling Toolkit (MCT). We explain how our effort to construct the Next-Generation Coupler for NCAR Community Climate System Model motivated us to create this toolkit. We describe in detail the conceptual design of the MCT and explain its usage in constructing parallel coupled models. We present preliminary performance results for the toolkit's parallel data transfer facilities. Finally, we outline an agenda for future development of the MCT.

Larson, J. W.; Jacob, R. L.; Foster, I.; Guo, J.

2001-04-13T23:59:59.000Z

17

Testing an interpersonal process model of intimacy using intimate discussions of committed romantic couples  

E-Print Network [OSTI]

- and partner-reports of self-disclosure, empathic responding, and emotional intimacy. In this study, data were collected on 108 committed romantic couples from the community. Couples completed a packet of questionnaires individually and then engaged...

Castellani, Angela Marie

2006-08-16T23:59:59.000Z

18

Towards the Prediction of Decadal to Centennial Climate Processes in the Coupled Earth System Model  

SciTech Connect (OSTI)

In this proposal, we have made major advances in the understanding of decadal and long term climate variability. (a) We performed a systematic study of multidecadal climate variability in FOAM-LPJ and CCSM-T31, and are starting exploring decadal variability in the IPCC AR4 models. (b) We develop several novel methods for the assessment of climate feedbacks in the observation. (c) We also developed a new initialization scheme DAI (Dynamical Analogue Initialization) for ensemble decadal prediction. (d) We also studied climate-vegetation feedback in the observation and models. (e) Finally, we started a pilot program using Ensemble Kalman Filter in CGCM for decadal climate prediction.

Zhengyu Liu, J. E. Kutzbach, R. Jacob, C. Prentice

2011-12-05T23:59:59.000Z

19

Randomly coupled Ising models  

Science Journals Connector (OSTI)

We consider the phase diagram of two randomly coupled Ising models to mimic the successive phase transitions in plastic crystals. Detailed mean-field calculations are performed. Depending on the strength of the couplings, the phase diagrams display three ordered phases and some multicritical points. A tetracritical point is found to turn bicritical as the strength of the couplings increases. The nature of this multicritical point is then analyzed by means of a momentum-space renormalization-group calculation. Using the replica trick, we obtain an effective n-component spin Hamiltonian. The random coupling is found to be relevant and shown to have drastic effects on the multicritical behavior. The lower critical dimension is estimated to be dl=2. In the n=0 limit, to first order in the parameter ?=4-d, a system of seven recursion relations is obtained. Although there is a stable fixed point, it cannot be reached from physically acceptable initial conditions. We give arguments to support a runaway of the flow lines associated with a fluctuation-induced first-order transition.

S. Galam; S. R. Salinas; Y. Shapir

1995-02-01T23:59:59.000Z

20

Effects of vegetation and soil moisture on the simulated land surface processes from the coupled WRF/Noah model  

E-Print Network [OSTI]

simulations. Meso- scale models, which have been used not only for numerical weather prediction but also surface and atmosphere into numerical weather or climate prediction. This study describes coupled WRF [Chen et al., 1997; Pielke et al., 1997]. Numerical weather prediction with high spatial and tempo- ral

Small, Eric

Note: This page contains sample records for the topic "modeling coupled processes" 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

Edinburgh Research Explorer Processivity and Coupling in Messenger RNA Transcription  

E-Print Network [OSTI]

Edinburgh Research Explorer Processivity and Coupling in Messenger RNA Transcription Citation and processing that is not captured in the model. Methodology: In this paper, we explore the impact on the m, 'Processivity and Coupling in Messenger RNA Transcription' PLoS One, vol 5, no. 1, e8845, pp. 1-12., 10

Millar, Andrew J.

22

Synthesis report on thermally driven coupled processes  

SciTech Connect (OSTI)

The main purpose of this report is to document observations and data on thermally coupled processes for conditions that are expected to occur within and around a repository at Yucca Mountain. Some attempt is made to summarize values of properties (e.g., thermal properties, hydrologic properties) that can be measured in the laboratory on intact samples of the rock matrix. Variation of these properties with temperature, or with conditions likely to be encountered at elevated temperature in the host rock, is of particular interest. However, the main emphasis of this report is on direct observation of thermally coupled processes at various scales. Direct phenomenological observations are vitally important in developing and testing conceptual models. If the mathematical implementation of a conceptual model predicts a consequence that is not observed, either (1) the parameters or the boundary conditions used in the calculation are incorrect or (2) the conceptual basis of the model does not fit the experiment; in either case, the model must be revised. For example, the effective continuum model that has been used in thermohydrology studies combines matrix and fracture flow in a way that is equivalent to an assumption that water is imbibed instantaneously from fractures into adjacent, partially saturated matrix. Based on this approximation, the continuum-flow response that is analogous to fracture flow will not occur until the effective continuum is almost completely saturated. This approximation is not entirely consistent with some of the experimental data presented in this report. This report documents laboratory work and field studies undertaken in FY96 and FY97 to investigate thermally coupled processes such as heat pipes and fracture-matrix coupling. In addition, relevant activities from past years, and work undertaken outside the Yucca Mountain project are summarized and discussed. Natural and artificial analogs are also discussed to provide a convenient source of material documenting the conceptual and mathematical basis for modeling coupled phenomena. The actual models and codes, and their specific empirical and theoretical bases, will be documented in a separate report to be delivered in FY99.

Hardin, E.L.

1997-10-15T23:59:59.000Z

23

Using the Model Coupling Toolkit to couple earth system models  

Science Journals Connector (OSTI)

Continued advances in computational resources are providing the opportunity to operate more sophisticated numerical models. Additionally, there is an increasing demand for multidisciplinary studies that include interactions between different physical ... Keywords: COAMPS, Model Coupling Toolkit, Model coupling, ROMS, SWAN, Sparse matrix interpolation

John C. Warner; Natalie Perlin; Eric D. Skyllingstad

2008-10-01T23:59:59.000Z

24

Modelling coupled processes in bentonite: recent results from the UK's contribution to the Äspö EBS Task Force  

Science Journals Connector (OSTI)

...R. (2002) The Buffer and Backfill Handbook Part1: Definitions...bentonite and tunnel backfill knowledge: State-of-the-art...modelling of the bentonite buffer . SKB Technical Report...Stockholm. SKB (2010) Buffer backfill and closure process...

D. Holton; S. Baxter; A. R. Hoch

25

Coupled Thermal-Hydrological-Mechanical Processes in Salt, Hot Granular  

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

Coupled Thermal-Hydrological-Mechanical Processes in Salt, Hot Coupled Thermal-Hydrological-Mechanical Processes in Salt, Hot Granular Salt Consolidation, Constitutive Model and Micromechanics Coupled Thermal-Hydrological-Mechanical Processes in Salt, Hot Granular Salt Consolidation, Constitutive Model and Micromechanics The report addresses granular salt reconsolidation from three vantage points: laboratory testing, modeling, and petrofabrics. The experimental data 1) provide greater insight and understanding into the role of elevated temperature and pressure regimes on physical properties of reconsolidated crushed salt, 2) can supplement an existing database used to develop a reconsolidation constitutive model and 3) provide data for model evaluation. The constitutive model accounts for the effects of moisture through pressure solution and dislocation creep, with both terms dependent

26

Coupled Thermal-Hydrological-Mechanical Processes in Salt, Hot Granular  

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

Coupled Thermal-Hydrological-Mechanical Processes in Salt, Hot Coupled Thermal-Hydrological-Mechanical Processes in Salt, Hot Granular Salt Consolidation, Constitutive Model and Micromechanics Coupled Thermal-Hydrological-Mechanical Processes in Salt, Hot Granular Salt Consolidation, Constitutive Model and Micromechanics The report addresses granular salt reconsolidation from three vantage points: laboratory testing, modeling, and petrofabrics. The experimental data 1) provide greater insight and understanding into the role of elevated temperature and pressure regimes on physical properties of reconsolidated crushed salt, 2) can supplement an existing database used to develop a reconsolidation constitutive model and 3) provide data for model evaluation. The constitutive model accounts for the effects of moisture through pressure solution and dislocation creep, with both terms dependent

27

MCT: Model Coupling Toolkit | Argonne National Laboratory  

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

MCT: Model Coupling Toolkit MCT: Model Coupling Toolkit MCT: Model Coupling Toolkit MCT is a set of open-source software tools for creating coupled models. MCT is fully parallel and can be used to couple message-passing parallel models to create a parallel coupled model. MCT is available as a small library and a set of Fortran90 modules. MCT provides model interoperability through a simple API. Two models that declare and use MCT datatypes can be coupled with a minimum of effort. MCT provides the following core coupling services: A component model registry Domain decomposition descriptors Communications schedulers for parallel MxN intercomponent data transfer and MxM intracomponent data redistribution A flexible and indexible (i.e., random-access) field data storage datatype A time averaging and accumulation buffer datatype

28

MCT--The Model Coupling Toolkit  

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

Model Coupling Toolkit Model Coupling Toolkit MCT is a set of open-source software tools for creating coupled models. MCT is fully parallel and can be used to couple message-passing parallel models to create a parallel coupled model. MCT is available as a small library and a set of Fortran90 modules. MCT provides model interoperability through a simple API. Two models that declare and use MCT datatypes can be coupled with a minimum of effort. MCT provides the following core coupling services: a component model registry domain decomposition descriptors communications schedulers for parallel MxN intercomponent data transfer and MxM intracomponent data redistribution a flexible and indexible (i.e., random-access) field data storage datatype a time averaging and accumulation buffer datatype

29

OVERVIEW OF THE COUPLED MODEL INTERCOMPARISON PROJECT  

Science Journals Connector (OSTI)

The Coupled Model Intercomparison Project (CMIP) involves study and intercomparison of multi-model simulations of present and future climate. The simulations of the future use idealized forcing in increase is compounded which CO2 1% yr?1 until it ...

Gerald A. Meehl; Curt Covey; Bryant McAvaney; Mojib Latif; Ronald J. Stouffer

2005-01-01T23:59:59.000Z

30

Mountain-Scale Coupled Processes (TH/THC/THM)  

SciTech Connect (OSTI)

The purpose of this Model Report is to document the development of the Mountain-Scale Thermal-Hydrological (TH), Thermal-Hydrological-Chemical (THC), and Thermal-Hydrological-Mechanical (THM) Models and evaluate the effects of coupled TH/THC/THM processes on mountain-scale UZ flow at Yucca Mountain, Nevada. This Model Report was planned in ''Technical Work Plan (TWP) for: Performance Assessment Unsaturated Zone'' (BSC 2002 [160819], Section 1.12.7), and was developed in accordance with AP-SIII.10Q, Models. In this Model Report, any reference to ''repository'' means the nuclear waste repository at Yucca Mountain, and any reference to ''drifts'' means the emplacement drifts at the repository horizon. This Model Report provides the necessary framework to test conceptual hypotheses for analyzing mountain-scale hydrological/chemical/mechanical changes and predict flow behavior in response to heat release by radioactive decay from the nuclear waste repository at the Yucca Mountain site. The mountain-scale coupled TH/THC/THM processes models numerically simulate the impact of nuclear waste heat release on the natural hydrogeological system, including a representation of heat-driven processes occurring in the far field. The TH simulations provide predictions for thermally affected liquid saturation, gas- and liquid-phase fluxes, and water and rock temperature (together called the flow fields). The main focus of the TH Model is to predict the changes in water flux driven by evaporation/condensation processes, and drainage between drifts. The TH Model captures mountain-scale three dimensional (3-D) flow effects, including lateral diversion at the PTn/TSw interface and mountain-scale flow patterns. The Mountain-Scale THC Model evaluates TH effects on water and gas chemistry, mineral dissolution/precipitation, and the resulting impact to UZ hydrological properties, flow and transport. The THM Model addresses changes in permeability due to mechanical and thermal disturbances in stratigraphic units above and below the repository host rock. The Mountain-Scale THM Model focuses on evaluating the changes in 3-D UZ flow fields arising out of thermal stress and rock deformation during and after the thermal periods.

P. Dixon

2004-02-09T23:59:59.000Z

31

Coupled Mesh Lagrangian/ALE Modeling:  

National Nuclear Security Administration (NNSA)

Coupled Mesh Lagrangian/ALE Modeling: Coupled Mesh Lagrangian/ALE Modeling: Opportunities and Challenges A. C. Robinson, * J. E. Bishop*, D. M. Hensinger, * T. E. Voth * M. K. Wong * * Sandia National Laboratories, New Mexico, 87185 We describe two methods for coupled mesh Lagrangian/ALE modeling where one mesh is treated as a Lagrangian mesh while the other is ALE. Lagrangian contact modeling is implemented in the first method to couple the two meshes. In the second method an overlapping grid algorithm that requires mapping of the information from one grid to another has been implemented. We review current experience with these two technologies. Introduction Lagrangian modeling is often preferred whenever the kinematics of the continuum flow permit because of its ability to precisely model discrete features which may be

32

Three-dimensional thermo-elastic–plastic finite element modeling of quenching process of plain-carbon steel in couple with phase transformation  

Science Journals Connector (OSTI)

This study focuses on finite element investigations of quenching process which is commonly applied to improve mechanical properties such as strength, hardness, and wear/fatigue resistances, etc. During the quenching process, various kinds of microstructures evolve depending on the cooling rate and temperature variation within the steel. This microstructural evolution has a significant effect on the final dimension and geometry of the mechanical parts. In order to investigate the effect of temperature variation and phase transformation on the dimensional change and stress distribution, thermo-elastic–plastic constitutive equation coupled with the mechanical strain, thermal strain, phase transformation strain, and transformation induced plasticity is described in detail. Using the constitutive equation introduced, a finite element program was developed and used to predict distributions of the temperature, volume fraction of each phase transformed, and stress and dimensional change of the cylindrical specimen, shaft with key groove, and cam-lobe made of carbon steel. It was found out that numerically obtained values such as temperature history and stress distribution were in good agreement with the data available in the literature for the cylindrical carbon steel specimen. The developed program can be used for better understanding of mechanics involved with the quenching process.

Seong-Hoon Kang; Yong-Taek Im

2007-01-01T23:59:59.000Z

33

Boundary coupled dual-equation numerical simulation on mass transfer in the process of laser cladding  

Science Journals Connector (OSTI)

The coupled numerical simulation on fluid flow, heat transfer, and mass transfer in the process of laser cladding is undertaken on the basis of the continuum model. In the...

Huang, Yanlu; Yang, Yongqiang; Wei, Guoqiang; Shi, Wenqing; Li, Yibin

2008-01-01T23:59:59.000Z

34

Effective reuse of coupling technologies for Earth System Models.  

E-Print Network [OSTI]

??Designing and implementing coupled Earth System Models (ESMs) is a challenge for climate scientists and software engineers alike. Coupled models incorporate two or more independent… (more)

Dunlap, Ralph S.

2013-01-01T23:59:59.000Z

35

Coupled Kinetic, Thermal, and Mechanical Modeling of FIB Micro...  

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

Coupled Kinetic, Thermal, and Mechanical Modeling of FIB Micro-machined Electrodes Coupled Kinetic, Thermal, and Mechanical Modeling of FIB Micro-machined Electrodes 2010 DOE...

36

Piezoelectric and Semiconducting Coupled Power Generating Process of a  

E-Print Network [OSTI]

of the electric generator relies on the unique coupling of piezoelectric and semiconducting dual properties of ZnPiezoelectric and Semiconducting Coupled Power Generating Process of a Single ZnO Belt/Wire. A Technology for Harvesting Electricity from the Environment Jinhui Song, Jun Zhou, and Zhong Lin Wang* School

Wang, Zhong L.

37

Hybrid coupled modeling of the tropical Pacific using neural networks  

E-Print Network [OSTI]

Hybrid coupled modeling of the tropical Pacific using neural networks Shuyong Li, William W. Hsieh To investigate the potential for improving hybrid coupled models (HCM) of the tropical Pacific by the use: dynamical coupled models, statistical models and hybrid coupled models [Barnston et al., 1994]. A hybrid

Hsieh, William

38

Process for fabricating a charge coupled device  

DOE Patents [OSTI]

A monolithic three dimensional charged coupled device (3D-CCD) which utilizes the entire bulk of the semiconductor for charge generation, storage, and transfer. The 3D-CCD provides a vast improvement of current CCD architectures that use only the surface of the semiconductor substrate. The 3D-CCD is capable of developing a strong E-field throughout the depth of the semiconductor by using deep (buried) parallel (bulk) electrodes in the substrate material. Using backside illumination, the 3D-CCD architecture enables a single device to image photon energies from the visible, to the ultra-violet and soft x-ray, and out to higher energy x-rays of 30 keV and beyond. The buried or bulk electrodes are electrically connected to the surface electrodes, and an E-field parallel to the surface is established with the pixel in which the bulk electrodes are located. This E-field attracts charge to the bulk electrodes independent of depth and confines it within the pixel in which it is generated. Charge diffusion is greatly reduced because the E-field is strong due to the proximity of the bulk electrodes.

Conder, Alan D. (Tracy, CA); Young, Bruce K. F. (Livermore, CA)

2002-01-01T23:59:59.000Z

39

Biosphere Process Model Report  

SciTech Connect (OSTI)

To evaluate the postclosure performance of a potential monitored geologic repository at Yucca Mountain, a Total System Performance Assessment (TSPA) will be conducted. Nine Process Model Reports (PMRs), including this document, are being developed to summarize the technical basis for each of the process models supporting the TSPA model. These reports cover the following areas: (1) Integrated Site Model; (2) Unsaturated Zone Flow and Transport; (3) Near Field Environment; (4) Engineered Barrier System Degradation, Flow, and Transport; (5) Waste Package Degradation; (6) Waste Form Degradation; (7) Saturated Zone Flow and Transport; (8) Biosphere; and (9) Disruptive Events. Analysis/Model Reports (AMRs) contain the more detailed technical information used to support TSPA and the PMRs. The AMRs consists of data, analyses, models, software, and supporting documentation that will be used to defend the applicability of each process model for evaluating the postclosure performance of the potential Yucca Mountain repository system. This documentation will ensure the traceability of information from its source through its ultimate use in the TSPA-Site Recommendation (SR) and in the National Environmental Policy Act (NEPA) analysis processes. The objective of the Biosphere PMR is to summarize (1) the development of the biosphere model, and (2) the Biosphere Dose Conversion Factors (BDCFs) developed for use in TSPA. The Biosphere PMR does not present or summarize estimates of potential radiation doses to human receptors. Dose calculations are performed as part of TSPA and will be presented in the TSPA documentation. The biosphere model is a component of the process to evaluate postclosure repository performance and regulatory compliance for a potential monitored geologic repository at Yucca Mountain, Nevada. The biosphere model describes those exposure pathways in the biosphere by which radionuclides released from a potential repository could reach a human receptor. Collectively, the potential human receptor and exposure pathways form the biosphere model. More detailed technical information and data about potential human receptor groups and the characteristics of exposure pathways have been developed in a series of AMRs and Calculation Reports.

J. Schmitt

2000-05-25T23:59:59.000Z

40

Population and Climate Change:Population and Climate Change: Coupling Population Models withCoupling Population Models with  

E-Print Network [OSTI]

Coupling Population Models with Earth System ModelsEarth System Models Eugenia Kalnay, Safa Motesharrei, Jorge Rivas Change: Fully Coupling Population and Earth System Models" My research at the U. of Maryland #12

Kalnay, Eugenia

Note: This page contains sample records for the topic "modeling coupled processes" 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

COMPUTER PROCESSING AND MODELING -  

E-Print Network [OSTI]

COMPUTER PROCESSING AND MODELING - Full Paper Magnetic Resonance in Medicine 67:572­579 (2012, Washington University School of Medicine, St. Louis, Missouri, USA Grant sponsor: Mr. and Mrs. Spencer T. Olin Fellowship for Women in Graduate Study; Grant sponsor: NSF; Grant number: CCF-0963742; Grant

Nehorai, Arye

42

Correlation Resonance Generated by Coupled Enzymatic Processing William H. Mather,  

E-Print Network [OSTI]

. Cookson,§ Jeff Hasty,§ Lev S. Tsimring, and Ruth J. Williams{ * Biocircuits Institute, DepartmentCorrelation Resonance Generated by Coupled Enzymatic Processing William H. Mather, Natalie A, R. J. Williams, L. S. Tsimring, and J. Hasty, unpublished). In this study, it was shown that a rate

Hasty, Jeff

43

Correlation resonance generated by coupled enzymatic processing: Supplementary information  

E-Print Network [OSTI]

H. Mather1,2 , Natalie A. Cookson1,3 , Jeff Hasty3,2,1 , Lev S. Tsimring1 and Ruth J. Williams4Correlation resonance generated by coupled enzymatic processing: Supplementary information William Jolla CA 92093-0112 USA. Email: williams@stochastic.ucsd.edu. Throughout this supplement, N and Q

44

Hybrid coupled models of the tropical Pacific: I interannual variability  

E-Print Network [OSTI]

Y. Tang Hybrid coupled models of the tropical Pacific: I interannual variability Received: 20 Two hybrid coupled models (HCMs), an intermediate complexity dynamical ocean model cou- pled to either), hybrid models (e.g., Barnett et al. 1993; Balmaseda et al. 1994,1995), and fully coupled general

Tang, Youmin

45

Modeling of coupled heat transfer and reactive transport processes in porous media: Application to seepage studies at Yucca Mountain, Nevad a  

E-Print Network [OSTI]

Fractured Rock of Yucca Mountain, Nevada: Heterogeneity andfractured rocks of Yucca Mountain have been extensivelyHydrothermal Flow at Yucca Mountain, Part I: Modeling and

Mukhopadhyay, S.; Sonnenthal, E.L.; Spycher, N.

2008-01-01T23:59:59.000Z

46

A tightly coupled GIS and distributed hydrologic modeling framework  

Science Journals Connector (OSTI)

Abstract Distributed, physics-based hydrologic models require spatially explicit specification of parameters related to climate, geology, land-cover, soil, and topography. Extracting these parameters from national geodatabases requires intensive data processing. Furthermore, mapping these parameters to model mesh elements necessitates development of data access tools that can handle both spatial and temporal datasets. This paper presents an open-source, platform independent, tightly coupled GIS and distributed hydrologic modeling framework, \\{PIHMgis\\} (www.pihm.psu.edu), to improve model-data integration. Tight coupling is achieved through the development of an integrated user interface with an underlying shared geodata model, which improves data flow between the \\{PIHMgis\\} data processing components. The capability and effectiveness of the \\{PIHMgis\\} framework in providing functionalities for watershed delineation, domain decomposition, parameter assignment, simulation, visualization and analyses, is demonstrated through prototyping of a model simulation. The framework and the approach are applicable for watersheds of varied sizes, and offer a template for future GIS-Model integration efforts.

Gopal Bhatt; Mukesh Kumar; Christopher J. Duffy

2014-01-01T23:59:59.000Z

47

Processes Coupling the Upper and Deep Ocean on the Continental Slope D. Randolph Watts  

E-Print Network [OSTI]

Processes Coupling the Upper and Deep Ocean on the Continental Slope D. Randolph Watts Graduate / modeling) approach requires a combination of expertise from R. Watts, G. Sutyrin, and I. Ginis (who have in a published journal article (Logoutov, Sutyrin and Watts, 2001). These results are being used by Ginis

Rhode Island, University of

48

Method of processing materials using an inductively coupled plasma  

DOE Patents [OSTI]

A method of processing materials. The invention enables ultrafine, ultrapure powders to be formed from solid ingots in a gas free environment. A plasma is formed directly from an ingot which insures purity. The vaporized material is expanded through a nozzle and the resultant powder settles on a cold surface. An inductively coupled plasma may also be used to process waste chemicals. Noxious chemicals are directed through a series of plasma tubes, breaking molecular bonds and resulting in relatively harmless atomic constituents. 3 figs.

Hull, D.E.; Bieniewski, T.M.

1987-04-13T23:59:59.000Z

49

Coupled Model for Heat and Water Transport in a High Level Waste Repository  

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

Coupled Model for Heat and Water Transport in a High Level Waste Coupled Model for Heat and Water Transport in a High Level Waste Repository in Salt Coupled Model for Heat and Water Transport in a High Level Waste Repository in Salt This report summarizes efforts to simulate coupled thermal-hydrological-chemical (THC) processes occurring within a generic hypothetical high-level waste (HLW) repository in bedded salt; chemical processes of the system allow precipitation and dissolution of salt with elevated temperatures that drive water and water vapor flow around hot waste packages. Characterizing salt backfill processes is an important objective of the exercise. An evidence-based algorithm for mineral dehydration is also applied in the modeling. The Finite Element Heat and Mass transfer code (FEHM) is used to simulate coupled thermal,

50

A preferential vibration dissociation coupling model for nonequilibrium hypersonic flowfields  

E-Print Network [OSTI]

A preferential vibration-dissociation coupling model is incorporated into a radiatively coupled viscous shock layer code that also includes chemical, radiative, and thermal nonequilibrium. Stagnation point flow profiles are obtained for several...

McGough, David Earl

2012-06-07T23:59:59.000Z

51

A feature model of coupling technologies for Earth System Models  

Science Journals Connector (OSTI)

Couplers that link together two or more numerical simulations are well-known abstractions in the Earth System Modeling (ESM) community. In the past decade, reusable software assets have emerged to facilitate scientists in implementing couplers. While there is a large amount of overlap in the features supported by software coupling technologies, their implementations differ significantly in terms of both functional and non-functional properties. Using a domain analysis method called feature analysis, we explore the spectrum of features supported by coupling technologies used to build today's production ESMs.

Rocky Dunlap; Spencer Rugaber; Leo Mark

2013-01-01T23:59:59.000Z

52

Coupling a hydrogen production process to a nuclear reactor  

Science Journals Connector (OSTI)

Work is currently underway to define a pre-conceptual design of a hydrogen production plant. The reference case is a VHTR dedicated to hydrogen production using the sulphur-iodine process. The chemical part of the plant is based on a very detailed flow-sheet where all components are listed. Considering the volume and flow-rates of the circulating products, a detailed image of the chemical plant is drawn with several shops in parallel. A coupling circuit using gases was also studied with two intermediate heat exchangers at very high temperature. A specific heat transfer circuit is added inside the chemical part to distribute heat at the correct temperature. Optimisation of this circuit should lead to an increase in the overall efficiency of the process. Finally a methodology is proposed for the safety of the hydrogen production plant.

Pascal Anzieu; Patrick Aujollet; Dominique Barbier; Anne Bassi; Frederic Bertrand; Alain Le Duigou; Jean Leybros; Gilles Rodriguez

2008-01-01T23:59:59.000Z

53

Robust model-based fault diagnosis for chemical process systems  

E-Print Network [OSTI]

diagnosis systems, which use limited information about the process model to robustly detect, discriminate, and reconstruct instrumentation faults. Broadly, the proposed method consists of a novel nonlinear state and parameter estimator coupled with a fault...

Rajaraman, Srinivasan

2006-08-16T23:59:59.000Z

54

NOAH: A CSP-based language for describing the behaviour of coupled models  

Science Journals Connector (OSTI)

Scientists in many fields rely on computational simulations that are built from a collection of separate, inter-communicating single models (e.g. Earth System Models often consist of single models of the ocean, atmosphere and land processes); these simulations ... Keywords: CSP, FCA, automatic code generation, coupled modelling, deadlock

C. W. Armstrong; R. W. Ford; T. L. Freeman; G. D. Riley

2008-02-01T23:59:59.000Z

55

3457, Page, 1 Coupled CFD/Building Envelope Model  

E-Print Network [OSTI]

Performance Buildings Conference at Purdue, 2012 (Accepted) #12;3457, Page, 2 a standard model for a single3457, Page, 1 Coupled CFD/Building Envelope Model for the Purdue Living Lab Donghun KIM (kim1077 features. In the present case we develop a procedure for coupling a building envelope model to a CFD

Gugercin, Serkan

56

Computational Modeling of Conventionally Reinforced Concrete Coupling Beams  

E-Print Network [OSTI]

COMPUTATIONAL MODELING OF CONVENTIONALLY REINFORCED CONCRETE COUPLING BEAMS A Thesis by AJAY SESHADRI SHASTRI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of requirements... for the degree of MASTER OF SCIENCE December 2010 Major Subject: Civil Engineering Computational Modeling of Conventionally Reinforced Concrete Coupling Beams Copyright 2010...

Shastri, Ajay Seshadri

2012-02-14T23:59:59.000Z

57

Phenomenological band structure model of magnetic coupling in semiconductors  

E-Print Network [OSTI]

Phenomenological band structure model of magnetic coupling in semiconductors Gustavo M. Dalpian a,1­18]. Several models have been proposed to explain the phenomena, including the phenomenological Zener

Gong, Xingao

58

Time-Split versus Process-Split Coupling of Parameterizations and Dynamical Core  

Science Journals Connector (OSTI)

Simulations are compared to determine the effect of the details of the coupling of the parameterization suite with the dynamical core on the simulated climate. Simulations based on time-split and process-split couplings are compared to a ...

David L. Williamson

2002-08-01T23:59:59.000Z

59

Kinetic Modeling of Microbiological Processes  

SciTech Connect (OSTI)

Kinetic description of microbiological processes is vital for the design and control of microbe-based biotechnologies such as waste water treatment, petroleum oil recovery, and contaminant attenuation and remediation. Various models have been proposed to describe microbiological processes. This editorial article discusses the advantages and limiation of these modeling approaches in cluding tranditional, Monod-type models and derivatives, and recently developed constraint-based approaches. The article also offers the future direction of modeling researches that best suit for petroleum and environmental biotechnologies.

Liu, Chongxuan; Fang, Yilin

2012-09-17T23:59:59.000Z

60

Restore: Modeling Repair and Restoration Processes | Argonne...  

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

Restore: Modeling Repair and Restoration Processes Restore: Modeling Repair and Restoration Processes Argonne's Restore software models complex sets of steps required to accomplish...

Note: This page contains sample records for the topic "modeling coupled processes" 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

Amazon Deforestation and Climate Change in a Coupled Model Simulation  

Science Journals Connector (OSTI)

The effects of Amazon deforestation on climate change are investigated using twin numerical experiments of an atmospheric general circulation model (AGCM) with prescribed global sea surface temperature and the same AGCM coupled to an ocean GCM (...

Paulo Nobre; Marta Malagutti; Domingos F. Urbano; Roberto A. F. de Almeida; Emanuel Giarolla

2009-11-01T23:59:59.000Z

62

Why is the AMOC Monostable in Coupled General Circulation Models?  

Science Journals Connector (OSTI)

This paper is concerned with the question: why do coupled general circulation models (CGCM) seem to be biased toward a monostable Atlantic meridional overturning circulation (AMOC)? In particular, the authors investigate whether the monostable ...

Wei Liu; Zhengyu Liu; Esther C. Brady

2014-03-01T23:59:59.000Z

63

Coupled fluids model in FRW space-time  

E-Print Network [OSTI]

In this paper, we analyze a two coupled fluids model by investigating several solutions for accelerated universe in flat FRW space-time. One of the fluids can be identified with the matter and the model possesses the standard matter solution also. Beyond the removal of the coincidence problem, we will see how the coupling may change the description of the energy contents of the universe and which features can be aquired with respect to the standard decoupled cases.

Shynaray Myrzakul; Ratbay Myrzakulov; Lorenzo Sebastiani

2014-06-06T23:59:59.000Z

64

Coupled fluids model in FRW space-time  

E-Print Network [OSTI]

In this paper, we analyze a two coupled fluids model by investigating several solutions for accelerated universe in flat FRW space-time. One of the fluids can be identified with the matter and the model possesses the standard matter solution also. Beyond the removal of the coincidence problem, we will see how the coupling may change the description of the energy contents of the universe and which features can be aquired with respect to the standard decoupled cases.

Myrzakul, Shynaray; Sebastiani, Lorenzo

2014-01-01T23:59:59.000Z

65

Transtheoretical Model of Change with couples  

E-Print Network [OSTI]

The Transtheoretical Model of Change is intended to be a general model of change that can be applied to many populations and domains of change. However, most of the studies that have investigated this model have focused on addiction-related topics...

Schneider, William Joel

2004-09-30T23:59:59.000Z

66

Precision coupling system modelling based on rough set and support vector machine  

Science Journals Connector (OSTI)

This paper presents the results of a research into the use of rough set (RS) for the precision coupling system modelling based on support vector machine (SVM). Because of the impact of multiple geometric parameters, there are more input variables in the precision coupling system modelling process. The high-dimensional data poses an interesting challenge to machine learning, as the presence of large numbers of redundant or highly correlated variables can seriously degrade modelling accuracy. In this study, a modelling method was developed based on rough set and support vector machine for precision coupling system. We used RS as the pre-processor for precision coupling system modelling, so as to realise dimension reduction of the high-dimensional data and improve the predictive performance of machine learning method, and then SVM was used for precision coupling system modelling. Experiments were carried out on a typical precision coupling, hydraulic valve. The results show that the use of RS method can improve the performance of machine learning in the modelling of high-dimensional data.

Jian-wei Ma; Fu-ji Wang; Zhen-yuan Jia; Wei Liu

2013-01-01T23:59:59.000Z

67

Coupled Climate and Earth System Models  

Science Journals Connector (OSTI)

We are all familiar with weather forecasts that predict the local weather for the next few days. These are made using a high-resolution numerical model of the atmosphere, and sometimes extend out as far as 10 ...

Peter R. Gent

2012-01-01T23:59:59.000Z

68

Standard Model-like D-brane models and gauge couplings  

E-Print Network [OSTI]

We systematically search intersecting D-brane models, which just realize the Standard Model chiral matter contents and gauge symmetry. We construct new classes of non-supersymmetric Standard Model-like models. We also study gauge coupling constants of these models. The tree level gauge coupling is a function of compactification moduli, string scale, string coupling and winding number of D-branes. By tuning them, we examine whether the models can explain the experimental values of gauge couplings. As a result, we find that the string scale should be greater than $10^{14-15}$GeV if the compactification scale and the string scale are the same order.

Hamada, Yuta; Uemura, Shohei

2014-01-01T23:59:59.000Z

69

Standard Model-like D-brane models and gauge couplings  

E-Print Network [OSTI]

We systematically search intersecting D-brane models, which just realize the Standard Model chiral matter contents and gauge symmetry. We construct new classes of non-supersymmetric Standard Model-like models. We also study gauge coupling constants of these models. The tree level gauge coupling is a function of compactification moduli, string scale, string coupling and winding number of D-branes. By tuning them, we examine whether the models can explain the experimental values of gauge couplings. As a result, we find that the string scale should be greater than $10^{14-15}$GeV if the compactification scale and the string scale are the same order.

Yuta Hamada; Tatsuo Kobayashi; Shohei Uemura

2014-09-09T23:59:59.000Z

70

Model-free measure of coupling from embedding principle  

E-Print Network [OSTI]

A model-free measure of coupling between dynamical variables is built from time series embedding principle. The approach described does not require a mathematical form for the dynamics to be assumed. The approach also does not require density estimation which is an intractable problem in high dimensions. The measure has strict asymptotic bounds and is robust to noise. The proposed approach is used to demonstrate coupling between complex time series from the finance world.

Chetan Nichkawde

2014-02-17T23:59:59.000Z

71

Coupling climate models with the Earth System Modeling Framework and the Common Component Architecture  

Science Journals Connector (OSTI)

Typical Earth system models involve coupled model components in high-performance computing (HPC) environments. In the last few years, several frameworks have been developed for HPC applications. Two of them are component-based frameworks: the Earth System ... Keywords: climate model, framework, model coupling

S. J. Zhou

2006-02-01T23:59:59.000Z

72

Coupled spin models for magnetic variation of planets and stars  

Science Journals Connector (OSTI)

......The powers alpha are plotted in this diagram. The parameters lambda and mu are given...motivate our coupled spin model from general MHD. The element should have an inward-winding...applied the LCS model, supplemented with MHD equations, to other planets and satellites......

A. Nakamichi; H. Mouri; D. Schmitt; A. Ferriz-Mas; J. Wicht; M. Morikawa

2012-07-11T23:59:59.000Z

73

Coupled AtmosphereWildland Fire Modelling Jean Baptiste Filippi1  

E-Print Network [OSTI]

to the estimation of the rate of spread of the fire. Wildfire's convection (i.e., entire plume) can modify the local localized extreme events. These models have been selected because they can be run coupled and support model used in ForeFire provides a physical formulation to take into account the effect of wind and slope

Clements, Craig

74

High ethylene to ethane processes for oxidative coupling  

DOE Patents [OSTI]

Oxidative coupling of lower alkane to higher hydrocarbon is conducted using a catalyst comprising barium and/or strontium component and a metal oxide combustion promoter in the presence of vapor phase halogen component. High ethylene to ethane mole ratios in the product can be obtained over extended operating periods.

Chafin, R.B.; Warren, B.K.

1991-12-17T23:59:59.000Z

75

High ethylene to ethane processes for oxidative coupling  

DOE Patents [OSTI]

Oxidative coupling of lower alkane to higher hydrocarbon is conducted using catalyst comprising barium and/or strontium component and a metal oxide combustion promoter in the presence of vapor phase halogen component. High ethylene to ethane mole ratios in the product can be obtained over extended operating periods.

Chafin, Richard B. (Hurricane, WV); Warren, Barbara K. (Charleston, WV)

1991-01-01T23:59:59.000Z

76

Hybrid coupled models of the tropical Paci c | II ENSO prediction  

E-Print Network [OSTI]

Hybrid coupled models of the tropical Paci#12;c | II ENSO prediction by Youmin Tang 1 , William W: ytang@cims.nyu.edu #12; Abstract Two hybrid coupled models (HCMs), a dynamical ocean model coupled Introduction Models for ENSO prediction can be categorized into purely statistical models, hybrid coupled

Hsieh, William

77

Simulation of Coupled Processes of Flow, Transport, and Storage of CO2 in Saline Aquifers  

SciTech Connect (OSTI)

This report is the final scientific one for the award DE- FE0000988 entitled “Simulation of Coupled Processes of Flow, Transport, and Storage of CO2 in Saline Aquifers.” The work has been divided into six tasks. In task, “Development of a Three-Phase Non-Isothermal CO2 Flow Module,” we developed a fluid property module for brine-CO2 mixtures designed to handle all possible phase combinations of aqueous phase, sub-critical liquid and gaseous CO2, supercritical CO2, and solid salt. The thermodynamic and thermophysical properties of brine-CO2 mixtures (density, viscosity, and specific enthalpy of fluid phases; partitioning of mass components among the different phases) use the same correlations as an earlier fluid property module that does not distinguish between gaseous and liquid CO2-rich phases. We verified the fluid property module using two leakage scenarios, one that involves CO2 migration up a blind fault and subsequent accumulation in a secondary “parasitic” reservoir at shallower depth, and another investigating leakage of CO2 from a deep storage reservoir along a vertical fault zone. In task, “Development of a Rock Mechanical Module,” we developed a massively parallel reservoir simulator for modeling THM processes in porous media brine aquifers. We derived, from the fundamental equations describing deformation of porous elastic media, a momentum conservation equation relating mean stress, pressure, and temperature, and incorporated it alongside the mass and energy conservation equations from the TOUGH2 formulation, the starting point for the simulator. In addition, rock properties, namely permeability and porosity, are functions of effective stress and other variables that are obtained from the literature. We verified the simulator formulation and numerical implementation using analytical solutions and example problems from the literature. For the former, we matched a one-dimensional consolidation problem and a two-dimensional simulation of the Mandel-Cryer effect. For the latter, we obtained a good match of temperature and gas saturation profiles, and surface uplift, after injection of hot fluid into a model of a caldera structure. In task, “Incorporation of Geochemical Reactions of Selected Important Species,” we developed a novel mathematical model of THMC processes in porous and fractured saline aquifers, simulating geo-chemical reactions associated with CO2 sequestration in saline aquifers. Two computational frameworks, sequentially coupled and fully coupled, were used to simulate the reactions and transport. We verified capabilities of the THMC model to treat complex THMC processes during CO2 sequestration by analytical solutions and we constructed reactive transport models to analyze the THMC process quantitatively. Three of these are 1D reactive transport under chemical equilibrium, a batch reaction model with equilibrium chemical reactions, and a THMC model with CO2 dissolution. In task “Study of Instability in CO2 Dissolution-Diffusion-Convection Processes,” We reviewed literature related to the study of density driven convective flows and on the instability of CO2 dissolution-diffusion-convection processes. We ran simulations that model the density-driven flow instability that would occur during CO2 sequestration. CO2 diffused through the top of the system and dissolved in the aqueous phase there, increasing its density. Density fingers formed along the top boundary, and coalesced into a few prominent ones, causing convective flow that forced the fluid to the system bottom. These simulations were in two and three dimensions. We ran additional simulations of convective mixing with density contrast caused by variable dissolved CO2 concentration in saline water, modeled after laboratory experiments in which supercritical CO2 was circulated in the headspace above a brine saturated packed sand in a pressure vessel. As CO2 dissolved into the upper part of the saturated sand, liquid phase density increases causing instability and setting off convective mixing. We obtained good agreement

Wu, Yu-Shu; Chen, Zizhong; Kazemi, Hossein; Yin, Xiaolong; Pruess, Karsten; Oldenburg, Curt; Winterfeld, Philip; Zhang, Ronglei

2014-09-30T23:59:59.000Z

78

A Coupled Model Study on the Formation and Dissipation of Sea Fogs  

Science Journals Connector (OSTI)

This study examined the impact of air–sea coupling using a coupled atmosphere–ocean modeling system consisting of the Coupled Ocean–Atmosphere Mesoscale Prediction System as the atmospheric component and the Regional Ocean Modeling System as the ...

Ki-Young Heo; Kyung-Ja Ha

2010-04-01T23:59:59.000Z

79

MODELLING OF CONCRETE STRUCTURES AFFECTED BY INTERNAL SWELLING REACTIONS: COUPLINGS BETWEEN  

E-Print Network [OSTI]

, France Abstract Alkali Aggregate Reaction (AAR) and Delayed Ettringite Formation (DEF) cause expansion Ettringite Formation, Modelling, Coupling 1. INTRODUCTION Alkali Aggregate Reaction (AAR) and Delayed Ettringite Formation (DEF) are both Internal Swelling Processes (ISP) that can affect concrete. In the first

Paris-Sud XI, Université de

80

Coupled numerical modelling of power loss generation in busbar system of low-voltage switchgear  

Science Journals Connector (OSTI)

Abstract This paper presents a coupled mathematical model of the heat transfer processes in an electric switchgear. The considered problem required the computation of the detailed distribution of the power losses and all the heat transfer modes (radiation, convection, and conduction) within a unit. In this complex thermal analysis, different definitions of electric busbar heating were considered and compared. The most advanced model, which couples the thermal and electromagnetic fields in two ways, was also compared with the simplified approaches. First, the direct current loading of the busbar, which neglected the alternating current effects, was considered. Second, models that included only one method of coupling were calculated for different assumed average busbar temperatures. Finally, the model with the two-way coupling, which took the eddy currents and proximity effects into account, was simulated using an iteration loop between the electromagnetic and fluid flow solvers. This study employed a geometrical model of industrial low-voltage switchgear. The presented mathematical model was also validated against temperature measurements carried out by a certified laboratory. The obtained results show that a fully coupled model produces very satisfactory agreement between computed and experimental data.

