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1

Comprehensive chemical kinetic modeling of the oxidation of C8 and larger n-alkanes and 2-methylalkanes  

SciTech Connect

Conventional petroleum jet and diesel fuels, as well as alternative Fischer-Tropsch (FT) fuels and hydrotreated renewable jet (HRJ) fuels, contain high molecular weight lightly branched alkanes (i.e., methylalkanes) and straight chain alkanes (n-alkanes). Improving the combustion of these fuels in practical applications requires a fundamental understanding of large hydrocarbon combustion chemistry. This research project presents a detailed and reduced chemical kinetic mechanism for singly methylated iso-alkanes (i.e., 2-methylalkanes) ranging from C{sub 8} to C{sub 20}. The mechanism also includes an updated version of our previously published C{sub 8} to C{sub 16} n-alkanes model. The complete detailed mechanism contains approximately 7,200 species 31,400 reactions. The proposed model is validated against new experimental data from a variety of fundamental combustion devices including premixed and nonpremixed flames, perfectly stirred reactors and shock tubes. This new model is used to show how the presence of a methyl branch affects important combustion properties such as laminar flame propagation, ignition, and species formation.

Sarathy, S M; Westbrook, C K; Pitz, W J; Mehl, M; Togbe, C; Dagaut, P; Wang, H; Oehlschlaeger, M; NIemann, U; Seshadri, K; Veloo, P S; Ji, C; Egolfopoulos, F; Lu, T

2011-03-16T23:59:59.000Z

2

Recent Developments in No-Core Shell-Model Calculations  

SciTech Connect

We present an overview of recent results and developments of the no-core shell model (NCSM), an ab initio approach to the nuclear many-body problem for light nuclei. In this aproach, we start from realistic two-nucleon or two- plus three-nucleon interactions. Many-body calculations are performed using a finite harmonic-oscillator (HO) basis. To facilitate convergence for realistic inter-nucleon interactions that generate strong short-range correlations, we derive effective interactions by unitary transformations that are tailored to the HO basis truncation. For soft realistic interactions this might not be necessary. If that is the case, the NCSM calculations are variational. In either case, the ab initio NCSM preserves translational invariance of the nuclear many-body problem. In this review, we, in particular, highlight results obtained with the chiral two- plus three-nucleon interactions. We discuss efforts to extend the applicability of the NCSM to heavier nuclei and larger model spaces using importance-truncation schemes and/or use of effective interactions with a core. We outline an extension of the ab initio NCSM to the description of nuclear reactions by the resonating group method technique. A future direction of the approach, the ab initio NCSM with continuum, which will provide a complete description of nuclei as open systems with coupling of bound and continuum states is given in the concluding part of the review.

Navratil, P; Quaglioni, S; Stetcu, I; Barrett, B R

2009-03-20T23:59:59.000Z

3

A Multilayer Cost Model for Metro/Core Networks  

Science Journals Connector (OSTI)

A capital expenditure model is a key requirement to evaluate multilayer (ML) metro and core network architectures. Based on the Internet protocol/multiprotocol label switching...

Rambach, Franz; Konrad, Beate; Dembeck, Lars; Gebhard, Ulrich; Gunkel, Matthias; Quagliotti, Marco; Serra, Laura; López, Víctor

2013-01-01T23:59:59.000Z

4

Bacterial Fouling in a Model Core System  

Science Journals Connector (OSTI)

...to reduce permeability. Therefore...aspects of reservoir rock, without...an "open" sandstone. Thus, especially...changes in permeability that occurred...22). The porosity of the cores...liquid storage reservoir with a capacity...

J. C. Shaw; B. Bramhill; N. C. Wardlaw; J. W. Costerton

1985-03-01T23:59:59.000Z

5

Modeling the Arm II core in MicroCap IV  

SciTech Connect

This paper reports on how an electrical model for the core of the Arm II machine was created and how to use this model. We wanted to get a model for the electrical characteristics of the ARM II core, in order to simulate this machine and to assist in the design of a future machine. We wanted this model to be able to simulate saturation, variable loss, and reset. Using the Hodgdon model and the circuit analysis program MicroCap IV, this was accomplished. This paper is written in such a way as to allow someone not familiar with the project to understand it.

Dalton, A.C.