Mateusz Bedkowski; Jacek Smolka; Krzysztof Banasiak; Zbigniew Bulinski; Andrzej J. Nowak; Tomasz Tomanek; Adam Wajda

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

Modelling and Control of Activated Sludge Processes  

E-Print Network [OSTI]

Modelling and Control of Activated Sludge Processes Michela Mulas Dottorato di Ricerca of Activated Sludge Processes Michela Mulas Supervisors: Prof. Roberto Baratti Ing. Stefania Tronci Dottorato . . . . . . . . . . . . . . . . . . . . . . . . . 5 2 ASP Models and Simulations 7 2.1 The Activated Sludge Process

Skogestad, Sigurd

82

Numerical Modeling of Thermal EOR: Comprehensive Coupling of an AMR-Based Model  

E-Print Network [OSTI]

Numerical Modeling of Thermal EOR: Comprehensive Coupling of an AMR-Based Model of Thermal Fluid.renard@ifpen.fr * Corresponding author Résumé -- Modélisation numérique d'EOR thermique : couplage complet entre un modèle d of Thermal EOR: Comprehensive Coupling of an AMR-Based Model of Thermal Fluid Flow and Geomechanics

Paris-Sud XI, Université de

83

Queueing up for enzymatic processing: Correlated signaling through coupled degradation  

E-Print Network [OSTI]

J. Williams, Lev S. Tsimring, Jeff Hasty SBML Model The SBML file of the model used for this study (Supplementary Information) Natalie A. Cookson, William H. Mather, Tal Danino, Octavio Mondrag´on-Palomino, Ruth

84

Thin film coating process using an inductively coupled plasma  

DOE Patents [OSTI]

Thin coatings of normally solid materials are applied to target substrates using an inductively coupled plasma. Particles of the coating material are vaporized by plasma heating, and pass through an orifice to a first vacuum zone in which the particles are accelerated to a velocity greater than Mach 1. The shock wave generated in the first vacuum zone is intercepted by the tip of a skimmer cone that provides a second orifice. The particles pass through the second orifice into a second zone maintained at a higher vacuum and impinge on the target to form the coating. Ultrapure coatings can be formed.

Kniseley, Richard N. (Ames, IA); Schmidt, Frederick A. (Ames, IA); Merkle, Brian D. (Ames, IA)

1990-01-30T23:59:59.000Z

85

Electromagnetically induced transparency from two-phonon processes in quadratically coupled membranes  

SciTech Connect (OSTI)

We describe how electromagnetically induced transparency can arise in quadratically coupled optomechanical systems. Due to quadratic coupling, the underlying optical process involves a two-phonon process in an optomechanical system, and this two-phonon process makes the mean displacement, which plays the role of atomic coherence in traditional electromagnetically induced transparency (EIT), zero. We show how the fluctuation in displacement can play a role similar to atomic coherence and can lead to EIT-like effects in quadratically coupled optomechanical systems. We show how such effects can be studied using the existing optomechanical systems.

Huang, Sumei; Agarwal, G. S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2011-02-15T23:59:59.000Z

86

Coupling schemes for modeling hydraulic fracture propagation using the XFEM  

E-Print Network [OSTI]

Coupling schemes for modeling hydraulic fracture propagation using the XFEM Elizaveta Gordeliy of hydraulic fractures in an elastic medium. With appropriate enrichment, the XFEM resolves the Neumann(h) accuracy. For hydraulic fracture problems with a lag separating the uid front from the fracture front, we

Peirce, Anthony

87

Coupling Multi-Component Models with MPH on Distributed Memory Computer Architectures  

E-Print Network [OSTI]

Among these, NASA’s Earth System Models Framework (ESMF) [to facilitate coupling earth system model components and to

He, Yun; Ding, Chris

2005-01-01T23:59:59.000Z

88

Explosive shock processing of Pr2Fe14B/ Fe exchange-coupled nanocomposite bulk magnets  

E-Print Network [OSTI]

Explosive shock processing of Pr2Fe14B/ ­Fe exchange-coupled nanocomposite bulk magnets Z.Q. Jin between neigh- boring magnetic phases.1,2 The prerequisite for effective exchange coupling is a small are usually used to produce single-phase microcrystalline permanent magnets, are not favored in making bulk

Liu, J. Ping

89

Processes Coupling the Upper and Deep Ocean on the Continental Slope D. Randolph Watts  

E-Print Network [OSTI]

Processes Coupling the Upper and Deep Ocean on the Continental Slope D. Randolph Watts Graduate-pronged approach has required a combination of expertise from R. Watts, G. Sutyrin, and I. Ginis (who have

Rhode Island, University of

90

Processes Coupling the Upper and Deep Ocean on the Continental Slope D. Randolph Watts  

E-Print Network [OSTI]

Processes Coupling the Upper and Deep Ocean on the Continental Slope D. Randolph Watts Graduate of expertise from R. Watts, G. Sutyrin, and I. Ginis (who have a coordinated ONR-supported study at URI

Rhode Island, University of

91

Ising Model Coupled to Three-Dimensional Quantum Gravity  

E-Print Network [OSTI]

We have performed Monte Carlo simulations of the Ising model coupled to three-dimensional quantum gravity based on a summation over dynamical triangulations. These were done both in the microcanonical ensemble, with the number of points in the triangulation and the number of Ising spins fixed, and in the grand canoncal ensemble. We have investigated the two possible cases of the spins living on the vertices of the triangulation (``diect'' case) and the spins living in the middle of the tetrahedra (``dual'' case). We observed phase transitions which are probably second order, and found that the dual implementation more effectively couples the spins to the quantum gravity.

C. F. Baillie

1992-05-09T23:59:59.000Z

92

Constraints on Top Couplings in Models with Exotic Quarks  

Science Journals Connector (OSTI)

The extension of the standard model with exotic quark singlets and doublets introduces large flavor changing neutral couplings between ordinary fermions. We derive inequalities which translate the precise determination of the diagonal Z couplings, in particular, at LEP, into stringent bounds on the off-diagonal ones. The resulting limits can be saturated in minimal extensions with one vector doublet or singlet. In this case, 23 and 6 single top events, respectively, are predicted at LEP2 for an integrated luminosity of 500 pb-1 per experiment.

F. del Aguila; J. A. Aguilar-Saavedra; R. Miquel

1999-02-22T23:59:59.000Z

93

Computational battery dynamics (CBD)--electrochemical/thermal coupled modeling and multi-scale modeling  

E-Print Network [OSTI]

Computational battery dynamics (CBD)--electrochemical/thermal coupled modeling and multi the development of first-principles based mathematical models for batteries developed on a framework parallel to computation fluid dynamics (CFD), herein termed computational battery dynamics (CBD). This general

94

Coupling the High Complexity Land Surface Model ACASA to the Mesoscale Model WRF  

E-Print Network [OSTI]

In this study, the Weather Research and Forecasting Model (WRF) is coupled with the Advanced Canopy-Atmosphere-Soil Algorithm (ACASA), a high complexity land surface model. Although WRF is a state-of-the-art regional ...

Xu, L.

95

Coupling Lattice Boltzmann and Molecular Dynamics models for dense fluids  

E-Print Network [OSTI]

We propose a hybrid model, coupling Lattice Boltzmann and Molecular Dynamics models, for the simulation of dense fluids. Time and length scales are decoupled by using an iterative Schwarz domain decomposition algorithm. The MD and LB formulations communicate via the exchange of velocities and velocity gradients at the interface. We validate the present LB-MD model in simulations of flows of liquid argon past and through a carbon nanotube. Comparisons with existing hybrid algorithms and with reference MD solutions demonstrate the validity of the present approach.

A. Dupuis; E. M. Kotsalis; P. Koumoutsakos

2006-10-27T23:59:59.000Z

96

Coupling Air Flow Models to Load/Energy Models and Implications for  

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

Coupling Air Flow Models to Load/Energy Models and Implications for Coupling Air Flow Models to Load/Energy Models and Implications for Envelope Component Testing and Modeling Speaker(s): Brent Griffith Date: July 30, 2002 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Dariush Arasteh Air models allow accounting for air temperature variations within a thermal zone or along the surface of an envelope component. A recently completed ASHRAE research project (RP-1222) produced a source code toolkit focused on coupling airflow models to load routines typical of whole building energy simulation. The two modeling domains are computed separately (and iteratively) with relevant temperature boundary conditions passed back and forth. One of the air models in the toolkit is a new contribution to crude/fast airflow modeling that is based on solving the Euler equation

97

Coupled-Channels Quantum Theory of Electronic Flux Density in Electronically Adiabatic Processes: Fundamentals  

Science Journals Connector (OSTI)

Coupled-Channels Quantum Theory of Electronic Flux Density in Electronically Adiabatic Processes: Fundamentals ... One’s understanding of the mechanism of this fundamental reaction, as well as those of other arguably more important electronically adiabatic processes, should be significantly advanced by a knowledge of the electronic flux density (je). ...

D. J. Diestler

2011-11-21T23:59:59.000Z

98

A feature model of coupling technologies for Earth System Models  

Science Journals Connector (OSTI)

Couplers that link together two or more numerical simulations are well-known abstractions in the Earth System Modeling (ESM) community. In the past decade, reusable software assets have emerged to facilitate scientists in implementing couplers. While ... Keywords: Climate model, Code generation, Coupler, Feature analysis, Software architecture

Rocky Dunlap; Spencer Rugaber; Leo Mark

2013-04-01T23:59:59.000Z

99

Quantum Jump Approach to Switching Process of a Josephson Junction Coupled to a Microscopic Two-Level System  

E-Print Network [OSTI]

With microwave irradiation, the switching current of a Josephson junction coupled to a microscopic two-level system jumps randomly between two discrete states. We modeled the switching process of the coupled system with quantum jump approach that was generally used in quantum optics. The parameters that affect the character of the quantum jumps between macroscopic quantum states are discussed. The results obtained from our theoretical analysis agree well with those of the experiments and provide a clear physical picture for the macroscopic quantum jumps in Josephson junctions coupled with two-level systems. In addition, quantum jumps may serve as a useful tool to investigate the microscopic two-level structures in solid-state systems.

Xueda Wen; Yiwen Wang; Ning Dong; Guozhu Sun; Jian Chen; Lin Kang; Weiwei Xu; Peiheng Wu; Yang Yu

2009-07-14T23:59:59.000Z

100

Thermodynamics of the BMN matrix model at strong coupling  

E-Print Network [OSTI]

We construct the black hole geometry dual to the deconfined phase of the BMN matrix model at strong 't Hooft coupling. We approach this solution from the limit of large temperature where it is approximately that of the non-extremal D0-brane geometry with a spherical $S^8$ horizon. This geometry preserves the $SO(9)$ symmetry of the matrix model trivial vacuum. As the temperature decreases the horizon becomes deformed and breaks the $SO(9)$ to the $SO(6)\\times SO(3)$ symmetry of the matrix model. When the black hole free energy crosses zero the system undergoes a phase transition to the confined phase described by a Lin-Maldacena geometry. We determine this critical temperature, whose computation is also within reach of Monte Carlo simulations of the matrix model.

Costa, Miguel S; Penedones, Joao; Santos, Jorge

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

Modeling the overcharge process of VRLA batteries , G.Q. Wang, C.Y. Wang*  

E-Print Network [OSTI]

-phase, electrochemical and thermal coupled model is developed for valve-regulated lead�acid (VRLA) batteries. Physical process with the battery model so that one can predict both electrochemical and thermal behaviors underModeling the overcharge process of VRLA batteries W.B. Gu1 , G.Q. Wang, C.Y. Wang* Department

102

MJO and Convectively Coupled Equatorial Waves Simulated by CMIP5 Climate Models  

Science Journals Connector (OSTI)

This study evaluates the simulation of the Madden–Julian oscillation (MJO) and convectively coupled equatorial waves (CCEWs) in 20 models from the Coupled Model Intercomparison Project (CMIP) phase 5 (CMIP5) in the Intergovernmental Panel on ...

Meng-Pai Hung; Jia-Lin Lin; Wanqiu Wang; Daehyun Kim; Toshiaki Shinoda; Scott J. Weaver

2013-09-01T23:59:59.000Z

103

Coupled processes in single fractures, double fractures and fractured porous media  

SciTech Connect (OSTI)

The emplacement of a nuclear waste repository in a fractured porous medium provides a heat source of large dimensions over an extended period of time. It also creates a large cavity in the rock mass, changing significantly the stress field. Such major changes induce various coupled thermohydraulic, hydromechanic and hydrochemical transport processes in the environment around a nuclear waste repository. The present paper gives, first, a general overview of the coupled processes involving thermal, mechanical, hydrological and chemical effects. Then investigations of a number of specific coupled processes are described in the context of fluid flow and transport in a single fracture, two intersecting fractures and a fractured porous medium near a nuclear waste repository. The results are presented and discussed.

Tsang, C.F.

1986-12-01T23:59:59.000Z

104

Evergreening Peer Review Business Process Modeling (BPM)  

E-Print Network [OSTI]

Evergreening Peer Review Business Process Modeling (BPM) On behalf of the Peer Review Subject of the BPM process undertaken to model the current business process of peer review from the perspective. Sheryl K. Brining, Ph.D. Michael Rennolds Paul Sheehy, Ph.D. #12;Peer Review BPM White Paper-Dec1_FINAL

Rau, Don C.

105

Coupled-Channel Models of Direct-Semidirect Capture via Giant-Dipole Resonances  

SciTech Connect (OSTI)

Semidirect capture, a two-step process that excites a giant-dipole resonance followed by its radiative de-excitation, is a dominant process near giant-dipole resonances, that is, for incoming neutron energies within 5 20 MeV. At lower energies such processes may affect neutron capture rates that are relevant to astrophysical nucleosynthesis models. We implement a semidirect capture model in the coupled-channel reaction code Fresco and validate it by comparing the cross section for direct-semidirect capture 208Pb(n,g)209Pb to experimental data. We also investigate the effect of low-energy electric dipole strength in the pygmy resonance. We use a conventional single-particle direct-semidirect capture code Cupido for comparison. Furthermore, we present and discuss our results for direct-semidirect capture reaction 130Sn(n,g)131Sn, the cross section of which is known to have a significant effect on nucleosynthesis models.

Thompson, I J [Lawrence Livermore National Laboratory (LLNL)] [Lawrence Livermore National Laboratory (LLNL); Escher, Jutta E [ORNL] [ORNL; Arbanas, Goran [ORNL] [ORNL

2013-01-01T23:59:59.000Z

106

Coupled-Channel Models of Direct-Semidirect Capture via Giant-Dipole Resonances  

Science Journals Connector (OSTI)

Abstract Semidirect capture, a two-step process that excites a giant-dipole resonance followed by its radiative de-excitation, is a dominant process near giant-dipole resonances, that is, for incoming neutron energies within 5–20 MeV. At lower energies such processes may affect neutron capture rates that are relevant to astrophysical nucleosynthesis models. We implement a semidirect capture model in the coupled-channel reaction code Fresco and validate it by comparing the cross section for direct-semidirect capture 208Pb(n,?)209Pb to experimental data. We also investigate the effect of low-energy electric dipole strength in the pygmy resonance. We use a conventional single-particle direct-semidirect capture code Cupido for comparison. Furthermore, we present and discuss our results for direct-semidirect capture reaction 130Sn(n,?)131Sn, the cross section of which is known to have a significant effect on nucleosynthesis models.

I.J. Thompson; J.E. Escher; G. Arbanas

2014-01-01T23:59:59.000Z

107

Analysis of Dynamic Behavior of a Thermally Coupled Distillation Column Implemented on a Process with Recycles  

Science Journals Connector (OSTI)

Abstract Nowadays, the installation and operation of systems with minimum energy and material consumption is a main objective in the industrial ambit; this goal can be achieved through the implementation of recycle streams to recover raw materials and the use of energy integration techniques to minimize utilities requirements. However, when a process is highly integrated, e.g. processes with recycle streams and energy integration or thermal couplings, systems can present control problems. Several studies for Reactor-Separation-Recycle (RSR) systems using separation systems with conventional distillation columns have been reported, but few works have focused on energy-integrated columns or thermally coupled distillation sequences. This work presents a comparison between the dynamic behavior of a thermally coupled distillation column with side rectifier implemented within a RSR system and that obtained with a conventional distillation sequence.

D. Mascote-Pérez; A. Sánchez-Hijar; N. Ramírez-Corona; A. Jiménez-Gutierrez

2012-01-01T23:59:59.000Z

108

Correlation Functions in the Multiple Ising Model Coupled to Gravity  

E-Print Network [OSTI]

The model of p Ising spins coupled to 2d gravity, in the form of a sum over planar phi-cubed graphs, is studied and in particular the two-point and spin-spin correlation functions are considered. We first solve a toy model in which only a partial summation over spin configurations is performed and, using a modified geodesic distance, various correlation functions are determined. The two-point function has a diverging length scale associated with it. The critical exponents are calculated and it is shown that all the standard scaling relations apply. Next the full model is studied, in which all spin configurations are included. Many of the considerations for the toy model apply for the full model, which also has a diverging geometric correlation length associated with the transition to a branched polymer phase. Using a transfer function we show that the two-point and spin-spin correlation functions decay exponentially with distance. Finally, by assuming various scaling relations, we make a prediction for the critical exponents at the transition between the magnetized and branched polymer phases in the full model.

M. G. Harris; J. Ambjorn

1996-02-06T23:59:59.000Z

109

Bio-Optical Response and Coupling with Physical Processes in the Lombok Strait Region  

E-Print Network [OSTI]

Bio-Optical Response and Coupling with Physical Processes in the Lombok Strait Region Burton H.boss@maine.edu ABSTRACT The optical structure and variability of the Lombok Straits region is poorly understood, but available remotely sensed ocean color indicates that there is a strong optical response and signal

Boss, Emmanuel S.

110

Image Processing with Manifold Models  

E-Print Network [OSTI]

to the following signals ensemble def. = {x f(x) = A(x) cos((x)) \\ ||A || Amax and || || max.} This model to = R+ Ã? R+ Ã? S1 . The projection of a patch p L2 ([-/2, /2]) on M can be carried over approximately] and defines the windowed Fourier 20 = {x f(x) = A(x) cos((x)) \\ ||A || Amax and || || max.} model of locally

Milanfar, Peyman

111

Performance evaluation of artificial neural network coupled with generic algorithm and response surface methodology in modeling and optimization of biodiesel production process parameters from shea tree (Vitellaria paradoxa) nut butter  

Science Journals Connector (OSTI)

Abstract This work investigated the potential of shea butter oil (SBO) as feedstock for synthesis of biodiesel. Due to high free fatty acid (FFA) of SBO used, response surface methodology (RSM) was employed to model and optimize the pretreatment step while its conversion to biodiesel was modeled and optimized using RSM and artificial neural network (ANN). The acid value of the SBO was reduced to 1.19 mg KOH/g with oil/methanol molar ratio of 3.3, H2SO4 of 0.15 v/v, time of 60 min and temperature of 45 °C. Optimum values predicted for the transesterification reaction by RSM were temperature of 90 °C, KOH of 0.6 w/v, oil/methanol molar ratio of 3.5, and time of 30 min with actual shea butter oil biodiesel (SBOB) yield of 99.65% (w/w). ANN combined with generic algorithm gave the optimal condition as temperature of 82 °C, KOH of 0.40 w/v, oil/methanol molar ratio of 2.62 and time of 30 min with actual SBOB yield of 99.94% (w/w). Coefficient of determination (R2) and absolute average deviation (AAD) of the models were 0.9923, 0.83% (RSM) and 0.9991, 0.15% (ANN), which demonstrated that ANN model was more efficient than RSM model. Properties of SBOB produced were within biodiesel standard specifications.

Eriola Betiku; Samuel S. Okunsolawo; Sheriff O. Ajala; Olatunde S. Odedele

2015-01-01T23:59:59.000Z

112

BUSINESS PROCESS MODELING TOWARDS DATA QUALITY ASSURANCE  

E-Print Network [OSTI]

BUSINESS PROCESS MODELING TOWARDS DATA QUALITY ASSURANCE An Organizational Engineering Approach Keywords: Data Quality, Business Processes, Object-Oriented Modeling, UML Abstract: Data is produced and consumed everyday by information systems, and its inherent quality is a fundamental aspect to operational

113

The Climatology and Interannual Variability of East Asian Summer Monsoon in CMIP5 Coupled Models: Does Air–Sea Coupling Improve the Simulations?  

Science Journals Connector (OSTI)

The climatology and interannual variability of the East Asian summer monsoon (EASM) simulated by 34 coupled general circulation models (CGCMs) from phase 5 of the Coupled Model Intercomparison Project (CMIP5) are evaluated. To estimate the role of ...

Fengfei Song; Tianjun Zhou

2014-12-01T23:59:59.000Z

114

Coupled Boltzmann computation of mixed axion neutralino dark matter in the SUSY DFSZ axion model  

E-Print Network [OSTI]

The supersymmetrized DFSZ axion model is highly motivated not only because it offers solutions to both the gauge hierarchy and strong CP problems, but also because it provides a solution to the SUSY mu problem which naturally allows for a Little Hierarchy. We compute the expected mixed axion-neutralino dark matter abundance for the SUSY DFSZ axion model in two benchmark cases-- a natural SUSY model with a standard neutralino underabundance (SUA) and an mSUGRA/CMSSM model with a standard overabundance (SOA). Our computation implements coupled Boltzmann equations which track the radiation density along with neutralino, axion (produced thermally (TH) and via coherent oscillations (CO)), saxion (TH- and CO-produced), axino and gravitino densities. In the SUSY DFSZ model, axions, axinos and saxions go through the process of freeze-in-- in contrast to freeze-out or out-of-equilibrium production as in the SUSY KSVZ model-- resulting in thermal yields which are largely independent of the re-heat temperature. We find the SUA case with suppressed saxion-axion couplings (\\xi=0) only admits solutions for PQ breaking scale f_a~radiation or violation of BBN constraints. An exception occurs at very large f_a~ 10^{15}-10^{16} GeV where large entropy dilution from CO-produced saxions leads to allowed models.

Kyu Jung Bae; Howard Baer; Andre Lessa; Hasan Serce

2014-06-16T23:59:59.000Z

115

INTEGRATED FISCHER TROPSCH MODULAR PROCESS MODEL  

SciTech Connect (OSTI)

With declining petroleum reserves, increased world demand, and unstable politics in some of the world’s richest oil producing regions, the capability for the U.S. to produce synthetic liquid fuels from domestic resources is critical to national security and economic stability. Coal, biomass and other carbonaceous materials can be converted to liquid fuels using several conversion processes. The leading candidate for large-scale conversion of coal to liquid fuels is the Fischer Tropsch (FT) process. Process configuration, component selection, and performance are interrelated and dependent on feed characteristics. This paper outlines a flexible modular approach to model an integrated FT process that utilizes a library of key component models, supporting kinetic data and materials and transport properties allowing rapid development of custom integrated plant models. The modular construction will permit rapid assessment of alternative designs and feed stocks. The modeling approach consists of three thrust areas, or “strands” – model/module development, integration of the model elements into an end to end integrated system model, and utilization of the model for plant design. Strand 1, model/module development, entails identifying, developing, and assembling a library of codes, user blocks, and data for FT process unit operations for a custom feedstock and plant description. Strand 2, integration development, provides the framework for linking these component and subsystem models to form an integrated FT plant simulation. Strand 3, plant design, includes testing and validation of the comprehensive model and performing design evaluation analyses.

Donna Post Guillen; Richard Boardman; Anastasia M. Gribik; Rick A. Wood; Robert A. Carrington

2007-12-01T23:59:59.000Z

116

Modeling inductively coupled plasmas: The coil current boundary condition  

Science Journals Connector (OSTI)

In modeling inductively coupled plasmas the boundary condition for the electromagnetic field equations can be treated by specifying either the current in the induction coil or the total power dissipated in the plasma. This paper presents a method for using the coil current boundary condition. An advantage of using the coil current boundary condition is that coil current unlike plasma power dissipation is easily measured; in this approach the plasma power dissipation is an outcome of the calculation. The results of sample calculations are presented covering a range of coil currents from 59 to 110 A. The conditions of the calculations correspond to experimental argon plasmas at atmospheric pressure and at 3.0 MHz frequency. The calculated isotherms are in good qualitative agreement with photographs of the laboratory plasmas.

Benjamin W. Yu; Steven L. Girshick

1991-01-01T23:59:59.000Z

117

Coupling a Transient Solvent Extraction Module with the Separations and Safeguards Performance Model  

SciTech Connect (OSTI)

A past difficulty in safeguards design for reprocessing plants is that no code existed for analysis and evaluation of the design. A number of codes have been developed in the past, but many are dated, and no single code is able to cover all aspects of materials accountancy, process monitoring, and diversion scenario analysis. The purpose of this work was to integrate a transient solvent extraction simulation module developed at Oak Ridge National Laboratory, with the SSPM Separations and Safeguards Performance Model, developed at Sandia National Laboratory, as a first step toward creating a more versatile design and evaluation tool. The SSPM was designed for materials accountancy and process monitoring analyses, but previous versions of the code have included limited detail on the chemical processes, including chemical separations. The transient solvent extraction model is based on the ORNL SEPHIS code approach to consider solute build up in a bank of contactors in the PUREX process. Combined, these capabilities yield a much more robust transient separations and safeguards model for evaluating safeguards system design. This coupling and the initial results are presented. In addition, some observations toward further enhancement of separations and safeguards modeling based on this effort are provided, including: items to be addressed in integrating legacy codes, additional improvements needed for a fully functional solvent extraction module, and recommendations for future integration of other chemical process modules.

de Almeida, Valmor F [ORNL; Birdwell Jr, Joseph F [ORNL; DePaoli, David W [ORNL; Gauld, Ian C [ORNL

2009-10-01T23:59:59.000Z

118

Coupling a transient solvent extraction module with the separations and safeguards performance model.  

SciTech Connect (OSTI)

A number of codes have been developed in the past for safeguards analysis, but many are dated, and no single code is able to cover all aspects of materials accountancy, process monitoring, and diversion scenario analysis. The purpose of this work was to integrate a transient solvent extraction simulation module developed at Oak Ridge National Laboratory, with the Separations and Safeguards Performance Model (SSPM), developed at Sandia National Laboratory, as a first step toward creating a more versatile design and evaluation tool. The SSPM was designed for materials accountancy and process monitoring analyses, but previous versions of the code have included limited detail on the chemical processes, including chemical separations. The transient solvent extraction model is based on the ORNL SEPHIS code approach to consider solute build up in a bank of contactors in the PUREX process. Combined, these capabilities yield a more robust transient separations and safeguards model for evaluating safeguards system design. This coupling and initial results are presented. In addition, some observations toward further enhancement of separations and safeguards modeling based on this effort are provided, including: items to be addressed in integrating legacy codes, additional improvements needed for a fully functional solvent extraction module, and recommendations for future integration of other chemical process modules.

DePaoli, David W. (Oak Ridge National Laboratory, Oak Ridge, TN); Birdwell, Joseph F. (Oak Ridge National Laboratory, Oak Ridge, TN); Gauld, Ian C. (Oak Ridge National Laboratory, Oak Ridge, TN); Cipiti, Benjamin B.; de Almeida, Valmor F. (Oak Ridge National Laboratory, Oak Ridge, TN)

2009-10-01T23:59:59.000Z

119

Parallel map projection of vector-based big spatial data: Coupling cloud computing with graphics processing units  

Science Journals Connector (OSTI)

Abstract The objective of this article is to present a framework that couples cloud and high-performance computing for the parallel map projection of vector-based big spatial data. The past few years have witnessed a tremendous growth of a variety of high-volume spatial data—i.e., big spatial data. Map projection is often needed, for example, when we apply these big spatial data into large-scale spatial analysis and modeling approaches that require a common coordinate system. However, due to the size of these data and algorithmic complexity of map projections, the transformation of big spatial data between alternative projections represents a pressing computational challenge. Recent advancement in cloud computing and high-performance computing offers a potential means of addressing this computational challenge. The parallel map projection framework presented in this study is based on a layered architecture that couples capabilities of cloud computing and high-performance computing accelerated by Graphics Processing Units. We use large LiDAR data as an example of vector-based big spatial data to investigate the utility of the parallel map projection framework. As experimental results reveal, the framework provides considerable acceleration for re-projecting vector-based big spatial data. Coupling high-performance and cloud computing, which complement to each other, is a suggested solution for the efficient processing and analysis of big spatial data.

Wenwu Tang; Wenpeng Feng

2014-01-01T23:59:59.000Z

120

Modeling Coupled Evaporation and Seepage in Ventilated Cavities  

SciTech Connect (OSTI)

Cavities excavated in unsaturated geological formations are important to activities such as nuclear waste disposal and mining. Such cavities provide a unique setting for simultaneous occurrence of seepage and evaporation. Previously, inverse numerical modeling of field liquid-release tests and associated seepage into cavities were used to provide seepage-related large-scale formation properties by ignoring the impact of evaporation. The applicability of such models was limited to the narrow range of ventilation conditions under which the models were calibrated. The objective of this study was to alleviate this limitation by incorporating evaporation into the seepage models. We modeled evaporation as an isothermal vapor diffusion process. The semi-physical model accounts for the relative humidity, temperature, and ventilation conditions of the cavities. The evaporation boundary layer thickness (BLT) over which diffusion occurs was estimated by calibration against free-water evaporation data collected inside the experimental cavities. The estimated values of BLT were 5 to 7 mm for the open underground drifts and 20 mm for niches closed off by bulkheads. Compared to previous models that neglected the effect of evaporation, this new approach showed significant improvement in capturing seepage fluctuations into open cavities of low relative humidity. At high relative-humidity values (greater than 85%), the effect of evaporation on seepage was very small.

T. Ghezzehei; R. Trautz; S. Finsterle; P. Cook; C. Ahlers

2004-07-01T23:59:59.000Z

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


121

Spheroidal close-coupling scheme to describe ionization processes in one-electron diatomic systems  

SciTech Connect (OSTI)

We propose a molecular close-coupling expansion in terms of prolate spheroidal wave functions confined in an ellipsoidal box. We first implement the method for ionization of H{sub 2}{sup +} molecular ions, by linearly polarized strong and short laser pulses, in the nonperturbative regime and within the (fixed nuclei) Born-Oppenheimer approximation. We further analyze the adequacy of the method to reproduce both the bound and the continuum nonadiabatic processes in ion-atom collisions.

Pons, B. [Centre Lasers Intenses et Applications, UMR 5107 du CNRS, Universite de Bordeaux-I, 351 Cours de la Liberation, F-33405 Talence (France)

2003-04-01T23:59:59.000Z

122

Modeling of Geothermal Reservoirs: Fundamental Processes, Computer  

Open Energy Info (EERE)

Page Page Edit with form History Facebook icon Twitter icon » Modeling of Geothermal Reservoirs: Fundamental Processes, Computer Simulation and Field Applications Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Modeling of Geothermal Reservoirs: Fundamental Processes, Computer Simulation and Field Applications Abstract This article attempts to critically evaluate the present state of the art of geothermal reservoir simulation. Methodological aspects of geothermal reservoir modeling are briefly reviewed, with special emphasis on flow in fractured media. We then examine some applications of numerical simulation to studies of reservoir dynamics, well test design and analysis, and modeling of specific fields. Tangible impacts of reservoir simulation

123

Pion photoproduction in a dynamical coupled-channels model  

E-Print Network [OSTI]

The charged and neutral pion photoproduction reactions are investigated in a dynamical coupled-channels approach based on the formulation of Haberzettl, Huang, and Nakayama [Phys. Rev. C 83, 065502 (2011)]. The hadronic final-state interaction is provided by the Juelich pi-N model, which includes the channels pi-N and eta-N comprising stable hadrons as well as the effective pi-pi-N channels pi-Delta, sigma-N, and rho-N. This hadronic model has been quite successful in describing pi-N to pi-N scattering for center-of-mass energies up to 1.9 GeV. By construction, the full pion photoproduction current satisfies the generalized Ward-Takahashi identity and thus is gauge invariant as a matter of course. The calculated differential cross sections and photon spin asymmetries up to 1.65 GeV center-of-mass energy for the reactions gamma p to pi+ n, gamma p to pi0 p, gamma n to pi- p and gamma n to pi0 n are in good agreement with the experimental data.

Huang, F; Haberzettl, H; Haidenbauer, J; Hanhart, C; Krewald, S; ner, U -G Meiß; Nakayama, K

2011-01-01T23:59:59.000Z

124

Pion photoproduction in a dynamical coupled-channels model  

E-Print Network [OSTI]

The charged and neutral pion photoproduction reactions are investigated in a dynamical coupled-channels approach based on the formulation of Haberzettl, Huang, and Nakayama [Phys. Rev. C 83, 065502 (2011)]. The hadronic final-state interaction is provided by the Juelich pi-N model, which includes the channels pi-N and eta-N comprising stable hadrons as well as the effective pi-pi-N channels pi-Delta, sigma-N, and rho-N. This hadronic model has been quite successful in describing pi-N to pi-N scattering for center-of-mass energies up to 1.9 GeV. By construction, the full pion photoproduction current satisfies the generalized Ward-Takahashi identity and thus is gauge invariant as a matter of course. The calculated differential cross sections and photon spin asymmetries up to 1.65 GeV center-of-mass energy for the reactions gamma p to pi+ n, gamma p to pi0 p, gamma n to pi- p and gamma n to pi0 n are in good agreement with the experimental data.

F. Huang; M. Döring; H. Haberzettl; J. Haidenbauer; C. Hanhart; S. Krewald; U. -G. Meiß ner; K. Nakayama

2011-10-17T23:59:59.000Z

125

Dirichlet Processes and Nonparametric Bayesian Modelling  

E-Print Network [OSTI]

;Statistical Approaches to Learning and Statistics · Probability theory is a branch of mathematics · Statistics and (statistical) machine learning are attempts to applying probability theory to solving problems in the real function (Gaussian process regression) 3 #12;Dirichlet Processes: Modeling Probability Measures · Dirichlet

Tresp, Volker

126

An energy-diagnostics intercomparison of coupled ice-ocean Arctic models  

E-Print Network [OSTI]

An energy-diagnostics intercomparison of coupled ice-ocean Arctic models Petteri Uotila a,*, David are estimated based on results from six different coupled ice- ocean models. The components of the kinetic of potential and kinetic energies. The models produce arctic boundary undercurrents controlled by the non

Zhang, Jinlun

127

Coupled Model for Heat and Water Transport in a High Level Waste...  

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

algorithm for mineral dehydration is also applied in the modeling. The Finite Element Heat and Mass transfer code (FEHM) is used to simulate coupled thermal, hydrological, and...

128

A Conceptual Approach to Two-Scale Constitutive Modelling For Hydro-Mechanical Coupling  

E-Print Network [OSTI]

Large scale modelling of fluid flow coupled with solid failure in geothermal reservoirs or hydrocarbon extraction from reservoir rocks usually involves behaviours at two scales: lower scale of the inelastic localization zone, and larger scale of the bulk continuum where elastic behaviour can be reasonably assumed. The hydraulic conductivities corresponding to the mechanical properties at these two scales are different. In the bulk elastic host rock, the hydraulic conductivity does not vary much with the deformation, while it significantly changes in the lower scale of the localization zone due to inelastic deformation. Increase of permeability due to fracture and/or dilation, or reduction of permeability due to material compaction can take place inside this zone. The challenge is to predict the evolution of hydraulic conductivities coupled with the mechanical behaviour of the material in all stages of the deformation process. In the early stage of diffuse deformation, the permeability of the material can be reasonably assumed to be homogenous over the whole Representative Volume Element (RVE) However, localized failure results in distinctly different conductivities in different parts of the RVE. This paper establishes a general framework and corresponding field equations to describe the hydro-mechanical coupling in both diffuse and localized stages of deformation in rocks. In particular, embedding the lower scale hydro-mechanical behaviour of the localization zone inside an elastic bulk, together with their corresponding effective sizes, helps effectively deal with scaling issues in large-scale modelling. Preliminary results are presented which demonstrate the promising features of this new approach.

Giang D. Nguyen; Abbas El-Zein; Terry Bennett

2014-06-05T23:59:59.000Z

129

Ocean heat uptake processes: a model intercomparison  

Science Journals Connector (OSTI)

We compare the quasi-equilibrium heat balances, as well as their responses to 4×CO2 perturbation, among three global climate models with the aim to identify and explain inter-model differences in ocean heat uptake (OHU) processes. We find that, in ...

Eleftheria Exarchou; Till Kuhlbrodt; Jonathan M. Gregory; Robin S. Smith

130

Modeling Coupled Surface–Subsurface Flow Processes: A Review  

Science Journals Connector (OSTI)

...MA. Council, G.W. 1999. A lake package for MODFLOW (LAK2): Documentation and users manual, Version 2.2. HSI GeoTrans, Roswell, GA. Crosson, W.L. , C.A. Laymon, R. Inguva, and M. Schamschula. 2002. Assimilating remote sensing...

Alex Furman

131

Forced response of the East Asian summer rainfall over the past millennium: results from a coupled model simulation  

E-Print Network [OSTI]

of a millennium simulation of the coupled ECHO-G model. The model results indicate that the centennial

Wang, Bin

132

Two-stage coal liquefaction process performance with close-coupled reactors  

Science Journals Connector (OSTI)

Close-coupled operation reactors in integrated two-stage liquefaction is an important development in coal liquefaction technology. One such run was completed at the Wilsonville pilot plant using Illinois No. 6 coal. Product yield and product quality data are presented. Comparisons are made with previous data obtained without close-coupling of the reactors. Also, a broad comparison of the performance of a unimodal Shell 324 and a bimodal Amocat 1C catalyst is made. The effect of higher system space velocity on process performance and the impact of solids recycle are discussed. Finally, catalyst replacement rates for “all-distillate” product slate are projected as a function of hydrotreater temperature and system space rate.

Ramakrishna V. Nalitham; Jun M. Lee; Charles W. Lamb; Thomas W. Johnson

1987-01-01T23:59:59.000Z

133

Gas Distribution Modeling using Sparse Gaussian Process Mixture Models  

E-Print Network [OSTI]

Gas Distribution Modeling using Sparse Gaussian Process Mixture Models Cyrill Stachniss1 Christian-- In this paper, we consider the problem of learning a two dimensional spatial model of a gas distribution with a mobile robot. Building maps that can be used to accurately predict the gas concentration at query

Stachniss, Cyrill

134

Improving the assessment of wave energy resources by means of coupled wave-ocean numerical modeling  

Science Journals Connector (OSTI)

Abstract Sea waves energy represents a renewable and sustainable energy resource, that nevertheless needs to be further investigated to make it more cost-effective and economically appealing. A key step in the process of Wave Energy Converters (WEC) deployment is the energy resource assessment at a sea site either measured or obtained through numerical model analysis. In these kind of studies, some approximations are often introduced, especially in the early stages of the process, viz. waves are assumed propagating in deep waters without underneath ocean currents. These aspects are discussed and evaluated in the Adriatic Sea and its northern part (Gulf of Venice) using locally observed and modeled wave data. In particular, to account for a “state of the art” treatment of the Wave–Current Interaction (WCI) we have implemented the Simulating \\{WAves\\} Nearshore (SWAN) model and the Regional Ocean Modeling System (ROMS), fully coupled within the Coupled Ocean Atmosphere Wave Sediment Transport (COAWST) system. COAWST has been applied to a computational grid covering the whole Adriatic Sea and off-line nested to a high-resolution grid in the Gulf of Venice. A 15-year long wave data set collected at the oceanographic tower “Acqua Alta”, located approximately 15 km off the Venice coast, has also been analyzed with the dual purpose of providing a reference to the model estimates and to locally assess the wave energy resource. By using COAWST, we have quantified for the first time to our best knowledge the importance of the WCI effect on wave power estimation. This can vary up to 30% neglecting the current effect. Results also suggest the Gulf of Venice as a suitable testing site for WECs, since it is characterized by periods of calm (optimal for safe installation and maintenance) alternating with severe storms, whose wave energy potentials are comparable to those ordinarily encountered in the energy production sites.

Francesco Barbariol; Alvise Benetazzo; Sandro Carniel; Mauro Sclavo

2013-01-01T23:59:59.000Z

135

Hybrid coupled models of the tropical Paci c |I Interannual variability  

E-Print Network [OSTI]

Hybrid coupled models of the tropical Paci#12;c |I Interannual variability by Youmin Tang 1 University, 251 Mercer Street, New York, NY 10012, USA. Email: ytang@cims.nyu.edu #12; Abstract Two hybrid), hybrid models (e.g., Barnett et al 1993; Balmaseda et al. 1994,1995), and fully coupled general

Hsieh, William

136

Climate Simulations for 1951–2050 with a Coupled Atmosphere–Ocean Model  

Science Journals Connector (OSTI)

The authors simulate climate change for 1951–2050 using the GISS SI2000 atmospheric model coupled to HYCOM, a quasi-isopycnal ocean model (“ocean E”), and contrast the results with those obtained using the same atmosphere coupled to a passive Q-...

Shan Sun; James E. Hansen

2003-09-01T23:59:59.000Z

137

Coupled optical and electrical modeling of solar cell based on conical pore silicon photonic crystals  

E-Print Network [OSTI]

Coupled optical and electrical modeling of solar cell based on conical pore silicon photonic://jap.aip.org/authors #12;Coupled optical and electrical modeling of solar cell based on conical pore silicon photonic, 60 St. George Street, Toronto, Ontario M5S 1A7, Canada (Received 25 March 2013; accepted 27 May 2013

John, Sajeev

138

Coupling GIS and LCA for biodiversity assessments of land use: Part 1: Inventory modeling  

E-Print Network [OSTI]

scenarios were developed with GIS modeling. Current land use0170-9 LAND USE IN LCA Coupling GIS and LCA for biodiversityGeographic information systems (GIS) are adept at modeling

Geyer, Roland; Stoms, David M.; Lindner, Jan P.; Davis, Frank W.; Wittstock, Bastian

2010-01-01T23:59:59.000Z

139

The second Hadley Centre coupled ocean-atmosphere GCM: model description, spinup and validation  

Science Journals Connector (OSTI)

...?This study describes a new coupled ocean-atmosphere general circulation model (OAGCM) developed for studies of climate change and results from a hindcast experiment. The model includes various physical and te...

T. C. Johns; R. E. Carnell; J. F. Crossley; J. M. Gregory…

1997-02-01T23:59:59.000Z

140

Parameter Optimization in an Intermediate Coupled Climate Model with Biased Physics  

Science Journals Connector (OSTI)

Imperfect physical parameterization schemes in a coupled climate model are an important source of model biases that adversely impact climate prediction. However, how observational information should be used to optimize physical parameterizations ...

Xuefeng Zhang; Shaoqing Zhang; Zhengyu Liu; Xinrong Wu; Guijun Han

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141

Attrition and abrasion models for oil shale process modeling  

SciTech Connect (OSTI)

As oil shale is processed, fine particles, much smaller than the original shale are created. This process is called attrition or more accurately abrasion. In this paper, models of abrasion are presented for oil shale being processed in several unit operations. Two of these unit operations, a fluidized bed and a lift pipe are used in the Lawrence Livermore National Laboratory Hot-Recycle-Solid (HRS) process being developed for the above ground processing of oil shale. In two reports, studies were conducted on the attrition of oil shale in unit operations which are used in the HRS process. Carley reported results for attrition in a lift pipe for oil shale which had been pre-processed either by retorting or by retorting then burning. The second paper, by Taylor and Beavers, reported results for a fluidized bed processing of oil shale. Taylor and Beavers studied raw, retorted, and shale which had been retorted and then burned. In this paper, empirical models are derived, from the experimental studies conducted on oil shale for the process occurring in the HRS process. The derived models are presented along with comparisons with experimental results.

Aldis, D.F.