1996-11-01T23:59:59.000Z

6

Compact stars with a quark core within the Nambu-Jona-Lasinio (NJL) model  

SciTech Connect

An ultraviolet cutoff dependent on the chemical potential as proposed by Casalbuoni et al. is used in the SU(3) Nambu-Jona-Lasinio model. The model is applied to the description of stellar quark matter and compact stars. It is shown that with a new cutoff parametrization it is possible to obtain stable hybrid stars with a quark core. A larger cutoff at finite densities leads to a partial chiral symmetry restoration of quark s at lower densities. A direct consequence is the onset of the s quark in stellar matter at lower densities and a softening of the equation of state.

Lenzi, C. H. [Departamento de Fisica, Instituto Tecnologico de Aeronautica, Campo Montenegro, Sao Jose dos Campos, SP, 12228-900 (Brazil); Centro de Fisica Computacional, Department of Physics, University of Coimbra, Rua Larga, Coimbra, P-3004-516 (Portugal); Schneider, A. S. [Department of Physics, Indiana University, Swain Hall West 117, 727 East Third Street Bloomington, Indiana 47405 (United States); Providencia, C. [Centro de Fisica Computacional, Department of Physics, University of Coimbra, Rua Larga, Coimbra, P-3004-516 (Portugal); Marinho, R. M. Jr. [Departamento de Fisica, Instituto Tecnologico de Aeronautica, Campo Montenegro, Sao Jose dos Campos, SP, 12228-900 (Brazil)

2010-07-15T23:59:59.000Z

7

Model for LMFBR core transient analysis in real time  

SciTech Connect

Plant safety as well as plant availability can be significantly improved if functions such as data validation, plant state verification, and fault identification are automated. A methodology for automation of these functions was presented in an earlier paper. To implement this methodology, plant models that run significantly faster than real transient time are needed. Such models for the intermediate heat exchanger and a once-through liquid-metal fast breeder reactor (LMFBR) steam generator have been presented. This paper discusses the modeling of LMFBR core transients. It is shown that, with a proper choice of shape functions, a nodal approximation of the coolant, cladding, and fuel temperature distributions leads to adequately accurate power and temperature predictions, as well as adequately short computation times. From the point of view of operational safety, it is desirable to terminate a transient before sodium boiling is initiated in the core. Thus, only the modeling of the preboiling phase of core transients is discussed.

Tzanos, C.P.

1986-01-01T23:59:59.000Z

8

Model for LMFBR core transient analysis in real-time  

SciTech Connect

This paper discusses the modeling of LMFBR core transients. It is shown that with a proper choice of shape functions a nodal approximation of the coolant, cladding, and fuel temperature distributions leads to adequately accurate power and temperature predictions, as well as adequately short computation times.

Tzanos, C.P.

1986-01-01T23:59:59.000Z

9

Forecast Calls for Better Models: Examining the Core  

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

Forecast Calls for Better Models: Examining the Core Forecast Calls for Better Models: Examining the Core Components of Arctic Clouds to Clear Their Influence on Climate For original submission and image(s), see ARM Research Highlights http://www.arm.gov/science/highlights/ Research Highlight Predicting how atmospheric aerosols influence cloud formation and the resulting feedback to climate is a challenge that limits the accuracy of atmospheric models. This is especially true in the Arctic, where mixed-phase (both ice- and liquid-based) clouds are frequently observed, but the processes that determine their composition are poorly understood. To obtain a closer look at what makes up Arctic clouds, scientists characterized cloud droplets and ice crystals collected at the North Slope of Alaska as part of the Indirect and Semi-Direct Aerosol Campaign (ISDAC) field study

10

Development of two mix model postprocessors for the investigation of shell mix in indirect drive implosion cores  

SciTech Connect

The presence of shell mix in inertial confinement fusion implosion cores is an important characteristic. Mixing in this experimental regime is primarily due to hydrodynamic instabilities, such as Rayleigh-Taylor and Richtmyer-Meshkov, which can affect implosion dynamics. Two independent theoretical mix models, Youngs' model and the Haan saturation model, were used to estimate the level of Rayleigh-Taylor mixing in a series of indirect drive experiments. The models were used to predict the radial width of the region containing mixed fuel and shell materials. The results for Rayleigh-Taylor mixing provided by Youngs' model are considered to be a lower bound for the mix width, while those generated by Haan's model incorporate more experimental characteristics and consequently have larger mix widths. These results are compared with an independent experimental analysis, which infers a larger mix width based on all instabilities and effects captured in the experimental data.

Welser-Sherrill, L.; Mancini, R. C. [Department of Physics, University of Nevada, Reno, Nevada 89557 (United States); Haynes, D. A. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Haan, S. W.; Koch, J. A.; Izumi, N.; Tommasini, R. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Golovkin, I. E.; MacFarlane, J. J. [Prism Computational Sciences, Madison, Wisconsin 53703 (United States); Radha, P. B.; Delettrez, J. A.; Regan, S. P.; Smalyuk, V. A. [Laboratory for Laser Energetics, Rochester, New York 14623 (United States)

2007-07-15T23:59:59.000Z

11

Bayesian modelling of the cool core galaxy group NGC 4325  

E-Print Network (OSTI)

We present an X-ray analysis of the radio-quiet cool-core galaxy group NGC 4325 (z=0.026) based on Chandra and ROSAT observations. The Chandra data were analysed using XSPEC deprojection, 2D spectral mapping and forward-fitting with parametric models. Additionally, a Markov chain Monte Carlo method was used to perform a joint Bayesian analysis of the Chandra and ROSAT data. The results of the various analysis methods are compared, particularly those obtained by forward-fitting and deprojection. The spectral mapping reveals the presence of cool gas displaced up to 10 kpc from the group centre. The Chandra X-ray surface brightness shows the group core to be highly disturbed, and indicates the presence of two small X-ray cavities within 15 kpc of the group core. The XSPEC deprojection analysis shows that the group has a particularly steep entropy profile, suggesting that an AGN outburst may be about to occur. With the evidence of prior AGN activity, but with no radio emission currently observed, we suggest that the group in in a pre-outburst state, with the cavities and displaced gas providing evidence of a previous, weak AGN outburst.

Paul A. Russell; Trevor J. Ponman; Alastair J. R. Sanderson

2007-03-01T23:59:59.000Z

12

Benchmarking spin-state chemistry in starless core models  

E-Print Network (OSTI)

Aims. We aim to present simulated chemical abundance profiles for a variety of important species, with special attention given to spin-state chemistry, in order to provide reference results against which present and future models can be compared. Methods. We employ gas-phase and gas-grain models to investigate chemical abundances in physical conditions corresponding to starless cores. To this end, we have developed new chemical reaction sets for both gas-phase and grain-surface chemistry, including the deuterated forms of species with up to six atoms and the spin-state chemistry of light ions and of the species involved in the ammonia and water formation networks. The physical model is kept simple in order to facilitate straightforward benchmarking of other models against the results of this paper. Results. We find that the ortho/para ratios of ammonia and water are similar in both gas-phase and gas-grain models, at late times in particular, implying that the ratios are determined by gas-phase processes. We d...

Sipilä, O; Harju, J

2015-01-01T23:59:59.000Z

13

Hard-core lattice model of multiphase systems  

Science Journals Connector (OSTI)

The cooperative-problem lattice model for gases, liquids, and solids on a face-centered-cubic lattice is approximately solved. A hard-core interaction is assumed between particles on nearest-, next-nearest-, and on next-but-one nearest-neighbor lattice sites. Particles on lattice sites which are at a greater distance from one another are connected by an arbitrary soft pair interaction whose zero Fourier component may be positive or negative. By considering not only homogeneous particle distributions but also some simple periodical particle distributions on the lattice we can, in the case of a mean attractive soft particle interaction, prove the possibility of the existence of four thermodynamical stable phases: a gas phase, a liquid phase, a solid modification with a face-centered-cubic periodical structure, and a solid modification with a simple cubic periodical structure. Transitions between these phases can take place.

H. P. Neumann

1975-10-01T23:59:59.000Z

14

Validation of a model for faster than real time LMFBR core transient analysis  

SciTech Connect

This report briefly describes experimental validation of a computer model used to analyze LMFBR type core transients. This model is used to predict coolant, cladding, and fuel temperature distributions during transient overpower accidents. (JDH)

Tzanos, C.P.