1991-10-25T23:59:59.000Z

142

Exploring chaos to model the design process  

E-Print Network [OSTI]

to a. chaotic svstem mav drive it to neu attractors. Any neiv information introduced to the design proi. ess mav lead to different solutions. CHAPTER II THE FUNDAMENTAL PROCESSES OF DESIGN As ivas stated in the introduction, the first objective... of this researcll v" as i i identify some of the funclamental activities of the design process. In order to acconiphsh tins task. the follniving approach v;as taken. i. 'The hterature ivas surveyed for descriptive models of the design process. klorlcls tliat...

Sharkawy, Ahmed

1990-01-01T23:59:59.000Z

143

Numerical modeling of a thermohydrochemical (T-H-C) coupling and the implications to radionuclide transport.  

SciTech Connect (OSTI)

Thermohydrochemical (T-H-C) processes result from the placement of heat-generating radioactive materials in unsaturated, fractured geologic materials. The placement of materials in the proposed Yucca Mountain repository will result in complex environmental conditions. Simple models are developed liking the thermohydrological effects simulated with TOUGHZ to system chemistry, with an example presented for chloride. Perturbations to near-field chemistry could have a significant impact on the migration of actinides and fission products in geologic materials. Various conceptual models to represent fractures are utilized in TOUGHZ simulations of thermohydrological processes. The simulated moisture redistribution is then coupled to simple chemical models to demonstrate the potential magnitude of T-H-C processes. The concentration of chloride in solution (returning to the engineered barrier system) is demonstrated, in extreme cases, to exceed 100,000 mg/L. The implication is that the system (typically ambient chemical and hydrological conditions) in which radionuclide transport is typically simulated and measured may be significantly different from the perturbed system.

Esh, D. W.; Scheetz, B. E.

1999-09-21T23:59:59.000Z

144

Automatic Verification of Static Policies on Software Process Models  

Science Journals Connector (OSTI)

Software Process Technology evolved to support software processes management by assisting the modeling, enacting and evolution of complex process models. This paper presents a contribution to this field, describing a mechanism to formally model Static ...

Rodrigo Quites Reis; Carla Alessandra Lima Reis; Heribert Schlebbe; Daltro José nunes

2002-12-01T23:59:59.000Z

145

Strongly-coupled Josephson junction array for simulation of frustrated one-dimensional spin models  

E-Print Network [OSTI]

We study the capacitance-coupled Josephson junction array beyond the small-coupling limit. We find that, when the scale of the system is large, its Hamiltonian can be obtained without the small-coupling approximation and the system can be used to simulate strongly frustrated one-dimensional Ising spin problems. To engineer the system Hamiltonian for an ideal theoretical model, we apply a dynamical decoupling technique to eliminate undesirable couplings in the system. Using a 6-site junction array as an example, we numerically evaluate the system to show that it exhibits important characteristics of the frustrated spin model.

Liang-Hui Du; Xingxiang Zhou; Yong-Jian Han; Guang-Can Guo; Zheng-Wei Zhou

2012-12-20T23:59:59.000Z

146

Localized model for systems with double-exchange coupling  

Science Journals Connector (OSTI)

Magnetic spins in crystals of mixed valence can simultaneously experience two kinds of coupling: the superexchange and the double exchange. The latter coupling, first invoked by Zener and further worked out by Anderson and Hasegawa, is mediated by additional electrons or holes introduced into the system. In the present paper an effective site-spins interaction Hamiltonian for double exchange is formulated. This Hamiltonian involves ascending powers of the bilinear interaction S?i·S?j. The highest power is determined by the value of the site spin. Thus, for spin-½ the double exchange interaction looks like the ordinary Heisenberg-type coupling. Spin-1 Hamiltonian contains also a biquadratic coupling. Spin-32 includes a bicubic interaction, spin-2 a biquartic one, etc. It is argued that a localized description of systems with the double exchange is usually sufficient. The phase diagrams are entirely different from the one predicted by the semiclassical (large-spin) band theory proposed by de Gennes. The critical concentrations of the carriers are evaluated at T=0 K in the mean-field-theory approximation. An applied magnetic field is shown to have little influence on the strength of the double-exchange coupling. Spin configurations in the presence of the field are also discussed. Finally, a spin-wave theory for such systems is constructed.

M. Cieplak

1978-10-01T23:59:59.000Z

147

Author's personal copy Two-way coupling of an ENSO model to the global climate model CLIMBER-3a  

E-Print Network [OSTI]

it is possible to introduce ENSO variability to an Earth system Model of Intermediate Complexity (EMIC we are using here. In this study we couple the Earth system model of intermediate complexity (EMIC

Levermann, Anders

148

Performance modeling in the design process  

SciTech Connect (OSTI)

Here, in capsule form, are some lessons learned trying to integrate performance modeling into the design process. Performance modeling should play a central role in system design; ignore it at your peril. The role of performance modeling is not the same in all design projects. Clearly specify performance goals and what factors will affect performance; they try to model those factors. Obtaining the data for the models can be a major problem; ongoing measurement projects are always worthwhile. Prototypes can be valuable data gathering tools if they are instrumented for this purpose. Anticipate the effect of environment on the system you are designing, and the effects of the system on the environment. Including the performance analyst on the design team from the beginning; if he is perceived as an outsider, he is more likely to be ignored, especially if decisions have already been made.

Alexander, W.; Brice, R.

1982-01-01T23:59:59.000Z

149

Do Coupled Climate Models Correctly SImulate the Upward Branch of the Deept Ocean Global Conveyor?  

SciTech Connect (OSTI)

The large-scale meridional overturning circulation (MOC) connects the deep ocean, a major reservoir of carbon, to the other components of the climate system and must therefore be accurately represented in Earth System Models. Our project aims to address the specific question of the pathways and mechanisms controlling the upwelling branch of the MOC, a subject of significant disagreement between models and observational syntheses, and among general circulation models. Observations of these pathways are limited, particularly in regions of complex hydrography such as the Southern Ocean. As such, we rely on models to examine theories of the overturning circulation, both physically and biogeochemically. This grant focused on a particular aspect of the meridional overturning circulation (MOC) where there is currently significant disagreement between models and observationally based analyses of the MOC, and amongst general circulation models. In particular, the research focused on addressing the following questions: 1. Where does the deep water that sinks in the polar regions rise to the surface? 2. What processes are responsible for this rise? 3. Do state-of-the-art coupled GCMs capture these processes? Our research had three key components: observational synthesis, model development and model analysis. In this final report we outline the key results from these areas of research for the 2007 to 2012 grant period. The research described here was carried out primarily by graduate student, Daniele Bianchi (now a Postdoc at McGill University, Canada), and Postdoc Stephanie Downes (now a Research Fellow at The Australian national University, Australia). Additional support was provided for programmers Jennifer Simeon as well as Rick Slater.

Sarmiento, Jorge L; Downes, Stephanie; Bianchi, Daniele

2013-01-17T23:59:59.000Z

150

Fractional Dynamical Model for the Generation of ECG like Signals from Filtered Coupled Van-der Pol Oscillators  

E-Print Network [OSTI]

In this paper, an incommensurate fractional order (FO) model has been proposed to generate ECG like waveforms. Earlier investigation of ECG like waveform generation is based on two identical Van-der Pol (VdP) family of oscillators which are coupled by time delays and gains. In this paper, we suitably modify the three state equations corresponding to the nonlinear cross-product of states, time delay coupling of the two oscillators and low-pass filtering, using the concept of fractional derivatives. Our results show that a wide variety of ECG like waveforms can be simulated from the proposed generalized models, characterizing heart conditions under different physiological conditions. Such generalization of the modelling of ECG waveforms may be useful to understand the physiological process behind ECG signal generation in normal and abnormal heart conditions. Along with the proposed FO models, an optimization based approach is also presented to estimate the VdP oscillator parameters for representing a realistic ...

Das, Saptarshi

2014-01-01T23:59:59.000Z

151

Iron and steel industry process model  

SciTech Connect (OSTI)

The iron and steel industry process model depicts expected energy-consumption characteristics of the iron and steel industry and ancillary industries for the next 25 years by means of a process model of the major steps in steelmaking, from ore mining and scrap recycling to the final finishing of carbon, alloy, and stainless steel into steel products such as structural steel, slabs, plates, tubes, and bars. Two plant types are modeled: fully integrated mills and mini-mills. User-determined inputs into the model are as follows: projected energy and materials prices; projected costs of capacity expansion and replacement; energy-conserving options, both operating modes and investments; the internal rate of return required on investment; and projected demand for finished steel. Nominal input choices in the model for the inputs listed above are as follows: National Academy of Sciences Committee on Nuclear and Alternative Energy Systems Demand Panel nominal energy-price projections for oil, gas, distillates, residuals, and electricity and 1975 actual prices for materials; actual 1975 costs; new technologies added; 15% after taxes; and 1975 actual demand with 1.5%/y growth. The model reproduces the base-year (1975) actual performance of the industry; then, given the above nominal input choices, it projects modes of operation and capacity expansion that minimize the cost of meeting the given final demands for each of 5 years, each year being the midpoint of a 5-year interval. The output of the model includes the following: total energy use and intensity (Btu/ton) by type, by process, and by time period; energy conservation options chosen; utilization rates for existing capacity; capital-investment decisions for capacity expansion.

Sparrow, F.T.; Pilati, D.; Dougherty, T.; McBreen, E.; Juang, L.L.

1980-01-01T23:59:59.000Z

152

Soil remediation using a coupled process: soil washing with surfactant followed by photo-Fenton oxidation  

Science Journals Connector (OSTI)

In the present work the use of a coupled process, soil washing and photo-Fenton oxidation, was investigated for remediation of a soil contaminated with p,p?-DDT (DDT) and p,p?-DDE (DDE), and a soil artificially contaminated with diesel. In the soil washing experiments, Triton X-100 (TX-100) aqueous solutions were used at different concentrations to obtain wastewaters with different compositions. Removal efficiencies of 66% (DDT), 80% (DDE) and 100% (diesel) were achieved for three sequential washings using a TX-100 solution strength equivalent to 12 times the effective critical micelle concentration of the surfactant (12 CMCeff). The wastewater obtained was then treated using a solar photo-Fenton process. After 6 h irradiation, 99, 95 and 100% degradation efficiencies were achieved for DDT, DDE and diesel, respectively. In all experiments, the concentration of dissolved organic carbon decreased by at least 95%, indicating that residual concentration of contaminants and/or TX-100 in the wastewater was very low. The co-extraction of metals was also evaluated. Among the metals analyzed (Pb, Cr, Ni, Cu, Cd, Mn and Co), only Cr and Mn were detected in the wastewater at concentrations above the maximum value permitted by current Brazilian legislation. The effective removal of contaminants from soil by the TX-100 washing process, together with the high degradation efficiency of the solar photo-Fenton process, suggests that this procedure could be a useful option for soil remediation.

Ricardo D. Villa; Alam G. Trovó; Raquel F. Pupo Nogueira

2010-01-01T23:59:59.000Z

153

Comments on the Z electromagnetic couplings in a composite model  

Science Journals Connector (OSTI)

We show how one can generate sizable electromagnetic couplings for the Z (Z??,ZZ?) if the neutral weak boson is a composite particle. Contrary to a recent claim, we show that a superheavy fermionic constituent gives a very suppressed contribution.

F. Boudjema

1987-08-01T23:59:59.000Z

154

A turbulent transport network model in MULTIFLUX coupled with TOUGH2  

SciTech Connect (OSTI)

A new numerical method is described for the fully iterated, conjugate solution of two discrete submodels, involving (a) a transport network model for heat, moisture, and airflows in a high-permeability, air-filled cavity; and (b) a variably saturated fractured porous medium. The transport network submodel is an integrated-parameter, computational fluid dynamics solver, describing the thermal-hydrologic transport processes in the flow channel system of the cavity with laminar or turbulent flow and convective heat and mass transport, using MULTIFLUX. The porous medium submodel, using TOUGH2, is a solver for the heat and mass transport in the fractured rock mass. The new model solution extends the application fields of TOUGH2 by integrating it with turbulent flow and transport in a discrete flow network system. We present demonstrational results for a nuclear waste repository application at Yucca Mountain with the most realistic model assumptions and input parameters including the geometrical layout of the nuclear spent fuel and waste with variable heat load for the individual containers. The MULTIFLUX and TOUGH2 model elements are fully iterated, applying a programmed reprocessing of the Numerical Transport Code Functionalization model-element in an automated Outside Balance Iteration loop. The natural, convective airflow field and the heat and mass transport in a representative emplacement drift during postclosure are explicitly solved in the new model. The results demonstrate that the direction and magnitude of the air circulation patterns and all transport modes are strongly affected by the heat and moisture transport processes in the surrounding rock, justifying the need for a coupled, fully iterated model solution such as the one presented in the paper.

Danko, G.; Bahrami, D.; Birkholzer, J.T.

2011-02-15T23:59:59.000Z

155

Superconducting qubits coupled to nanoelectromechanical resonators: An architecture for solid-state quantum-information processing  

SciTech Connect (OSTI)

We describe the design for a scalable, solid-state quantum-information-processing architecture based on the integration of GHz-frequency nanomechanical resonators with Josephson tunnel junctions, which has the potential for demonstrating a variety of single- and multiqubit operations critical to quantum computation. The computational qubits are eigenstates of large-area, current-biased Josephson junctions, manipulated and measured using strobed external circuitry. Two or more of these phase qubits are capacitively coupled to a high-quality-factor piezoelectric nanoelectromechanical disk resonator, which forms the backbone of our architecture, and which enables coherent coupling of the qubits. The integrated system is analogous to one or more few-level atoms (the Josephson junction qubits) in an electromagnetic cavity (the nanomechanical resonator). However, unlike existing approaches using atoms in electromagnetic cavities, here we can individually tune the level spacing of the 'atoms' and control their 'electromagnetic' interaction strength. We show theoretically that quantum states prepared in a Josephson junction can be passed to the nanomechanical resonator and stored there, and then can be passed back to the original junction or transferred to another with high fidelity. The resonator can also be used to produce maximally entangled Bell states between a pair of Josephson junctions. Many such junction-resonator complexes can be assembled in a hub-and-spoke layout, resulting in a large-scale quantum circuit. Our proposed architecture combines desirable features of both solid-state and cavity quantum electrodynamics approaches, and could make quantum-information processing possible in a scalable, solid-state environment.

Geller, M.R. [Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602-2451 (United States); Cleland, A.N. [Department of Physics, University of California, Santa Barbara, California 93106 (United States)

2005-03-01T23:59:59.000Z

156

Coupling Chemical Transport Model Source Attributions with Positive Matrix Factorization: Application to Two IMPROVE Sites Impacted by Wildfires  

Science Journals Connector (OSTI)

Coupling Chemical Transport Model Source Attributions with Positive Matrix Factorization: Application to Two IMPROVE Sites Impacted by Wildfires ... § Cooperative

Timothy M. Sturtz; Bret A. Schichtel; Timothy V. Larson

2014-09-02T23:59:59.000Z

157

VolumeExplorer: Roaming Large Volumes to Couple Visualization and Data Processing for Oil and Gas Exploration  

E-Print Network [OSTI]

VolumeExplorer: Roaming Large Volumes to Couple Visualization and Data Processing for Oil and Gas dedicated to oil and gas exploration. Our system combines probe- based volume rendering with data processing Seismic interpretation is an important task in the oil and gas exploration-production (EP) workflow [9, 26

Paris-Sud XI, Université de

158

GNEP Coupled End-to-End Demonstration Project Head-End Processing and Tritium Removal Using Voloxidation  

E-Print Network [OSTI]

of operating parameters on removal of volatile fission and activation products. In addition, data fromGNEP Coupled End-to-End Demonstration Project Head-End Processing and Tritium Removal Using fuel per year). The head-end processing segment includes single-pin shearing, voloxidation to remove

Pennycook, Steve

159

Use of Coupled Rate Equations To Describe Nucleation-and-Branching Rate-Limited Solid-State Processes  

Science Journals Connector (OSTI)

Use of Coupled Rate Equations To Describe Nucleation-and-Branching Rate-Limited Solid-State Processes ... Coincident with nuclei growth may be the process of nuclei multiplication or “branching”. ... We consider that nucleation and branching may be considered as two interrelated yet distinct steps (often rate determining) in a series of steps required to achieve a conversion. ...

Peter J. Skrdla

2004-07-20T23:59:59.000Z

160

From Children's Perspectives: A Model of Aesthetic Processing in Theatre  

E-Print Network [OSTI]

A model of aesthetic processing describes how child audiences create meanings of plays in performances.

Klein, Jeanne

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

Design of Nanostructured Solar Cells Using Coupled Optical and Electrical Modeling  

E-Print Network [OSTI]

Design of Nanostructured Solar Cells Using Coupled Optical and Electrical Modeling Michael G of Applied Physics, California Institute of Technology, Pasadena, California 91125, United States Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States

Atwater, Harry

162

ENSO Bred Vectors in Coupled Ocean–Atmosphere General Circulation Models  

Science Journals Connector (OSTI)

The breeding method has been implemented in the NASA Seasonal-to-Interannual Prediction Project (NSIPP) coupled general circulation model (CGCM) with the ultimate goal of improving operational seasonal to interannual climate predictions through ...

S-C. Yang; E. Kalnay; M. Cai; M. Rienecker; G. Yuan; Z. Toth

2006-04-01T23:59:59.000Z

163

Lee H. MacDonald often coupled with modeling-is essential  

E-Print Network [OSTI]

Lee H. MacDonald often coupled with modeling- is essential to determine the most cost-effective ap outlined in MacDonald, Smart, and Wissmar (13), while suggesting some additional points and refinements

MacDonald, Lee

164

The New Hadley Centre Climate Model (HadGEM1): Evaluation of Coupled Simulations  

Science Journals Connector (OSTI)

A new coupled general circulation climate model developed at the Met Office's Hadley Centre is presented, and aspects of its performance in climate simulations run for the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC ...

T. C. Johns; C. F. Durman; H. T. Banks; M. J. Roberts; A. J. McLaren; J. K. Ridley; C. A. Senior; K. D. Williams; A. Jones; G. J. Rickard; S. Cusack; W. J. Ingram; M. Crucifix; D. M. H. Sexton; M. M. Joshi; B.-W. Dong; H. Spencer; R. S. R. Hill; J. M. Gregory; A. B. Keen; A. K. Pardaens; J. A. Lowe; A. Bodas-Salcedo; S. Stark; Y. Searl

2006-04-01T23:59:59.000Z

165

The Coupling between Wind and Waves in the WAM Model  

Science Journals Connector (OSTI)

The reliability of the wave model (WAM, cycle 4) for predicting waves and wind stress in restricted fetches is investigated using measured data obtained during the Risø Air–Sea Experiment (RASEX) at Vindeby, Denmark. The WAM model includes ...

H. K. Johnson; H. J. Vested; Hans Hersbach; J. Højstrup; S. E. Larsen

1999-11-01T23:59:59.000Z

166

Multiphase Flow Modeling of Biofuel Production Processes  

SciTech Connect (OSTI)

As part of the Idaho National Laboratory's (INL's) Secure Energy Initiative, the INL is performing research in areas that are vital to ensuring clean, secure energy supplies for the future. The INL Hybrid Energy Systems Testing (HYTEST) Laboratory is being established to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. HYTEST involves producing liquid fuels in a Hybrid Energy System (HES) by integrating carbon-based (i.e., bio-mass, oil-shale, etc.) with non-carbon based energy sources (i.e., wind energy, hydro, geothermal, nuclear, etc.). Advances in process development, control and modeling are the unifying vision for HES. This paper describes new modeling tools and methodologies to simulate advanced energy processes. Needs are emerging that require advanced computational modeling of multiphase reacting systems in the energy arena, driven by the 2007 Energy Independence and Security Act, which requires production of 36 billion gal/yr of biofuels by 2022, with 21 billion gal of this as advanced biofuels. Advanced biofuels derived from microalgal biomass have the potential to help achieve the 21 billion gal mandate, as well as reduce greenhouse gas emissions. Production of biofuels from microalgae is receiving considerable interest due to their potentially high oil yields (around 600 gal/acre). Microalgae have a high lipid content (up to 50%) and grow 10 to 100 times faster than terrestrial plants. The use of environmentally friendly alternatives to solvents and reagents commonly employed in reaction and phase separation processes is being explored. This is accomplished through the use of hydrothermal technologies, which are chemical and physical transformations in high-temperature (200-600 C), high-pressure (5-40 MPa) liquid or supercritical water. Figure 1 shows a simplified diagram of the production of biofuels from algae. Hydrothermal processing has significant advantages over other biomass processing methods with respect to separations. These 'green' alternatives employ a hybrid medium that, when operated supercritically, offers the prospect of tunable physicochemical properties. Solubility can be rapidly altered and phases partitioned selectively to precipitate or dissolve certain components by altering temperature or pressure in the near-critical region. The ability to tune the solvation properties of water in the highly compressible near-critical region facilitates partitioning of products or by-products into separate phases to separate and purify products. Since most challenges related to lipid extraction are associated with the industrial scale-up of integrated extraction systems, the new modeling capability offers the prospect of addressing previously untenable scaling issues.

D. Gaston; D. P. Guillen; J. Tester

2011-06-01T23:59:59.000Z

167

Three-dimensional model for fusion processes  

SciTech Connect (OSTI)

Active galactic nuclei (AGN) emit unusual spectra of radiation which is interpreted to signify extreme distance, extreme power, or both. The status of AGNs was recently reviewed by Balick and Heckman. It seems that the greatest conceptual difficulty with understanding AGNs is how to form a coherent phenomenological model of their properties. What drives the galactic engine. What and where are the mass-flows of fuel to this engine. Are there more than one engine. Do the engines have any symmetry properties. Is observed radiation isotropically emitted from the source. If it is polarized, what causes the polarization. Why is there a roughly spherical cloud of ionized gas about the center of our own galaxy, the Milky Way. The purpose of this paper is to discuss a new model, based on fusion processes which are not axisymmetric, uniform, isotropic, or even time-invariant. Then, the relationship to these questions will be developed. A unified model of fusion processes applicable to many astronomical phenomena will be proposed and discussed.

Olson, A.P.

1984-01-01T23:59:59.000Z

168

Validation of the coupled Eta/SSiB model over South America Sin Chan Chou  

E-Print Network [OSTI]

Validation of the coupled Eta/SSiB model over South America Sin Chan Chou Centro de Previsa~o de with the Simplified Simple Biosphere model (SSiB) over South America. The goal of the present work is to validate of the precipitation annual cycle observed in the central part of South America. The model was integrated continuously

Xue, Yongkang

169

Numerical Modeling of Nonlinear Coupling between Lines/Beams with Multiple Floating Bodies  

E-Print Network [OSTI]

spring model and the three(3) dimensional FE beam model. The coupling of the TLP motion with the reaction force at the tie-down clamp is considered by using exact nonlinear dynamic equations of the motion with the reaction forces modeled with the spring...

Yang, Chan K.

2010-07-14T23:59:59.000Z

170

Ice-ocean boundary conditions for coupled models Gavin A. Schmidt  

E-Print Network [OSTI]

that must be simulated in any comprehensive earth system model incorporating ocean, atmosphere, sea ice different groups (a central fo- cus in the ongoing PRogramme for Integrated earth System Modelling (PRISM) and Earth System Modeling Framework (ESMF) projects). This paper addresses developments in coupling at sea

Bitz, Cecilia

171

The Carbon-Land Model Intercomparison Project (C-LAMP): A Model-Data Comparison System for Evaluation of Coupled Biosphere-Atmosphere Models  

SciTech Connect (OSTI)

The need to capture important climate feebacks in general circulation models (GCMs) has resulted in new efforts to include atmospheric chemistry and land and ocean biogeochemistry into the next generation of production climate models, now often referred to as Earth System Models (ESMs). While many terrestrial and ocean carbon models have been coupled to GCMs, recent work has shown that such models can yield a wide range of results, suggesting that a more rigorous set of offline and partially coupled experiments, along with detailed analyses of processes and comparisons with measurements, are warranted. The Carbon-Land Model Intercomparison Project (C-LAMP) provides a simulation protocol and model performance metrics based upon comparisons against best-available satellite- and ground-based measurements (Hoffman et al., 2007). C-LAMP provides feedback to the modeling community regarding model improvements and to the measurement community by suggesting new observational campaigns. C-LAMP Experiment 1 consists of a set of uncoupled simulations of terrestrial carbon models specifically designed to examine the ability of the models to reproduce surface carbon and energy fluxes at multiple sites and to exhibit the influence of climate variability, prescribed atmospheric carbon dioxide (CO{sub 2}), nitrogen (N) deposition, and land cover change on projections of terrestrial carbon fluxes during the 20th century. Experiment 2 consists of partially coupled simulations of the terrestrial carbon model with an active atmosphere model exchanging energy and moisture fluxes. In all experiments, atmospheric CO{sub 2} follows the prescribed historical trajectory from C{sup 4}MIP. In Experiment 2, the atmosphere model is forced with prescribed sea surface temperatures (SSTs) and corresponding sea ice concentrations from the Hadley Centre; prescribed CO{sub 2} is radiatively active; and land, fossil fuel, and ocean CO{sub 2} fluxes are advected by the model. Both sets of experiments have been performed using two different terrestrial biogeochemistry modules coupled to the Community Land Model version 3 (CLM3) in the Community Climate System Model version 3 (CCSM3): The CASA model of Fung, et al., and the carbon-nitrogen (CN) model of Thornton. Comparisons against Ameriflus site measurements, MODIS satellite observations, NOAA flask records, TRANSCOM inversions, and Free Air CO{sub 2} Enrichment (FACE) site measurements, and other datasets have been performed and are described in Randerson et al. (2009). The C-LAMP diagnostics package was used to validate improvements to CASA and CN for use in the next generation model, CLM4. It is hoped that this effort will serve as a prototype for an international carbon-cycle model benchmarking activity for models being used for the Inter-governmental Panel on Climate Change (IPCC) Fifth Assessment Report. More information about C-LAMP, the experimental protocol, performance metrics, output standards, and model-data comparisons from the CLM3-CASA and CLM3-CN models are available at http://www.climatemodeling.org/c-lamp.

Hoffman, Forrest M [ORNL; Randerson, Jim [University of California, Irvine; Thornton, Peter E [ORNL; Mahowald, Natalie [Cornell University; Bonan, Gordon [National Center for Atmospheric Research (NCAR); Running, Steven [University of Montana, Missoula; Fung, Inez [University of California, Berkeley

2009-01-01T23:59:59.000Z

172

Coupled two-dimensional edge plasma and neutral gas modeling of tokamak scrape-off-layers  

SciTech Connect (OSTI)

The objective of this study is to devise a detailed description of the tokamak scrape-off-layer (SOL), which includes the best available models of both the plasma and neutral species and the strong coupling between the two in many SOL regimes. A good estimate of both particle flux and heat flux profiles at the limiter/divertor target plates is desired. Peak heat flux is one of the limiting factors in determining the survival probability of plasma-facing-components at high power levels. Plate particle flux affects the neutral flux to the pump, which determines the particle exhaust rate. A technique which couples a two-dimensional (2-D) plasma and a 2-D neutral transport code has been developed (coupled code technique), but this procedure requires large amounts of computer time. Relevant physics has been added to an existing two-neutral-species model which takes the SOL plasma/neutral coupling into account in a simple manner (molecular physics model), and this model is compared with the coupled code technique mentioned above. The molecular physics model is benchmarked against experimental data from a divertor tokamak (DIII-D), and a similar model (single-species model) is benchmarked against data from a pump-limiter tokamak (Tore Supra). The models are then used to examine two key issues: free-streaming-limits (ion energy conduction and momentum flux) and the effects of the non-orthogonal geometry of magnetic flux surfaces and target plates on edge plasma parameter profiles.

Maingi, R. [North Carolina State Univ., Raleigh, NC (United States)

1992-08-01T23:59:59.000Z

173

Coupled Thermal-Hydrological-Mechanical-Chemical Model And Experiments...  

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

of mechanistic crack growth and grain contact models for chemically induced subcritical crack growth and pressure solution, with porosity-permeability changes * Conduct...

174

Coupled Thermal-Hydrological-Mechanical-Chemical Model and Experiments...  

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

of mechanistic crack growth and grain contact models for chemically induced subcritical crack growth and pressure solution, with porosity-permeability changes * Conduct...

175

Status and Improvements of Coupled General Circulation Models  

Science Journals Connector (OSTI)

...change impacts; and (iv) be a firmer basis for Earth system models that describe the feedbacks of societies to climate...change impacts; and (iv) be a firmer basis for Earth system models that describe the feedbacks of societies to climate...

Hartmut Grassl

2000-06-16T23:59:59.000Z

176

Toward self-describing and workflow integrated Earth system models: A coupled atmosphere-ocean modeling system application  

Science Journals Connector (OSTI)

The complexity of Earth system models and their applications is increasing as a consequence of scientific advances, user demand, and the ongoing development of computing platforms, storage systems and distributed high-resolution observation networks. ... Keywords: Coupled Earth system models, Provenance information, ROMS, Scientific workflow, Self-describing models, WRF

Ufuk Utku Turuncoglu; Nuzhet Dalfes; Sylvia Murphy; Cecelia Deluca

2013-01-01T23:59:59.000Z

177

Coupling the Mixed Potential and Radiolysis Models for Used Fuel Degradation  

SciTech Connect (OSTI)

The primary purpose of this report is to describe the strategy for coupling three process level models to produce an integrated Used Fuel Degradation Model (FDM). The FDM, which is based on fundamental chemical and physical principals, provides direct calculation of radionuclide source terms for use in repository performance assessments. The G-value for H2O2 production (Gcond) to be used in the Mixed Potential Model (MPM) (H2O2 is the only radiolytic product presently included but others will be added as appropriate) needs to account for intermediate spur reactions. The effects of these intermediate reactions on [H2O2] are accounted for in the Radiolysis Model (RM). This report details methods for applying RM calculations that encompass the effects of these fast interactions on [H2O2] as the solution composition evolves during successive MPM iterations and then represent the steady-state [H2O2] in terms of an “effective instantaneous or conditional” generation value (Gcond). It is anticipated that the value of Gcond will change slowly as the reaction progresses through several iterations of the MPM as changes in the nature of fuel surface occur. The Gcond values will be calculated with the RM either after several iterations or when concentrations of key reactants reach threshold values determined from previous sensitivity runs. Sensitivity runs with RM indicate significant changes in G-value can occur over narrow composition ranges. The objective of the mixed potential model (MPM) is to calculate the used fuel degradation rates for a wide range of disposal environments to provide the source term radionuclide release rates for generic repository concepts. The fuel degradation rate is calculated for chemical and oxidative dissolution mechanisms using mixed potential theory to account for all relevant redox reactions at the fuel surface, including those involving oxidants produced by solution radiolysis and provided by the radiolysis model (RM). The RM calculates the concentration of species generated at any specific time and location from the surface of the fuel. Several options being considered for coupling the RM and MPM are described in the report. Different options have advantages and disadvantages based on the extent of coding that would be required and the ease of use of the final product.

Buck, Edgar C.; Jerden, James L.; Ebert, William L.; Wittman, Richard S.

2013-08-30T23:59:59.000Z

178

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

179

TSPA Model Development and Sensitivity Analysis of Processes...  

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

of Processes Affecting Performance of a Salt Repository for Disposal of Heat-Generating Nuclear Waste TSPA Model Development and Sensitivity Analysis of Processes Affecting...

180

Modeling of HCCI and PCCI Combustion Processes | Department of...  

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

HCCI and PCCI Combustion Processes Modeling of HCCI and PCCI Combustion Processes 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters...

Note: This page contains sample records for the topic "modeling coupled processes" 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

Density-fitted singles and doubles coupled cluster on graphics processing units  

SciTech Connect (OSTI)

We adapt an algorithm for singles and doubles coupled cluster (CCSD) that uses density fitting (DF) or Cholesky decomposition (CD) in the construction and contraction of all electron repulsion integrals (ERI s) for use on heterogeneous compute nodes consisting of a multicore CPU and at least one graphics processing unit (GPU). The use of approximate 3-index ERI s ameliorates two of the major difficulties in designing scientific algorithms for GPU s: (i) the extremely limited global memory on the devices and (ii) the overhead associated with data motion across the PCI bus. For the benzene trimer described by an aug-cc-pVDZ basis set, the use of a single NVIDIA Tesla C2070 (Fermi) GPU accelerates a CD-CCSD computation by a factor of 2.1, relative to the multicore CPU-only algorithm that uses 6 highly efficient Intel core i7-3930K CPU cores. The use of two Fermis provides an acceleration of 2.89, which is comparable to that observed when using a single NVIDIA Kepler K20c GPU (2.73).

Sherrill, David [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta; Sumpter, Bobby G [ORNL] [ORNL; DePrince, III, A. Eugene [Georgia Institute of Technology, Atlanta

2014-01-01T23:59:59.000Z

182

The dissipated energy of electrode surfaces: Temperature jumps from coupled transport processes  

SciTech Connect (OSTI)

Nonequilibrium thermodynamics for surfaces has been applied to the electrode surfaces of an electrochemical cell. It is shown that the temperature of the surface differs from that of the adjacent electrolyte and electrode, and that a temperature jump exists across the surface. mathematical expressions are derived for the temperature profiles of two cells at steady-state conditions. Methods for estimating transport coefficients for the coupled transport processes at the electrode surface are discussed. Possible numerical results for the temperature profile, the overpotential, and the dissipated energy are reported. The results reflect the relative importance of heat conductivities, electric conductivities, and the Peltier coefficients for the electrode surface phenomena in combination with bulk properties. Significant temperature jumps may occur at normal electrolysis conditions 10{sup 3} to 10{sup 4} A/m, and for temperature jump coefficients which are smaller than 10{sup 3} J/s K{sup 2} m{sup 2}. The overpotential may have contributions from the Peltier coefficients for the surface larger than the ohmic contribution. The method of analysis gives new information useful for heat control of electrochemical cells, electrode kinetic studies, and interpretation of overpotentials.

Bedeaux, D. [Univ. of Leiden (Netherlands). Dept. of Physical and Macromolecular Chemistry; Ratkje, S.K. [Univ. of Trondheim (Norway)

1996-03-01T23:59:59.000Z

183

E-Print Network 3.0 - advanced processes coupled Sample Search...  

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

Collection: Physics 6 SENSITIVITY ANALYSIS AND APPLICATION GUIDES FOR INTEGRATED BUILDING ENERGY AND CFD SIMULATION Summary: coupling strategy. For instance, a one-step or two-step...

184

System Size Resonance in Coupled Noisy Systems and in the Ising Model  

Science Journals Connector (OSTI)

We consider an ensemble of coupled nonlinear noisy oscillators demonstrating in the thermodynamic limit an Ising-type transition. In the ordered phase and for finite ensembles stochastic flips of the mean field are observed with the rate depending on the ensemble size. When a small periodic force acts on the ensemble, the linear response of the system has a maximum at a certain system size, similar to the stochastic resonance phenomenon. We demonstrate this effect of system size resonance for different types of noisy oscillators and for different ensembles—lattices with nearest neighbors coupling and globally coupled populations. The Ising model is also shown to demonstrate the system size resonance.

A. Pikovsky; A. Zaikin; M. A. de la Casa

2002-01-16T23:59:59.000Z

185

Instrumental vetoes for transient gravitational-wave triggers using noise-coupling models: The bilinear-coupling veto  

E-Print Network [OSTI]

LIGO and Virgo recently completed searches for gravitational waves at their initial target sensitivities, and soon Advanced LIGO and Advanced Virgo will commence observations with even better capabilities. In the search for short duration signals, such as coalescing compact binary inspirals or "burst" events, noise transients can be problematic. Interferometric gravitational-wave detectors are highly complex instruments, and, based on the experience from the past, the data often contain a large number of noise transients that are not easily distinguishable from possible gravitational-wave signals. In order to perform a sensitive search for short-duration gravitational-wave signals it is important to identify these noise artifacts, and to "veto" them. Here we describe such a veto, the bilinear-coupling veto, that makes use of an empirical model of the coupling of instrumental noise to the output strain channel of the interferometric gravitational-wave detector. In this method, we check whether the data from the output strain channel at the time of an apparent signal is consistent with the data from a bilinear combination of auxiliary channels. We discuss the results of the application of this veto on recent LIGO data, and its possible utility when used with data from Advanced LIGO and Advanced Virgo.

Parameswaran Ajith; Tomoki Isogai; Nelson Christensen; Rana Adhikari; Aaron B. Pearlman; Alex Wein; Alan J. Weinstein; Ben Yuan

2014-05-27T23:59:59.000Z

186

Coupled axisymmetric finite element model of a hydraulically amplified magnetostrictive actuator for active powertrain mounts  

Science Journals Connector (OSTI)

A coupled axisymmetric finite element model is formulated to describe the dynamic performance of a hydraulically amplified magnetostrictive actuator for active powertrain mounts. The formulation is based on the weak form representations of Maxwell's ... Keywords: Active powertrain mount, Actuator, Axisymmetric model, Magnetostriction, Terfenol-D

Suryarghya Chakrabarti; Marcelo J. Dapino

2012-11-01T23:59:59.000Z

187

INTERROOM RADIATIVE COUPLINGS THROUGH WINDOWS AND LARGE OPENINGS IN BUILDINGS : PROPOSAL OF A SIMPLIFIED MODEL  

E-Print Network [OSTI]

INTERROOM RADIATIVE COUPLINGS THROUGH WINDOWS AND LARGE OPENINGS IN BUILDINGS : PROPOSAL OF A SIMPLIFIED MODEL H. Boyer1 , M. Bojic2 , H. Ennamiri1 , D. Calogine1 , S. Guichard1 1 University of La Corresponding author : harry.boyer@univ-reunion.fr ABSTRACT A simplified model of indoor short wave radiation

Paris-Sud XI, Université de

188

Magnetic moment of hyperons in nuclear matter by using quark-meson coupling models  

E-Print Network [OSTI]

We calculate the magnetic moments of hyperons in dense nuclear matter by using relativistic quark models. Hyperons are treated as MIT bags, and the interactions are considered to be mediated by the exchange of scalar and vector mesons which are approximated as mean fields. Model dependence is investigated by using the quark-meson coupling model and the modified quark-meson coupling model; in the former the bag constant is independent of density and in the latter it depends on density. Both models give us the magnitudes of the magnetic moments increasing with density for most octet baryons. But there is a considerable model dependence in the values of the magnetic moments in dense medium. The magnetic moments at the nuclear saturation density calculated by the quark meson coupling model are only a few percents larger than those in free space, but the magnetic moments from the modified quark meson coupling model increase more than 10% for most hyperons. The correlations between the bag radius of hyperons and the magnetic moments of hyperons in dense matter are discussed.

C. Y. Ryu; C. H. Hyun; T. -S. Park; S. W. Hong

2008-06-06T23:59:59.000Z

189

STOCHASTIC COMPUTATIONAL DYNAMICAL MODEL OF UNCERTAIN STRUCTURE COUPLED WITH AN INSULATION LAYER  

E-Print Network [OSTI]

STOCHASTIC COMPUTATIONAL DYNAMICAL MODEL OF UNCERTAIN STRUCTURE COUPLED WITH AN INSULATION LAYER the effect of insulation layers in complex dynamical systems for low- and medium-frequency ranges such as car booming noise analysis, one introduces a sim- plified stochastic model of insulation layers based

Boyer, Edmond

190

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.

191

Constraining Transient Climate Sensitivity Using Coupled Climate Model Simulations of Volcanic Eruptions  

Science Journals Connector (OSTI)

Coupled climate model simulations of volcanic eruptions and abrupt changes in CO2 concentration are compared in multiple realizations of the Geophysical Fluid Dynamics Laboratory Climate Model, version 2.1 (GFDL CM2.1). The change in global-mean ...

Timothy M. Merlis; Isaac M. Held; Georgiy L. Stenchikov; Fanrong Zeng; Larry W. Horowitz

2014-10-01T23:59:59.000Z

192

Testing a Coupled Ice-Mixed-Layer Model Under Subarctic Conditions  

Science Journals Connector (OSTI)

A one-dimensional oceanic mixed-layer model has been coupled with a thermodynamic sea ice model in order to study the seasonal cycle of ice-ocean interaction in the subarctic ocean. The ice thickness is assumed constant and only variations of ice ...

Marie-Noëlle Houssais

1988-02-01T23:59:59.000Z

193

Numerical Early Warning Model Research of Landfill Gas Permeation and Diffusion Considering Flow-Temperature Coupling  

Science Journals Connector (OSTI)

Based on seepage mechanics in porous medium gas and heat transfer theory, numerical early warning model is established, which is on quantitative description of migration and release of landfill gas and penetration and diffusion of energy, and dynamic ... Keywords: component, landfill gas, flow-temperature coupling, gas pressure and temperature distribution, numerical early warning model

Xue Qiang; Feng Xia-ting; Ma Shi-jin; Zhou Xiao-jun

2009-10-01T23:59:59.000Z

194

Block Preconditioning for a Coupled Model of Transport with Sorption in Porous Media  

E-Print Network [OSTI]

Block Preconditioning for a Coupled Model of Transport with Sorption in Porous Media List consider a simplified model with one species undergoing a sorption reaction, given by a known equilibrium and D is the diffusion­ dispersion tensor. The sorption isotherm in equation (1) will be taken

Boyer, Edmond

195

Addressing model error through atmospheric stochastic physical parametrizations: impact on the coupled ECMWF seasonal forecasting system  

Science Journals Connector (OSTI)

...parametrizations: impact on the coupled ECMWF...Stochastic modelling and energy-efficient computing...effects of sub-grid-scale variability...present results of the impact of these schemes...and near-surface winds. Positive impact...Stochastic modelling and energy-efficient computing...

2014-01-01T23:59:59.000Z

196

MODELING COUPLED FLUID FLOW AND GEOMECHANICAL AND GEOPHYSICAL PHENOMENA WITHIN  

E-Print Network [OSTI]

porosity (range: 5% to 45%) and reservoir permeability (range: 1e-11 m2 to 1e-14 m2 ). Lower reservoir pressure profiles throughout the reservoir during constant production. As the initial reservoir porosity for the modeling of geomechanical effects induced by reservoir production/injection and the cyclic dependence

197

Coupling structural and functional models for interaction design  

Science Journals Connector (OSTI)

......map. Structural models, such as the subway map in this example, describe the internal...instance, returning to the example of the subway passenger given above, the passenger's...word processor, a cellular phone, a car audio system, and an ultrasonic device. The......

Dong-Seok Lee; Wan Chul Yoon

2004-02-01T23:59:59.000Z

198

Coupled thermodynamic-dynamic semi-analytical model of Free Piston Stirling engines  

E-Print Network [OSTI]

The study of free piston Stirling engine (FPSE) requires both accurate thermodynamic and dynamic modelling to predict its performances. The steady state behaviour of the engine partly relies on non linear dissipative phenomena such as pressure drop loss within heat exchangers which is dependant on the temperature within the associated components. An analytical thermodynamic model which encompasses the effectiveness and the flaws of the heat exchangers and the regenerator has been previously developed and validated. A semi-analytical dynamic model of FPSE is developed and presented in this paper. The thermodynamic model is used to define the thermal variables that are used in the dynamic model which evaluates the kinematic results. Thus, a coupled iterative strategy has been used to perform a global simulation. The global modelling approach has been validated using the experimental data available from the NASA RE-1000 Stirling engine prototype. The resulting coupled thermodynamic-dynamic model using a standard...