1987-01-01T23:59:59.000Z

15

Cross-Validation of SWERA's Core Radiative Transfer Models - Partial Report  

Open Energy Info (EERE)

Cross-Validation of SWERA's Core Radiative Transfer Models - Partial Report Cross-Validation of SWERA's Core Radiative Transfer Models - Partial Report Dataset Summary Description (Abstract): This partial report describes the results obtained by two of the core radiative transfer models adopted in the SWERA Project for global horizontal solar irradiation during the cross-validation step. They are BRASIL-SR and SUNY-ALBANY models (Martins, 2001; Stuhlmann et al. 1990; Perez et al., 2002). The results from other two other core models, NREL and DLR, are not yet available. The HELIOSAT was included as a reference model at this stage. The HELIOSAT model is widely employed for solar energy assessment in Europe and is well know by the solar energy community worldwide (Beyer et al., 1996; Cano et al., 1986). (Purpose): SWERA solar cross-validation study

16

Modeling percolation in high-aspect-ratio fiber systems. I. Soft-core versus hard-core models L. Berhan1,  

E-Print Network (OSTI)

. Indeed, experimental findings in nanotube- reinforced polymeric 1­11 and ceramic 12 matrix mate- rials in nanotubes-reinforced composites. The hard-core model can also potentially be used as a tool in calculating the tunneling distance in composite materials, given the fiber morphology and experimentally derived electrical

Sastry, Ann Marie

17

The Physics of Low Energy Solar "Today neutrinos have a larger and larger place in  

E-Print Network (OSTI)

Chapter 1 The Physics of Low Energy Solar Neutrinos "Today neutrinos have a larger and larger place oscillations could na¨ively be 1 #12;Chapter 1: The Physics of Low Energy Solar Neutrinos 2 accommodated simply of Low Energy Solar Neutrinos 3 first directly detected more than two decades later in 1953. Reines

18

Validated Model-Based Performance Prediction of Multi-Core Software Routers  

E-Print Network (OSTI)

Terms--measurement, simulation, intra-node model, re- source contention, model validation, software components. Leveraged by high flexibility and low costs of software developments in comparison with hardwareValidated Model-Based Performance Prediction of Multi-Core Software Routers Torsten Meyer1

Carle, Georg

19

Why Do Continuum Gas-Solids Flow Models Predict Core-Annulus Flow?  

SciTech Connect

Core-annulus flow is an experimentally well established, industrially significant flow pattern of circulating fluidized beds. Several studies reported in the literature have shown that continuum gas-solids flow models are able to predict that flow pattern. But the crucial features of the model that give rise to the core-annulus flow structure have not been identified. To determine those features, we conduct transient simulations and analyze the results. Furthermore we time-average the results and investigate the formulation of time-averaged equations. We use transient, highly resolved, 1-D, grid-independent numerical solutions of a continuum model in this study. We show that the results could be even qualitatively incorrect (high solids concentration at the center of the channel) unless grid-independence is established. This explains why in certain coarse grid computations reported in the literature it was necessary to remove a dissipation term or to increase the particle size. Our simulations verify that the core-annulus structure arises in a time-averaged sense from unsteady gas-solids flow, as observed in experiments. We show that the key term that makes the flow unsteady is the dissipation term in the granular energy equation. Without that term the simulation yields a steady-state solution. The intuition based on steady-state solutions may not be valid. Unlike steady-state solutions, the transient solutions are not unduly sensitive to the restitution coefficient. The effect of restitution coefficient in transient simulations is remarkably different: a smaller restitution coefficient gives a higher average granular temperature. Both the micro-scale (clusters resolved) and meso-scale (clusters time-averaged) phenomena are important, unlike turbulent single-phase flows where the meso-scale (turbulent) stresses dominate. The prediction of core-annulus flow is strongly affected by the parameters used in the (micro-scale) wall boundary conditions; it is essential that the parameters are such that no granular energy is produced at the wall. The normal stress based on kinetic theory (Ps, micro) is an order of magnitude larger than normal stress arising from fluctuations (Ps, meso). Therefore, the granular temperature and solids fraction are approximately inversely correlated, just as shown by a steady-state analysis. However, the gradient of Ps, micro is of the same order of magnitude as the gradient of Ps, meso; those gradients adjust to ensure that the time averaged total Ps gradient in the radial direction is zero. The meso-scale shear stress is larger than the micro-scale shear stress. The meso-scale granular energy production term dominates the corresponding micro-scale term and must be included in time-averaged equations. That term is responsible for the maximum at the center in the granular temperature profile. The micro-scale granular energy production term is identically zero at the center because it is proportional to the gradient of solids velocity, which is zero at the center. The instantaneous gradient of solids velocity at the center, however, is not zero because of the down flow of clusters near the walls; it takes positive and negative values making the time-averaged velocity gradient exactly zero at the center. Therefore, the time-averaged square of the velocity gradient is non-zero at the center, which results in a production term in the time-averaged equations that is non-zero at the center. We find that the predictions are insensitive to the currently available k-å type turbulence models. The traditional k-å type models, based on the experience with single phase flow calculations, may not be adequate because meso-scale terms do not necessarily dominate the micro-scale terms. And certain parameters could behave counter to our intuition based on single phase flows: we compute and confirm with physical arguments that the gas-phase turbulent (meso-scale) viscosity could become negative.