Formosa, Fabien

2013-01-01T23:59:59.000Z

199

Paper Number -1-Simulation model of dispersions in turning process  

E-Print Network [OSTI]

Paper Number -1- Simulation model of dispersions in turning process Wolff Valery 1, Lefebvre Arnaud. In this paper, an extent of the simulation model of dispersions in turning process first exposed in [W1

Paris-Sud XI, Université de

200

Representing Cloud Processing of Aerosol in Numerical Models  

SciTech Connect (OSTI)

The satellite imagery in Figure 1 provides dramatic examples of how aerosol influences the cloud field. Aerosol from ship exhaust can serve as nucleation centers in otherwise cloud-free regions, forming ship tracks (top image), or can enhance the reflectance/albedo in already cloudy regions. This image is a demonstration of the first indirect effect, in which changes in aerosol modulate cloud droplet radius and concentration, which influences albedo. It is thought that, through the effects it has on precipitation (drizzle), aerosol can also affect the structure and persistence of planetary boundary layer (PBL) clouds. Regions of cellular convection, or open pockets of cloudiness (bottom image) are thought to be remnants of strongly drizzling PBL clouds. Pockets of Open Cloudiness (POCs) (Stevens et al. 2005) or Albrecht's ''rifts'' are low cloud fraction regions characterized by anomalously low aerosol concentrations, implying they result from precipitation. These features may in fact be a demonstration of the second indirect effect. To accurately represent these clouds in numerical models, we have to treat the coupled cloud-aerosol system. We present the following series of mesoscale and large eddy simulation (LES) experiments to evaluate the important aspects of treating the coupled cloud-aerosol problem. 1. Drizzling and nondrizzling simulations demonstrate the effect of drizzle on a mesoscale forecast off the California coast. 2. LES experiments with explicit (bin) microphysics gauge the relative importance of the shape of the aerosol spectrum on the 3D dynamics and cloud structure. 3. Idealized mesoscale model simulations evaluate the relative roles of various processes, sources, and sinks.

Mechem, D.B.; Kogan, Y.L.

2005-03-18T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

Using Coupled Harmonic Oscillators to Model Some Greenhouse Gas Molecules  

SciTech Connect (OSTI)

Common greenhouse gas molecules SF{sub 6}, NO{sub 2}, CH{sub 4}, and CO{sub 2} are modeled as harmonic oscillators whose potential and kinetic energies are derived. Using the Euler-Lagrange equation, their equations of motion are derived and their phase portraits are plotted. The authors use these data to attempt to explain the lifespan of these gases in the atmosphere.

Go, Clark Kendrick C.; Maquiling, Joel T. [Department of Physics, Ateneo de Manila University, Katipunan Avenue, Quezon City (Philippines)

2010-07-28T23:59:59.000Z

202

Modeling Faults to Improve Election Process Robustness  

E-Print Network [OSTI]

this approach for the Yolo County election process. We focuson the election process used by Yolo County, California 2 .cally on the part of the Yolo County process that deals with

2010-01-01T23:59:59.000Z

203

NREL Biorefinery Analysis Process Models | Open Energy Information  

Open Energy Info (EERE)

NREL Biorefinery Analysis Process Models AgencyCompany Organization: National Renewable Energy Laboratory Website: www.nrel.govextranetbiorefineryaspenmodels Transport...

204

Online Modeling in the Process Industry for Energy Optimization  

E-Print Network [OSTI]

"This paper discusses how steady state models are being used in the process industry to perform online energy optimization of steam and electrical systems. It presents process demands commonly found in the processing industry in terms of steam...

Alexander, J.

205

APPLYING ACTIVITY PATTERNS FOR DEVELOPING AN INTELLIGENT PROCESS MODELING TOOL  

E-Print Network [OSTI]

attracting the interest of both BPM researchers and BPM tool vendors. Frequently, process models can Process Management (BPM) tools as well as emerging patterns for process modeling and change. BPM processes of an enterprise. Moreover, through Web service technology, the benefits of BPM can be created

Ulm, Universität

206

Engineering Process Coordination based on A Service Event Notification Model  

E-Print Network [OSTI]

Engineering Process Coordination based on A Service Event Notification Model Jian Cao1, Jie Wang2 the project lifecycle process. Grid-based engineering service is a potentially useful technology for process coordination. Thus we propose a Grid service based event notification model to support engineering process

Stanford University

207

Spatial Data Models and Query Processing Hanan Samet  

E-Print Network [OSTI]

Spatial Data Models and Query Processing Hanan Samet Walid G. Aref Computer Science Department databases. The focus is on data models and query processing. Query optimization in a spatial environment is also brie y discussed. Keywords and phrases: spatial databases, data models, spatial query processing

Samet, Hanan

208

Non-linear curvature perturbation in multi-field inflation models with non-minimal coupling  

SciTech Connect (OSTI)

Using the ?N formalism we consider the non-linear curvature perturbation in multi-field models of inflation with non-minimal coupling. In particular, we focus on the relation between the ?N formalism as applied in the conformally related Jordan and Einstein frames. Exploiting results already known in the Einstein frame, we give expressions for the power spectrum, spectral tilt and non-gaussianity associated with the Jordan frame curvature perturbation. In the case that an adiabatic limit has not been reached, we find that in general these quantities differ from those associated with the Einstein frame curvature perturbation, and also confirm their equivalence in the absence of isocurvature modes. We then proceed to consider two analytically soluble examples, the first involving a non-minimally coupled 'spectator' field and the second being a non-minimally coupled extension of the multi-brid inflation model. In the first model we find that predictions can easily be brought into agreement with the recent Planck results, as the tensor-to-scalar ratio is generally small, the spectral tilt tuneable and the non-gaussianity suppressed. In the second model we find that predictions for all three parameters can differ substantially from those predicted in the minimally coupled case, and that the recent Planck results for the spectral tilt can be used to constrain the non-minimal coupling parameters.

White, Jonathan; Minamitsuji, Masato; Sasaki, Misao, E-mail: jwhite@yukawa.kyoto-u.ac.jp, E-mail: masato.minamitsuji@ist.utl.pt, E-mail: misao@yukawa.kyoto-u.ac.jp [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)

2013-09-01T23:59:59.000Z

209

The Decision-Making Process of Genetically At-Risk Couples Considering Preimplantation Genetic Diagnosis: Initial Findings from a Grounded Theory Study  

E-Print Network [OSTI]

Decision Making; Decision Theory; Family Planning; In VitroDecision-Making Process of Genetically At-Risk Couples Considering Preimplantation Genetic Diagnosis: Initial Findings from a Grounded Theory

Hershberger, Patricia E.; Gallo, Agatha M.; Kavanaugh, Karen; Olshansky, Ellen; Schwartz, Alan; Tur-Kaspa, Ilan

2012-01-01T23:59:59.000Z

210

Soldering with solid state and diode lasers: Energy coupling, temperature rise, process window  

Science Journals Connector (OSTI)

The increasing number of electrical contacts in automobiles in combination with more complex and miniaturized components leads to higher requirements for the joining technologies. In that context laser soldering represents an interesting alternative to conventional techniques. So far solid state lasers[Nd:yttrium–aluminum–garnet(YAG)] and CO 2 lasers have been successfully applied in industrial production. Recently the development of high power diode lasers has offered a new laser source for soldering with technological advantages. Absorptivity of laser radiation on metals generally increases with shorter wavelength and consequently diode lasers may lead to a higher process efficiency compared to Nd:YAG lasers. The absorptivity of copper alloys with different surface conditions has been measured at 808 nm (diode) and 1064 nm (Nd:YAG). When heating up the solder joint the intensity distribution of the different laser spots becomes important too. This effect is demonstrated by means of process modeling and temperature measurements for a typical joint geometry. For the case of soldering strip-to-strip joints the effects of the different energy absorption on the process are pointed out.

M. Brandner; G. Seibold; C. Chang; F. Dausinger; H. Hügel

2000-01-01T23:59:59.000Z

211

Process Development of C–N Cross-Coupling and Enantioselective Biocatalytic Reactions for the Asymmetric Synthesis of Niraparib  

Science Journals Connector (OSTI)

§ Department of Chemical Process Development and Commercialization, Merck & Co., Inc., Rahway, New Jersey 07065, United States ... The enzyme poly(ADP-ribose)polymerase (PARP) is involved in a number of cellular processes, one of these being to assist in the repair of single-strand breaks in DNA. ... and reaction modeling; and continuous processing/process intensification. ...

Cheol K. Chung; Paul G. Bulger; Birgit Kosjek; Kevin M. Belyk; Nelo Rivera; Mark E. Scott; Guy R. Humphrey; John Limanto; Donald C. Bachert; Khateeta M. Emerson

2013-10-25T23:59:59.000Z

212

Low-frequency variability and heat transport in a low-order nonlinear coupled ocean-atmosphere model  

E-Print Network [OSTI]

We formulate and study a low-order nonlinear coupled ocean-atmosphere model with an emphasis on the impact of radiative and heat fluxes and of the frictional coupling between the two components. This model version extends a previous 24-variable version by adding a dynamical equation for the passive advection of temperature in the ocean, together with an energy balance model. The bifurcation analysis and the numerical integration of the model reveal the presence of low-frequency variability (LFV) concentrated on and near a long-periodic, attracting orbit. This orbit combines atmospheric and oceanic modes, and it arises for large values of the meridional gradient of radiative input and of frictional coupling. Chaotic behavior develops around this orbit as it loses its stability; this behavior is still dominated by the LFV on decadal and multi-decadal time scales that is typical of oceanic processes. Atmospheric diagnostics also reveals the presence of predominant low- and high-pressure zones, as well as of a subtropical jet; these features recall realistic climatological properties of the oceanic atmosphere. Finally, a predictability analysis is performed. Once the decadal-scale periodic orbits develop, the coupled system's short-term instabilities --- as measured by its Lyapunov exponents --- are drastically reduced, indicating the ocean's stabilizing role on the atmospheric dynamics. On decadal time scales, the recurrence of the solution in a certain region of the invariant subspace associated with slow modes displays some extended predictability, as reflected by the oscillatory behavior of the error for the atmospheric variables at long lead times.

Stéphane Vannitsem; Jonathan Demaeyer; Lesley De Cruz; Michael Ghil

2014-12-01T23:59:59.000Z

213

Coupling of the model reduction technique with the lattice Boltzmann method for combustion simulations  

SciTech Connect (OSTI)

A new framework of simulation of reactive flows is proposed based on a coupling between accurate reduced reaction mechanism and the lattice Boltzmann representation of the flow phenomena. The model reduction is developed in the setting of slow invariant manifold construction, and the simplest lattice Boltzmann equation is used in order to work out the procedure of coupling of the reduced model with the flow solver. Practical details of constructing slow invariant manifolds of a reaction system under various thermodynamic conditions are reported. The proposed method is validated with the two-dimensional simulation of a premixed counterflow flame in the hydrogen-air mixture. (author)

Chiavazzo, Eliodoro [Aerothermochemistry and Combustion Systems Lab, ETH Zurich, 8092 Zurich (Switzerland); Department of Energetics, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin (Italy); Karlin, Iliya V. [Aerothermochemistry and Combustion Systems Lab, ETH Zurich, 8092 Zurich (Switzerland); School of Engineering Sciences, University of Southampton, SO17 1BJ Southampton (United Kingdom); Gorban, Alexander N. [Department of Mathematics, University of Leicester, LE1 7RH Leicester (United Kingdom); Boulouchos, Konstantinos [Aerothermochemistry and Combustion Systems Lab, ETH Zurich, 8092 Zurich (Switzerland)

2010-10-15T23:59:59.000Z

214

Coupled Ocean–Atmosphere Dynamical Processes in the Tropical Indian and Pacific Oceans and the TBO  

Science Journals Connector (OSTI)

The transitions (from relatively strong to relatively weak monsoon) in the tropospheric biennial oscillation (TBO) occur in northern spring for the south Asian or Indian monsoon and northern fall for the Australian monsoon involving coupled land–...

Gerald A. Meehl; Julie M. Arblaster; Johannes Loschnigg

2003-07-01T23:59:59.000Z

215

PROCESS MODEL FOR THE PRODUCTION OF SYNGAS VIA HIGH TEMPERATURE CO-ELECTROLYSIS  

SciTech Connect (OSTI)

A process model has been developed to evaluate the potential performance of a large-scale high-temperature coelectrolysis plant for the production of syngas from steam and carbon dioxide. The coelectrolysis process allows for direct electrochemical reduction of the steam – carbon dioxide gas mixture, yielding hydrogen and carbon monoxide, or syngas. The process model has been developed using the HYSYS systems analysis code. Using this code, a detailed process flowsheet has been defined that includes all the components that would be present in an actual plant such as pumps, compressors, heat exchangers, turbines, and the electrolyzer. Since the electrolyzer is not a standard HYSYS component, a custom one-dimensional coelectrolysis model was developed for incorporation into the overall HYSYS process flowsheet. The 1-D coelectrolysis model assumes local chemical equilibrium among the four process-gas species via the shift reaction. The electrolyzer model allows for the determination of coelectrolysis outlet temperature, composition (anode and cathode sides), mean Nernst potential, operating voltage and electrolyzer power based on specified inlet gas flow rates, heat loss or gain, current density, and cell area-specific resistance. The one-dimensional electrolyzer model was validated by comparison with results obtained from a fully 3-D computational fluid dynamics model developed using FLUENT, and by comparison to experimental data. This paper provides representative results obtained from the HYSYS flowsheet model for a 300 MW coelectrolysis plant, coupled to a high-temperature gas-cooled nuclear reactor. The coelectrolysis process, coupled to a nuclear reactor, provides a means of recycling carbon dioxide back into a useful liquid fuel. If the carbon dioxide source is based on biomass, the entire process would be climate neutral.

M. G. McKellar; J. E. O'Brien; C. M. Stoots; G. L. Hawkes

2007-11-01T23:59:59.000Z

216

A SYSTEMS APPROACH TO MATHEMATICAL MODELING OF INDUSTRIAL PROCESSES  

E-Print Network [OSTI]

/or partial automation of the creative modeling process. Model Generation is a new modeling paradigm designed specifically for rapid modeling of large multi-scale systems in the industrial practice. It proposes model. Keywords: Dynamic and continuous/discrete simulation, computer-aided modeling, symbolic

Linninger, Andreas A.

217

A coupled THC model of the FEBEX in situ test with bentonite swelling and chemical and thermal osmosis  

SciTech Connect (OSTI)

The performance assessment of a geological repository for radioactive waste requires quantifying the geochemical evolution of the bentonite engineered barrier. This barrier will be exposed to coupled thermal (T), hydrodynamic (H), mechanical (M) and chemical (C) processes. This paper presents a coupled THC model of the FEBEX (Full-scale Engineered Barrier EXperiment) in situ test which accounts for bentonite swelling and chemical and thermal osmosis. Model results attest the relevance of thermal osmosis and bentonite swelling for the geochemical evolution of the bentonite barrier while chemical osmosis is found to be almost irrelevant. The model has been tested with data collected after the dismantling of heater 1 of the in situ test. The model reproduces reasonably well the measured temperature, relative humidity, water content and inferred geochemical data. However, it fails to mimic the solute concentrations at the heater-bentonite and bentonite-granite interfaces because the model does not account for the volume change of bentonite, the CO{sub 2}(g) degassing and the transport of vapor from the bentonite into the granite. The inferred HCO{sub 3}{sup -} and pH data cannot be explained solely by solute transport, calcite dissolution and protonation/deprotonation by surface complexation, suggesting that such data may be affected also by other reactions.

Zheng, L.; Samper, J.; Montenegro, L.

2011-04-01T23:59:59.000Z

218

The development of a cognitive process-oriented correlation model  

E-Print Network [OSTI]

OF SCIENCE December 1988 Major Subject: Curriculum and Instruction THE DEVELOPMENT OF A COGNITIVE PROCESS-ORIENTED CORRELATION MODEL A Thesis by RICHARD JAMES KNEUVEN Approved as to style and content by: P r c'a exander ( r of Committee ) David...-processing correlation model might be translated into a secondary school curriculum. In an attempt to identify underlying cognitive processes that could provide a basis for a process-oriented correlation model, several areas of literature were reviewed. This thesis...

Kneuven, Richard James

1988-01-01T23:59:59.000Z

219

Hydro-Mechanical Coupling in Damaged Porous Media Containing Isolated Cracks or/and Vugs: Model and Computations  

E-Print Network [OSTI]

Hydro-Mechanical Coupling in Damaged Porous Media Containing Isolated Cracks or/and Vugs: Model In this paper we present the development of the macroscopic model describing the hydro-mechanical coupling model in the micro-porous domain saturated by a fluid. In the crack/vug domain the Stokes equation

Paris-Sud XI, Université de

220

A Coupled Modeling System to Simulate Water Resources in the Rio Grande Basin  

SciTech Connect (OSTI)

Limited availability of fresh water in arid and semi-arid regions of the world requires prudent management strategies from accurate, science-based assessments. These assessments demand a thorough understanding of the hydrologic cycle over long time periods within the individual water-sheds that comprise large river basins. Measurement and simulation of the hydrologic cycle is a tremendous challenge, involving a coupling between global to regional-scale atmospheric precipitation processes with regional to local-scale land surface and subsurface water transport. Los Alamos National Laboratory is developing a detailed modeling system of the hydrologic cycle and applying this tool at high resolution to assess the water balance within the upper Rio Grande river basin. The Rio Grande is a prime example of a river system in a semiarid environment, with a high demand from agricultural, industrial, recreational, and municipal interests for its water supply. Within this river basin, groundwater supplies often augment surface water. With increasing growth projected throughout the river basin, however, these multiple water users have the potential to significantly deplete groundwater resources, thereby increasing the dependence on surface water resources.

Bossert, J.E.; Breshears, D.D.; Campbell, K.; Costigan, K.R.; Greene, R.K.; Keating, E.H.; Kleifgen, L.M.; Langley, D.L.; Martens, S.N.; Sanderson, J.G.; Springer, E.P.; Stalker, J.R.; Tartakovsky, D.M.; Winter, C.L.; Zyvoloski, G.A.

1999-01-11T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

Soil Carbon Modeling (Mac Post) A. Rothamsted model carbon pools and processes. Their approximate equivalents for the EBIS sample processing  

E-Print Network [OSTI]

' soil horizon show that model improvements need to be made to capture observed soil carbon cyclingSoil Carbon Modeling (Mac Post) A. Rothamsted model carbon pools and processes. Their approximate and transport processes. Testing and improvement of soil carbon cycling models is a key anticipated output

222

Dynamical Coupled-Channels Model Analysis of ?-N Scattering and Electromagnetic Pion Production Reactions  

E-Print Network [OSTI]

The ability of the coupled-channels model (MSL) developed in recently in Ref. \\cite{msl} to account simultaneously for the $\\pi N$ scattering data and the $\\pi$ photoproduction reactions on the nucleon is presented. An accurate description of $\\pi N$ scattering has been obtained. A preliminary description of $\\pi$ photoproduction is also discussed.

B. Julia-Diaz

2007-12-01T23:59:59.000Z

223

How does trench coupling lead to mountain building in the Subandes? A viscoelastoplastic finite element model  

E-Print Network [OSTI]

How does trench coupling lead to mountain building in the Subandes? A viscoelastoplastic finite element model Gang Luo1 and Mian Liu1 Received 10 June 2008; revised 3 December 2008; accepted 2 February cause of the Andean mountain building. The present-day crustal shortening in the Andes is clear from

Liu, Mian

224

An improved numerical scheme for a coupled system to model soil erosion and polydispersed sediments transport  

E-Print Network [OSTI]

An improved numerical scheme for a coupled system to model soil erosion and polydispersed sediments, the positivity of both water depth and sediment concentrations. Recently, a well-balanced MUSCL-Hancock scheme step is required to ensure the positivity of sediment concentrations. The main result of this paper

Boyer, Edmond

225

Coupling schemes for modeling hydraulic fracture propagation using the XFEM Elizaveta Gordeliy, Anthony Peirce  

E-Print Network [OSTI]

Coupling schemes for modeling hydraulic fracture propagation using the XFEM Elizaveta Gordeliy August 2012 Accepted 18 August 2012 Available online 15 September 2012 Keywords: XFEM Hydraulic fractures and the Dirichlet to Neumann (DN) map with Oðh� accuracy. For hydraulic fracture problems with a lag separating

Peirce, Anthony

226

Intraseasonal Eastern Pacific Precipitation and SST Variations in a GCM Coupled to a Slab Ocean Model  

E-Print Network [OSTI]

Intraseasonal Eastern Pacific Precipitation and SST Variations in a GCM Coupled to a Slab Ocean-Schubert convection to a slab ocean model (SOM) improves the simulation of eastern Pacific convection during and ocean make eastern Pacific low-level circulation anomalies more complex in the SOM simulation than

Maloney, Eric

227

Intraseasonal Eastern Pacific Precipitation and SST Variations in a GCM Coupled to a Slab Ocean Model  

E-Print Network [OSTI]

Intraseasonal Eastern Pacific Precipitation and SST Variations in a GCM Coupled to a Slab Ocean­Schubert convection to a slab ocean model (SOM) improves the simulation of eastern Pacific convection during and ocean make eastern Pacific low­level circulation anomalies more complex in the SOM simulation than

Maloney, Eric

228

ISW-LSS CROSS-CORRELATION IN COUPLED DARK ENERGY MODELS WITH MASSIVE NEUTRINOS  

SciTech Connect (OSTI)

We provide an exhaustive analysis of the Integrated Sachs-Wolfe (ISW) effect in the context of coupled dark energy cosmologies where a component of massive neutrinos is also present. We focus on the effects of both the coupling between dark matter and dark energy and of the neutrino mass on the cross-correlation between galaxy/quasar distributions and ISW effect. We provide a simple expression to appropriately rescale the galaxy bias when comparing different cosmologies. Theoretical predictions of the cross-correlation function are then compared with observational data. We find that, while it is not possible to distinguish among the models at low redshifts, discrepancies between coupled models and {Lambda}CDM increase with z. In spite of this, current data alone does not seem able to distinguish between coupled models and {Lambda}CDM. However, we show that upcoming galaxy surveys will permit tomographic analysis that will allow us to better discriminate among the models. We discuss the effects on cross-correlation measurements of ignoring galaxy bias evolution, b(z), and magnification bias correction and provide fitting formulae for b(z) for the cosmologies considered. We compare three different tomographic schemes and investigate how the expected signal-to-noise ratio, S/N, of the ISW-LSS cross-correlation changes when increasing the number of tomographic bins. The dependence of S/N on the area of the survey and the survey shot noise is also discussed.

Mainini, Roberto [INAF-Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monte Porzio Catone, Rome (Italy); Mota, David F. [Institute of Theoretical Astrophysics, University of Oslo, Box 1029, 0315 Oslo (Norway)

2012-01-01T23:59:59.000Z

229

Changes in Temperature and Precipitation Extremes in the IPCC Ensemble of Global Coupled Model Simulations  

E-Print Network [OSTI]

Changes in Temperature and Precipitation Extremes in the IPCC Ensemble of Global Coupled Model September 2006) ABSTRACT Temperature and precipitation extremes and their potential future changes on Climate Change (IPCC) diagnostic exercise for the Fourth Assessment Report (AR4). Climate extremes

230

Final Report Coupling in silico microbial models with reactive transport models to predict the fate of contaminants in the subsurface.  

SciTech Connect (OSTI)

This project successfully accomplished its goal of coupling genome-scale metabolic models with hydrological and geochemical models to predict the activity of subsurface microorganisms during uranium bioremediation. Furthermore, it was demonstrated how this modeling approach can be used to develop new strategies to optimize bioremediation. The approach of coupling genome-scale metabolic models with reactive transport modeling is now well enough established that it has been adopted by other DOE investigators studying uranium bioremediation. Furthermore, the basic principles developed during our studies will be applicable to much broader investigations of microbial activities, not only for other types of bioremediation, but microbial metabolism in diversity of environments. This approach has the potential to make an important contribution to predicting the impact of environmental perturbations on the cycling of carbon and other biogeochemical cycles.

Lovley, Derek R.

2012-10-31T23:59:59.000Z

231

$b \\to s \\ell\\overline{\\ell}$ process and multi-Higgs doublet model  

E-Print Network [OSTI]

Rare $b$ decay processes are analyzed in the multi-Higgs doublet model. Taking account of the constraint from the $b\\to s \\gamma$ process, the branching ratio and the forward-backward asymmetry of the final leptons for the $b\\to s \\ell^+ \\ell^-$ process are calculated. It is shown that the branching ratio can be a few times larger than the standard model prediction and the asymmetry can be significantly different from that in the standard model. Combining these observable quantities it is possible to determine complex coupling constants associated with the charged Higgs mixing matrix. The CP violating charge asymmetry in the $b\\to s \\ell^+ \\ell^-$ process and the branching ratio of the $b\\to s \

Yasuhiro Okada; Yasuhiro Shimizu; Minoru Tanaka

1997-04-03T23:59:59.000Z

232

Development of Fully Coupled Aeroelastic and Hydrodynamic Models for Offshore Wind Turbines: Preprint  

SciTech Connect (OSTI)

Aeroelastic simulation tools are routinely used to design and analyze onshore wind turbines, in order to obtain cost effective machines that achieve favorable performance while maintaining structural integrity. These tools employ sophisticated models of wind-inflow; aerodynamic, gravitational, and inertial loading of the rotor, nacelle, and tower; elastic effects within and between components; and mechanical actuation and electrical responses of the generator and of control and protection systems. For offshore wind turbines, additional models of the hydrodynamic loading in regular and irregular seas, the dynamic coupling between the support platform motions and wind turbine motions, and the dynamic characterization of mooring systems for compliant floating platforms are also important. Hydrodynamic loading includes contributions from hydrostatics, wave radiation, and wave scattering, including free surface memory effects. The integration of all of these models into comprehensive simulation tools, capable of modeling the fully coupled aeroelastic and hydrodynamic responses of floating offshore wind turbines, is presented.

Jonkman, J. M.; Sclavounos, P. D.

2006-01-01T23:59:59.000Z

233

Sensitivity of Optimal Operation of an Activated Sludge Process Model  

E-Print Network [OSTI]

Sensitivity of Optimal Operation of an Activated Sludge Process Model Antonio Araujo, Simone sensitivity analysis of optimal operation conducted on an activated sludge process model based on the test.[7] applied a systematic procedure for control structure design of an activated sludge process

Skogestad, Sigurd

234

Reactor Modeling and Recipe Optimization of Polyether Polyol Processes  

E-Print Network [OSTI]

Reactor Modeling and Recipe Optimization of Polyether Polyol Processes Spring 2013 EWO Meeting Yisu.M. Wassick. Reactor Modeling and Recipe Optimization of Polyether Polyol Processes: Polypropylene Glycol Project timeline Development of systematic optimization methods of batch processes Nov. 2009 - Dec. 2011

Grossmann, Ignacio E.

235

Modeling and simulation of film blowing process  

E-Print Network [OSTI]

, their work does not include crystallization kinetics, hence, restricted to amorphous polymers. Cao and Campbell?s predictions of bubble radius, temperature, and velocity profiles are in reasonably good agreement with Gupta?s (1980) experimental measurements.... . . . . . . . . . . . . . 95 V Process conditions used for the analysis of Exxon data. . . . . . . . . 99 VI The influence of radiation heat transfer on the process. . . . . . . . . 171 x LIST OF FIGURES FIGURE Page 1 Schematic of a typical film blowing process...

Mayavaram, Ravisankar S.

2005-08-29T23:59:59.000Z

236

A General Process Model of Sustainability  

Science Journals Connector (OSTI)

The intellectual roots of sustainability and some of its theoretical consequences for sustainable development have been reviewed, and need not be here. ... Just as material processes are governed by the first and second laws of thermodynamics and the theory of rate processes, the general theory of sustainability is based on these three concepts as applied to dynamic as well as steady-state processes. ... Basing the theory on the twin pillars of thermodynamics and rate processes enables it to be generalized across physical-metabolic and social-economic phenomena. ...

Michael Neuman; Stuart W. Churchill

2011-01-18T23:59:59.000Z

237

Fractional Dynamical Model for the Generation of ECG like Signals from Filtered Coupled Van-der Pol Oscillators  

E-Print Network [OSTI]

In this paper, an incommensurate fractional order (FO) model has been proposed to generate ECG like waveforms. Earlier investigation of ECG like waveform generation is based on two identical Van-der Pol (VdP) family of oscillators which are coupled by time delays and gains. In this paper, we suitably modify the three state equations corresponding to the nonlinear cross-product of states, time delay coupling of the two oscillators and low-pass filtering, using the concept of fractional derivatives. Our results show that a wide variety of ECG like waveforms can be simulated from the proposed generalized models, characterizing heart conditions under different physiological conditions. Such generalization of the modelling of ECG waveforms may be useful to understand the physiological process behind ECG signal generation in normal and abnormal heart conditions. Along with the proposed FO models, an optimization based approach is also presented to estimate the VdP oscillator parameters for representing a realistic ECG like signal.

Saptarshi Das; Koushik Maharatna

2014-10-20T23:59:59.000Z

238

Chemical Process Modeling in Modelica Ali Baharev Arnold Neumaier  

E-Print Network [OSTI]

The object-oriented component-based modeling methodology in Modelica (FRITZSON [13]) is well- suitedChemical Process Modeling in Modelica Ali Baharev Arnold Neumaier Fakultät für Mathematik for general-purpose chemical process modeling have been built. Multi- ple steady-states in ideal two

Neumaier, Arnold

239

A three-dimensional phase field model coupled with lattice kinetics solver for modeling crystal growth in furnaces with accelerated crucible rotation and traveling magnetic field  

SciTech Connect (OSTI)

In this study, which builds on other related work, we present a new three-dimensional numerical model for crystal growth in a vertical solidification system. This model accounts for buoyancy, accelerated crucible rotation technique (ACRT), and traveling magnetic field (TMF) induced convective flow and their effect on crystal growth and the chemical component's transport process. The evolution of the crystal growth interface is simulated using the phase field method. A semi-implicit lattice kinetics solver based on the Boltzmann equation is employed to model the unsteady incompressible flow. A one-way coupled concentration transport model is used to simulate the component fraction variation in both the liquid and solid phases, which can be used to check the quality of the crystal growth.

Lin, Guang; Bao, Jie; Xu, Zhijie

2014-11-01T23:59:59.000Z

240

The effect of self-disclosure and empathic responding on intimacy: testing an interpersonal process model of intimacy using an observational coding system  

E-Print Network [OSTI]

the evidence for the interpersonal process model of intimacy described by Reis and Shaver (1988), which proposes that self-disclosure and empathic responding are the basis of intimate interactions. The sample consisted of 108 community couples who completed...

Mitchell, Alexandra Elizabeth

2007-09-17T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

Coupling characteristics of the ITER relevant lower hybrid antenna in Tore Supra: experiments and modelling  

SciTech Connect (OSTI)

A new concept of lower hybrid antenna for current drive has been proposed for ITER [Bibet et al, Nuclear Fusion 1995]: the Passive Active Multijunction (PAM) antenna that relies on a periodic combination of active and passive waveguides. An actively cooled PAM antenna at 3.7 GHz has been recently installed on the tokamak Tore Supra. The paper summarizes the comprehensive experimental characterization of the linear coupling properties of the PAM antenna to the Tore Supra plasmas. These experimental results are systematically compared with the linear wave coupling theory via the linear ALOHA code. Good agreement between experimental results and ALOHA have been obtained. The detailed validation of the coupling modelling is an important step toward the validation of the PAM concept in view of further optimizing the electromagnetic properties of the future ITER antenna.

Preynas, M.; Ekedahl, A.; Fedorczak, N.; Goniche, M.; Guilhem, D.; Gunn, J. P.; Hillairet, J.; Litaudon, X. [CEA, IRFM, 13108 Saint Paul lez Durance (France); Associacao Euratom-IST, Centro de Fusao Nuclear 1049-001 Lisboa (Portugal)

2011-12-23T23:59:59.000Z

242

Scale-out of Microreactor Stacks for Portable and Distributed Processing: Coupling of Exothermic and Endothermic Processes for Syngas Production  

Science Journals Connector (OSTI)

Computational fluid dynamics (CFD) simulations are used to simulate stacks of different sizes, to understand nonlinear effects that arise in scaleout of microchemical systems. As an example process, syngas production from methane is studied using a ...

Matthew S. Mettler; Georgios D. Stefanidis; Dionisios G. Vlachos

2010-06-11T23:59:59.000Z

243

Modeling the coupling of reaction kinetics and hydrodynamics in a collapsing cavity  

SciTech Connect (OSTI)

We introduce a model of cavitation based on the multiphase Lattice Boltzmann method (LBM) that allows for coupling between the hydrodynamics of a collapsing cavity and supported solute chemical species. We demonstrate that this model can also be coupled to deterministic or stochastic chemical reactions. In a two-species model of chemical reactions (with a major and a minor specie), the major difference observed between the deterministic and stochastic reactions takes the form of random fluctuations in concentration of the minor species. We demonstrate that advection associated with the hydrodynamics of a collapsing cavity leads to highly inhomogeneous concentration of solutes. In turn these inhomogeneities in concentration may lead to significant increase in concentration-dependent reaction rates and can result in a local enhancement in the production of minor species.

Mishra, Sudib [University of Arizona; Deymier, Pierre [University of Arizona; Muralidharan, Krishna [University of Arizona; Frantziskonis, G. [University of Arizona; Pannala, Sreekanth [ORNL; Simunovic, Srdjan [ORNL

2010-01-01T23:59:59.000Z

244

Chemical Models for Aqueous Biodynamical Processes  

E-Print Network [OSTI]

The proton inventory method was applied to the study of three processes: the viscous flow of water, the neutral hydrolysis of esters, and the exchange reaction between aqueous sodium ion and the carboxylic exchanger Amberlite ...

Mata-Segreda, Julio F.

1975-05-01T23:59:59.000Z

245

Feedback control of HfO{sub 2} etch processing in inductively coupled Cl{sub 2}/N{sub 2}/Ar plasmas  

SciTech Connect (OSTI)

The etch rate of HfO{sub 2} etch processing has been feedback controlled in inductively coupled Cl{sub 2}/N{sub 2}/Ar plasmas. The ion current and the root mean square rf voltage on the wafer stage, which are measured using a commercial impedance meter connected to the wafer stage, are chosen as controlled variables because the positive-ion flux and ion energy incident upon the wafer surface are the key factors that determine the etch rate. Two 13.56 MHz rf generators are used to adjust the inductively coupled plasma power and bias power which control ion density and ion energy, respectively. The adopted HfO{sub 2} etch processing used rather low rf voltage. The ion-current value obtained by the power/voltage method is underestimated, so the neural-network model was developed to assist estimating the correct ion-current value. The experimental results show that the etch-rate variation of the closed-loop control is smaller than that of the open-loop control. However, the first wafer effect cannot be eliminated using closed-loop control and thus to achieve a constant etch rate, the chamber-conditioning procedure is required in this etch processing.

Lin Chaung; Leou, K.-C.; Li, T.-C.; Lee, L.-S.; Tzeng, P.-J. [Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan 30043 (China); Electronic Research and Service Organization, Industrial Technology Research Institute, Hsinchu, Taiwan 310 (China)

2008-09-15T23:59:59.000Z

246

Bayesian variable selection in clustering via dirichlet process mixture models  

E-Print Network [OSTI]

simultane- ously. I use Dirichlet process mixture models to define the cluster structure and to introduce in the model a latent binary vector to identify discriminating variables. I update the variable selection index using a Metropolis algorithm and obtain...

Kim, Sinae

2007-09-17T23:59:59.000Z

247

Adjoint modeling for atmospheric pollution process sensitivity at regional scale  

E-Print Network [OSTI]

Adjoint modeling for atmospheric pollution process sensitivity at regional scale Laurent Menut; 0345 Atmospheric Composition and Structure: Pollution--urban and regional (0305); 3210 Mathematical: atmospheric pollution, tropospheric ozone, urban pollution peaks, adjoint modeling, sensitivity Citation

Menut, Laurent

248

Predicting Coupled Ocean-Atmosphere Modes with a Climate Modeling Hierarchy -- Final Report  

SciTech Connect (OSTI)

The goal of the project was to determine midlatitude climate predictability associated with tropical-extratropical interactions on interannual-to-interdecadal time scales. Our strategy was to develop and test a hierarchy of climate models, bringing together large GCM-based climate models with simple fluid-dynamical coupled ocean-ice-atmosphere models, through the use of advanced probabilistic network (PN) models. PN models were used to develop a new diagnostic methodology for analyzing coupled ocean-atmosphere interactions in large climate simulations made with the NCAR Parallel Climate Model (PCM), and to make these tools user-friendly and available to other researchers. We focused on interactions between the tropics and extratropics through atmospheric teleconnections (the Hadley cell, Rossby waves and nonlinear circulation regimes) over both the North Atlantic and North Pacific, and the ocean’s thermohaline circulation (THC) in the Atlantic. We tested the hypothesis that variations in the strength of the THC alter sea surface temperatures in the tropical Atlantic, and that the latter influence the atmosphere in high latitudes through an atmospheric teleconnection, feeding back onto the THC. The PN model framework was used to mediate between the understanding gained with simplified primitive equations models and multi-century simulations made with the PCM. The project team is interdisciplinary and built on an existing synergy between atmospheric and ocean scientists at UCLA, computer scientists at UCI, and climate researchers at the IRI.

Michael Ghil, UCLA; Andrew W. Robertson, IRI, Columbia Univ.; Sergey Kravtsov, U. of Wisconsin, Milwaukee; Padhraic Smyth, UC Irvine

2006-08-04T23:59:59.000Z

249

The modelling of biochemical-thermal coupling effect on gas generation and transport in MSW landfill  

Science Journals Connector (OSTI)

The landfill gas generation was investigated based on the theories of the thermodynamics, microbial dynamics and chemical dynamics. The coupling model was developed for describing the gas transport and heat release. And the relationship between the gas generation rate and the temperature was proposed. The parameters in the gas generation model were obtained by bioreactor test in order to evaluate the volume of gas production of the Erfeishan landfill in China. The simulation results shown that the operating life of the landfill will be overestimated if the model does not consider the thermal effect during degradation of the solid substrate.

Liu Lei; Liang Bing; Xue Qiang; Zhao Ying; Yang Chun

2011-01-01T23:59:59.000Z

250

Toward self-describing and workflow integrated Earth system models: A coupled atmosphere-ocean modeling system application  

Science Journals Connector (OSTI)

The complexity of Earth system models and their applications is increasing as a consequence of scientific advances, user demand, and the ongoing development of computing platforms, storage systems and distributed high-resolution observation networks. Multi-component Earth system models need to be redesigned to make interactions among model components and other applications external to the modeling system easier. To that end, the common component interfaces of Earth system models can be redesigned to increase interoperability between models and other applications such as various web services, data portals and science gateways. The models can be made self-describing so that the many configuration, build options and inputs of a simulation can be recorded. In this paper, we present a coupled modeling system that includes the proposed methodology to create self-describing models with common model component interfaces. The designed coupled atmosphere-ocean modeling system is also integrated into a scientific workflow system to simplify routine modeling tasks and relationships between these tasks and to demonstrate the enhanced interoperability between different technologies and components. Later on, the work environment is tested using a realistic Earth system modeling application. As can be seen through this example, a layered design for collecting provenance and metadata has the added benefit of documenting a run in far greater detail than before. In this way, it facilitates exploration and understanding of simulations and leads to possible reproducibility. In addition to designing self-describing Earth system models, the regular modeling tasks are also simplified and automated by using a scientific workflow which provides meaningful abstractions for the model, computing environment and provenance/metadata collection mechanisms. Our aim here is to solve a specific instance of a complex model integration problem by using a framework and scientific workflow approach together. The reader may also note that the methods presented in this paper might be also generalized to other types of Earth system models, leading to improved ease of use and flexibility. The initial results also show that the coupled atmosphere-ocean model, which is controlled by the designed workflow environment, is able to reproduce the Mediterranean Sea surface temperature when it is compared with the used CCSM3 initial and boundary conditions.

Ufuk Utku Turuncoglu; Nuzhet Dalfes; Sylvia Murphy; Cecelia DeLuca

2013-01-01T23:59:59.000Z

251

Offshore floating vertical axis wind turbines, dynamics modelling state of the art. Part III: Hydrodynamics and coupled modelling approaches  

Science Journals Connector (OSTI)

Abstract The need to further exploit offshore wind resources has pushed offshore wind farms into deeper waters, requiring the use of floating support structures to be economically sustainable. The use of conventional wind turbines may not continue to be the optimal design for floating applications. Therefore it is important to assess other alternative configurations in this context. Vertical axis wind turbines (VAWTs) are one promising configuration, and it is important to first understand the coupled and relatively complex dynamics of floating \\{VAWTs\\} to assess the technical feasibility. As part of this task, a series of articles have been developed to present a comprehensive literature review covering the various areas of engineering expertise required to understand the coupled dynamics involved in floating VAWTs. This third article focuses on approaches to develop an efficient coupled model of dynamics (considering aerodynamics, hydrodynamics, structural and mooring line dynamics, and control dynamics) for floating VAWTs, as well as suitable ‘semi-analytical’ hydrodynamic models for this type of coupled dynamics models. Emphasis is also placed on utilising computationally efficient models and programming strategies. A comparison of the various forces acting on a floating VAWT with the three main floating support structure (spar, semi-submersible and tension-leg-platform) is also presented to highlight the relative dominant forces and hence importance of model accuracy representing these forces. Lastly a concise summary covering this series of articles is presented to give the reader an overview of this interdisciplinary research area. This article has been written both for researchers new to this research area, outlining underlying theory whilst providing a comprehensive review of the latest work, and for experts in this area, providing a comprehensive list of the relevant references where the details of modelling approaches may be found.

Michael Borg; Maurizio Collu

2014-01-01T23:59:59.000Z

252

Dynamics of strong-coupling models for cuprate superconductors: Exact results on finite lattices  

SciTech Connect (OSTI)

We discuss recent applications of exact numerical continued fraction expansion (CFE) techniques to calculate dynamical correlation functions of various strong-coupling models related to the high-temperature cuprate superconductors. For the two-dimensional square-lattice spin-1/2 Heisenberg antiferromagnet, we present exact results for the zero-temperature dynamical structure factor on finite-sized lattices and compare them to approximate results from a Schwinger boson mean-field theory, recently proposed by Arovas and Auerbach. We find that the mean-field theory represents a very good approximation to the exact spin excitation spectra and to the static spin correlations. We then investigation the dynamical spin-spin structure factor and the single-particle spectral function for finite model clusters with dopant induced hole-type charge carriers, in the strong-coupling limit of both the single-band Hubbard model (t-J-model) and the three-band Hubbard model (Kondo-Heisenberg model). Our results are consistent with the physical picture recently proposed by Zhang and Rice which implies an approximate mapping of the low-energy states in the three-band model onto an effective single-band theory. 33 refs., 4 figs.

Schuettler, H.B.; Chen, C.-X. (Georgia Univ., Athens, GA (USA). Center for Simulational Physics); Fedro, A.J. (Argonne National Lab., IL (USA) Northern Illinois Univ., Dekalb, IL (USA). Dept. of Physics)

1989-01-01T23:59:59.000Z

253

Fitting Non-Minimally Coupled Scalar Models to Gold SnIa Dataset  

E-Print Network [OSTI]

Non-minimally coupled theories of special potentials are analyzed numerically. Such theories yield equations of state $\\omegadataset, we obtain results comparable with other models. A potential of the form $V(\\phi)=V_0e^{a_1\\phi^2}$ yields $\\chi^2_{min}=170.127$. Similar results are obtained for potentials of the form $V(\\phi)=V_0+a_1\\phi^n$.