Benyahia, S.; Syamlal, M.; O'Brien, T.J.

2006-11-01T23:59:59.000Z

20

A model for the transient behavior of an iron-core transformer  

E-Print Network (OSTI)

A MODEL FOR THE TRANSIENT BEHAVIOR OF AN IRON-CORE TRANSFORMER A Thesis by JAMES EDWARD PLATTS Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May... 1968 Major Subject: ELECTRICAL ENGINEERING A MODEL FOR THE TRANSIENT BEHAVIOR OF AN IRON-CORE TRANSFORMER A Thesis by JAMES EDWARD PLATTS Approved as to style and content by: airman of ommittee Hea o epartm t Member em er ( Member May 1968...

Platts, James Edward

1968-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

A Larger Slice or a Larger Pie? An Empirical Investigation of Bargaining Power in the Distribution Channel  

E-Print Network (OSTI)

A Larger Slice or a Larger Pie? An Empirical InvestigationA Larger Slice or a Larger Pie? An Empirical Investigationbe cases where the slice of the pie that goes to one of the

Draganska, Michaela; Klapper, Daniel; Villas-Boas, Sofia B

2008-01-01T23:59:59.000Z

22

CPT: An Energy-Efficiency Model for Multi-core Computer Systems  

E-Print Network (OSTI)

CPT: An Energy-Efficiency Model for Multi-core Computer Systems Weisong Shi, Shinan Wang and Bing efficiency of computer systems. These techniques affect the energy efficiency across different layers metric that represents the energy efficiency of a computer system, for a specific configuration, given

Shi, Weisong

23

CB17: Inferring the dynamical history of a prestellar core with chemo-dynamical models  

E-Print Network (OSTI)

We present a detailed theoretical study of the isolated Bok globule CB17 (L1389) based on spectral maps of CS, HCO$^+$, C$^{18}$O, C$^{34}$S, and H$^{13}$CO$^+$ lines. A phenomenological model of prestellar core evolution, a time-dependent chemical model, and a radiative transfer simulation for molecular lines are combined to reconstruct the chemical and kinematical structure of this core. We developed a general criterion that allows to quantify the difference between observed and simulated spectral maps. By minimizing this difference, we find that very high and very low values of the effective sticking probability $S$ are not appropriate for the studied prestellar core. The most probable $S$ value for CB17 is 0.3--0.5. The spatial distribution of the intensities and self-absorption features of optically thick lines is indicative of UV irradiation of the core. By fitting simultaneously optically thin and optically thick transitions, we isolate the model that reproduces all the available spectral maps to a reasonable accuracy. The line asymmetry pattern in CB17 is reproduced by a combination of infall, rotation, and turbulent motions with velocities $\\sim0.05$ km s$^{-1}$, $\\sim0.1$ km s$^{-1}$, and $\\sim0.1$ km s$^{-1}$, respectively. These parameters corresponds to energy ratios $E_{\\rm rot}/E_{\\rm grav}\\approx0.03$, $E_{\\rm therm}/E_{\\rm grav}\\approx0.8$, and $E_{\\rm turb}/E_{\\rm grav}\\approx0.05$ (the rotation parameters are determined for $i=90^\\circ$). The chemical age of the core is about 2 Myrs. In particular, this is indicated by the central depletion of CO, CS, and HCO$^+$. Based on the angular momentum value, we argue that the core is going to fragment, i.e., to form a binary (multiple) star. (abridged)

Ya. Pavlyuchenkov; D. Wiebe; R. Launhardt; Th. Henning

2006-03-22T23:59:59.000Z

24

Core Analysis For The Development And Constraint Of Physical Models Of  

Open Energy Info (EERE)