Mingxing Luo; Qiping Su

2005-08-18T23:59:59.000Z

254

Computational modelling of transport phenomena in high energy materials processing application: large eddy simulation and parallelisation  

Science Journals Connector (OSTI)

A comprehensive three-dimensional numerical model is presented in order to address the coupled turbulent momentum, heat and species transport during molten metal-pool convection in association with continuous evolution of solid-liquid interface typically encountered in high energy materials processing applications. The turbulent aspect is handled by a large eddy simulation (LES) model and the phase changing phenomena is taken care of by a modified enthalpy-porosity technique. The proposed finite volume based LES model is subsequently parallelised for effective computational economy. To demonstrate the effectiveness of the present model, a systematic analysis is subsequently carried out to simulate a typical high power laser surface alloying process, where the effects of turbulent transport can actually be realised.

Dipankar Chatterjee

2011-01-01T23:59:59.000Z

255

Removal of hydrophobic Volatile Organic Compounds1 in an integrated process coupling Absorption and2  

E-Print Network [OSTI]

technology like photochemical oxidation shows high efficiency70 but is also high energy-consuming; moreover processes involve water as absorbent, they appear not always really efficient for the treatment of24 of the process, hydrophobic VOC27 absorption in a gas-liquid contactor, and biodegradation in the TPPB. VOC

Boyer, Edmond

256

An information modeling framework for process planning  

E-Print Network [OSTI]

planning links design and manufacture and has been recog- nized as one of the key elements in Concurrent Engineering. It serves as a crucial integrator for Computer Integrated Manufacturing (CIM). Decomposition of the com- plex decision making in process... framework and its development methodology has potential uses in other aspects of CIM and Concurrent engineering. To My Parents. ACKNOWLEDGMENTS I would like to primarily, thank both Dr. Richard J. Mayer and Dr. Richard A. Wysk for their guidance...

Atreya, Dinesh S.

2012-06-07T23:59:59.000Z

257

Business Process Modeling and Agility Nancy Alexopoulou1  

E-Print Network [OSTI]

was to investigate business process agility and develop modeling approaches that ensure agility in business process a comprehensive and systematic analysis of enterprise agility, a viewpoint-oriented architecture was developed], [6]). Agility of business processes is intimately related to the approach used for the development

Kouroupetroglou, Georgios

258

Coupled-channel Treatment of Isobaric Analog Resonances in (p,p?) Capture Processes  

Science Journals Connector (OSTI)

Abstract With the advent of nuclear reactions on unstable isotopes, there has been a renewed interest in using isobaric analogue resonances (IAR) as a tool for probing the nuclear structure. The position and width of isobaric analogue resonances in nucleon-nucleus scattering are accurate and detailed indicators of the positions of resonances and bound states with good single-particle characters. We report on implementation within our coupled-channels code FRESCO of the charge-exchange interaction term that transforms an incident proton into a neutron. Isobaric analog resonances are seen as peaks in ?-ray spectrum when the proton is transformed into a neutron at an energy near a neutron bound state. The Lane coupled-channels formalism was extended to follow the non-orthogonality of this neutron channel with that configuration of an inelastic outgoing proton, and the target being left in a particle-hole excited state. This is tested for 208Pb, for which good (p,p'?) coincidence data exists.

I.J. Thompson; G. Arbanas

2014-01-01T23:59:59.000Z

259

Process modeling of hydrogen production from municipal solid waste  

SciTech Connect (OSTI)

The ASPEN PLUS commercial simulation software has been used to develop a process model for a conceptual process to convert municipal solid waste (MSW) to hydrogen. The process consists of hydrothermal treatment of the MSW in water to create a slurry suitable as feedstock for an oxygen blown Texaco gasifier. A method of reducing the complicated MSW feed material to a manageable set of components is outlined along with a framework for modeling the stoichiometric changes associated with the hydrothermal treatment process. Model results indicate that 0.672 kmol/s of hydrogen can be produced from the processing of 30 kg/s (2600 tonne/day) of raw MSW. A number of variations on the basic processing parameters are explored and indicate that there is a clear incentive to reduce the inert fraction in the processed slurry feed and that cofeeding a low value heavy oil may be economically attractive.

Thorsness, C.B.

1995-01-01T23:59:59.000Z

260

Deactivation models by fitting the progression of temperature profiles – Coking model for the MTG process in adiabatic reactors  

Science Journals Connector (OSTI)

Abstract A methodology for estimating deactivation models for catalysts in industrial application is proposed. The method applies the movement of the measured axial temperature profile to gain information of the deactivating phenomena. For adiabatic reactors the conditions must be obtained by controlled heat compensation in a reactor furnace. As an example a deactivation model for the industrial methanol-to-gasoline (MTG) process is developed. The deactivation model together with suitable reactor models is a system of coupled partial differential equations with time and spatial coordinate as the independent variables. The unknown model parameters are estimated via a non-linear least square method, by matching predicted axial temperature profiles with measured profiles obtained in a pilot reactor containing a gasoline synthesis test catalyst.

Martin Dan Palis Sørensen

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

Nonlocal collisionless power absorption using effective viscosity model in inductively coupled plasma discharges  

SciTech Connect (OSTI)

Effective viscosity model for inductively coupled plasma (ICP) discharges has been used to calculate the power absorbed inside ICP discharges. It is found that it can be used to calculate collisionless heating, which is a warm plasma effect. The validity of effective viscosity model has been checked by comparing it with kinetic model for warm ICP discharges. For very small plasma lengths, the results of both models are the same. At intermediate lengths where bounce resonance heating is important, results of the two models are not the same. Bounce resonance length given by effective viscosity model does not match very well with that given by the kinetic model. It shows that bounce resonance heating cannot be taken care of accurately using the effective viscosity model. For large plasma length, when driving frequencies are low, power absorbed calculated using the kinetic model is more than that calculated by the effective viscosity model. For high driving frequencies, power absorbed calculated using the kinetic model is less than that calculated by the effective viscosity model. The best match between the results of two models (for large plasma length) is obtained if the combination of plasma density, electron temperature, driving frequency, and speed of light is such that the relation K={omega}{sub p}v{sub th}/{omega}c{approx_equal}1 holds. It is concluded that computationally less extensive effective viscosity model can be used to estimate power absorption in ICP discharges by calibrating it with the help of computationally intensive kinetic model. Once calibration is done a lot of computational effort can be avoided by using effective viscosity model instead of kinetic model.

Aman-ur-Rehman, [Pakistan Institute of Engineering and Applied Sciences, P.O. Nilore, Islamabad 45650 (Pakistan); Lee, J. K. [Department of Electronic and Electrical Engineering, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of)

2009-07-15T23:59:59.000Z

262

Coupled flow and heat transfer in viscoelastic fluid with Cattaneo–Christov heat flux model  

Science Journals Connector (OSTI)

Abstract This letter presents a research for coupled flow and heat transfer of an upper-convected Maxwell fluid above a stretching plate with velocity slip boundary. Unlike most classical works, the new heat flux model, which is recently proposed by Christov, is employed. Analytical solutions are obtained by using the homotopy analysis method (HAM). The effects of elasticity number, slip coefficient, the relaxation time of the heat flux and the Prandtl number on velocity and temperature fields are analyzed. A comparison of Fourier’s Law and the Cattaneo–Christov heat flux model is also presented.

Shihao Han; Liancun Zheng; Chunrui Li; Xinxin Zhang

2014-01-01T23:59:59.000Z

263

Critical region for an Ising model coupled to causal dynamical triangulations  

E-Print Network [OSTI]

A lower and an upper bound are established upon a critical curve for the (annealed) Ising model coupled to two-dimensional causal dynamical triangulations. Using the Fortuin-Kasteleyn (FK) representation of quantum Ising models via path integrals, we determine a region in the quadrant of parameters $\\beta, \\mu>0$ where the critical curve can be located. Moreover, this approach serves to outline a region where the infinite-volume Gibbs measure exist and is unique and a region where the finite-volume Gibbs measure has no weak limit. We also provide lower and upper bounds for the infinite-volume free energy.

José Cerda Hernández

2014-02-13T23:59:59.000Z

264

Coupling traffic models on networks and urban dispersion models for simulating sustainable  

E-Print Network [OSTI]

models for modeling and testing different traffic scenarios, in order to define the impact on air quality it with the urban dispersion model Sirane. Keywords: urban air quality, macroscopic traffic models, road networks, pollutant dispersion models, traffic emissions control. AMS subject classification: 35L65, 35L67, 60K30, 90B

Ceragioli, Francesca

265

Chemical kinetics models for semiconductor processing  

SciTech Connect (OSTI)

Chemical reactions in the gas-phase and on surfaces are important in the deposition and etching of materials for microelectronic applications. A general software framework for describing homogeneous and heterogeneous reaction kinetics utilizing the Chemkin suite of codes is presented. Experimental, theoretical and modeling approaches to developing chemical reaction mechanisms are discussed. A number of TCAD application modules for simulating the chemically reacting flow in deposition and etching reactors have been developed and are also described.

Coltrin, M.E.; Creighton, J.R. [Sandia National Labs., Albuquerque, NM (United States); Meeks, E.; Grcar, J.F.; Houf, W.G. [Sandia National Labs., Livermore, CA (United States); Kee, R.J. [Colorado School of Mines, Golden, CO (United States)

1997-12-31T23:59:59.000Z

266

Computer modeling of the spallation process  

E-Print Network [OSTI]

nuclide the final product was in atomic number, the less accurate the results were. Fermi made a significant contribution to the problem of fragmen- 5 tation in 1950 when he proposed statistical weights for the various combinations of reactions from a... reactions. Other approaches were being developed at the same time E. Fermi was working on his model. Bernardini, et al. , and later Metropolis, 6 7 et al. , brought forth Monte Carlo computer programs that followed an incident particle mathematically...

Walker, Wayne Claire

2012-06-07T23:59:59.000Z

267

An Online Coupled Two Way Interactive Modelling Study of Air Pollution Over Europe and Mediterranean  

Science Journals Connector (OSTI)

During the last decade, the efforts in the field of atmospheric modeling have been directed towards a joint ‘online’ approach of the meteorological and chemical processes in order to treat, in an integrated way, ...

Jonilda Kushta; Stavros Solomos…

2014-01-01T23:59:59.000Z

268

SURVEY, ANALYSIS AND VALIDATION OF INFORMATION FOR BUSINESS PROCESS MODELING  

E-Print Network [OSTI]

implementation. In the past, the business has been only represented with hierarchical models business or outsourcing opportunities. ­ To develop an Information systems Architecture, that uses in the future. The process of modeling these two approaches is not the same. The As Is modeling follows a bottom

269

Evaluation of Generic EBS Design Concepts and Process Models Implications  

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

Generic EBS Design Concepts and Process Models Generic EBS Design Concepts and Process Models Implications to EBS Design Optimization Evaluation of Generic EBS Design Concepts and Process Models Implications to EBS Design Optimization The assessment of generic Engineered Barrier System (EBS) concepts and design optimization to harbor various disposal configurations and waste types needs advanced approaches and methods to analyze barrier performance. The report addresses: 1) Overview of the importance of Thermal-Hydrological-Mechanical-Chemical (THMC) processes to barrier performance, and international collaborations; 2) THMC processes in clay barriers; 3) experimental studies of clay stability and clay-metal interactions at high temperatures and pressures; 4) thermodynamic modeling and database development; 5) Molecular Dynamics (MD) study of clay

270

The shallow shelf approximation as a "sliding law" in a thermomechanically coupled ice sheet model  

E-Print Network [OSTI]

The shallow shelf approximation is a better ``sliding law'' for ice sheet modeling than those sliding laws in which basal velocity is a function of driving stress. The shallow shelf approximation as formulated by \\emph{Schoof} [2006a] is well-suited to this use. Our new thermomechanically coupled sliding scheme is based on a plasticity assumption about the strength of the saturated till underlying the ice sheet in which the till yield stress is given by a Mohr-Coulomb formula using a modeled pore water pressure. Using this scheme, our prognostic whole ice sheet model has convincing ice streams. Driving stress is balanced in part by membrane stresses, the model is computable at high spatial resolution in parallel, it is stable with respect to parameter changes, and it produces surface velocities seen in actual ice streams.

Bueler, Ed

2008-01-01T23:59:59.000Z

271

Next-to-leading order QCD corrections to the top quark associated with $?$ production via model-independent flavor-changing neutral-current couplings at hadron colliders  

E-Print Network [OSTI]

We present the complete next-to-leading order (NLO) QCD corrections to the top quark associated with $\\gamma$ production induced by model-independent $tq\\gamma$ and $tqg$ flavor-changing neutral-current (FCNC) couplings at hadron colliders, respectively. We also consider the mixing effects between the $tq\\gamma$ and $tqg$ FCNC couplings for this process. Our results show that, for the $tq\\gamma$ couplings, the NLO QCD corrections can enhance the total cross sections by about 50% and 40% at the Tevatron and LHC, respectively. Including the contributions from the $tq\\gamma$, $tqg$ FCNC couplings and their mixing effects, the NLO QCD corrections can enhance the total cross sections by about 50% for the $tu\\gamma$ and $tug$ FCNC couplings, and by about the 80% for the $tc\\gamma$ and $tcg$ FCNC couplings at the LHC, respectively. Moreover, the NLO corrections reduce the dependence of the total cross section on the renormalization and factorization scale significantly. We also evaluate the NLO corrections for several important kinematic distributions.

Yue Zhang; Bo Hua Li; Chong Sheng Li; Jun Gao; Hua Xing Zhu

2011-01-27T23:59:59.000Z

272

On the connection between continental-scale land surface processes and the tropical climate in a coupled ocean-atmosphere-land system  

SciTech Connect (OSTI)

The impact of global tropical climate to perturbations in land surface processes (LSP) are evaluated using perturbations given by different LSP representations of continental-scale in a global climate model that includes atmosphere-ocean interactions. One representation is a simple land scheme, which specifies climatological albedos and soil moisture availability. The other representation is the more comprehensive Simplified Simple Biosphere Model, which allows for interactive soil moisture and vegetation biophysical processes. The results demonstrate that LSP processes such as interactive soil moisture and vegetation biophysical processes have strong impacts on the seasonal mean states and seasonal cycles of global precipitation, clouds, and surface air temperature. The impact is especially significant over the tropical Pacific. To explore the mechanisms for such impact, different LSP representations are confined to selected continental-scale regions where strong interactions of climate-vegetation biophysical processes are present. We find that the largest impact is mainly from LSP perturbations over the tropical African continent. The impact is through anomalous convective heating in tropical Africa due to changes in the surface heat fluxes, which in turn affect basinwide teleconnections in the Pacific through equatorial wave dynamics. The modifications in the equatorial Pacific climate are further enhanced by strong air-sea coupling between surface wind stress and upwelling, as well as effect of ocean memory. Our results further suggest that correct representations of land surface processes, land use change and the associated changes in the deep convection over tropical Africa are crucial to reducing the uncertainty when performing future climate projections under different climate change scenarios.

Ma, Hsi-Yen; Mechoso, C. R.; Xue, Yongkang; Xiao, Heng; Neelin, David; Ji, Xuan

2013-11-15T23:59:59.000Z

273

Development and Evaluation of a Coupled Photosynthesis-Based Gas Exchange Evapotranspiration Model (GEM) for Mesoscale Weather Forecasting Applications  

E-Print Network [OSTI]

Development and Evaluation of a Coupled Photosynthesis-Based Gas Exchange Evapotranspiration Model with a photosynthesis-based scheme and still achieve dynamically consistent results. To demonstrate this transformative potential, the authors developed and coupled a photosynthesis, gas exchange­based surface evapotranspiration

Niyogi, Dev

274

Modelling biological processes using workflow and Petri Net models  

Science Journals Connector (OSTI)

......of regulatory networks. Bioinformatics , 16 , 1120 1128. Schlenoff,C., Gruninger,M., Tissot,F., Valois,J., Lubell,J. and Lee,J. (2000) The Process Specification Language (PSL): Overview and Version 1.0 Specification. National......

Mor Peleg; Iwei Yeh; Russ B. Altman

2002-06-01T23:59:59.000Z

275

Statistical post processing of model output from the air quality model LOTOS-EUROS  

E-Print Network [OSTI]

Statistical post processing of model output from the air quality model LOTOS-EUROS Annemiek processing of model output from the air quality model LOTOS-EUROS Author: Annemiek Pijnappel Supervisor summary Air quality forecasts are produced routinely, focusing on concentrations of polluting gases

Stoffelen, Ad

276

Dispersive processes in models of regional radionuclide migration. Technical memorandum  

SciTech Connect (OSTI)

Three broad areas of concern in the development of aquifer scale transport models will be local scale diffusion and dispersion processes, regional scale dispersion processes, and numerical problems associated with the advection-dispersion equation. Local scale dispersion processes are fairly well understood and accessible to observation. These processes will generally be dominated in large scale systems by regional processes, or macro-dispersion. Macro-dispersion is primarily the result of large scale heterogeneities in aquifer properties. In addition, the effects of many modeling approximations are often included in the process. Because difficulties arise in parameterization of this large scale phenomenon, parameterization should be based on field measurements made at the same scale as the transport process of interest or else partially circumvented through the application of a probabilistic advection model. Other problems associated with numerical transport models include difficulties with conservation of mass, stability, numerical dissipation, overshoot, flexibility, and efficiency. We recommend the random-walk model formulation for Lawrence Livermore Laboratory's purposes as the most flexible, accurate and relatively efficient modeling approach that overcomes these difficulties.

Evenson, D.E.; Dettinger, M.D.

1980-05-01T23:59:59.000Z

277

HYDROGEOCHEM: A coupled model of HYDROlogic transport and GEOCHEMical equilibria in reactive multicomponent systems  

SciTech Connect (OSTI)

This report presents the development of a hydrogeochemical transport model for multicomponent systems. The model is designed for applications to proper hydrological setting, accommodation of complete suite of geochemical equilibrium processes, easy extension to deal with chemical kinetics, and least constraints of computer resources. The hydrological environment to which the model can be applied is the heterogeneous, anisotropic, saturated-unsaturated subsurface media under either transient or steady state flow conditions. The geochemical equilibrium processes included in the model are aqueous complexation, adsorption-desorption, ion exchange, precipitation-dissolution, redox, and acid-base reactions. To achieve the inclusion of the full complement of these geochemical processes, total analytical concentrations of all chemical components are chosen as the primary dependent variables in the hydrological transport equations. Attendant benefits of this choice are to make the extension of the model to deal with kinetics of adsorption-desorption, ion exchange, precipitation-dissolution, and redox relatively easy. To make the negative concentrations during the iteration between the hydrological transport and geochemical equilibrium least likely, an implicit form of transport equations are proposed. To alleviate severe constraints of computer resources in terms of central processing unit (CPU) time and CPU memory, various optional numerical schemes are incorporated in the model. The model consists of a hydrological transport module and geochemical equilibrium module. Both modules were thoroughly tested in code consistency and were found to yield plausible results. The model is verified with ten examples. 79 refs., 21 figs., 17 tabs.

Yeh, G.T.; Tripathi, V.S.

1990-11-01T23:59:59.000Z

278

Modeling two-dimensional magnetic resonance measurements in coupled pore systems  

Science Journals Connector (OSTI)

We present numerical simulations of a two-dimensional (2D) nuclear magnetic resonance process, T2-storage-T2, on a simple mixed porosity system, the micrograin consolidation (?GC) model. The results of these calculations are compared with predictions based on the analytic two-site exchange model, for which we have independently established numerical values for all the input parameters. Although there is qualitative and semiquantitative agreement between the two models, we identify specific instances where the two-site model fails to properly describe the combined effects of relaxation and diffusion. Generally, these instances occur when a gradient in magnetization within the large pores of the ?GC model is established during the initial phase of the 2D process. The two-site model assumes that the magnetization is spatially uniform within each of its subpore systems and thus cannot describe such effects.

L. M. Schwartz; D. L. Johnson; J. Mitchell; T. C. Chandrasekera; E. J. Fordham

2013-09-30T23:59:59.000Z

279

An Analytic Model for Colluding Processes Stephen M. Watt  

E-Print Network [OSTI]

An Analytic Model for Colluding Processes Stephen M. Watt University of Western Ontario London, Canada www.csd.uwo.ca/watt Abstract--We develop a quantitative framework in order to understand how

Watt, Stephen M.

280

Modeling designers' color decision processes through emotive choice mapping  

Science Journals Connector (OSTI)

Color selection support systems require a quantitative model of the color design decision-making process in order to support color selection strategies that further the specified goals of the designer without obstructing the unspecified goals. The system ...

Eric W. Cooper; Yuko Ishida; Katsuari Kamei

2005-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

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

Science Journals Connector (OSTI)

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

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

2011-03-01T23:59:59.000Z

282

Project title: Stimulation at Desert Peak and Bradys reservoirs: modeling with the coupled THM code FEHM  

Broader source: Energy.gov [DOE]

Project title: Stimulation at Desert Peak and Bradys reservoirs: modeling with the coupled THM code FEHM presentation at the April 2013 peer review meeting held in Denver, Colorado.

283

Response of a Coupled Ocean–Atmosphere Model to Increasing Atmospheric Carbon Dioxide: Sensitivity to the Rate of Increase  

Science Journals Connector (OSTI)

The influence of differing rates of increase of the atmospheric CO2 concentration on the climatic response is investigated using a coupled ocean–atmosphere model. Five transient integrations are performed each using a different constant ...

Ronald J. Stouffer; Syukuro Manabe

1999-08-01T23:59:59.000Z

284

Response of a coupled ocean-ice-atmosphere model to data assimilation in the tropical zone of the Pacific Ocean  

Science Journals Connector (OSTI)

This paper deals with numerical experiments based on the coupled ECHAM-HOPE model. The results of experiments are analyzed. The initial fields for the calculations over time periods from one month to one year ...

K. P. Belyaev; N. P. Tuchkova; U. Cubash

2010-06-01T23:59:59.000Z

285

Coupled In-Rock and In-Drift Hydrothermal Model Stuudy For Yucca Mountain  

SciTech Connect (OSTI)

A thermal-hydrologic-natural-ventilation model is configured for simulating temperature, humidity, and condensate distributions in the coupled domains of the in-drift airspace and the near-field rockmass in the proposed Yucca Mountain repository. The multi-physics problem is solved with MULTIFLUX in which a lumped-parameter computational fluid dynamics model is iterated with TOUGH2. The solution includes natural convection, conduction, and radiation for heat as well as moisture convection and diffusion for moisture transport with half waste package scale details in the drift, and mountain-scale heat and moisture transport in the porous and fractured rock-mass. The method provides fast convergence on a personal computer computational platform. Numerical examples and comparison with a TOUGH2 based, integrated model are presented.

G. Danko; J. Birkholzer; D. Bahrami

2006-12-18T23:59:59.000Z

286

Close-coupled Catalytic Two-Stage Liquefaction (CTSL{trademark}) process bench studies. Final report, [October 1, 1988--July 31, 1993  

SciTech Connect (OSTI)

This is the final report of a four year and ten month contract starting on October 1, 1988 to July 31, 1993 with the US Department of Energy to study and improve Close-Coupled Catalytic Two-Stage Direct Liquefaction of coal by producing high yields of distillate with improved quality at lower capital and production costs in comparison to existing technologies. Laboratory, Bench and PDU scale studies on sub-bituminous and bituminous coals are summarized and referenced in this volume. Details are presented in the three topical reports of this contract; CTSL Process Bench Studies and PDU Scale-Up with Sub-Bituminous Coal-DE-88818-TOP-1, CTSL Process Bench Studies with Bituminous Coal-DE-88818-TOP-2, and CTSL Process Laboratory Scale Studies, Modelling and Technical Assessment-DE-88818-TOP-3. Results are summarized on experiments and studies covering several process configurations, cleaned coals, solid separation methods, additives and catalysts both dispersed and supported. Laboratory microautoclave scale experiments, economic analysis and modelling studies are also included along with the PDU-Scale-Up of the CTSL processing of sub-bituminous Black Thunder Mine Wyoming coal. During this DOE/HRI effort, high distillate yields were maintained at higher throughput rates while quality was markedly improved using on-line hydrotreating and cleaned coals. Solid separations options of filtration and delayed coking were evaluated on a Bench-Scale with filtration successfully scaled to a PDU demonstration. Directions for future direct coal liquefaction related work are outlined herein based on the results from this and previous programs.

Comolli, A.G.; Johanson, E.S.; Karolkiewicz, W.F.; Lee, L.K.; Popper, G.A.; Stalzer, R.H.; Smith, T.O.

1993-06-01T23:59:59.000Z

287

Effects of Hydrodynamic Modelling in Fully Coupled Simulations of a Semi-submersible Wind Turbine  

Science Journals Connector (OSTI)

This work examines the dynamic response of a single semi-submersible wind turbine (SSWT) based on different hydrodynamic theories. Comparisons of platform motions and structural responses in the wind turbine are shown for simulations for a model with linear potential ?ow solution and quadratic drag and simulations with only Morison-type forces. The SSWT modelled in this study is based on WindFloat and carries the NREL 5MW wind turbine and should be considered a large volume structure. This implies that diffraction effects should be considered by using potential ?ow theory and viscous effects by Morison's equation.A new coupled simulation code was developed by linking the SIMO and RIFLEX hydrodynamic, structural, and control system computational tools, from MARINTEK, with the aerodynamic forces and wind ?eld generation capabili–ties of AeroDyn and TurbSim, from NREL. In contrast to other available simulation codes, this combination enabled the implementation of these two different hydrodynamic theories and offered the possibility of ?nite element mooring line models. Wave-only simulations were considered ?rst, in order to tune and compare potential theory versus the inertia term in Morison's equation. Some limited coupled wave-wind simulations give an indication of the extent to which hydrodynamic modelling affects the global response.The SSWT case study showed that the Morison model with forces integrated up to wave elevation gave a good representation of the motions compared to the potential ?ow model with quadratic drag forces. It also showed that mo–tions are sensitive to choice of added mass coefficients, stretching and dynamic pressure under the columns. Combined wind and wave simulations, using a non-optimized control approach, showed that pitch motions in?uence the power production and blade bending moments.

Marit I. Kvittem; Erin E. Bachynski; Torgeir Moan

2012-01-01T23:59:59.000Z

288

MODELING OF THERMALLY DRIVEN HYDROLOGICAL PROCESSES IN PARTIALLY  

E-Print Network [OSTI]

) incorporation of a full set of thermal-hydrological processes into a numerical simulator, (2) realistic AND BACKGROUND [2] The containment of spent fuel from nuclear power plants in a geological repositoryMODELING OF THERMALLY DRIVEN HYDROLOGICAL PROCESSES IN PARTIALLY SATURATED FRACTURED ROCK Y. W

Jellinek, Mark

289

PROCESS MODELING AND CONTROL The Department of Chemical Engineering  

E-Print Network [OSTI]

) · S. Ziaii ­ CO2 absorption process modeling and control/power plant energy integration (Joint research in our department #12;· Ensure safe plant operation · Meet product specifications · Optimize/Control · B. Gill ­ Virtual sensors in etch processes (Texas Instruments) · X. Jiang ­ Controller performance

Lightsey, Glenn

290

Artificial neural network modeling techniques applied to the hydrodesulfurization process  

Science Journals Connector (OSTI)

Reduction of harmful emissions in the combustion of fossil fuels imposes tighter specifications limiting the sulfur content of fuels. Hydrodesulfurization (HDS) is a key process in most petroleum refineries in which the sulfur is mostly eliminated. The ... Keywords: Hydrodesulfurization, Neural networks, Pollution, Process modeling

Enrique Arce-Medina; José I. Paz-Paredes

2009-01-01T23:59:59.000Z

291

TSPA Model Development and Sensitivity Analysis of Processes Affecting  

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

TSPA Model Development and Sensitivity Analysis of Processes TSPA Model Development and Sensitivity Analysis of Processes Affecting Performance of a Salt Repository for Disposal of Heat-Generating Nuclear Waste TSPA Model Development and Sensitivity Analysis of Processes Affecting Performance of a Salt Repository for Disposal of Heat-Generating Nuclear Waste The document describes the initial work on designing and developing requirements for a total system performance assessment (TSPA) model that can support preliminary safety assessments for a mined geologic repository for high-level waste (HLW) and spent nuclear fuel (SNF) in salt host rock at a generic site. A preliminary generic salt TSPA model for HLW/SNF disposal has been developed and tested for an isothermal repository in salt, for emplaced waste that is assumed to have no decay heat; for salt

292

The Aerosol Modeling Testbed: A community tool to objectively evaluate aerosol process modules  

SciTech Connect (OSTI)

This study describes a new modeling paradigm that significantly advances how the third activity is conducted while also fully exploiting data and findings from the first two activities. The Aerosol Modeling Testbed (AMT) is a computational framework for the atmospheric sciences community that streamlines the process of testing and evaluating aerosol process modules over a wide range of spatial and temporal scales. The AMT consists of a fully-coupled meteorology-chemistry-aerosol model, and a suite of tools to evaluate the performance of aerosol process modules via comparison with a wide range of field measurements. The philosophy of the AMT is to systematically and objectively evaluate aerosol process modules over local to regional spatial scales that are compatible with most field campaigns measurement strategies. The performance of new treatments can then be quantified and compared to existing treatments before they are incorporated into regional and global climate models. Since the AMT is a community tool, it also provides a means of enhancing collaboration and coordination among aerosol modelers.

Fast, Jerome D.; Gustafson, William I.; Chapman, Elaine G.; Easter, Richard C.; Rishel, Jeremy P.; Zaveri, Rahul A.; Grell, Georg; Barth, Mary

2011-03-02T23:59:59.000Z

293

Plastic bottle oscillator as an on-off-type oscillator: Experiments, modeling, and stability analyses of single and coupled systems  

Science Journals Connector (OSTI)

An oscillatory system called a plastic bottle oscillator is studied, in which the downflow of water and upflow of air alternate periodically in an upside-down plastic bottle containing water. It is demonstrated that a coupled two-bottle system exhibits in- and antiphase synchronization according to the nature of coupling. A simple ordinary differential equation is deduced to interpret the characteristics of a single oscillator. This model is also extended to coupled oscillators, and the model reproduces the essential features of the experimental observations.

Masahiro I. Kohira; Hiroyuki Kitahata; Nobuyuki Magome; Kenichi Yoshikawa

2012-02-03T23:59:59.000Z

294

Assessing thermal energy storage technologies of concentrating solar plants for the direct coupling with chemical processes. The case of solar-driven biomass gasification  

Science Journals Connector (OSTI)

Abstract Dynamic simulation, design improvements and control issues in solar power plants might compete with special considerations on energy storing techniques. In order to provide the stability in production of power or chemical commodities in spite of discontinuity in the source of energy, i.e., sun, overall concerns in the details of solar power plant, competition and comparison of common storing technologies should be taken into account to ensure the effectiveness and continuity of the supply. This research activity is aimed at extending the study from the power generation purpose to the solar-supplied chemical commodities production, highlighting the limitations of certain well-established thermal energy storage techniques when concentrating solar is directly coupled with chemical processes. The (intrinsically dynamic and closed-loop) simulation of solar power plants and direct thermal energy storage technologies is performed for the direct thermal energy storage technologies and, only for the case of thermocline, it is coupled with computational fluid-dynamic (CFD) studies for the proper assessment of molten salt and steam temperature trends. To investigate benefits/restrictions of the storage technologies, the solar steam generation is integrated with the gasification of biomasses for syngas production. Also, first-principles dynamic model for the biomass gasifier is provided.

Flavio Manenti; Andres R. Leon-Garzon; Zohreh Ravaghi-Ardebili; Carlo Pirola

2014-01-01T23:59:59.000Z

295

SolarStat: Modeling Photovoltaic Sources through Stochastic Markov Processes  

E-Print Network [OSTI]

SolarStat: Modeling Photovoltaic Sources through Stochastic Markov Processes Marco Miozzo target photovoltaic panels with small form factors, as those exploited by embedded communication devices the GPL license at [1]. Index Terms--Renewable Photovoltaic Sources, Stochastic Markov Modeling, Empirical

Rossi, Michele

296

Desert dust and anthropogenic aerosol interactions in the Community Climate System Model coupled-carbon-climate model  

SciTech Connect (OSTI)

Coupled-carbon-climate simulations are an essential tool for predicting the impact of human activity onto the climate and biogeochemistry. Here we incorporate prognostic desert dust and anthropogenic aerosols into the CCSM3.1 coupled carbon-climate model and explore the resulting interactions with climate and biogeochemical dynamics through a series of transient anthropogenic simulations (20th and 21st centuries) and sensitivity studies. The inclusion of prognostic aerosols into this model has a small net global cooling effect on climate but does not significantly impact the globally averaged carbon cycle; we argue that this is likely to be because the CCSM3.1 model has a small climate feedback onto the carbon cycle. We propose a mechanism for including desert dust and anthropogenic aerosols into a simple carbon-climate feedback analysis to explain the results of our and previous studies. Inclusion of aerosols has statistically significant impacts on regional climate and biogeochemistry, in particular through the effects on the ocean nitrogen cycle and primary productivity of altered iron inputs from desert dust deposition.

Mahowald, Natalie [Cornell University; Rothenberg, D. [Cornell University; Lindsay, Keith [National Center for Atmospheric Research (NCAR); Doney, Scott C. [Woods Hole Oceanographic Institution; Moore, Jefferson Keith [University of California, Irvine; Randerson, James T. [University of California, Irvine; Thornton, Peter E [ORNL; Jones, C. D. [Hadley Center, Devon, England

2011-02-01T23:59:59.000Z

297

Gaussian Process Modeling: Applications to Building Systems and Algorithmic  

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

Gaussian Process Modeling: Applications to Building Systems and Algorithmic Gaussian Process Modeling: Applications to Building Systems and Algorithmic Challenges Speaker(s): Victor M. Zavala Date: November 5, 2013 - 12:00pm - 1:00pm Location: 90-3122 Seminar Host/Point of Contact: Mary Ann Piette Michael Sohn We review applications and algorithmic challenges of Gaussian Process (GP) modeling. GP is a powerful and flexible uncertainty quantification and data analysis technique that enables the construction of complex models without the need to specify algebraic relationships between variables. This is done by working directly in the space of the kernel or covariance matrix. In addition, it derives from a Bayesian framework and, as such, it naturally provides predictive probability distributions. We describe how these features can be exploited in Measurement and Verification (M&V) tasks and

298

A Process Model for the Production of Hydrogen Using High Temperature Electrolysis  

SciTech Connect (OSTI)

High temperature electrolysis (HTE) involves the splitting of stream into hydrogen and oxygen at high temperatures. The primary advantage of HTE over conventional low temperature electrolysis is that considerably higher hydrogen production efficiencies can be achieved. Performing the electrolysis process at high temperatures results in more favorable thermodynamics for electrolysis, more efficient production of electricity, and allows direct use of process heat to generate steam. This paper presents the results of process analyses performed to evaluate the hydrogen production efficiencies of an HTE plant coupled to a 600 MWt Modular Helium Reactor (MHR) that supplies both the electricity and process heat needed to drive the process. The MHR operates with a coolant outlet temperature of 950 C. Approximately 87% of the high-temperature heat is used to generate electricity at high efficiency using a direct, Brayton-cycle power conversion system. The remaining high-temperature heat is used to generate a superheated steam / hydrogen mixture that is supplied to the electrolyzers. The analyses were performed using the HYSYS process modeling software. The model used to perform the analyses consisted of three loops; a primary high temperature helium loop, a secondary helium loop and the HTE process loop. The detailed model included realistic representations of all major components in the system, including pumps, compressors, heat exchange equipment, and the electrolysis stack. The design of the hydrogen production process loop also included a steam-sweep gas system to remove oxygen from the electrolysis stack so that it can be recovered and used for other applications. Results of the process analyses showed that hydrogen production efficiencies in the range of 45% to 50% are achievable with this system.

M. G. Mc Kellar; E. A. Harvego; M. Richards; A. Shenoy

2006-07-01T23:59:59.000Z

299

Implementation of New Process Models for Tailored Polymer Composite Structures into Processing Software Packages  

SciTech Connect (OSTI)

This report describes the work conducted under the Cooperative Research and Development Agreement (CRADA) (Nr. 260) between the Pacific Northwest National Laboratory (PNNL) and Autodesk, Inc. to develop and implement process models for injection-molded long-fiber thermoplastics (LFTs) in processing software packages. The structure of this report is organized as follows. After the Introduction Section (Section 1), Section 2 summarizes the current fiber orientation models developed for injection-molded short-fiber thermoplastics (SFTs). Section 3 provides an assessment of these models to determine their capabilities and limitations, and the developments needed for injection-molded LFTs. Section 4 then focuses on the development of a new fiber orientation model for LFTs. This model is termed the anisotropic rotary diffusion - reduced strain closure (ARD-RSC) model as it explores the concept of anisotropic rotary diffusion to capture the fiber-fiber interaction in long-fiber suspensions and uses the reduced strain closure method of Wang et al. to slow down the orientation kinetics in concentrated suspensions. In contrast to fiber orientation modeling, before this project, no standard model was developed to predict the fiber length distribution in molded fiber composites. Section 5 is therefore devoted to the development of a fiber length attrition model in the mold. Sections 6 and 7 address the implementations of the models in AMI, and the conclusions drawn from this work is presented in Section 8.

Nguyen, Ba Nghiep; Jin, Xiaoshi; Wang, Jin; Phelps, Jay; Tucker III, Charles L.; Kunc, Vlastimil; Bapanapalli, Satish K.; Smith, Mark T.

2010-02-23T23:59:59.000Z

300

Dynamic modeling of nitrogen losses in river networks unravels the coupled effects of hydrological  

E-Print Network [OSTI]

that control denitrifica- tion. Hydrological discharge regimes affect the degree of interaction of the water, with particular attention to the processes that deliver large nitrogen loads to sensitive coastal ecosystems. We measurements from a variety of US streams. These relations are used in the stream transport model

Note: This page contains sample records for the topic "modeling coupled processes" 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

Transient Response of the Hadley Centre Coupled Ocean-Atmosphere Model to Increasing Carbon Dioxide. Part III: Analysis of Global-Mean Response Using Simple Models  

Science Journals Connector (OSTI)

The roles of surface, atmospheric, and oceanic feedbacks in controlling the global-mean transient response of a coupled ocean-atmosphere general circulation model to increasing carbon dioxide are investigated. The analysis employs a four-box ...

J. M. Murphy

1995-03-01T23:59:59.000Z

302

Life cycle assessment of hydrogen production from S-I thermochemical process coupled to a high temperature gas reactor  

SciTech Connect (OSTI)

The purpose of this paper is to quantify the greenhouse gas (GHG) emissions associated to the hydrogen produced by the sulfur-iodine thermochemical process, coupled to a high temperature nuclear reactor, and to compare the results with other life cycle analysis (LCA) studies on hydrogen production technologies, both conventional and emerging. The LCA tool was used to quantify the impacts associated with climate change. The product system was defined by the following steps: (i) extraction and manufacturing of raw materials (upstream flows), (U) external energy supplied to the system, (iii) nuclear power plant, and (iv) hydrogen production plant. Particular attention was focused to those processes where there was limited information from literature about inventory data, as the TRISO fuel manufacture, and the production of iodine. The results show that the electric power, supplied to the hydrogen plant, is a sensitive parameter for GHG emissions. When the nuclear power plant supplied the electrical power, low GHG emissions were obtained. These results improve those reported by conventional hydrogen production methods, such as steam reforming. (authors)

Giraldi, M. R.; Francois, J. L.; Castro-Uriegas, D. [Departamento de Sistemas Energeticos, Facultad de Ingenieria, Universidad Nacional Autonoma de Mexico, Paseo Cuauhnahuac No. 8532, Col. Progreso, C.P. 62550, Jiutepec, Morelos (Mexico)

2012-07-01T23:59:59.000Z

303

Framework for Coupling Room Air Models to Heat Balance Model Load and Energy Calculations (RP-1222)  

E-Print Network [OSTI]

for Buildings and Thermal Systems, National Renewable Energy Laboratory, Golden, Colo., and Qingyan (Yan) Chen systems, estimating building energy use and predicting thermal comfort for buildings with buoyancy models with building energy and load calculations as an extension to the ASHRAE Toolkit for Building Load

Chen, Qingyan "Yan"

304

Improving potato drought simulations: Assessing water stress factors using a coupled model  

Science Journals Connector (OSTI)

Abstract Effective water management is important for drought sensitive crops like potato (Solanum tuberosum L.). Crop simulation models are well suited for evaluating water limited responses in order to provide management and phenotypic-trait recommendations for more efficient production practice. There is considerable variation in how water stress components are implemented with regards to simulating soil, plant, and atmospheric relationships, thereby influencing the utility of model recommendations. Four water-stress factors were developed and implemented in the potato model SPUDIM in order to assess the contribution each factor provided for improving modeling accuracy. Iterative comparisons versus experimental data consisting of six irrigation treatments were used. Factors included F1, shifts in carbon allocation among shoot and root organs based on soil moisture availability, F2, coupled response of leaf water potential on leaf expansion, F3, and on stomatal conductance, and F4, increased tuber sink strength. F2 and F3 accounted for up to 88% of the improvement in root mean square error for total biomass. However, F1 and F4 were necessary to accurately simulate yield. F4 was also required to reproduce trends of increasing water-use efficiency and harvest index with declines in water availability. When the full 4-factor model was considered, simulated responses for total, leaf, stem, and tuber dry weights were within 11% of observed values. Daily comparisons for whole plant net photosynthesis and evapotranspiration indicated F3 was required to accurately simulate water use, but was too sensitive to very low leaf water potentials. The calibration coefficients used in the model remained stable over all six irrigation treatments, suggesting the full model can be utilized to evaluate water management strategies for potato.

David H. Fleisher; A. Dathe; D.J. Timlin; V.R. Reddy

2015-01-01T23:59:59.000Z

305

Composite dark energy: cosmon models with running cosmological term and gravitational coupling  

E-Print Network [OSTI]

In the recent literature on dark energy (DE) model building we have learnt that cosmologies with variable cosmological parameters can mimic more traditional DE pictures exclusively based on scalar fields (e.g. quintessence and phantom). In a previous work we have illustrated this situation within the context of a renormalization group running cosmological term, Lambda. Here we analyze the possibility that both the cosmological term and the gravitational coupling, G, are running parameters within a more general framework (a variant of the so-called ``LXCDM models'') in which the DE fluid can be a mixture of a running Lambda and another dynamical entity X (the ``cosmon'') which may behave quintessence-like or phantom-like. We compute the effective EOS parameter, w, of this composite fluid and show that the LXCDM can mimic to a large extent the standard LCDM model while retaining features hinting at its potential composite nature (such as the smooth crossing of the cosmological constant boundary w=-1). We further argue that the LXCDM models can cure the cosmological coincidence problem. All in all we suggest that future experimental studies on precision cosmology should take seriously the possibility that the DE fluid can be a composite medium whose dynamical features are partially caused and renormalized by the quantum running of the cosmological parameters.

Javier Grande; Joan Sola; Hrvoje Stefancic

2006-12-16T23:59:59.000Z

306

Kaon condensation and composition of neutron star matter in modified quark-meson coupling model  

E-Print Network [OSTI]

We use the modified quark-meson coupling (MQMC) model to study the composition profile of neutron star matter and compare the results with those calculated by quantum hadrodynamics (QHD). Both MQMC and QHD model parameters are adjusted to produce exactly the same saturation properties so that we can investigate the model dependences of the matter composition at high densities. We consider the possibility of deep kaon optical potential and find that the composition of matter is very sensitive to the interaction strength of kaons with matter. The onset densities of the kaon condensation are studied in detail by varying the kaon optical potentials. We find that the MQMC model produces the kaon condensation at lower densities than QHD. The presence of kaon condensation changes drastically the population of octet baryons and leptons. Once the kaon condensation takes place, the population of kaons builds up very quickly, and kaons become the dominant component of the matter. We find that the $\\omega$-meson plays an important role in increasing the kaon population and suppressing the hyperon population.

C. Y. Ryu; C. H. Hyun; S. W. Hong; B. T. Kim

2007-03-29T23:59:59.000Z

307

Modeling the Dynamical Coupling of Solar Convection with the Radiative Interior  

Science Journals Connector (OSTI)

The global dynamics of a rotating star like the Sun involves the coupling of a highly turbulent convective envelope overlying a seemingly benign radiative interior. We use the anelastic spherical harmonic code to develop a new class of three-dimensional models that nonlinearly couple the convective envelope to a deep stable radiative interior. The numerical simulation assumes a realistic solar stratification from r = 0.07 up to 0.97R (with R the solar radius), thus encompassing part of the nuclear core up through most of the convection zone. We find that a tachocline naturally establishes itself between the differentially rotating convective envelope and the solid body rotation of the interior, with a slow spreading that is here diffusively controlled. The rapid angular momentum redistribution in the convective envelope leads to a fast equator and slow poles, with a conical differential rotation achieved at mid-latitudes, much as has been deduced by helioseismology. The convective motions are able to overshoot downward about 0.04R into the radiative interior. However, the convective meridional circulation there is confined to a smaller penetration depth and is directed mostly equatorward at the base of the convection zone. Thermal wind balance is established in the lower convection zone and tachocline but departures are evident in the upper convection zone. Internal gravity waves are excited by the convective overshooting, yielding a complex wave field throughout the radiative interior.

Allan Sacha Brun; Mark S. Miesch; Juri Toomre

2011-01-01T23:59:59.000Z

308

Transition Prediction for Scramjet Intakes Using the \\gamma-Re_\\theta_t Model Coupled to Two Turbulence Models  

E-Print Network [OSTI]

Due to the thick boundary layers in hypersonic flows, the state of the boundary layer significantly influences the whole flow field as well as surface heat loads. Hence, for engineering applications the efficient numerical prediction of laminar-to-turbulent transition is a challenging and important task. Within the framework of the Reynolds averaged Navier-Stokes equations, Langtry/Menter [1] proposed the -Re?t transition model using two transport equations for the intermittency and Re?t combined with the Shear Stress Transport turbulence model (SST) [2]. The transition model contains two empirical correlations for onset and length of transition. Langtry/Menter [1] designed and validated the correlations for the subsonic and transonic flow regime. For our applications in the hypersonic flow regime, the development of a new set of correlations proved necessary, even when using the same SST turbulence model [3]. Within this paper, we propose a next step and couple the transition model with the SSG/LRR-! Reynold...

Frauholz, Sarah; Müller, Siegfried; Behr, Marek

2014-01-01T23:59:59.000Z

309

Modeling and co-simulation of a parabolic trough solar plant for industrial process heat  

Science Journals Connector (OSTI)

In the present paper a tri-dimensional non-linear dynamic thermohydraulic model of a parabolic trough collector was developed in the high-level acausal object-oriented language Modelica and coupled to a solar industrial process heat plant modeled in TRNSYS. The integration is performed in an innovative co-simulation environment based on the TLK interconnect software connector middleware. A discrete Monte Carlo ray-tracing model was developed in SolTrace to compute the solar radiation heterogeneous local concentration ratio in the parabolic trough collector absorber outer surface. The obtained results show that the efficiency predicted by the model agrees well with experimental data with a root mean square error of 1.2%. The dynamic performance was validated with experimental data from the Acurex solar field, located at the Plataforma Solar de Almeria, South-East Spain, and presents a good agreement. An optimization of the IST collector mass flow rate was performed based on the minimization of an energy loss cost function showing an optimal mass flow rate of 0.22 kg/s m2. A parametric analysis showed the influence on collector efficiency of several design properties, such as the absorber emittance and absorptance. Different parabolic trough solar field model structures were compared showing that, from a thermal point of view, the one-dimensional model performs close to the bi-dimensional. Co-simulations conducted on a reference industrial process heat scenario on a South European climate show an annual solar fraction of 67% for a solar plant consisting on a solar field of 1000 m2, with thermal energy storage, coupled to a continuous industrial thermal demand of 100 kW.

R. Silva; M. Pérez; A. Fernández-Garcia

2013-01-01T23:59:59.000Z

310

From conceptual process models to running systems: A holistic approach for the configuration of enterprise system processes  

Science Journals Connector (OSTI)

This paper proposes a method which aims at increasing the efficiency of enterprise system implementations. First, we argue that existing process modeling languages that feature different degrees of abstraction for different user groups exist and are ... Keywords: Business Process Modeling, Information Modeling Concepts, Model configuration, Reference modeling, System configuration

Alexander Dreiling; Michael Rosemann; Wil M. P. van der Aalst; Wasim Sadiq

2008-05-01T23:59:59.000Z

311

ASPEN modeling of the Tri-State indirect liquefaction process  

SciTech Connect (OSTI)

The ASPEN process simulator has been used to model an indirect liquefaction flowsheet patterned after that of the Tri-State project. This flowsheet uses Lurgi moving-bed gasification with synthesis gas conversion to methanol followed by further processing to gasoline using the Mobil MTG process. Models developed in this study include the following: Lurgi gasifier, Texaco gasifier, synthesis gas cooling, Rectisol, methanol synthesis, methanol-to-gasoline, CO-shift, methanation, and naphtha hydrotreating. These models have been successfully developed in modular form so that they can be used to simulate a number of different flowsheets or process alternatives. Simulations of the Tri-State flowsheet have been made using two different coal feed rates and two types of feed coal. The overall simulation model was adjusted to match the Tri-State flowsheet values for methanol, LPG, isobutane, and gasoline. As a result of this adjustment, the MTG reactor yield structure necessary to match the flowsheet product rates was determined. The models were exercised at different flow rates and were unaffected by such changes, demonstrating their range of operability. The use of Illinois No. 6 coal, with its lower ash content, resulted in slightly higher production rates for each of the products as compared to use of the Kentucky coal.

Begovich, J.M.; Clinton, J.H.; Johnson, P.J.; Barker, R.E.

1983-01-01T23:59:59.000Z

312

Dissociative electron attachment to the H2O molecule II: nucleardynamics on coupled electronic surfaces within the local complexpotential model  

SciTech Connect (OSTI)

We report the results of a first-principles study of dissociative electron attachment (DEA) to H{sub 2}O. The cross sections were obtained from nuclear dynamics calculations carried out in full dimensionality within the local complex potential model by using the multi-configuration time-dependent Hartree method. The calculations employ our previously obtained global, complex-valued, potential energy surfaces for the three ({sup 2}B{sub 1}, {sup 2}A{sub 1}, and {sup 2}B{sub 2}) electronic Feshbach resonances involved in this process. These three metastable states of H{sub 2}O{sup -} undergo several degeneracies, and we incorporate both the Renner-Teller coupling between the {sup 2}B{sub 1} and {sup 2}A{sub 1} states, as well as the conical intersection between the {sup 2}A{sub 1} and {sup 2}B{sub 2} states, into our treatment. The nuclear dynamics are inherently multi-dimensional and involve branching between different final product arrangements as well as extensive excitation of the diatomic fragment. Our results successfully mirror the qualitative features of the major fragment channels observed, but are less successful in reproducing the available results for some of the minor channels. We comment on the applicability of the local complex potential model to such a complicated resonant system.

Haxton, Daniel J.; Rescigno, Thomas N.; McCurdy, C. William

2006-12-21T23:59:59.000Z

313

Strong-coupling expansions for the topologically inhomogeneous Bose-Hubbard model  

SciTech Connect (OSTI)

We consider a Bose-Hubbard model with an arbitrary hopping term and provide the boundary of the insulating phase thereof in terms of third-order strong coupling perturbative expansions for the ground state energy. In the general case two previously unreported terms occur, arising from triangular loops and hopping inhomogeneities, respectively. Quite interestingly the latter involves the entire spectrum of the hopping matrix rather than its maximal eigenpair, like the remaining perturbative terms. We also show that hopping inhomogeneities produce a first order correction in the local density of bosons. Our results apply to ultracold bosons trapped in confining potentials with arbitrary topology, including the realistic case of optical superlattices with uneven hopping amplitudes. Significant examples are provided. Furthermore, our results can be extended to magnetically tuned transitions in Josephson junction arrays.

Buonsante, P.; Penna, V.; Vezzani, A. [Dipartimento di Fisica, Politecnico di Torino and INFM, Corso Duca degli Abruzzi 24, I-10129 Torino (Italy); Dipartimento di Fisica, Universita degli Studi di Parma and INFM, Parco Area delle Scienze 7/a, I-43100 Parma (Italy)

2004-11-01T23:59:59.000Z

314

Coupled fluid flow and geomechanical deformation modeling Susan E. Minkoff a,*, C. Mike Stoneb,1  

E-Print Network [OSTI]

in the coupled code despite dynamically changing reservoir parameters via a modification to the Newton system plastic constitutive relationships available in the coupled code. The results mimic behavior which and Engineering 38 (2003) 37­56 #12;observed in a real field but difficult to capture with a fully coupled

Minkoff, Susan E.

315

Artificial neural network application for modeling the rail rolling process  

Science Journals Connector (OSTI)

Abstract Rail rolling process is one of the most complicated hot rolling processes. Evaluating the effects of parametric values on this complex process is only possible through modeling. In this study, the production parameters of different types of rails in the rail rolling processes were modeled with an artificial neural network (ANN), and it was aimed to obtain optimum parameter values for a different type of rail. For this purpose, the data from the Rail and Profile Rolling Mill in Kardemir Iron & Steel Works Co. (Karabük, Turkey) were used. BD1, BD2, and Tandem are three main parts of the rolling mill, and in order to obtain the force values of the 49 kg/m rail in each pass for the BD1 and BD2 sections, the force and torque values for the Tandem section, parameter values of 60, 54, 46, and 33 kg/m type rails were used. Comparing the results obtained from the ANN model and the actual field data demonstrated that force and torque values were obtained with acceptable error rates. The results of the present study demonstrated that ANN is an effective and reliable method to acquire data required for producing a new rail, and concerning the rail production process, it provides a productive way for accurate and fast decision making.

Hüseyin Alt?nkaya; ?lhami M. Orak; ?smail Esen

2014-01-01T23:59:59.000Z

316

Process modeling for the Integrated Thermal Treatment System (ITTS) study  

SciTech Connect (OSTI)

This report describes the process modeling done in support of the integrated thermal treatment system (ITTS) study, Phases 1 and 2. ITTS consists of an integrated systems engineering approach for uniform comparison of widely varying thermal treatment technologies proposed for treatment of the contact-handled mixed low-level wastes (MLLW) currently stored in the U.S. Department of Energy complex. In the overall study, 19 systems were evaluated. Preconceptual designs were developed that included all of the various subsystems necessary for a complete installation, from waste receiving through to primary and secondary stabilization and disposal of the processed wastes. Each system included the necessary auxiliary treatment subsystems so that all of the waste categories in the complex were fully processed. The objective of the modeling task was to perform mass and energy balances of the major material components in each system. Modeling of trace materials, such as pollutants and radioactive isotopes, were beyond the present scope. The modeling of the main and secondary thermal treatment, air pollution control, and metal melting subsystems was done using the ASPEN PLUS process simulation code, Version 9.1-3. These results were combined with calculations for the remainder of the subsystems to achieve the final results, which included offgas volumes, and mass and volume waste reduction ratios.

Liebelt, K.H.; Brown, B.W.; Quapp, W.J.

1995-09-01T23:59:59.000Z

317

A NONGAUSSIAN ORNSTEINUHLENBECK PROCESS FOR ELECTRICITY SPOT PRICE MODELING AND  

E-Print Network [OSTI]

A NON­GAUSSIAN ORNSTEIN­UHLENBECK PROCESS FOR ELECTRICITY SPOT PRICE MODELING AND DERIVATIVES for analytical pricing of electricity forward and futures contracts. Electricity forward and futures contracts to capture the observed dynamics of electricity spot prices. We also discuss the pricing of European call

Kallsen, Jan

318

Magma to Microbe: Modeling Hydrothermal Processes at Ocean Spreading Centers  

E-Print Network [OSTI]

215 Magma to Microbe: Modeling Hydrothermal Processes at Ocean Spreading Centers Geophysical is very limited. Low-temperature diffuse vent fluids, ubiquitous at hydrothermal systems, provide one microorganisms from diffuse hydrothermal vent fluids and the subseafloor at basalt-hosted mid-ocean ridges

Holden, James F.

319

Queuing Models of Airport Departure Processes for Emissions Reduction  

E-Print Network [OSTI]

is validated through a comparison of its predictions with observed data at Boston's Logan International AirportQueuing Models of Airport Departure Processes for Emissions Reduction Ioannis Simaiakis burn and emissions at airports. This paper investigates the possibility of reducing fuel burn

Gummadi, Ramakrishna

320

Dynamic Modeling and Recipe Optimization of Polyether Polyol Processes  

E-Print Network [OSTI]

Dynamic Modeling and Recipe Optimization of Polyether Polyol Processes Fall 2012 EWO Meeting Yisu Monomer Reactor Basic procedures Starters are first mixed with catalyst in the liquid phase Alkylene oxides in the liquid phase are fed in controlled rates The reactor temperature is controlled by the heat

Grossmann, Ignacio E.

Note: This page contains sample records for the topic "modeling coupled processes" 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

Adoption Process for VoIP: The UTAUT Model  

Science Journals Connector (OSTI)

This study tests the appropriateness of the Unified Theory of Acceptance and Use of Technology UTAUT model in the context of end user consumption by means of an online survey with four hundred and seventy five respondents 24% response rate. The study ... Keywords: Adoption Process, Consumer Behavior, New Technology, Unified Theory of Acceptance and Use of Technology, Voice over Internet Protocol VoIP

Eduardo Esteva-Armida; Alberto Rubio-Sanchez

2012-10-01T23:59:59.000Z

322

PASI 2011: Process Modeling and Optimization for Energy and Sustainability Mineral Process Design for  

E-Print Network [OSTI]

PASI 2011 PASI 2011: Process Modeling and Optimization for Energy and Sustainability Mineral, high population growth and urbanization, both key metals consumption and GDP are expected to grow the environmental impact, both in per tonne of product and on total amount of emissions and reduction. #12

Grossmann, Ignacio E.

323

World Climate Research Programme (WCRP) Coupled Model Intercomparison Project phase 3 (CMIP3): Multi-Model Dataset Archive at PCMDI (Program for Climate Model Diagnosis and Intercomparison)  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

In response to a proposed activity of the WCRP's Working Group on Coupled Modelling (WGCM),PCMDI volunteered to collect model output contributed by leading modeling centers around the world. Climate model output from simulations of the past, present and future climate was collected by PCMDI mostly during the years 2005 and 2006, and this archived data constitutes phase 3 of the Coupled Model Intercomparison Project (CMIP3). In part, the WGCM organized this activity to enable those outside the major modeling centers to perform research of relevance to climate scientists preparing the Fourth Asssessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC). The IPCC was established by the World Meteorological Organization and the United Nations Environmental Program to assess scientific information on climate change. The IPCC publishes reports that summarize the state of the science. This unprecedented collection of recent model output is officially known as the WCRP CMIP3 multi-model dataset. It is meant to serve IPCC's Working Group 1, which focuses on the physical climate system - atmosphere, land surface, ocean and sea ice - and the choice of variables archived at the PCMDI reflects this focus. A more comprehensive set of output for a given model may be available from the modeling center that produced it. As of November 2007, over 35 terabytes of data were in the archive and over 303 terabytes of data had been downloaded among the more than 1200 registered users. Over 250 journal articles, based at least in part on the dataset, have been published or have been accepted for peer-reviewed publication. Countries from which models have been gathered include Australia, Canada, China, France, Germany and Korea, Italy, Japan, Norway, Russia, Great Britain and the United States. Models, variables, and documentation are collected and stored. Check http://www-pcmdi.llnl.gov/ipcc/data_status_tables.htm to see at a glance the output that is available. (Description taken from http://www-pcmdi.llnl.gov/ipcc/about_ipcc.php)

324

Particle Tracking Model and Abstraction of Transport Processes  

SciTech Connect (OSTI)

The purpose of this report is to document the abstraction model being used in total system performance assessment (TSPA) model calculations for radionuclide transport in the unsaturated zone (UZ). The UZ transport abstraction model uses the particle-tracking method that is incorporated into the finite element heat and mass model (FEHM) computer code (Zyvoloski et al. 1997 [DIRS 100615]) to simulate radionuclide transport in the UZ. This report outlines the assumptions, design, and testing of a model for calculating radionuclide transport in the UZ at Yucca Mountain. In addition, methods for determining and inputting transport parameters are outlined for use in the TSPA for license application (LA) analyses. Process-level transport model calculations are documented in another report for the UZ (BSC 2004 [DIRS 164500]). Three-dimensional, dual-permeability flow fields generated to characterize UZ flow (documented by BSC 2004 [DIRS 169861]; DTN: LB03023DSSCP9I.001 [DIRS 163044]) are converted to make them compatible with the FEHM code for use in this abstraction model. This report establishes the numerical method and demonstrates the use of the model that is intended to represent UZ transport in the TSPA-LA. Capability of the UZ barrier for retarding the transport is demonstrated in this report, and by the underlying process model (BSC 2004 [DIRS 164500]). The technical scope, content, and management of this report are described in the planning document ''Technical Work Plan for: Unsaturated Zone Transport Model Report Integration'' (BSC 2004 [DIRS 171282]). Deviations from the technical work plan (TWP) are noted within the text of this report, as appropriate. The latest version of this document is being prepared principally to correct parameter values found to be in error due to transcription errors, changes in source data that were not captured in the report, calculation errors, and errors in interpretation of source data.

B. Robinson

2004-10-21T23:59:59.000Z

325

CHEOPS: A tool-integration platform for chemical process modelling and simulation  

Science Journals Connector (OSTI)

A large number of modelling tools exist for the construction and solution of mathematical models of chemical processes. Each (chemical) process modelling tool provides its own model ... This paper presents a conc...

G. Schopfer; A. Yang; L. von Wedel…

2004-08-01T23:59:59.000Z

326

Development and Application of Advanced Models for Steam Hydrogasification: Process Design and Economic Evaluation  

E-Print Network [OSTI]

design, modeling and process economic analysis are employedper day. Like BTL process, economic analysis has shown thatused as major input for process economic analysis in the

Lu, Xiaoming

2012-01-01T23:59:59.000Z

327

An evaluation of Substitute natural gas production from different coal gasification processes based on modeling  

Science Journals Connector (OSTI)

Coal and lignite will play a significant role in the future energy production. However, the technical options for the reduction of CO2 emissions will define the extent of their share in the future energy mix. The production of synthetic or substitute natural gas (SNG) from solid fossil fuels seems to be a very attractive process: coal and lignite can be upgraded into a methane rich gas which can be transported and further used in high efficient power systems coupled with CO2 sequestration technologies. The aim of this paper is to present a modeling analysis comparison between substitute natural gas production from coal by means of allothermal steam gasification and autothermal oxygen gasification. In order to produce SNG from syngas several unit operations are required such as syngas cooling, cleaning, potential compression and, of course, methanation reactors. Finally the gas which is produced has to be conditioned i.e. removal of unwanted species, such as CO2 etc. The heat recovered from the overall process is utilized by a steam cycle, producing power. These processes were modeled with the computer software IPSEpro™. An energetic and exergetic analysis of the coal to SNG processes have been realized and compared.

S. Karellas; K.D. Panopoulos; G. Panousis; A. Rigas; J. Karl; E. Kakaras

2012-01-01T23:59:59.000Z

328

Three-dimensional modelling and geothermal process simulation  

SciTech Connect (OSTI)

The subsurface geological model or 3-D GIS is constructed from three kinds of objects, which are a lithotope (in boundary representation), a number of fault systems, and volumetric textures (vector fields). The chief task of the model is to yield an estimate of the conductance tensors (fluid permeability and thermal conductivity) throughout an array of voxels. This is input as material properties to a FEHM numerical physical process model. The main task of the FEHM process model is to distinguish regions of convective from regions of conductive heat flow, and to estimate the fluid phase, pressure and flow paths. The temperature, geochemical, and seismic data provide the physical constraints on the process. The conductance tensors in the Franciscan Complex are to be derived by the addition of two components. The isotropic component is a stochastic spatial variable due to disruption of lithologies in melange. The deviatoric component is deterministic, due to smoothness and continuity in the textural vector fields. This decomposition probably also applies to the engineering hydrogeological properties of shallow terrestrial fluvial systems. However there are differences in quantity. The isotropic component is much more variable in the Franciscan, to the point where volumetric averages are misleading, and it may be necessary to select that component from several, discrete possible states. The deviatoric component is interpolated using a textural vector field. The Franciscan field is much more complicated, and contains internal singularities. 27 refs., 10 figs.

Burns, K.L.

1990-01-01T23:59:59.000Z

329

Transient Responses of a Coupled Ocean–Atmosphere Model to Gradual Changes of Atmospheric CO2. Part I. Annual Mean Response  

Science Journals Connector (OSTI)

This study investigates the response of a climate model to a gradual increase or decrease of atmospheric carbon dioxide. The model is a general circulation model of the coupled atmosphere-ocean-land surface system with global geography and ...

S. Manabe; R. J. Stouffer; M. J. Spelman; K. Bryan

1991-08-01T23:59:59.000Z

330

Large scale molecular dynamics modeling of materials fabrication processes  

SciTech Connect (OSTI)

An atomistic molecular dynamics model of materials fabrication processes is presented. Several material removal processes are shown to be within the domain of this simulation method. Results are presented for orthogonal cutting of copper and silicon and for crack propagation in silica glass. Both copper and silicon show ductile behavior, but the atomistic mechanisms that allow this behavior are significantly different in the two cases. The copper chip remains crystalline while the silicon chip transforms into an amorphous state. The critical stress for crack propagation in silica glass was found to be in reasonable agreement with experiment and a novel stick-slip phenomenon was observed.

Belak, J.; Glosli, J.N.; Boercker, D.B.; Stowers, I.F.

1994-02-01T23:59:59.000Z

331

From material flow analysis to material flow management Part I: social sciences modeling approaches coupled to MFA  

Science Journals Connector (OSTI)

This paper presents social sciences modeling approaches (SSMA) that have been coupled to material flow analyses in order to support management of material flows. The presented literature review revealed that the large share of these approaches stem from economics, as these models have similar data and modeling structure than the material flow models. The discussed modeling approaches support a better system understanding and allow for estimating the potential effects of economic policies on material flows. However, it has been shown that these approaches lack important aspects of human decision-making and, thus, the designed economic measures might not always lead to the expected improvements of the material system.

Claudia R. Binder

2007-01-01T23:59:59.000Z

332

Low density instabilities in asymmetric nuclear matter within the quark-meson coupling (QMC) model with the {delta} meson  

SciTech Connect (OSTI)

In the present work we include the isovector-scalar {delta} meson in the quark-meson coupling (QMC) model and study the properties of asymmetric nuclear within QMC without and with the {delta} meson. Recent constraints set by isospin diffusion on the slope parameter of the nuclear symmetry energy at saturation density are used to adjust the model parameters. The thermodynamical spinodal surfaces are obtained and the instability region at subsaturation densities within QMC and QMC{delta} models are compared with mean-field relativistic models. The distillation effect in the QMC model is discussed.

Santos, Alexandre M.; Providencia, Constanca; Panda, Prafulla K. [Centro de Fisica Computacional, Department of Physics, University of Coimbra, P-3004-516 Coimbra (Portugal); Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700 032, India and Centro de Fisica Computacional, Department of Physics, University of Coimbra, P-3004-516 Coimbra (Portugal)

2009-04-15T23:59:59.000Z

333

Appendix 3-1-Reflections on the data collection and modeling process In this document I briefly discuss the process used for data gathering, model building,  

E-Print Network [OSTI]

discuss the process used for data gathering, model building, and model analysis that I employed. Therefore I leave the comprehensive description of the qualitative research process and model building generation - July 2004: building a qualitative model - August 2004: Building a detailed simulation model

Rahmandad, Hazhir

334

Abstract -This paper presents a methodology and a tool for the coupled magnetic-structural with semi-analytical models. For this  

E-Print Network [OSTI]

Abstract - This paper presents a methodology and a tool for the coupled magnetic-structural with semi-analytical models. For this coupling, the magnetic model is available; we developed the structural MODEL Magnetic fields radiated by permanent magnets and conductors are computed through Coulombian

Boyer, Edmond

335

OASIS4: A Coupling Software for Next Generation Earth System Modelling Ren Redler (1), Sophie Valcke (2) and Hubert Ritzdorf (3)  

E-Print Network [OSTI]

OASIS4: A Coupling Software for Next Generation Earth System Modelling René Redler (1), Sophie system modelling, Geosci. Model. Dev., 3, 87 ­ 104 Link ­ https://oasistrac.cerfacs.fr Financial support ­ R. Redler, S. Valcke and H. Ritzdorf, 2010: OASIS4 ­ a coupling software for next generation earth

336

Cloud shading retrieval and assimilation in a satellite-model coupled mesoscale analysis system  

SciTech Connect (OSTI)

A retrieval-assimilation method has been developed as a quantitative means to exploit the information in satellite imagery regarding shading of the ground by clouds, as applied to mesoscale weather analysis. Cloud radiative parameters are retrieved from satellite visible image data and used, along with parameters computed by a numerical model, to control the model's computation of downward radiative fluxes at the ground. These fluxes influence the analysis of ground surface temperatures under clouds. The method is part of a satellite-model coupled four-dimensional analysis system that merges information from visible image data in cloudy areas with infrared sounder data in clear areas, where retrievals of surface temperatures and water vapor concentrations are assimilated. The substantial impact of shading on boundary-layer development and mesoscale circulations was demonstrated in simulations, and the value of assimilating shading retrievals was demonstrated with a case study and with a simulated analysis that included the effects of several potential sources of error. The case study was performed in the northwestern Texas area, where convective cloud development was influenced by the shading effects of a persistent region of stratiform cloud cover. Analyses that included shading retrieval assimilation had consistently smaller shelter-height temperature errors than analyses without shading retrievals. When clear-area surface temperature retrievals from sounder data were analyzed along with cloudy-area shading retrievals, the contrast in heating between the shaded and clear parts of the domain led to large variations in analyzed boundary-layer depths and had a modest impact on analyzed wind flow. The analyzed locations of upward vertical motion corresponded roughly to areas of convective cloud development observed in satellite imagery. 29 refs., 17 figs., 2 tabs.

Lipton, A.E. (Phillips Lab., Hanscom AFB, MA (United States))

1993-11-01T23:59:59.000Z

337

Evaluation and comparison of models and modelling tools simulating nitrogen processes in treatment wetlands  

Science Journals Connector (OSTI)

In this paper, two ecological models of nitrogen processes in treatment wetlands have been evaluated and compared. These models were implemented, simulated, and visualized using the Modelica modelling and simulation language [P. Fritzson, Principles of Object-Oriented Modelling and Simulation with Modelica 2.1 (Wiley-IEEE Press, USA, 2004).] and an associated tool. The differences and similarities between the MathModelica Model Editor and three other ecological modelling tools have also been evaluated. The results show that the models can well be modelled and simulated in the MathModelica Model Editor, and that nitrogen decrease in a constructed treatment wetland should be described and simulated using the Nitrification/Denitrification model as this model has the highest overall quality score and provides a more variable environment.

Stina Edelfeldt; Peter Fritzson

2008-01-01T23:59:59.000Z

338

A van der Pol coupled-oscillator model as a basis for developing a system for suppressing MHD instabilities in a tokamak  

SciTech Connect (OSTI)

The main parameters of tokamak discharges are known to be limited by large-scale MHD instabilities. Sometimes, the instabilities lead to a rapid (on time scales of tens of microseconds) disruption of the discharge current and to the release of all the energy stored in the plasma column at the discharge chamber wall. This process, which is called the disruptive instability, may have irreversible catastrophic consequences for the operation of a fusion reactor. In the present paper, a study is made of the dynamics of self-oscillations in systems of two and six van der Pol coupled oscillators. A van der Pol coupled-oscillator model is used to develop a multivariable feedback controller based on the combined principle of compensating for internal cross feedbacks within the object and introducing damping feedbacks in each control channel. By using mathematical simulation methods, it is shown that the controller designed guarantees the suppression of self-oscillations in a system of van der Pol oscillators over a fairly broad range of parameters of the object under control (and thereby provides the structural stability of the object). The nonlinear control system model makes it possible to suppress coupled MHD perturbations developing in a tokamak plasma.

Semenov, I. B. [Russian Research Centre Kurchatov Institute, Nuclear Fusion Institute (Russian Federation); Mitrishkin, Yu. V. [Russian Academy of Sciences, Institute of Control Sciences (Russian Federation); Subbotin, A. A. [Russian Research Centre Kurchatov Institute, Nuclear Fusion Institute (Russian Federation); Vertinskii, A. G. [Moscow Institute of Physics and Technology (Russian Federation); Marusov, N. L. [Russian Research Centre Kurchatov Institute, Nuclear Fusion Institute (Russian Federation); Sushin, I. S. [Moscow Institute of Physics and Technology (Russian Federation)

2006-02-15T23:59:59.000Z

339

Modeling of a Signal Processing System for Aircraft Air Data  

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

Modeling of a Signal Processing System for Aircraft Air Data Modeling of a Signal Processing System for Aircraft Air Data Instrumentation Speaker(s): Thomas John Rohloff Date: September 21, 1998 - 12:00pm Location: 90-3148 Seminar Host/Point of Contact: Joan M. Daisey The velocity, attitude and altitude of flight vehicles have typically been measured with booms that extend from the vehicle surface out into the flow field. However, this arrangement was found to be unacceptable for certain flight applications. Instrumentation was therefore developed by other researchers to measure the flight parameters using an array of pressure measurements located on the surface of the vehicle. The relationship between these pressure measurements and the air data is a complex non-linear function that is not easily described with simple aerodynamic

340

A Process Model of Applicant Faking on Overt Integrity Tests  

E-Print Network [OSTI]

of empirically tested models or appropriate theoretical structures to explain the process (Griffith & McDaniel, 2006; Murphy, 2000). Moreover, there seems to be a limited understanding of possible outcomes associated with applicant faking..., Barrett, & Hogan, 2007; McFarland & Ryan, 2006; Morgeson et al., 2007). According to recent studies, approximately 30-50% of job applicants consciously try to elevate their scores (Donovan, Dwight, & Hurtz, 2003; Griffith et al., 2007)1. Faking...

Yu, Janie

2010-01-14T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

Predictive Model for Environmental Assessment in Additive Manufacturing Process  

Science Journals Connector (OSTI)

Abstract Additive Manufacturing is an innovative way to produce parts. However its environmental impact is unknown. To ensure the development of additive manufacturing processes it seems important to develop the concept of DFSAM (Design for Sustainable Additive Manufacturing). In fact, one of the objectives of environmental sustainable manufacturing is to minimize the whole flux consumption (electricity, material and fluids) during manufacturing step. To achieve this goal, it is interesting to get a predictive model of consumptions, integrated in the design step, allowing to evaluate the product's environmental impact during the manufacturing step. This paper presents a new methodology for electric, fluids and raw material consumptions assessment for additive manufacturing processes, in particular for a direct metal deposition process. The methodology will help engineers to design parts optimized for additive manufacturing with an environmental point of view.

Florent Le Bourhis; Olivier Kerbrat; Lucas Dembinski; Jean-Yves Hascoet; Pascal Mognol

2014-01-01T23:59:59.000Z

342

Carbon sequestration by patch fertilization: A comprehensive assessment using coupled physical-ecological-biogeochemical models  

SciTech Connect (OSTI)

This final report summarizes research undertaken collaboratively between Princeton University, the NOAA Geophysical Fluid Dynamics Laboratory on the Princeton University campus, the State University of New York at Stony Brook, and the University of California, Los Angeles between September 1, 2000, and November 30, 2006, to do fundamental research on ocean iron fertilization as a means to enhance the net oceanic uptake of CO2 from the atmosphere. The approach we proposed was to develop and apply a suite of coupled physical-ecological-biogeochemical models in order to (i) determine to what extent enhanced carbon fixation from iron fertilization will lead to an increase in the oceanic uptake of atmospheric CO2 and how long this carbon will remain sequestered (efficiency), and (ii) examine the changes in ocean ecology and natural biogeochemical cycles resulting from iron fertilization (consequences). The award was funded in two separate three-year installments: • September 1, 2000 to November 30, 2003, for a project entitled “Ocean carbon sequestration by fertilization: An integrated biogeochemical assessment.” A final report was submitted for this at the end of 2003 and is included here as Appendix 1. • December 1, 2003 to November 30, 2006, for a follow-on project under the same grant number entitled “Carbon sequestration by patch fertilization: A comprehensive assessment using coupled physical-ecological-biogeochemical models.” This report focuses primarily on the progress we made during the second period of funding subsequent to the work reported on in Appendix 1. When we began this project, we were thinking almost exclusively in terms of long-term fertilization over large regions of the ocean such as the Southern Ocean, with much of our focus being on how ocean circulation and biogeochemical cycling would interact to control the response to a given fertilization scenario. Our research on these types of scenarios, which was carried out largely during the first three years of our project, led to several major new insights on the interaction between ocean biogeochemistry and circulation. This work, which is described in the following Section II on “Large scale fertilization,” has continued to appear in the literature over the past few years, including two high visibility papers in Nature. Early on in the first three years of our project, it became clear that small "patch-scale" fertilizations over limited regions of order 100 km diameter were much more likely than large scale fertilization, and we carried out a series of idealized patch fertilization simulations reported on in Gnanadesikan et al. (2003). Based on this paper and other results we had obtained by the end of our first three-year grant, we identified a number of important issues that needed to be addressed in the second three-year period of this grant. Section III on “patch fertilization” discusses the major findings of this phase of our research, which is described in two major manuscripts that will be submitted for publication in the near future. This research makes use of new more realistic ocean ecosystem and iron cycling models than our first paper on this topic. We have several major new insights into what controls the efficiency of iron fertilization in the ocean. Section IV on “model development” summarizes a set of papers describing the progress that we made on improving the ecosystem models we use for our iron fertilization simulations.

Jorge L. Sarmiento - Princeton PI, Anand Gnanadesikan - Princeton Co-I, Nicolas Gruber - UCLA PI, Xin Jin - UCLA PostDoc, Robert Armstrong - SUNY /Stony Brook Consultant

2007-06-21T23:59:59.000Z

343

ACTINIDE REMOVAL PROCESS SAMPLE ANALYSIS, CHEMICAL MODELING, AND FILTRATION EVALUATION  

SciTech Connect (OSTI)

Filtration within the Actinide Removal Process (ARP) currently limits the throughput in interim salt processing at the Savannah River Site. In this process, batches of salt solution with Monosodium Titanate (MST) sorbent are concentrated by crossflow filtration. The filtrate is subsequently processed to remove cesium in the Modular Caustic Side Solvent Extraction Unit (MCU) followed by disposal in saltstone grout. The concentrated MST slurry is washed and sent to the Defense Waste Processing Facility (DWPF) for vitrification. During recent ARP processing, there has been a degradation of filter performance manifested as the inability to maintain high filtrate flux throughout a multi-batch cycle. The objectives of this effort were to characterize the feed streams, to determine if solids (in addition to MST) are precipitating and causing the degraded performance of the filters, and to assess the particle size and rheological data to address potential filtration impacts. Equilibrium modelling with OLI Analyzer{sup TM} and OLI ESP{sup TM} was performed to determine chemical components at risk of precipitation and to simulate the ARP process. The performance of ARP filtration was evaluated to review potential causes of the observed filter behavior. Task activities for this study included extensive physical and chemical analysis of samples from the Late Wash Pump Tank (LWPT) and the Late Wash Hold Tank (LWHT) within ARP as well as samples of the tank farm feed from Tank 49H. The samples from the LWPT and LWHT were obtained from several stages of processing of Salt Batch 6D, Cycle 6, Batch 16.

Martino, C.; Herman, D.; Pike, J.; Peters, T.

2014-06-05T23:59:59.000Z

344

Forecasting a large number of tropical cyclone intensities around Japan using a high-resolution atmosphere-ocean coupled model  

Science Journals Connector (OSTI)

This work quantifies the benefits of using a high-resolution atmosphere-ocean coupled model in the tropical cyclone (TC) intensity forecasts in the vicinity of Japan. To do so, a large number of high-resolution calculations were performed by ...

Kosuke Ito; Tohru Kuroda; Kazuo Saito; Akiyoshi Wada

345

Model for a Josephson junction array coupled to a resonant cavity J. Kent Harbaugh and D. Stroud  

E-Print Network [OSTI]

Model for a Josephson junction array coupled to a resonant cavity J. Kent Harbaugh and D. Stroud junctions, there is a transition from incoherence to coherence as a function of N, the number of Josephson-capacitance and underdamped Josephson junctions, quantum phase fluctua- tions inhibit phase locking.8­13 Thus, until recently

Stroud, David

346

Energies and analytic gradients for a coupled-cluster doubles model using variational Brueckner orbitals: Application to symmetry breaking  

E-Print Network [OSTI]

Energies and analytic gradients for a coupled-cluster doubles model using variational Brueckner Brueckner orbitals in ab initio electronic structure theory. Whereas approximate Brueckner orbitals have Brueckner orbitals. These two procedures yield the same set of exact Brueckner orbitals in the full

Krylov, Anna I.

347

2D Axisymmetric Coupled CFD-kinetics Modeling of a Nonthermal Arc Plasma Torch for Diesel Fuel  

E-Print Network [OSTI]

-assisted diesel fuel reformer developed for two different applications: (i) onboard H2 production for fuel cell been also developed for different reforming reactors: solid oxide fuel cell (SOFC)7 , membrane reformer1 2D Axisymmetric Coupled CFD-kinetics Modeling of a Nonthermal Arc Plasma Torch for Diesel Fuel

Boyer, Edmond

348

Comparative study of laminar and turbulent flow model with different operating parameters for radio frequency-inductively coupled plasma torch working at 3??MHz frequency at atmospheric pressure  

Science Journals Connector (OSTI)

This paper provides 2D comparative study of results obtained using laminar and turbulent flow model for RF (radio frequency) Inductively Coupled Plasma (ICP) torch. The study was done for the RF-ICP torch operating at 50?kW DC power and 3?MHz frequency located at BARC. The numerical modeling for this RF-ICP torch is done using ANSYS software with the developed User Defined Function. A comparative study is done between laminar and turbulent flow model to investigate how temperature and flow fields change when using different operating conditions such as (a) swirl and no swirl velocity for sheath gas flow rate (b) variation in sheath gas flow rate and (c) variation in plasma gas flow rate. These studies will be useful for different material processing applications.

Sangeeta B. Punjabi; S. N. Sahasrabudhe; N. K. Joshi; H. A. Mangalvedekar; A. K. Das; D. C. Kothari

2014-01-01T23:59:59.000Z

349

Processing of cloud condensation nuclei by collision-coalescence in a mesoscale model  

E-Print Network [OSTI]

The Naval Research Laboratory's Coupled Ocean-Atmosphere Mesoscale Prediction System (COAMPS) is employed to explore the relative importance of source, sink, and transport processes in producing an accurate forecast of the ...

Mechem, David B.; Robinson, Paul C.; Kogan, Yefim L.

2006-09-26T23:59:59.000Z

350

Analytical impurity transport model: Coupling between particle and charge state transports in tokamak plasmas  

SciTech Connect (OSTI)

Interpretation and understanding of a set of coupled continuity equations commonly used in impurity tokamak transport studies are found to be syncretic and inadequate, since they do not distinguish between the cross-field fluxes of impurity particles and of their charge states (cs). An analytical approach to impurity transport studies previously developed is generalized to the case of diffusive-convective cs dynamics and provides a set of dimensionless parameters to describe the impurity behavior more correctly than using empirical coefficients D and V, which, in turn, have to be interpreted in terms of their cs, rather than of particles. An analytical transport model (ATM) with underlying interpretation is proposed. It is based on the solutions of two separate transport problems for impurity cs and particles instead of a single one. It is shown that ATM consistently explains two groups of available empirical dependences regarding the scaling D{proportional_to}n{sub e}{sup -1} and the profiles of V/D, which are shown to be the density profile gradients, {nabla}n{sub Z}/n{sub Z} and suggests the neoclassical scale of the particle diffusion coefficient.

Shurygin, V. A. [Nuclear Fusion Institute, Russian Research Centre Kurchatov Institute, Kurchatov Sq. 1, Moscow, 123182 (Russian Federation)

2008-01-15T23:59:59.000Z

351

Characterization of U(VI) Sorption-Desorption Processes and Model Upscaling  

SciTech Connect (OSTI)

The objectives of the overall collaborative EMSP effort (with which this project is associated) were to characterize sorption and desorption processes of U(VI) on pristine and contaminated Hanford sediments over a range of sediment facies and materials properties and to relate such characterization both to fundamental molecular-scale understanding and field-scale models of geochemistry and mass transfer. The research was intended to provide new insights on the mechanisms of U(VI) retardation at Hanford, and to allow the development of approaches by which laboratory-developed geochemical models could be upscaled for defensible field-scale predictions of uranium transport in the environment. Within this broader context, objectives of the JHU-based project were to test hypotheses regarding the coupled roles of adsorption and impermeable-zone diffusion in controlling the fate and transport of U(VI) species under conditions of comparatively short-term exposure. In particular, this work tested the following hypotheses: (1) the primary adsorption processes in the Hanford sediment over the pH range of 7 to 10 are surface complexation reactions of aqueous U(VI) hydroxycarbonate and carbonate complexes with amphoteric edge sites on detrital phyllosilicates in the silt/clay size fraction; (2) macroscopic adsorption intensity (at given aqueous conditions) is a function of mineral composition and aquatic chemistry; and (3) equilibrium sorption and desorption to apply in short-term, laboratory-spiked pristine sediments; and (4) interparticle diffusion can be fully understood in terms of a model that couples molecular diffusion of uranium species in the porewater with equilibrium sorption under the relevant aqueous conditions. The primary focus of the work was on developing and applying both models and experiments to test the applicability of "local equilibrium" assumptions in the modeling interpretation of sorption retarded interparticle diffusion, as relevant to processes of U(VI) diffusion in silt/clay layers. Batch isotherm experiments were first used to confirm sorption isotherms under the intended test conditions and diffusion cell experiments were then conducted to explore the diffusion hypotheses. Important new information was obtained about the role of aqueous calcium and solid calcium carbonate in controlling sorption equilibrium with Hanford sediments. The retarded interparticle diffusion model with local sorption equilibrium was shown to very successfully simulate diffusion at high aqueous concentration of U(VI). By contrast, however, diffusion data obtained at low concentration suggested nonequilibrium of sorption even at diffusion time scales. Such nonequilibrium effects at low concentration are likely to be the result of sorption retarded intraparticle diffusion, and strong U(VI) sorption in the low concentration range.

Bai, Jing; Dong, Wenming; Ball, William P.

2006-10-12T23:59:59.000Z

352

Analysis and Geochemical Modeling of Vanadium Contamination in Groundwater New Rifle Processing Site, Colorado  

Broader source: Energy.gov [DOE]

Analysis and Geochemical Modeling of Vanadium Contamination in Groundwater New Rifle Processing Site, Colorado

353

Impact of Agricultural Practice on Regional Climate in a CoupledLand Surface Mesoscale Model  

SciTech Connect (OSTI)

The land surface has been shown to form strong feedbacks with climate due to linkages between atmospheric conditions and terrestrial ecosystem exchanges of energy, momentum, water, and trace gases. Although often ignored in modeling studies, land management itself may form significant feedbacks. Because crops are harvested earlier under drier conditions, regional air temperature, precipitation, and soil moisture, for example, affect harvest timing, particularly of rain-fed crops. This removal of vegetation alters the land surface characteristics and may, in turn, affect regional climate. We applied a coupled climate(MM5) and land-surface (LSM1) model to examine the effects of early and late winter wheat harvest on regional climate in the Department of Energy Atmospheric Radiation Measurement (ARM) Climate Research Facility in the Southern Great Plains, where winter wheat accounts for 20 percent of the land area. Within the winter wheat region, simulated 2 m air temperature was 1.3 C warmer in the Early Harvest scenario at mid-day averaged over the two weeks following harvest. Soils in the harvested area were drier and warmer in the top 10 cm and wetter in the 10-20 cm layer. Midday soils were 2.5 C warmer in the harvested area at mid-day averaged over the two weeks following harvest. Harvest also dramatically altered latent and sensible heat fluxes. Although differences between scenarios diminished once both scenarios were harvested, the short-term impacts of land management on climate were comparable to those from land cover change demonstrated in other studies.

Cooley, H.S.; Riley, W.J.; Torn, M.S.; He, Y.

2004-07-01T23:59:59.000Z

354

Use of Brueckner orbitals in second-order approximate coupled-cluster with singles and doubles (CC2) model  

Science Journals Connector (OSTI)

Brueckner orbitals are introduced into the CC2 (second-order approximate coupled-cluster with singles and doubles) model. The computational cost of the Brueckner CC2 model is virtually identical to the conventional CC2 model. Brueckner CC2 is tested for the ground-state energies of several well-defined molecules as well as problematic ones. Significant improvement compared to the conventional CC2 model is observed when large orbital relaxation is invoked. Evaluation of analytical gradients and excited states is also discussed.

Yoshinobu Akinaga; Yukio Kawashima; Seiichiro Ten-no

2011-01-01T23:59:59.000Z

355

Towards Flexible and High-Level Modeling and Enacting of Processes  

Science Journals Connector (OSTI)

Process modeling and enacting concepts are at the center of workflow management. Support for heterogeneous processes, flexibility, reuse, and distribution are great challenges for the design of the next generation process modeling languages and their ...

Gregor Joeris; Otthein Herzog

1999-06-01T23:59:59.000Z

356

Evolutionary Processes in Economics: Multi-agent Model of Macrogenerations Dynamics  

E-Print Network [OSTI]

Evolutionary Processes in Economics: Multi-agent Model of Macrogenerations Dynamics Kateryna macroeconomic growth as an evolutionary process. Keywords. Economic growth, evolutionary theory, multi]. Our study models the economic growth as an evolutionary process, where the term `macrogeneration

López-Sánchez, Maite

357

Modelling and Simulation of Process Configurations Combining Distillation and Reaction.  

E-Print Network [OSTI]

??Process intensification refers to technologies and strategies that enable simpler and more efficient processes compared to conventional processes. Some features of such intensified processes are… (more)

Jakobsson, Kaj

2005-01-01T23:59:59.000Z

358

Modelling and simulation of process configurations combining distillation and reaction.  

E-Print Network [OSTI]

??Process intensification refers to technologies and strategies that enable simpler and more efficient processes compared to conventional processes. Some features of such intensified processes are… (more)

Jakobsson, Kaj

2005-01-01T23:59:59.000Z

359

Modeling languages for business processes and business rules: A representational analysis  

Science Journals Connector (OSTI)

Process modeling and rule modeling languages are both used to document organizational policies and procedures. To date, their synergies and overlap are under-researched. Understanding the relationship between the two modeling types would allow organizations ... Keywords: BPMN, BWW, Business process management, Business process modeling, Business rule modeling, PRR, Representation theory, SBVR, SRML, SWRL

Michael zur Muehlen; Marta Indulska

2010-06-01T23:59:59.000Z

360

Model and Analytic Processes for Export License Assessments  

SciTech Connect (OSTI)

This paper represents the Department of Energy Office of Nonproliferation Research and Development (NA-22) Simulations, Algorithms and Modeling (SAM) Program's first effort to identify and frame analytical methods and tools to aid export control professionals in effectively predicting proliferation intent; a complex, multi-step and multi-agency process. The report focuses on analytical modeling methodologies that alone, or combined, may improve the proliferation export control license approval process. It is a follow-up to an earlier paper describing information sources and environments related to international nuclear technology transfer. This report describes the decision criteria used to evaluate modeling techniques and tools to determine which approaches will be investigated during the final 2 years of the project. The report also details the motivation for why new modeling techniques and tools are needed. The analytical modeling methodologies will enable analysts to evaluate the information environment for relevance to detecting proliferation intent, with specific focus on assessing risks associated with transferring dual-use technologies. Dual-use technologies can be used in both weapons and commercial enterprises. A decision-framework was developed to evaluate which of the different analytical modeling methodologies would be most appropriate conditional on the uniqueness of the approach, data availability, laboratory capabilities, relevance to NA-22 and Office of Arms Control and Nonproliferation (NA-24) research needs and the impact if successful. Modeling methodologies were divided into whether they could help micro-level assessments (e.g., help improve individual license assessments) or macro-level assessment. Macro-level assessment focuses on suppliers, technology, consumers, economies, and proliferation context. Macro-level assessment technologies scored higher in the area of uniqueness because less work has been done at the macro level. An approach to developing testable hypotheses for the macro-level assessment methodologies is provided. The outcome of this works suggests that we should develop a Bayes Net for micro-level analysis and continue to focus on Bayes Net, System Dynamics and Economic Input/Output models for assessing macro-level problems. Simultaneously, we need to develop metrics for assessing intent in export control, including the risks and consequences associated with all aspects of export control.

Thompson, Sandra E.; Whitney, Paul D.; Weimar, Mark R.; Wood, Thomas W.; Daly, Don S.; Brothers, Alan J.; Sanfilippo, Antonio P.; Cook, Diane; Holder, Larry

2011-09-29T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


361

Thermally Coupled Catalytic Reactor for Steam Reforming of Methane and Liquid Hydrocarbons: Experiment and Mathematical Modeling  

Science Journals Connector (OSTI)

An energy-efficient catalytic reactor for producing synthesis gas from methane and liquid hydrocarbons is proposed that is ... on the coupling of an endothermic reaction (steam reforming of methane, hexane, or is...

V. A. Kirillov; N. A. Kuzin; A. V. Kulikov…

2003-05-01T23:59:59.000Z

362

A Review of Ground Coupled Heat Pump Models Used in Whole-Building Computer Simulation Programs  

E-Print Network [OSTI]

Increasingly, building owners are turning to ground source heat pump (GSHP) systems to improve energy efficiency. Ground-coupled heat pump (GCHP) systems with a vertical closed ground loop heat exchanger are one of the more widely used systems. Over...

Do, S. L.; Haberl, J. S.

363

Magneto-Thermo-Mechanical Coupling, Stability Analysis and Phenomenological Constitutive Modeling of Magnetic Shape Memory Alloys  

E-Print Network [OSTI]

equations are then reduced to capture variant reorientation. A coupled magneto-mechanical boundary value problem (BVP) is solved that accounts for variant reorientation to investigate the influence of the demagnetization effect on the magnetic field...

Haldar, Krishnendu 1978-

2012-12-06T23:59:59.000Z

364

Coupling GIS and LCA for biodiversity assessments of land use: Part 1: Inventory modeling  

E-Print Network [OSTI]

467 DOI 10.1007/s11367-010-0170-9 LAND USE IN LCA CouplingGIS and LCA for biodiversity assessments of land use Part 1:while life cycle assessment (LCA) does not conventionally

Geyer, Roland; Stoms, David M.; Lindner, Jan P.; Davis, Frank W.; Wittstock, Bastian

2010-01-01T23:59:59.000Z

365

A model to evaluate the coupling characteristics from a coaxial line into a cylindrical waveguide  

E-Print Network [OSTI]

The current method of evaluating the coupling characteristics for a resonant microwave cavity sensor, such as that for the Flexured Mass Accelerometer, is limited to finite-element analysis, which takes approximately five ...

Youn, Michelle S. (Michelle Soyeoun), 1979-

2001-01-01T23:59:59.000Z

366

State estimation of the Labrador Sea with a coupled sea ice-ocean adjoint model  

E-Print Network [OSTI]

Sea ice (SI) and ocean variability in marginal polar and subpolar seas are closely coupled. SI variability in the Labrador Sea is of climatic interest because of its relationship to deep convection/mode water formation, ...

Fenty, Ian Gouverneur

2010-01-01T23:59:59.000Z

367

Short communication Dynamics of a model of two delay-coupled relaxation oscillators  

E-Print Network [OSTI]

: Coupled oscillators Devil's Staircase Delay-differential equations a b s t r a c t This paper investigates by regions of complicated dynamics, reminiscent of the Devil's Staircase. Stability of motions in the in

Rand, Richard H.

368

GFDL’s ESM2 Global Coupled Climate–Carbon Earth System Models. Part I: Physical Formulation and Baseline Simulation Characteristics  

Science Journals Connector (OSTI)

The physical climate formulation and simulation characteristics of two new global coupled carbon–climate Earth System Models, ESM2M and ESM2G, are described. These models demonstrate similar climate fidelity as the Geophysical Fluid Dynamics ...

John P. Dunne; Jasmin G. John; Alistair J. Adcroft; Stephen M. Griffies; Robert W. Hallberg; Elena Shevliakova; Ronald J. Stouffer; William Cooke; Krista A. Dunne; Matthew J. Harrison; John P. Krasting; Sergey L. Malyshev; P. C. D. Milly; Peter J. Phillipps; Lori T. Sentman; Bonita L. Samuels; Michael J. Spelman; Michael Winton; Andrew T. Wittenberg; Niki Zadeh

2012-10-01T23:59:59.000Z

369

Coupling a Mesoscale Numerical Weather Prediction Model with Large-Eddy Simulation for Realistic Wind Plant Aerodynamics Simulations (Poster)  

SciTech Connect (OSTI)

Wind plant aerodynamics are influenced by a combination of microscale and mesoscale phenomena. Incorporating mesoscale atmospheric forcing (e.g., diurnal cycles and frontal passages) into wind plant simulations can lead to a more accurate representation of microscale flows, aerodynamics, and wind turbine/plant performance. Our goal is to couple a numerical weather prediction model that can represent mesoscale flow [specifically the Weather Research and Forecasting model] with a microscale LES model (OpenFOAM) that can predict microscale turbulence and wake losses.

Draxl, C.; Churchfield, M.; Mirocha, J.; Lee, S.; Lundquist, J.; Michalakes, J.; Moriarty, P.; Purkayastha, A.; Sprague, M.; Vanderwende, B.

2014-06-01T23:59:59.000Z

370

Ab initio potential-energy curves and radial and rotational couplings for the process N5++He?N4++He+  

Science Journals Connector (OSTI)

Potential-energy curves of six ?+1, two ?1, and one ?1 states have been determined for the N5++He?N4++He+ process by means of ab initio calculations with configuration interaction. The matrix elements of the operator d/dR between the four ?+1 states and the two ?1 states involved in the collisional process have been calculated by the rigorous finite-difference technique. A very peaked radial coupling matrix element is observed at 8.30 a.u. corresponding to an avoided crossing between the entry channel and the ?+1 state dissociating to {N4+(3d)+He+}. Two other avoided crossings between ?+1 states are observable at 7.50 and 6.35 a.u. Rotational and radial couplings involving ?1 states have also been determined.

Marie-Christine Bacchus-Montabonel

1987-09-01T23:59:59.000Z

371

Fundamental Chemical Kinetic And Thermodynamic Data For Purex Process Models  

SciTech Connect (OSTI)

To support either the continued operations of current reprocessing plants or the development of future fuel processing using hydrometallurgical processes, such as Advanced Purex or UREX type flowsheets, the accurate simulation of Purex solvent extraction is required. In recent years we have developed advanced process modeling capabilities that utilize modern software platforms such as Aspen Custom Modeler and can be run in steady state and dynamic simulations. However, such advanced models of the Purex process require a wide range of fundamental data including all relevant basic chemical kinetic and thermodynamic data for the major species present in the process. This paper will summarize some of these recent process chemistry studies that underpin our simulation, design and testing of Purex solvent extraction flowsheets. Whilst much kinetic data for actinide redox reactions in nitric acid exists in the literature, the data on reactions in the diluted TBP solvent phase is much rarer. This inhibits the accurate modelization of the Purex process particularly when species show a significant extractability in to the solvent phase or when cycling between solvent and aqueous phases occurs, for example in the reductive stripping of Pu(IV) by ferrous sulfamate in the Magnox reprocessing plant. To support current oxide reprocessing, we have investigated a range of solvent phase reactions: - U(IV)+HNO{sub 3}; - U(IV)+HNO{sub 2}; - U(IV)+HNO{sub 3} (Pu catalysis); - U(IV)+HNO{sub 3} (Tc catalysis); - U(IV)+ Np(VI); - U(IV)+Np(V); - Np(IV)+HNO{sub 3}; - Np(V)+Np(V); Rate equations have been determined for all these reactions and kinetic rate constants and activation energies are now available. Specific features of these reactions in the TBP phase include the roles of water and hydrolyzed intermediates in the reaction mechanisms. In reactions involving Np(V), cation-cation complex formation, which is much more favourable in TBP than in HNO{sub 3}, also occurs and complicates the redox chemistry. Whilst some features of the redox chemistry in TBP appear similar to the corresponding reactions in aqueous HNO{sub 3}, there are notable differences in rates, the forms of the rate equations and mechanisms. Secondly, to underpin the development of advanced single cycle flowsheets using the complexant aceto-hydroxamic acid, we have also characterised in some detail its redox chemistry and solvent extraction behaviour with both Np and Pu ions. We find that simple hydroxamic acids are remarkably rapid reducing agents for Np(VI). They also reduce Pu(VI) and cause a much slower reduction of Pu(IV) through a complex mechanism involving acid hydrolysis of the ligand. AHA is a strong hydrophilic and selective complexant for the tetravalent actinide ions as evidenced by stability constant and solvent extraction data for An(IV), M(III) and U(VI) ions. This has allowed the successful design of U/Pu+Np separation flowsheets suitable for advanced fuel cycles. (authors)

Taylor, R.J.; Fox, O.D.; Sarsfield, M.J.; Carrott, M.J.; Mason, C.; Woodhead, D.A.; Maher, C.J. [British Technology Centre, Nexia Solutions, Sellafield, Seascale, CA20 1PG (United Kingdom); Steele, H. [Nexia Solutions, inton House, Risley, Warrington, WA3 6AS (United Kingdom); Koltunov, V.S. [A.A. Bochvar All-Russia Institute of Inorganic Materials, VNIINM, PO Box 369, Moscow 123060 (Russian Federation)

2007-07-01T23:59:59.000Z

372

Modeling land surface processes of the midwestern United States : predicting soil moisture under a warmer climate  

E-Print Network [OSTI]

This dissertation seeks to quantify the response of soil moisture to climate change in the midwestern United States. To assess this response, a dynamic global vegetation model, Integrated Biosphere Simulator, was coupled ...

Winter, Jonathan (Jonathan Mark)

2010-01-01T23:59:59.000Z

373

Investigating the Correspondence Between Transcriptomic and Proteomic Expression Profiles Using Coupled Cluster Models.  

SciTech Connect (OSTI)

Modern transcriptomics and proteomics enable us to survey the expression of RNAs and proteins at large scales. While these data are usually generated and analysed separately, there is an increasing interest in comparing and co-analysing transcriptome and proteome expression data. A major open question is whether transcriptome and proteome expression is linked and how it is coordinated. Results: Here we have developed a probabilistic clustering model that permits analysis of the links between transcriptomic and proteomic profiles in a sensible and flexible manner. Our coupled mixture model defines a prior probability distribution over the component to which a protein profile should be assigned conditioned on which component the associated mRNA profile belongs to. By providing probabilistic assignments this approach sits between the two extremes of concatenating the data on the assumption that mRNA and protein clusters would have a one-to-one relationship, and independent clustering where the mRNA profile provides no information on the protein profile and vice-versa. We apply this approach to a large dataset of quantitative transcriptomic and proteomic expression data obtained from a human breast epithelial cell line (HMEC) stimulated by epidermal growth factor (EGF) over a series of timepoints corresponding to one cell cycle. The results reveal a complex relationship between transcriptome and proteome with most mRNA clusters linked to at least two protein clusters, and vice versa. A more detailed analysis incorporating information on gene function from the gene ontology database shows that a high correlation of mRNA and protein expression is limited to the components of some molecular machines, such as the ribosome, cell adhesion complexes and the TCP-1 chaperonin involved in protein folding. Conclusions: The dynamic regulation of the transcriptome and proteome in mammalian cells in response to an acute mitogenic stimulus appears largely independent with very little correspondence between mRNA and protein expression. The exceptions involve a few selected multi-protein complexes that require the stoichiometric expression of components for correct function. This finding has wide ramifications regarding the understanding of gene and protein expression including its control and evolution. It also shows that transcriptomic and proteomic expression analysis are complementary and non-redundant.

Rogers, Simon; Girolami, Mark; Kolch, Walter; Waters, Katrina M.; Liu, Tao; Thrall, Brian D.; Wiley, H. S.

2008-12-01T23:59:59.000Z

374

The Benchmark Evaluation Process: From Experimental Data to Benchmark Model  

SciTech Connect (OSTI)

The International Criticality Safety Benchmark Evaluation Project (ICSBEP) provides a handbook of descriptions, evaluations, and models of experiments with fissionable material. The 'International Handbook of Evaluated Criticality Safety Benchmark Experiments' (ICSBEP Handbook) is useful for criticality safety analysts and nuclear-data evaluators for validation of neutron transport codes and nuclear cross-section sets. Each of the four main parts of the ICSBEP document provides valuable information. The four parts are as follows: Part 1, detailed description of the experiment; Part 2, evaluation of experimental data to obtain parameter values that define the model and their uncertainties; Part 3, derivation and concise description of the benchmark model; and Part 4, sample calculation results. The ICSBEP Handbook provides a practical, standardized format for documenting nuclear experiments.Valuable, previously unknown data are often discovered during the evaluation process. Besides these discoveries, many other things have been learned during this first decade of evaluating and providing benchmark models of experiments. The current method is described in order to improve understanding of what is required to evaluate benchmark experiments for validation purposes.

Dean, Virginia A.F. [Consultant, Idaho National Engineering and Environmental Laboratory (United States)

2003-09-15T23:59:59.000Z

375

Improvement of Moist and Radiative Processes in Highly Parallel Atmospheric General Circulation Models: Validation and Development  

SciTech Connect (OSTI)

Research on designing an integrated moist process parameterization package was carried. This work began with a study that coupled an ensemble of cloud models to a boundary layer model to examine the feasibility of such a methodology for linking boundary layer and cumulus parameterization schemes. The approach proved feasible, prompting research to design and evaluate a coupled parameterization package for GCMS. This research contributed to the development of an Integrated Cumulus Ensemble-Turbulence (ICET) parameterization package. This package incorporates a higher-order turbulence boundary layer that feeds information concerning updraft properties and the variances of temperature and water vapor to the cloud parameterizations. The cumulus ensemble model has been developed, and initial sensitivity tests have been performed in the single column model (SCM) version of CCM2. It is currently being coupled to a convective wake/gust front model. The major function of the convective wake/gust front model is to simulate the partitioning of the boundary layer into disturbed and undisturbed regions. A second function of this model is to predict the nonlinear enhancement of surface to air sensible heat and moisture fluxes that occur in convective regimes due to correlations between winds and anomalously cold, dry air from downdrafts in the gust front region. The third function of the convective wake/gust front model is to predict the amount of undisturbed boundary layer air lifted by the leading edge of the wake and the height to which this air is lifted. The development of the wake/gust front model has been completed, and it has done well in initial testing as a stand-alone component. The current task, to be completed by the end of the funding period, is to tie the wake model to a cumulus ensemble model and to install both components into the single column model version of CCM3 for evaluation. Another area of parametrization research has been focused on the representation of cloud radiative properties. An examination of the CCM2 simulation characteristics indicated that many surface temperature and warm land precipitation problems were linked to deficiencies in the specification of cloud optical properties, which allowed too much shortwave radiation to reach the surface. In-cloud liquid water path was statically specified in the CCM2 using a "prescribed, meridionally and height varying, but time independent, cloud liquid water density profile, which was analytically determined from a meridionally specified liquid water scale height. Single-column model integrations were conducted to explore alternative formulations for the cloud liquid water path diagnostic, converging on an approach that employs a similar, but state-dependent technique for determining in-cloud liquid water concentration. The new formulation, results in significant improvements to both the top-of- atmosphere and surface energy budgets. In particular, when this scheme is incorporated in the three-dimensional GCM, simulated July surface temperature biases are substantially reduced, where summer precipitation over the northern hemisphere continents, as well as precipitation rates over most all warm land areas, is more consistent with observations". This improved parameterization has been incorporated in the CCM3.

Frank, William M.; Hack, James J.; Kiehl, Jeffrey T.

1997-02-24T23:59:59.000Z

376

A Model for the Visualization Exploration Process T.J. Jankun-Kelly  

E-Print Network [OSTI]

A Model for the Visualization Exploration Process T.J. Jankun-Kelly Kwan-Liu Ma Michael Gertz of the visualization exploration process. The model, based upon a new parameter derivation calculus, can be used the visualization process to further data exploration. Keywords: visualization process, visualization models, visual

Ma, Kwan-Liu

377

Coupling and comparing a spatially- and temporally-detailed eutrophication model with an ecosystem network model: An initial application to Chesapeake Bay  

Science Journals Connector (OSTI)

Coastal waters are modeled for a variety of purposes including eutrophication remediation and fisheries management. Combining these two approaches provides insights which are not available from either approach independently. Coupling is confounded, however, ... Keywords: Atlantic menhaden, CE-QUAL-ICM, Chesapeake Bay, Ecopath, Eutrophication, Phytoplankton

Carl F. Cerco; Dorothy Tillman; James D. Hagy

2010-04-01T23:59:59.000Z

378

Modeling Coupled Hydrologic and Chemical Processes: Long-Term Uranium Transport following Phosphorus Fertilization  

Science Journals Connector (OSTI)

...mainly 226Ra and 210Pb) and rare earth elements originating...Phosphoric acid and the byproduct phosphogypsum are produced using H2SO4...the following reaction: Phosphogypsum (a calcium sulfate dihydrate...2006. The application of phosphogypsum in agriculture and the radiological...

D. Jacques; J. Šim?nek; D. Mallants; M.Th. van Genuchten

379

Report on Modeling Coupled Processes in the Near Field of a Clay Repository  

E-Print Network [OSTI]

J.W. (2001) Hydraulic Fracturing during the Formation andconditions can cause hydraulic fracturing if Report oncases evidence of hydraulic fracturing has been preserved by

Liu, H.-H.

2014-01-01T23:59:59.000Z

380

Coupled modeling of grounddwater flow solute transport, chemical reactions and microbial processes in the "SP" island  

E-Print Network [OSTI]

rock /SKB, 1995/. Underground facilities will have to beis a prototype, full-scale underground facility launched andof Stockholm. The underground facility consists of a 3,600 m

Samper, Javier; Molinero, Jorg; Changbing, Yang; Zhang, Guoxiang

2003-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

A Strategy for Process-Oriented Validation of Coupled Chemistry–Climate Models  

Science Journals Connector (OSTI)

Accurate and reliable predictions and an understanding of future changes in the stratosphere are major aspects of the subject of climate change. Simulating the interaction between chemistry and climate is of particular importance, because ...

V. Eyring; N. R. P. Harris; M. Rex; T. G. Shepherd; D. W. Fahey; G. T. Amanatidis; J. Austin; M. P. Chipperfield; M. Dameris; P. M. De F. Forster; A. Gettelman; H. F. Graf; T. Nagashima; P. A. Newman; S. Pawson; M. J. Prather; J. A. Pyle; R. J. Salawitch; B. D. Santer; D. W. Waugh

2005-08-01T23:59:59.000Z

382

Coupled modeling of grounddwater flow solute transport, chemical reactions and microbial processes in the "SP" island  

E-Print Network [OSTI]

in cements is the ettringite (a highly soluble calcium andBrucite Foshagite Calcite Ettringite Recharge water Na Ca Mg

Samper, Javier; Molinero, Jorg; Changbing, Yang; Zhang, Guoxiang

2003-01-01T23:59:59.000Z

383

Computational fluid dynamics model development on transport phenomena coupling with reactions in intermediate temperature solid oxide fuel cells  

Science Journals Connector (OSTI)

A 3D model is developed to describe an anode-supported planar solid oxide fuel cell (SOFC) by ANSYS/Fluent evaluating reactions including methane steam reforming (MSR)/water-gas shift (WGSR) reactions in thick anode layer and H2-O2/CO-O2 electrochemical reactions in anode active layer coupled with heat mass species momentum and ion/electron charges transport processes in SOFC. The predicted results indicate that electron/ion exchange appears in the very thin region in active layers (0.018?mm in anode and 0.01?mm in cathode) based on three phase boundary operating temperature and concentration of reactants (mainly H2). Active polarization happening in active layers dominates over concentration and ohmic losses. High gradient of current density exists near interface between electrode and solid conductor due to the block by gas channel. It is also found the reaction rates of MSR and WGSR along main flow direction and cell thickness direction decrease due to low concentration of fuel (CH4) caused by mass consumption. With increasing operating temperature from 978?K to 1088?K the current density and the reaction rate of MSR are increased by 10.8% and 5.4% respectively. While ion current density is 52.9% higher than in standard case and H2 is consumed by 5.1% more when ion conductivity is doubled. CO-O2 has been considered in charge transfer reaction in anode active layer and it is found that the current density and species distributions are not sensitive but WGSR reaction will be forced backwards to supply more CO for CO-O2 electrochemical reaction.

Chao Yang; Guogang Yang; Danting Yue; Jinliang Yuan; Bengt Sunden

2013-01-01T23:59:59.000Z

384

Evaluation of ground movement and damage to structures from Chinese coal mining using a new GIS coupling model  

Science Journals Connector (OSTI)

In this paper, combining a theoretical method of predicting subsidence over time and using a geographical information system (GIS), a GIS-based dynamic model is proposed to rapid simulate the phenomenon of progressive movement distribution from large sequential mining. The theoretical method uses stochastic medium concept involving Knothe time function for basic governing equations to calculate progressive movement because this solutions have been widely developed and used in Chinese mining practice to solve the coal extraction problem under building, railways, and rivers. In order to assess the impact of progressive movement to the surface structures, a fuzzy model is suggested to identify damage classifications with contributions of subsidence calculations and building mesh data. For implementation of the GIS-based prediction and assessment model, a new GIS coupling model is established by implementing tight coupling strategy using the component object model (COM) program to overcome the problems of complex model integration for dynamic prediction and assessment. Furthermore, this paper demonstrates the effectiveness of this GIS-based model for prediction and evaluation of subsidence-induced damage from coal mining beneath surface structures in China.

Ibrahim Djamaluddin; Yasuhiro Mitani; Tetsuro Esaki

2011-01-01T23:59:59.000Z

385

Coupled Geochemical and Hydrological Processes Governing the Fate and Transport of Radionuclides and Toxic Metals Beneath the Hanford Tank Farms  

SciTech Connect (OSTI)

The goal of this research was to provide an improved understanding and predictive capability of coupled hydrological and geochemical mechanisms that are responsible for the accelerated migration and immobilization of radionuclides and toxic metals in the badose zone beneath the Hanford Tank Farms.

Scott Fendorf; Phil Jardine

2006-07-21T23:59:59.000Z

386

Partition wall subsystem modeling and effect on the coupled building system response  

E-Print Network [OSTI]

Building Design and Modeling baseline. 5.3 Building Design and Modeling Three reinforcedthe bare building (no wall), the modeling efforts neglected

Wood, Richard Lee

2012-01-01T23:59:59.000Z

387

MODELING THE INFLUENCE OF HETEROGENEITY AND ANISOTROPY ON PHYSICAL PROCESSES IN  

E-Print Network [OSTI]

the interplay of coupled physical and chemical processes interacting in partially water- saturated waste rock the piles. This process is a much more efficient oxygen transport mechanism than diffusion and it sustains of existing piles and guidelines on constructing new pile with minimal ARD production. Aubertin et al. (2005

Aubertin, Michel

388

Identifying acoustical coupling by measurements and prediction-models for St. Peter’s Basilica in Rome  

Science Journals Connector (OSTI)

St. Peter’s Basilica is one of the largest buildings in the world having a huge volume resulting from the addition of different parts. Consequently sound propagation cannot be interpreted using a conventional approach and requires experimental measures to be compared with statistical-acoustics and geometrical predictions in order to explain the interplay between shape materials and sound waves better. In previous research one of the most evident effects the surprisingly low reverberation time was believed to result from acoustical coupling phenomena. Taking advantage of more refined measuring techniques available today an acoustic survey was carried out and the results were analyzed using different methods including Bayesian parameter estimation of multiple slope decays and directional energy plots which showed that coupling effects actually take place even though measured reverberation times were longer than those given in previous studies. In addition experimental results were compared with geometrical- and statistical-acoustic models of the basilica which showed that careful selection of input data and in statistical models the inclusion of phenomena such as direct sound radiation and non-diffuse energy transfer allow obtaining accurate results. Finally both models demonstrated that reduced reverberation depends more on increased absorption of decorated surfaces than on coupling effects.

Francesco Martellotta

2009-01-01T23:59:59.000Z

389

Petri-Net Simulation Model of a Nuclear Component Degradation Process , E. Zioa,b  

E-Print Network [OSTI]

1 Petri-Net Simulation Model of a Nuclear Component Degradation Process Y.F. Lia* , E. Zioa,b , Y models [2-5] and simulation models [1, 6, 7]. The analytical degradation models can be further classified

Paris-Sud XI, Université de

390

Toward Novel Hybrid Biomass, Coal, and Natural Gas Processes for Satisfying Current Transportation Fuel Demands, 1: Process Alternatives, Gasification Modeling, Process Simulation, and Economic Analysis  

Science Journals Connector (OSTI)

Toward Novel Hybrid Biomass, Coal, and Natural Gas Processes for Satisfying Current Transportation Fuel Demands, 1: Process Alternatives, Gasification Modeling, Process Simulation, and Economic Analysis ... This paper, which is the first part of a series of papers, introduces a hybrid coal, biomass, and natural gas to liquids (CBGTL) process that can produce transportation fuels in ratios consistent with current U.S. transportation fuel demands. ... Steady-state process simulation results based on Aspen Plus are presented for the seven process alternatives with a detailed economic analysis performed using the Aspen Process Economic Analyzer and unit cost functions obtained from literature. ...

Richard C. Baliban; Josephine A. Elia; Christodoulos A. Floudas

2010-07-19T23:59:59.000Z

391

NEUTRINO-COOLED ACCRETION MODEL WITH MAGNETIC COUPLING FOR X-RAY FLARES IN GAMMA-RAY BURSTS  

SciTech Connect (OSTI)

The neutrino-cooled accretion disk, which was proposed to work as the central engine of gamma-ray bursts, encounters difficulty in interpreting the X-ray flares after the prompt gamma-ray emission. In this paper, the magnetic coupling (MC) between the inner disk and the central black hole (BH) is taken into consideration. For mass accretion rates around 0.001 {approx} 0.1 M{sub Sun} s{sup -1}, our results show that the luminosity of neutrino annihilation can be significantly enhanced due to the coupling effects. As a consequence, after the gamma-ray emission, a remnant disk with mass M{sub disk} {approx}< 0.5 M{sub Sun} may power most of the observed X-ray flares with the rest frame duration less than 100 s. In addition, a comparison between the MC process and the Blandford-Znajek mechanism is shown on the extraction of BH rotational energy.

Luo Yang; Gu Weimin; Liu Tong; Lu Jufu, E-mail: guwm@xmu.edu.cn [Department of Astronomy and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005 (China)

2013-08-20T23:59:59.000Z

392

Viscosity of hadron matter within relativistic mean-field based model with scaled hadron masses and couplings  

E-Print Network [OSTI]

The shear ($\\eta$) and bulk ($\\zeta$) viscosities are calculated in a quasiparticle relaxation time approximation for a hadron matter described within the relativistic mean-field based model with scaled hadron masses and couplings. Comparison with results of other models is presented. We demonstrate that a small value of the shear viscosity to entropy density ratio required for explaining a large elliptic flow observed at RHIC may be reached in the hadron phase. Large values of the bulk viscosity are noted in case of the baryon enriched matter.

A. S. Khvorostukhin; V. D. Toneev; D. N. Voskresensky

2009-12-11T23:59:59.000Z

393

Integrated Numerical Modeling Process for Evaluating Automobile Climate Control Systems  

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

FCC-70 FCC-70 Integrated Numerical Modeling Process for Evaluating Automobile Climate Control Systems John Rugh National Renewable Energy Laboratory Copyright © 2002 Society of Automotive Engineers, Inc. ABSTRACT The air-conditioning (A/C) system compressor load can significantly impact the fuel economy and tailpipe emissions of conventional and hybrid electric automobiles. With the increasing emphasis on fuel economy, it is clear that the A/C compressor load needs to be reduced. In order to accomplish this goal, more efficient climate control delivery systems and reduced peak soak temperatures will be necessary to reduce the impact of vehicle A/C systems on fuel economy and tailpipe emissions. Good analytical techniques are important in identifying promising concepts. The goal at

394

Adaptive model predictive process control using neural networks  

DOE Patents [OSTI]

A control system for controlling the output of at least one plant process output parameter is implemented by adaptive model predictive control using a neural network. An improved method and apparatus provides for sampling plant output and control input at a first sampling rate to provide control inputs at the fast rate. The MPC system is, however, provided with a network state vector that is constructed at a second, slower rate so that the input control values used by the MPC system are averaged over a gapped time period. Another improvement is a provision for on-line training that may include difference training, curvature training, and basis center adjustment to maintain the weights and basis centers of the neural in an updated state that can follow changes in the plant operation apart from initial off-line training data.

Buescher, Kevin L. (Los Alamos, NM); Baum, Christopher C. (Mazomanie, WI); Jones, Roger D. (Espanola, NM)

1997-01-01T23:59:59.000Z

395

Adaptive model predictive process control using neural networks  

DOE Patents [OSTI]

A control system for controlling the output of at least one plant process output parameter is implemented by adaptive model predictive control using a neural network. An improved method and apparatus provides for sampling plant output and control input at a first sampling rate to provide control inputs at the fast rate. The MPC system is, however, provided with a network state vector that is constructed at a second, slower rate so that the input control values used by the MPC system are averaged over a gapped time period. Another improvement is a provision for on-line training that may include difference training, curvature training, and basis center adjustment to maintain the weights and basis centers of the neural in an updated state that can follow changes in the plant operation apart from initial off-line training data. 46 figs.

Buescher, K.L.; Baum, C.C.; Jones, R.D.

1997-08-19T23:59:59.000Z

396

Evaluation and Comparison of Ecological Models Simulating Nitrogen Processes in Treatment Wetlands,Implemented in Modelica.  

E-Print Network [OSTI]

?? Two ecological models of nitrogen processes in treatment wetlands have been evaluated and compared. These models have been implemented, simulated, and visualized in the… (more)

Edelfeldt, Stina

2005-01-01T23:59:59.000Z

397

Modeling Sorption and Exchange Processes in Column Experiments and Large Scale Field Studies  

Science Journals Connector (OSTI)

This paper demonstrates the possibilities of reactive transport modeling in predicting contaminant transport processes of laboratory and field scales. Basic approaches of reactive transport modeling are discu...

Olaf Nitzsche; Harry Vereecken

2002-04-01T23:59:59.000Z

398

Structural considerations and modeling in the synthesis of heat integrated thermally coupled distillation sequences  

E-Print Network [OSTI]

of the reduction in energy consumption, there is a price to be paid when using thermally coupled systems: 1 Mellon University. Pittsburgh, PA. USA. Abstract This paper deals with the design of mixed thermally is likely the most studied unit operation in the history of Chemical Engineering. This research effort

Grossmann, Ignacio E.

399

A new elastic model for ground coupling of geophones with spikes  

Science Journals Connector (OSTI)

...coupling of geophones with spikes Guy G. Drijkoningen 1 Frederik Rademakers 1 Evert C. Slob 1 Jacob T. Fokkema 1 1 Delft University...Technology, Applied Geophysics & Petrophysics Delft Netherlands Rademakers Frederik Author Slob Evert C. Author ecslob@tudelft.nl...

Guy G. Drijkoningen; Frederik Rademakers; Evert C. Slob; Jacob T. Fokkema

400

Development of an equipment management model to improve effectiveness of processes  

SciTech Connect (OSTI)

The nuclear industries have developed and are trying to create a performance model to improve effectiveness of the processes implemented at nuclear plants in order to enhance performance. Most high performing nuclear stations seek to continually improve the quality of their operations by identifying and closing important performance gaps. Thus, many utilities have implemented performance models adjusted to their plant's configuration and have instituted policies for such models. KHNP is developing a standard performance model to integrate the engineering processes and to improve the inter-relation among processes. The model, called the Standard Equipment Management Model (SEMM), is under development first by focusing on engineering processes and performance improvement processes related to plant equipment used at the site. This model includes performance indicators for each process that can allow evaluating and comparing the process performance among 21 operating units. The model will later be expanded to incorporate cost and management processes. (authors)

Chang, H. S.; Ju, T. Y.; Song, T. Y. [Korea Hydro and Nuclear Power Co., Ltd., 25-1 Jang-dong, Yuseong-gu, Daejeon, 305-343 (Korea, Republic of)

2012-07-01T23:59:59.000Z

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


401

Using a Business Process Model as a Central Organizing Construct for an Undergraduate Weather Forecasting Course  

Science Journals Connector (OSTI)

For the last five years, the author has employed a business process model as a central organizing construct for the senior-level Forecasting Techniques course at Embry- Riddle Aeronautical University's Daytona Beach, Florida, campus. The process model ...

John M. Lanicci

2012-05-01T23:59:59.000Z

402

Fully coupled fluid flow and geomechanics in the study of hydraulic fracturing and post-fracture production.  

E-Print Network [OSTI]

??This work addresses the poroelastic effect on the processes involved in hydraulic fracturing and post-fracture production using a finite element based fully coupled poroelastic model… (more)

Aghighi, Mohammad Ali

2007-01-01T23:59:59.000Z

403

Spatial and temporal coupling models for the discovery of binding events in ChIP-Seq data  

E-Print Network [OSTI]

In this thesis, we will present two methods for identifying binding events in ChIP-Seq data. The motivation of this venture is to propose a complete read generating process under a probabilistic graphical model framework ...

Papachristoudis, Georgios

2010-01-01T23:59:59.000Z

404

THE CARBON-LAND MODEL INTERCOMPARISON PROJECT (C-LAMP): A PROTOTYPE FOR COUPLED BIOSPHERE-ATMOSPHERE MODEL  

E-Print Network [OSTI]

often referred to as Earth System Models (ESMs). While a number of terrestrial and ocean carbon models

Hoffman, Forrest M.

405

Modeling of additive manufacturing process relevant feature in layer based manufacturing process planning  

Science Journals Connector (OSTI)

Compared with general machining processes, additive manufacturing (AM) process has stabler planning route ... approach is applied to the process planning of additive manufacturing in this paper. The concept of “....

Xi-juan Liu ???

2012-04-01T23:59:59.000Z

406

Application of Gaussian Process Modeling to Analysis of Functional Unreliability  

SciTech Connect (OSTI)

This paper applies Gaussian Process (GP) modeling to analysis of the functional unreliability of a “passive system.” GPs have been used widely in many ways [1]. The present application uses a GP for emulation of a system simulation code. Such an emulator can be applied in several distinct ways, discussed below. All applications illustrated in this paper have precedents in the literature; the present paper is an application of GP technology to a problem that was originally analyzed [2] using neural networks (NN), and later [3, 4] by a method called “Alternating Conditional Expectations” (ACE). This exercise enables a multifaceted comparison of both the processes and the results. Given knowledge of the range of possible values of key system variables, one could, in principle, quantify functional unreliability by sampling from their joint probability distribution, and performing a system simulation for each sample to determine whether the function succeeded for that particular setting of the variables. Using previously available system simulation codes, such an approach is generally impractical for a plant-scale problem. It has long been recognized, however, that a well-trained code emulator or surrogate could be used in a sampling process to quantify certain performance metrics, even for plant-scale problems. “Response surfaces” were used for this many years ago. But response surfaces are at their best for smoothly varying functions; in regions of parameter space where key system performance metrics may behave in complex ways, or even exhibit discontinuities, response surfaces are not the best available tool. This consideration was one of several that drove the work in [2]. In the present paper, (1) the original quantification of functional unreliability using NN [2], and later ACE [3], is reprised using GP; (2) additional information provided by the GP about uncertainty in the limit surface, generally unavailable in other representations, is discussed; (3) a simple forensic exercise is performed, analogous to the inverse problem of code calibration, but with an accident management spin: given an observation about containment pressure, what can we say about the system variables? References 1. For an introduction to GPs, see (for example) Gaussian Processes for Machine Learning, C. E. Rasmussen and C. K. I. Williams (MIT, 2006). 2. Reliability Quantification of Advanced Reactor Passive Safety Systems, J. J. Vandenkieboom, PhD Thesis (University of Michigan, 1996). 3. Z. Cui, J. C. Lee, J. J. Vandenkieboom, and R. W. Youngblood, “Unreliability Quantification of a Containment Cooling System through ACE and ANN Algorithms,” Trans. Am. Nucl. Soc. 85, 178 (2001). 4. Risk and Safety Analysis of Nuclear Systems, J. C. Lee and N. J. McCormick (Wiley, 2011). See especially §11.2.4.

R. Youngblood

2014-06-01T23:59:59.000Z

407

Higgs couplings and Naturalness in the littlest Higgs model with T-parity at the LHC and TLEP  

E-Print Network [OSTI]

Motivated by the recent LHC Higgs data and null results in searches for any new physics, we investigate the Higgs couplings and naturalness in the littlest Higgs model with T-parity. By performing the global fit of the latest Higgs data, electroweak precise observables and $R_{b}$ measurements, we find that the scale $f$ can be excluded up to 600 GeV at $2\\sigma$ confidence level. The expected Higgs coupling measurements at the future collider TLEP will improve this lower limit to above 3 TeV. Besides, the top parnter mass $m_{T_{+}}$ can be excluded up to 880 GeV at $2\\sigma$ confidence level. The future HL-LHC can constrain this mass in the region $m_{T_{+}} < 2.2$ TeV corresponding to the fine-tuning being lager than 1%.

Bingfang Yang; Guofa Mi; Ning Liu

2014-09-23T23:59:59.000Z

408

The pressure of strong coupling lattice QCD with heavy quarks, the hadron resonance gas model and the large N limit  

E-Print Network [OSTI]

In this paper we calculate the pressure of pure lattice Yang-Mills theories and lattice QCD with heavy quarks by means of strong coupling expansions. Dynamical fermions are introduced with a hopping parameter expansion, which also allows for the incorporation of finite quark chemical potential. We show that in leading orders the results are in full agreement with expectations from the hadron resonance gas model, thus validating it with a first principles calculation. For pure Yang-Mills theories we obtain the corresponding ideal glueball gas, in QCD with heavy quarks our result equals that of an ideal gas of mesons and baryons. Another finding is that the Yang-Mills pressure in the large N limit is of order $\\sim N^0$ to the calculated orders, when the inverse 't Hooft coupling is used as expansion parameter. This property is expected in the confined phase, where our calculations take place.

Jens Langelage; Owe Philipsen

2010-02-08T23:59:59.000Z

409

To appear in the IEEE Visualization 2002 Proceedings A Model for the Visualization Exploration Process  

E-Print Network [OSTI]

- sualization process is discussed, leading to a general model of the visualization exploration process this end, a model for the visualization exploration process has been developed. Visualization and GraphicsTo appear in the IEEE Visualization 2002 Proceedings A Model for the Visualization Exploration

Jankun-Kelly, T. J.

410

GoPoMoSA: A Goal-Oriented Process Modeling and Simulation Advisor  

E-Print Network [OSTI]

and improvement. This paper presents GoPoMoSA (Goal-oriented Process Modeling and Simulation Advisor), a semi-automatedGoPoMoSA: A Goal-Oriented Process Modeling and Simulation Advisor Xu Bai and LiGuo Huang Dept and Simulation Advisor that semi-automatically discovers suitable Software Process Modeling and Simula- tion

Egyed, Alexander

411

From land use to land cover: Restoring the afforestation signal in a coupled integrated assessment - earth system model and the implications for CMIP5 RCP simulations  

SciTech Connect (OSTI)

Climate projections depend on scenarios of fossil fuel emissions and land use change, and the IPCC AR5 parallel process assumes consistent climate scenarios across Integrated Assessment and Earth System Models (IAMs and ESMs). To facilitate consistency, CMIP5 used a novel land use harmonization to provide ESMs with seamless, 1500-2100 land use trajectories generated by historical data and four IAMs. However, we have identified and partially addressed a major gap in the CMIP5 land coupling design. The CMIP5 Community ESM (CESM) global afforestation is only 22% of RCP4.5 afforestation from 2005 to 2100. Likewise, only 17% of the Global Change Assessment Model’s (GCAM’s) 2040 RCP4.5 afforestation signal, and none of the pasture loss, were transmitted to CESM within a newly integrated model. This is a critical problem because afforestation is necessary for achieving the RCP4.5 climate stabilization. We attempted to rectify this problem by modifying only the ESM component of the integrated model, enabling CESM to simulate 66% of GCAM’s afforestation in 2040, and 94% of GCAM’s pasture loss as grassland and shrubland losses. This additional afforestation increases vegetation carbon gain by 19 PgC and decreases atmospheric CO2 gain by 8 ppmv from 2005 to 2040, implying different climate scenarios between CMIP5 GCAM and CESM. Similar inconsistencies likely exist in other CMIP5 model results, primarily because land cover information is not shared between models, with possible contributions from afforestation exceeding model-specific, potentially viable forest area. Further work to harmonize land cover among models will be required to adequately rectify this problem.

Di Vittorio, Alan; Chini, Louise M.; Bond-Lamberty, Benjamin; Mao, Jiafu; Shi, Xiaoying; Truesdale, John E.; Craig, Anthony P.; Calvin, Katherine V.; Jones, Andrew D.; Collins, William D.; Edmonds, James A.; Hurtt, George; Thornton, Peter E.; Thomson, Allison M.

2014-11-27T23:59:59.000Z

412

Model for a Josephson junction array coupled to a resonant cavity  

SciTech Connect (OSTI)

We describe a simple Hamiltonian for an underdamped Josephson array coupled to a single photon mode in a resonant cavity. Using a Hartree-like mean-field theory, we show that, for any given strength of coupling between the photon field and the Josephson junctions, there is a transition from incoherence to coherence as a function of N, the number of Josephson junctions in the array. Above that value of N, the energy in the photon field is proportional to N{sup 2}, suggestive of coherent emission. These features remain even when the junction parameters have some random variation from junction to junction, as expected in a real array. Both of these features agree with recent experiments by Barbara and co-workers. (c) 2000 The American Physical Society.

Harbaugh, J. Kent [Department of Physics, Ohio State University, 174 West 18th Avenue, Columbus, Ohio 43210 (United States)] [Department of Physics, Ohio State University, 174 West 18th Avenue, Columbus, Ohio 43210 (United States); Stroud, D. [Department of Physics, Ohio State University, 174 West 18th Avenue, Columbus, Ohio 43210 (United States)] [Department of Physics, Ohio State University, 174 West 18th Avenue, Columbus, Ohio 43210 (United States)

2000-06-01T23:59:59.000Z

413

Theoretical modeling of spatial- and temperature-dependent exciton energy in coupled quantum wells  

Science Journals Connector (OSTI)

Motivated by a recent experiment of spatial and temperature-dependent average exciton energy distribution in coupled quantum wells [S. Yang et al., Phys. Rev. B 75, 033311 (2007)], we investigate the nature of the interactions in indirect excitons. Based on the uncertainty principle, along with a temperature and energy-dependent distribution which includes both population and recombination effects, we show that the interplay between an attractive two-body interaction and a repulsive three-body interaction can lead to a natural and good account for the nonmonotonic temperature dependence of the average exciton energy. Moreover, exciton energy maxima are shown to locate at the brightest regions, in agreement with the recent experiments. Our results provide an alternative way for understanding the underlying physics of the exciton dynamics in coupled quantum wells.

C. S. Liu; H. G. Luo; W. C. Wu

2009-09-17T23:59:59.000Z

414

Design of Nanostructured Solar Cells Using Coupled Optical and Electrical Modeling  

E-Print Network [OSTI]

solar   cells:   modeling,   materials  and  device  technology.  Kluwer  Academic  Publishers:  Norwell,  Massachusetts  

Deceglie, Michael G

2014-01-01T23:59:59.000Z

415

Modeling the thermal-hydrologic processes in a large-scale underground heater test in partially saturated fractured tuff  

SciTech Connect (OSTI)

The Drift Scale Test (DST) is being conducted in an underground facility at Yucca Mountain, Nevada, to probe the coupled thermal, hydrological, mechanical, and chemical processes likely to occur in the fractured rock mass around a potential high-level nuclear waste repository. Thermal-hydrological processes in the DST have been simulated using a three-dimensional numerical model. The model incorporates the realistic test configuration and all available site-specific measurements pertaining to the thermal and hydrological properties of the unsaturated fractured tuff of the test block. The modeled predictions were compared to the extensive set of measured data collected in the first year of this 8-year-long test. The mean error between the predictions and measurement at 12 months of heating for over 1600 temperature sensors is about 2 degrees C. Heat-pipe signature in the temperature data, indicating two-phase regions of liquid-vapor counterflow, is seen in both the measurements and simulated results. The redistribution of moisture content in the rock mass (resulting from vaporization and condensation) was probed by periodic air-injection testing and geophysical measurements. Good agreement also occurred between the model predictions and these measurements. The general agreement between predictions from the numerical simulations and the measurements of the thermal test indicates that our fundamental understanding of the coupled thermal-hydrologic processes at Yucca Mountain is sound. However, effects of spatial heterogeneity from discrete fractures that are observed in the temperature data are not matched by simulations from the numerical model, which treat the densely spaced fractures as a continuum.

Birkholzer, J.T.; Tsang, Y.W.

1999-06-24T23:59:59.000Z

416

New Findings from Terrorism Data: Dirichlet Process Random Effects Models for Latent Groups  

E-Print Network [OSTI]

New Findings from Terrorism Data: Dirichlet Process Random Effects Models for Latent Groups Minjung, and then we use the model to analyze terrorism data. We see that the richer Dirichlet process random effects, empirical studies of terrorism, logistic regression, gen- eralized linear mixed models, hierarchical models

Gill, Jeff

417

Chapter 4: Refrigeration Process Control: Simulation Model 64 44.. RREEFFRRIIGGEERRAATTIIOONN PPRROOCCEESSSS  

E-Print Network [OSTI]

Chapter 4: Refrigeration Process Control: Simulation Model 64 44.. RREEFFRRIIGGEERRAATTIIOONN of the simulation model for the two-stage refrigeration system is presented. The model is based on the mathematical, it is #12;Chapter 4: Refrigeration Process Control: Simulation Model 65 translated into FORTRAN or C

Skogestad, Sigurd

418

Transient Response of the Hadley Centre Coupled Ocean-Atmosphere Model to Increasing Carbon Dioxide. Part 1: Control Climate and Flux Adjustment  

Science Journals Connector (OSTI)

This paper describes the initialization of an experiment to study the time-dependent response of a high-resolution global coupled ocean-atmosphere general circulation model to a gradual increase in carbon dioxide. The stability of the control ...

J. M. Murphy

1995-01-01T23:59:59.000Z

419

Improving an Accuracy of ANN-Based Mesoscale-Microscale Coupling Model by Data Categorization: With Application to Wind Forecast for Offshore and Complex Terrain Onshore Wind Farms  

Science Journals Connector (OSTI)

The ANN-based mesoscale-microscale coupling model forecasts wind speed and wind direction with high accuracy for wind parks located in complex terrain onshore, yet some weather regimes remains unresolved and f...

Alla Sapronova; Catherine Meissner…

2014-01-01T23:59:59.000Z

420

The Dynamical Core, Physical Parameterizations, and Basic Simulation Characteristics of the Atmospheric Component AM3 of the GFDL Global Coupled Model CM3  

Science Journals Connector (OSTI)

The Geophysical Fluid Dynamics Laboratory (GFDL) has developed a coupled general circulation model (CM3) for the atmosphere, oceans, land, and sea ice. The goal of CM3 is to address emerging issues in climate change, including aerosol–cloud ...

Leo J. Donner; Bruce L. Wyman; Richard S. Hemler; Larry W. Horowitz; Yi Ming; Ming Zhao; Jean-Christophe Golaz; Paul Ginoux; S.-J. Lin; M. Daniel Schwarzkopf; John Austin; Ghassan Alaka; William F. Cooke; Thomas L. Delworth; Stuart M. Freidenreich; C. T. Gordon; Stephen M. Griffies; Isaac M. Held; William J. Hurlin; Stephen A. Klein; Thomas R. Knutson; Amy R. Langenhorst; Hyun-Chul Lee; Yanluan Lin; Brian I. Magi; Sergey L. Malyshev; P. C. D. Milly; Vaishali Naik; Mary J. Nath; Robert Pincus; Jeffrey J. Ploshay; V. Ramaswamy; Charles J. Seman; Elena Shevliakova; Joseph J. Sirutis; William F. Stern; Ronald J. Stouffer; R. John Wilson; Michael Winton; Andrew T. Wittenberg; Fanrong Zeng

2011-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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421

A Mechanistic Study of the Influence of Proton Transfer Processes on the Behavior of Thiol/Disulfide Redox Couples  

Science Journals Connector (OSTI)

3 This facilitation of the DMcT redox process comprises an important finding, because, even though the thermodynamics of thiol/disulfide redox processes are quite attractive from the perspective of lithium cathode materials, their kinetics are typically very slow at room temperature. ... Because these elementary steps are thermodynamically interrelated, their equilibrium constants (for chemical reactions) and E° values (for electrochemical reactions) cannot be varied independently, providing some constraints on the number of independent variables in the simulation. ...

Eiichi Shouji; Daniel A. Buttry

1999-03-06T23:59:59.000Z

422

Modeling of underwater noise from pile driving using coupled finite element and parabolic equation model with improved parabolic equation starting field  

Science Journals Connector (OSTI)

An offshore wind farm will be constructed in the Yellow Sea west of Korean Peninsula where there are extensive fishing activity and numerous fishery farms. To study the effect of underwater piling noise on fishing and marine lives we model the pile driving noise propagation using coupled FE and PE model. The near-field noise is computed by FE model considering detailed specifications of the pile driving system. We apply 2D axis-symmetric geometry and utilize acoustic structure interaction analysis in the frequency domain. The FE results are used to compose the starting field for PE model where appropriate range selection is an important factor to cover most of the contributing ray paths. Extrapolation technique to compensate the lack of FE data and the numerical filtering method to smooth the FE result are discussed. In the far-field the noise propagation is modeled by the split step Pade PE algorithm. The improved PE starting field seems to give refined result than previous coupled model.

Jungyong Park

2013-01-01T23:59:59.000Z

423

Development and Validation of a Partially Coupled Two-equation Soot Model for Industrial Applications.  

E-Print Network [OSTI]

??There are several reasons for reducing particulate formation as a result of combustion processes and to date, a number of approaches have been proposed to… (more)

Khalilian, Kaveh

2013-01-01T23:59:59.000Z

424

Tropical Water Vapor and Cloud Feedbacks in Climate Models: A Further Assessment Using Coupled Simulations  

Science Journals Connector (OSTI)

By comparing the response of clouds and water vapor to ENSO forcing in nature with that in Atmospheric Model Intercomparison Project (AMIP) simulations by some leading climate models, an earlier evaluation of tropical cloud and water vapor ...

De-Zheng Sun; Yongqiang Yu; Tao Zhang

2009-03-01T23:59:59.000Z

425

The Southern Ocean in the Coupled Model Intercomparison Project phase 5  

Science Journals Connector (OSTI)

...atmosphere and ocean (although the ocean remains too coarse to permit mesoscale eddies), a larger proportion of full Earth system models (ESMs) resolving biogeochemical cycles, the inclusion of atmospheric ozone in all models and more complete atmospheric...

2014-01-01T23:59:59.000Z

426

The long-term change of El Niño Southern Oscillation in an ensemble reanalysis and climate coupled models  

E-Print Network [OSTI]

THE LONG-TERM CHANGE OF EL NI?O SOUTHERN OSCILLATION IN AN ENSEMBLE REANALYSIS AND CLIMATE COUPLED MODELS A Dissertation by CHUNXUE YANG Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment...ESM1-M Norwegian Climate Centre 3 F19, L26 gx1v6L53 Bentsen et al. [2012] 20 CHAPTER III RESULTS Ensemble Reanalysis Ensemble Statistics El Ni?o/Southern Oscillation (ENSO) has significant impact on world economics, society...

Yang, Chunxue 1984-

2012-12-06T23:59:59.000Z

427

Dynamically Coupled 3D Pollutant Dispersion Model for Assessing Produced Water Discharges in the Canadian Offshore Area  

Science Journals Connector (OSTI)

Dynamically Coupled 3D Pollutant Dispersion Model for Assessing Produced Water Discharges in the Canadian Offshore Area ... The collected samples of produced water and seawater were analyzed by the COOGER (Centre for Offshore Oil and Gas Environmental Research) at the Fisheries and Oceans Canada, Environmental Engineering labrotary at the Concordia University, and the Trace Analysis Facility (TAF) at the University of Regina. ... In Offshore Oil and Gas Environmental Effects Monitoring Approaches and Technologies; Armsworthy, S. L.; Cranford, P. J.; Lee, K., Eds.; Battelle Memorial Institute: Columbus, OH 2005; pp 319– 342. ...

Lin Zhao; Zhi Chen; Kenneth Lee

2012-12-26T23:59:59.000Z

428

Kaon Condensation in a Neutron Star under Strong Magnetic Fields by Using the Modified Quark-meson Coupling Model  

E-Print Network [OSTI]

We have considered the antikaon condensation in a neutron star in the presence of strong magnetic fields by using the modified quark-meson coupling (MQMC) model. The structure of the neutron star is investigated with various magnetic fields and different kaon optical potentials, and the effects of the magnetic fields for kaon condensation is discussed. When employing strong magnetic fields inside a neutron star with hyperons and kaon condensation, the magnetic fields can cause the equation of state to be stiff; thus, a large maximum mass of the neutron star can be obtained.

C. Y. Ryu; S. W. Hong

2011-08-27T23:59:59.000Z

429

Advanced modeling of planarization processes for integrated circuit fabrication  

E-Print Network [OSTI]

Planarization processes are a key enabling technology for continued performance and density improvements in integrated circuits (ICs). Dielectric material planarization is widely used in front-end-of-line (FEOL) processing ...

Fan, Wei, Ph. D. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

430

Numerical modeling of a wing skin peen forming process  

Science Journals Connector (OSTI)

For many years shot peering has been used to provide fatigue resistance and form to airplane wing skins at the Boeing Commercial Airplane Company. In this process, ... to replicate the shot peening process used a...

R. D. VanLuchene; E. J. Cramer

1996-12-01T23:59:59.000Z

431

Multiphase CFD-based models for chemical looping combustion process: Fuel reactor modeling  

SciTech Connect (OSTI)

Chemical looping combustion (CLC) is a flameless two-step fuel combustion that produces a pure CO2 stream, ready for compression and sequestration. The process is composed of two interconnected fluidized bed reactors. The air reactor which is a conventional circulating fluidized bed and the fuel reactor which is a bubbling fluidized bed. The basic principle is to avoid the direct contact of air and fuel during the combustion by introducing a highly-reactive metal particle, referred to as oxygen carrier, to transport oxygen from the air to the fuel. In the process, the products from combustion are kept separated from the rest of the flue gases namely nitrogen and excess oxygen. This process eliminates the energy intensive step to separate the CO2 from nitrogen-rich flue gas that reduce the thermal efficiency. Fundamental knowledge of multiphase reactive fluid dynamic behavior of the gas–solid flow is essential for the optimization and operation of a chemical looping combustor. Our recent thorough literature review shows that multiphase CFD-based models have not been adapted to chemical looping combustion processes in the open literature. In this study, we have developed the reaction kinetics model of the fuel reactor and implemented the kinetic model into a multiphase hydrodynamic model, MFIX, developed earlier at the National Energy Technology Laboratory. Simulated fuel reactor flows revealed high weight fraction of unburned methane fuel in the flue gas along with CO2 and H2O. This behavior implies high fuel loss at the exit of the reactor and indicates the necessity to increase the residence time, say by decreasing the fuel flow rate, or to recirculate the unburned methane after condensing and removing CO2.

Jung, Jonghwun (ANL); Gamwo, I.K.

2008-04-21T23:59:59.000Z

432

PARAMETERIZATION AND TESTING OF A COUPLED MODEL OF PHOTOSYNTHESIS-STOMATAL CONDUCTANCE FOR GREENHOUSE ROSE  

E-Print Network [OSTI]

FOR GREENHOUSE ROSE CROP Soo-Hyung Kim and J. Heinrich Lieth Department of Environmental Horticulture University for combinations of relative humidity, light, and temperature. The model was calibrated and validated for the cut assimilation is a core of those crop simulation models. Photosynthesis models in horticulture have been

Lieth, J. Heinrich

433

NUMERICAL EXPERIMENTS USING MESONH/FOREFIRE COUPLED ATMOSPHERIC-FIRE MODEL  

E-Print Network [OSTI]

model inputting the wind fields and outputting heat and vapour fluxes to the atmospheric model. Fore mesh. Another originality of the approach is the fire rate of spread model that integrates wind effect of has been developed to add locale atmosphere interaction to the family of fire area simulators

Boyer, Edmond

434

Multi-scale process and supply chain modelling: from lignocellulosic feedstock to process and products  

Science Journals Connector (OSTI)

...process net profit pyrolysis for corn stover net profit = F(transportation...pressure) enzymatic hydrolysis for energy crops net profit = F(transportation...hybrid process for a mixture of corn stover, energy crops and forest residue net profit...

2011-01-01T23:59:59.000Z

435

Cathodic reduction of hexavalent chromium coupled with electricity generation achieved by reverse-electrodialysis processes using salinity gradients  

Science Journals Connector (OSTI)

Abstract A new approach for the simultaneous generation of electric energy and the treatment of waters contaminated by recalcitrant pollutants using salinity gradients was proposed. Reverse electrodialysis allows for the generation of electric energy from salinity gradients. Indeed, the utilization of different salt concentrations gives a potential difference between the electrodes which allows the generation of electric energy by using suitable electrolytes and an external circuit. The simultaneous generation of electric energy and the treatment of waters contaminated by Cr(VI) was successfully achieved for the first time by reverse electrodialysis processes using salinity gradients and proper redox processes. The effect on the process of many operative parameters, such as the extent of the salinity gradient, the number of membrane pairs in the stack, the initial concentration of Cr(VI), the concentration of the supporting electrolyte and the flow rates of the solutions fed in the stack, was also investigated.

O. Scialdone; A. D’Angelo; E. De Lumè; A. Galia

2014-01-01T23:59:59.000Z

436

The El Nino-Southern Oscillation in the second Hadley Centre coupled model and its response to greenhouse warming  

SciTech Connect (OSTI)

This paper describes El Nino-Southern Oscillation (ENSO) interannual variability simulated in the second Handley Centre coupled model under control and greenhouse warming scenarios. The model produces a very reasonable simulation of ENSO in the control experiment--reproducing the amplitude, spectral characteristics, and phase locking to the annual cycle that are observed in nature. The mechanism for the model ENSO is shown to be a mixed SST-ocean dynamics mode that can be interpreted in terms of the ocean recharge paradigm of Jin. In experiments with increased levels of greenhouse gases, no statistically significant changes in ENSO are seen until these levels approach four times preindustrial values. In these experiments, the model ENSO has an approximately 20% larger amplitude, a frequency that is approximately double that of the current ENSO (implying more frequent El Ninos and La Ninas), and phase locks to the annual cycle at a different time of year. It is shown that the increase in the vertical gradient of temperature in the thermocline region, associated with the model's response to increased greenhouse gases, is responsible for the increase in the amplitude of ENSO, while the increase in meridional temperature gradients on either side of the equator, again associated with the models response to increasing greenhouse gases, is responsible for the increased frequency of ENSO events.

Collins, M.

2000-04-01T23:59:59.000Z

437

Modeling the coupled effects of heat transfer. thermochemistry, and kinetics during biomass torrefaction  

E-Print Network [OSTI]

Torrefaction is a thermal pretreatment process which improves the energy density, storage, grinding, and handling characteristics of raw biomass. Research efforts to date have focused on empirical measurements of the fuel ...

Bates, Richard Burton

2012-01-01T23:59:59.000Z

438

A turbulent transport network model in MULTIFLUX coupled with TOUGH2  

E-Print Network [OSTI]

Near-Field TH Processes at Yucca Mountain. Proceedings, 11thEmplacement Tunnels at Yucca Mountain. Journal of Nuclearand condensation. Yucca Mountain Project Report, MDL-EBS-MD-

Danko, G.

2012-01-01T23:59:59.000Z

439

Emerging disease dynamics in a model coupling within-host and ...  

E-Print Network [OSTI]

Aug 2, 2014 ... Immunological models consider the within-host dynamics independent of the interactions between hosts (e.g., De Leenheer and Smith, 2003;.

Xiuli Cen

2014-08-27T23:59:59.000Z

440

Multi-Modal Modeling, Analysis and Validation of Open Source Software Requirements Processes  

E-Print Network [OSTI]

model of the OSS requirements process requires multiple, comparative project case studies, so our1 Multi-Modal Modeling, Analysis and Validation of Open Source Software Requirements Processes Walt@uci.edu Abstract Understanding the context, structure, activities, and content of software development processes

Scacchi, Walt

Note: This page contains sample records for the topic "modeling coupled processes" 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

Models for Optimization of Energy Consumption of Pumps in a Wastewater Processing Plant  

E-Print Network [OSTI]

Models for Optimization of Energy Consumption of Pumps in a Wastewater Processing Plant Zijun Zhang in the wastewater preliminary treatment process is discussed. Data- mining algorithms are utilized to develop pump performance models based on industrial data collected at a municipal wastewater processing plant

Kusiak, Andrew

442

Development of Efficient Flowsheet and Transient Modeling for Nuclear Heat Coupled Sulfur Iodine Cyclefor Hydrogen Production  

SciTech Connect (OSTI)

The realization of the hydrogen as an energy carrier for future power sources relies on a practical method of producing hydrogen in large scale with no emission of green house gases. Hydrogen is an energy carrier which can be produced by a thermochemical water splitting process. The Sulfur-Iodine (SI) process is an example of a water splitting method using iodine and sulfur as recycling agents.

Shripad T. Revankar; Nicholas R. Brown; Cheikhou Kane; Seungmin Oh

2010-05-01T23:59:59.000Z

443

Applicability of Related Data, Algorithms, and Models to the Simulation of Ground-Coupled Residential Hot Water Piping in California  

SciTech Connect (OSTI)

Residential water heating is an important consideration in California?s building energy efficiency standard. Explicit treatment of ground-coupled hot water piping is one of several planned improvements to the standard. The properties of water, piping, insulation, backfill materials, concrete slabs, and soil, their interactions, and their variations with temperature and over time are important considerations in the required supporting analysis. Heat transfer algorithms and models devised for generalized, hot water distribution system, ground-source heat pump and ground heat exchanger, nuclear waste repository, buried oil pipeline, and underground electricity transmission cable applications can be adapted to the simulation of under-slab water piping. A numerical model that permits detailed examination of and broad variations in many inputs while employing a technique to conserve computer run time is recommended.

Warner, J.L.; Lutz, J.D.

2006-01-01T23:59:59.000Z

444

Multi-scale modeling of laser cladding process .  

E-Print Network [OSTI]

??"Laser cladding is an additive manufacturing process in which a laser generates a melt-pool on the substrate material while a second material in a powder… (more)

Cao, Yunfeng, 1977-

2006-01-01T23:59:59.000Z

445

Coupling of ecological and water quality models for improved water resource and fish management  

E-Print Network [OSTI]

values of primary producers and other groups to predict fish biomass. Linking the two models will provide the means of going up the food chain by trophic levels. The Chesapeake Bay was chosen as the study site since both models are in use there. Before...

Tillman, Dorothy Hamlin

2009-05-15T23:59:59.000Z

446

A mesoscopic approach to modeling and simulation of logistics processes  

Science Journals Connector (OSTI)

Simulation models are important for planing, implementing and operating logistics systems since they can depict their dynamic system behavior. In the field of logistics, discrete-event models are widely used. Their creation and computation is often very ...

Tobias Reggelin; Juri Tolujew

2011-12-01T23:59:59.000Z

447

Modeling Disease Incidence Data with Spatial and Spatio-Temporal Dirichlet Process Mixtures  

E-Print Network [OSTI]

Modeling Disease Incidence Data with Spatial and Spatio-Temporal Dirichlet Process Mixtures approaches to analyze such data. We develop a hierarchical specification using spatial random effects modeled. Key words: Areal unit spatial data; Dirichlet process mixture models; Disease mapping; Dy- namic

Wolpert, Robert L

448

Sensitivity Analysis of Optimal Operation of an Activated Sludge Process Model for Economic Controlled Variable Selection  

E-Print Network [OSTI]

Sensitivity Analysis of Optimal Operation of an Activated Sludge Process Model for Economic operation conducted on an activated sludge process model based on the test-bed benchmark simulation model no structure that leads to optimal economic operation, while promptly rejecting disturbances at lower layers

Skogestad, Sigurd

449

Discovering Concurrent Process Models in Data: A Rough Set Approach  

Science Journals Connector (OSTI)

The aim of the lecture is to provide a survey of state of the art related to a research direction concerning relationships between rough set theory and concurrency in the context of process mining in data. The main goal of this review is the general ... Keywords: Knowledge discovery, Petri nets, concurrent systems, data mining, process mining, rough sets

Zbigniew Suraj

2009-12-01T23:59:59.000Z

450

Model-Driven Process Configuration of Enterprise Systems*  

E-Print Network [OSTI]

by Nordsieck who argued in 1934 that the structure of a company should be process-oriented [Nord34, p. 77] and compared the structure of a company to a stream, because it is an "uninterrupted value chain" [translated from Nord72]. Based on these ideas, Business Process Reengineering (BPR) be- came a popular management

van der Aalst, Wil

451

Review of Optimization Models for Integrated Process Water Networks and their Application to Biofuel Processes  

E-Print Network [OSTI]

to Biofuel Processes Ignacio E. Grossmann1, Mariano Mart�n2 and Linlin Yang1 1Department Chemical Engineering of these techniques to biofuel plants, which are known to consume large amounts of water. Introduction. Although water stress [1]. Since chemical, petroleum, and especially biofuel processes consume significant amounts

Grossmann, Ignacio E.

452

A reduced-form statistical climate model suitable for coupling with economic emissions projections  

E-Print Network [OSTI]

In this work, we use models based on past data and scientific analysis to determine possible future states of the environment. We attempt to improve the equations for temperature and greenhouse gas concentration used in ...

Rabin, Gregory S

2007-01-01T23:59:59.000Z

453

Parameter estimation of coupled water and energy balance models based on stationary constraints of surface states  

E-Print Network [OSTI]

[1] We use a conditional averaging approach to estimate the parameters of a land surface water and energy balance model and then use the estimated parameters to partition net radiation into latent, sensible, and ground ...

Sun, Jian

454

A coupled-physics model for the vanadium oxygen fuel cell  

Science Journals Connector (OSTI)

Abstract A stationary two-dimensional model for the vanadium oxygen fuel cell is developed. The model consists of a single cell with two membranes, set up as of two half-cells and an intermediate chamber. The transport and balance of mass, momentum and charge are linked to the electrochemical reaction kinetics of the vanadium species and oxygen. The kinetic model for the cathode half-cell is extended by an empirical logistic function to describe the transient behavior of the half-cell. Additionally, experiments are conducted on a single vanadium oxygen fuel cell with 40 cm2 active membrane area. The experimental results are used to validate the simulation data. The effects of constant current discharging, polarization behavior and different flow rates on the cathode overpotential are studied by means of this model.

F.T. Wandschneider; M. Küttinger; J. Noack; P. Fischer; K. Pinkwart; J. Tübke; H. Nirschl

2014-01-01T23:59:59.000Z

455

SciTech Connect: Progress in coupling Land Ice and Ocean Models...  

Office of Scientific and Technical Information (OSTI)

AC52-06NA25396 Resource Type: Conference Resource Relation: Conference: Community Earth System Model Land Ice Working Group Meeting ; 2013-02-14 - 2013-02-15 ; Boulder,...

456

A Continuum Coupled Moisture-mechanical Constitutive Model for Asphalt Concrete  

E-Print Network [OSTI]

constitutive relationships are implemented in the Pavement Analysis using Nonlinear Damage Approach (PANDA) finite element (FE) package to model the moisture damage effect on the complex environmental-mechanical response of asphalt concrete. The developed...

Shakiba, Maryam

2013-12-09T23:59:59.000Z

457

Improving parameterization of scalar transport through vegetation in a coupled ecosystem-atmosphere model  

E-Print Network [OSTI]

Several regional-scale ecosystem models currently parameterize subcanopy scalar transport using a rough-wall boundary eddy diffusivity formulation. This formulation predicts unreasonably high soil evaporation beneath tall, ...

Link, Percy Anne

2008-01-01T23:59:59.000Z

458

Scattering of plane evanescent waves by buried cylinders: Modeling the coupling to guided waves and resonances  

Science Journals Connector (OSTI)

The coupling of sound to buried targets can be associated with acoustic evanescent waves when the sea bottom is smooth. To understand the excitation of guided waves on buried fluid cylinders and shells by acoustic evanescent waves and the associated target resonances the two?dimensional partial wave series for the scattering is found for normal incidence in an unbounded medium. The shell formulation uses the simplifications of thin?shell dynamics. The expansion of the incident wave becomes a double summation with products of modified and ordinary Bessel functions [P. L. Marston J. Acoust. Soc. Am. 111 2378 (2002)]. Unlike the case of an ordinary incident wave the counterpropagating partial waves of the same angular order have unequal magnitudes when the incident wave is evanescent. This is a consequence of the exponential dependence of the incident wave amplitude on depth. Some consequences of this imbalance of partial?wave amplitudes are given by modifying previous ray theory for the scattering [P. L. Marston and N. H. Sun J. Acoust. Soc. Am. 97 777–783 (1995)]. The exponential dependence of the scattering on the location of a scatterer was previously demonstrated in air [T. J. Matula and P. L. Marston J. Acoust. Soc. Am. 93 1192–1195 (1993)].

2003-01-01T23:59:59.000Z

459

Quality Guidelines for Energy System Studies Process Modeling...  

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

property method. The NRTL method more accurately predicts the solubility of chlorides in water. The sulfur recovery unit and CO 2 capture process use the PENG-ROB equation of...

460

Computational Modeling of Relevant Automotive Rotary Spray Painting Process  

Science Journals Connector (OSTI)

During the automotive spray painting process, metallic car shells are conveyed at ... specified constant rectilinear speed through the booth. Robot-assisted rotary atomizers spray the car shell ... path particula...

Abraham J. Salazar

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling coupled processes" 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

Enzymatic corn wet milling: engineering process and cost model  

Science Journals Connector (OSTI)

Enzymatic corn wet milling (E-milling) is a process derived from conventional wet milling for the recovery and purification of starch ... the total starch production in USA by conventional wet milling equaled 23 ...

Edna C Ramírez; David B Johnston; Andrew J McAloon…

2009-01-01T23:59:59.000Z

462

Discovering Concurrent Process Models in Data: A Rough Set Approach  

Science Journals Connector (OSTI)

The aim of the lecture is to provide a survey of state of the art related to a research direction concerning relationships between rough set theory and concurrency in the context of process mining in data. The...

Zbigniew Suraj

2009-01-01T23:59:59.000Z

463

Process Simulation, Modeling & Design for Soybean Oil Extraction Using Liquid Propane.  

E-Print Network [OSTI]

??This study investigates the use of liquid propane for soybean oil extraction and the use of commercial software for process modeling and simulation. Soybean oil… (more)

Patrachari, Anirudh Ramanujan

2008-01-01T23:59:59.000Z

464

Multi-scale process and supply chain modelling: from lignocellulosic feedstock to process and products  

Science Journals Connector (OSTI)

...immediately after designing an infrastructure network and considers a fixed infrastructure over a certain time period...classifications of supply chain. infrastructure network design supply...temperature and pressure) hybrid process for a mixture...

2011-01-01T23:59:59.000Z

465

A Two Term Truncation of the Multiple Ising Model Coupled to 2d Gravity  

E-Print Network [OSTI]

We consider a model of p independent Ising spins on a dynamical planar phi-cubed graph. Truncating the free energy to two terms yields an exactly solvable model that has a third order phase transition from a pure gravity region (gamma=-1/2) to a tree-like region (gamma=1/2), with gamma=1/3 on the critical line. We are able to make an order of magnitude estimate of the value of p above which there exists a branched polymer (ie tree-like) phase in the full model, that is, p is approximately 13-23, which corresponds to a central charge c of about 6-12.

Martin G. Harris

1995-02-06T23:59:59.000Z

466

A dual-porosity reservoir model with a nonlinear coupling term  

SciTech Connect (OSTI)

Since their introduction by Barenblatt et al. (1960), double-porosity models have been widely used for simulating flow in fractured reservoirs, such as geothermal reservoirs. In a dual-porosity system, the matrix blocks provide most of the storage of the reservoir, whereas the fractures provide the global transmissivity. Initially, most work on dual-porosity models emphasized the development of analytical solutions to idealized reservoir problems. Increasingly, the dual-porosity approach is being implemented by numerical reservoir simulators. Accurate numerical simulation of a dual-porosity problem often requires a prohibitively large number of computational cells in order to resolve the transient pressure gradients in the matrix blocks. We discuss a new dual-porosity model that utilizes a nonlinear differential equation to approximate the fracture/matrix interactions, When implemented into a numerical simulator, it eliminates the need to discretize the matrix blocks, and thereby allows more efficient simulation of reservoir problems.

Zimmerman, R.W.; Chen, G.; Hadgu, T.; Bodvarsson, G.S.

1992-09-01T23:59:59.000Z

467

Mathematical modelling of maintained systems using point processes  

Science Journals Connector (OSTI)

......various models based on the sum of residual squares. An inherently different...failure times in days of two gas compressors at Norsk Hydro in...obtained from a hydroelectric turbine of the B.C.Hydro-Power...alert model to the data set of a gas generator. They found that......

A. Syamsundar; V. N. A. Naikan

2009-07-01T23:59:59.000Z

468

Gaussian Process Modeling and Computation in Engineering Applications  

E-Print Network [OSTI]

; and predictive modeling for large datasets. First, we develop a spatial-temporal model for local wind fields in a wind farm with more than 200 wind turbines. Our framework utilizes the correlation among the derivatives of wind speeds to find a neighborhood...

Pourhabib, Arash

2014-07-08T23:59:59.000Z

469

Tropical Cyclone Simulation and Response to CO2 Doubling in the GFDL CM2.5 High-Resolution Coupled Climate Model  

Science Journals Connector (OSTI)

Global tropical cyclone (TC) activity is simulated by the Geophysical Fluid Dynamics Laboratory (GFDL) Climate Model, version 2.5 (CM2.5), which is a fully coupled global climate model with a horizontal resolution of about 50 km for the atmosphere ...

Hyeong-Seog Kim; Gabriel A. Vecchi; Thomas R. Knutson; Whit G. Anderson; Thomas L. Delworth; Anthony Rosati; Fanrong Zeng; Ming Zhao

2014-11-01T23:59:59.000Z

470

GFDL’s ESM2 Global Coupled Climate–Carbon Earth System Models. Part II: Carbon System Formulation and Baseline Simulation Characteristics  

Science Journals Connector (OSTI)

The authors describe carbon system formulation and simulation characteristics of two new global coupled carbon–climate Earth System Models (ESM), ESM2M and ESM2G. These models demonstrate good climate fidelity as described in part I of this study ...

John P. Dunne; Jasmin G. John; Elena Shevliakova; Ronald J. Stouffer; John P. Krasting; Sergey L. Malyshev; P. C. D. Milly; Lori T. Sentman; Alistair J. Adcroft; William Cooke; Krista A. Dunne; Stephen M. Griffies; Robert W. Hallberg; Matthew J. Harrison; Hiram Levy; Andrew T. Wittenberg; Peter J. Phillips; Niki Zadeh

2013-04-01T23:59:59.000Z

471

Emergence of multiple critical points in the NJL model with vector coupling  

SciTech Connect (OSTI)

In this work, we discuss the main theoretical consequences related to the consideration of a vector-isoscalar contribution term to the standard SU(2) NJL Model. We also present results concerning the QCD critical point determination and its dependence on the quark current mass.

Denke, R.; Macias, J. C.; Pinto, M. B. [Departamento de Fisica - Universidade Federal de Santa Catarina, Florianopolis (Brazil)

2013-03-25T23:59:59.000Z

472

Bond Graph Model of a Vertical U-Tube Steam Condenser Coupled with a Heat Exchanger  

E-Print Network [OSTI]

level. Steam condensers are integral part of any nuclear and thermal power plant utilising steam A simulation model for a vertical U-tube steam condenser in which the condensate is stored at the bottom well and thus the bottom well acts as a heat exchanger. The storage of hydraulic and thermal energies

Paris-Sud XI, Université de

473

Transient fluid and heat flow modeling in coupled wellbore/reservoir systems  

E-Print Network [OSTI]

showing cleanup period.......................................................... 68 Figure 5.21 Geothermal gradient and sea water temperature profile............................. 68 Figure 5.22 Mimicking oil production rate input... into this category. 5 Miller (1980) developed one of the earliest transient wellbore simulators, which accounts for changes in geothermal-fluid energy while flowing up the wellbore. In this model, mass and momentum equations are combined...

Izgec, Bulent

2009-05-15T23:59:59.000Z

474

Efficient Macro-Micro Scale Coupled Modeling of Batteries Venkat R. Subramanian,*,z  

E-Print Network [OSTI]

in the macroscale x and solid-state diffusion in the microscale inside the particle r . Battery models typically concentration, electrolyte potential, solid-state potential, and solid-state concentra- tion in the porous nonlinear PDEs in x,t in the porous electrode.1-4 In addition, solid-state diffusion should be solved

Subramanian, Venkat

475

A COMPUTATIONAL MODEL OF COUPLED HEAT AND MOISTURE TRANSFER WITH PHASE CHANGE  

E-Print Network [OSTI]

, The University of Greenwich, London, UK Mark C. Leaper Formerly The Wolfson Centre for Bulk Solids Handling Technology, The University of Greenwich, London, UK As part of a comprehensive effort to predict=cycling. The resulting model partial differential equations were solved using finite-volume procedures in the context

Christakis, Nikolaos

476

Stimulation at Desert Peak -modeling with the coupled THM code FEHM  

SciTech Connect (OSTI)

Numerical modeling of the 2011 shear stimulation at the Desert Peak well 27-15. This submission contains the FEHM executable code for a 64-bit PC Windows-7 machine, and the input and output files for the results presented in the included paper from ARMA-213 meeting.

sharad kelkar

2013-04-30T23:59:59.000Z

477

Syngas production in a novel methane dry reformer by utilizing of tri-reforming process for energy supplying: Modeling and simulation  

Science Journals Connector (OSTI)

Abstract In this study, tri-reforming process has been utilized as an energy source for driving highly endothermic process of methane dry reforming process in a multi-tubular recuperative thermally coupled reactor (TCTDR). 184 two-concentric-tubes have been proposed for this configuration. Outer tube sides of the two-concentric-tubes have been considered for the tri-reforming reactions while dry reforming process takes place in inner tube sides. Simulation results of co-current mode have been compared with corresponding predictions of thermally coupled tri- and steam reformer (TCTSR); in which the tri-reforming process has been coupled with steam reforming of methane in same conditions. A mathematical heterogeneous model has been applied to simulate both dry and tri-reforming sides of the TCTDR. Results showed that methane conversion at the output of dry and tri-reforming sides reached to 63% and 93%, respectively. Also, molar flow rate of syngas at the output of DR side of TCTDR reached to 7464 kmol h?1 in comparison to 3912 kmol h?1 for SR side of TCTSR.

Mehdi Farniaei; Mohsen Abbasi; Hamid Rahnama; Mohammad Reza Rahimpour; Alireza Shariati

2014-01-01T23:59:59.000Z

478

A new BML-based RANS modelling for the description of gas turbine typical combustion processes  

Science Journals Connector (OSTI)

The work is concentrated on the formulation and validation of integral models within RANS framework for the numerical prediction of the premixed and partially premixed flames occurring in gas turbine combustors. The premixed combustion modelling is based on the BML approach coupled to the mixing transport providing variable equivalence ratio. Chemistry is described by means of ILDM model solving transport equations for reaction progress variables conditioned on the flame front. Multivariate presumed PDF model is used for the turbulence-chemistry interaction treatment. Turbulence is modelled using the second moment closure (SMC) and the standard ?-? model as well. The influence of non-gradient turbulent transport is investigated comparing the gradient diffusion closure and the solution of the scalar flux transport equations. Different model combinations are assessed simulating several premixed and partially premixed flame configurations and comparing results to the experimental data. The proposed model provides good predictions particularly in combination with SMC.

A. Maltsev; A. Sadiki; J. Janicka

2004-01-01T23:59:59.000Z

479

Bayesian Modeling and Analysis for Gradients in Spatiotemporal Processes  

E-Print Network [OSTI]

form for total air pollution measurements. Computationalanalysis of the California air pollution data, supplying theair quality warnings, public health officials rely on statistical models to predict each day’s pollution

Quick, Harrison; Banerjee, Sudipto; Carlin, Bradley P.

2015-01-01T23:59:59.000Z

480

Concurrent multiscale modelling of atomistic and hydrodynamic processes in liquids  

Science Journals Connector (OSTI)

...Modelling, Moscow Institute of Nuclear Safety, , 113191 Moscow, Russia One contribution...GROMOS for the peptide. The GROMACS software package was used for integrating the...mechanism associated with downstream radiation in subsonic jets. J. Fluid Mech. 710...

2014-01-01T23:59:59.000Z