For The Development And Constraint Of Physical Models Of For The Development And Constraint Of Physical Models Of Geothermal Reservoirs Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Core Analysis For The Development And Constraint Of Physical Models Of Geothermal Reservoirs Details Activities (2) Areas (2) Regions (0) Abstract: Effective reservoir exploration, characterization, and engineering require a fundamental understanding of the geophysical properties of reservoir rocks and fracture systems. Even in the best of circumstances, spatial variability in porosity, fracture density, salinity, saturation, tectonic stress, fluid pressures, and lithology can all potentially produce and/or contribute to geophysical anomalies. As a result, serious uniqueness problems frequently occur when interpreting

25

Beyond the pseudo-time-dependent approach: chemical models of dense core precursors  

E-Print Network (OSTI)

Context: Chemical models of dense cloud cores often utilize the so-called pseudo-time-dependent approximation, in which the physical conditions are held fixed and uniform as the chemistry occurs. In this approximation, the initial abundances chosen, which are totally atomic in nature except for molecular hydrogen, are artificial. A more detailed approach to the chemistry of dense cold cores should include the physical evolution during their early stages of formation. Aims: Our major goal is to investigate the initial synthesis of molecular ices and gas-phase molecules as cold molecular gas begins to form behind a shock in the diffuse interstellar medium. The abundances calculated as the conditions evolve can then be utilized as reasonable initial conditions for a theory of the chemistry of dense cores. Methods: Hydrodynamic shock-wave simulations of the early stages of cold core formation are used to determine the time-dependent physical conditions for a gas-grain chemical network. We follow the cold post-sho...

Hassel, G E; Bergin, E A

2010-01-01T23:59:59.000Z

26

Failure Predictions for VHTR Core Components using a Probabilistic Contiuum Damage Mechanics Model  

SciTech Connect

The proposed work addresses the key research need for the development of constitutive models and overall failure models for graphite and high temperature structural materials, with the long-term goal being to maximize the design life of the Next Generation Nuclear Plant (NGNP). To this end, the capability of a Continuum Damage Mechanics (CDM) model, which has been used successfully for modeling fracture of virgin graphite, will be extended as a predictive and design tool for the core components of the very high- temperature reactor (VHTR). Specifically, irradiation and environmental effects pertinent to the VHTR will be incorporated into the model to allow fracture of graphite and ceramic components under in-reactor conditions to be modeled explicitly using the finite element method. The model uses a combined stress-based and fracture mechanics-based failure criterion, so it can simulate both the initiation and propagation of cracks. Modern imaging techniques, such as x-ray computed tomography and digital image correlation, will be used during material testing to help define the baseline material damage parameters. Monte Carlo analysis will be performed to address inherent variations in material properties, the aim being to reduce the arbitrariness and uncertainties associated with the current statistical approach. The results can potentially contribute to the current development of American Society of Mechanical Engineers (ASME) codes for the design and construction of VHTR core components.

Fok, Alex

2013-10-30T23:59:59.000Z

27

A spectral transform dynamical core option within the Community Atmosphere Model (CAM4)  

SciTech Connect

A spectral transform dynamical core with an 85 spectral truncation resolution (T85) within the Community Atmosphere Model (CAM), version 4, is evaluated within the recently released Community Earth System Model, version 1.0 (CESM) global climate model. The spectral dynamical core option provides a well-known base within the climate model community from which to assess climate behavior and statistics, and its relative computational efficiency for smaller computing platforms allows it to be extended to perform climate length simulations using high-resolution configurations in the near term. To establish the characteristics of the CAM4 T85, an ensemble of simulations covering the present day observational period using forced sea surface temperatures and prescribed sea-ice extent are evaluated. Overall, the T85 ensemble attributes and biases are similar to a companion ensemble of simulations using the one degree finite volume (FV1) dynamical core, relative to observed and model derived datasets. Notable improvements with T85 compared to FV1 include the representation of wintertime Arctic sea level pressure and summer precipitation over the Western Indian subcontinent. The mean and spatial patterns of the land surface temperature trends over the AMIP period are generally well simulated with the T85 ensemble relative to observations, however the model is not able to capture the extent nor magnitude of changes in temperature extremes over the boreal summer, where the changes are most dramatic. Biases in the wintertime Arctic surface temperature and annual mean surface stress fields persist with T85 as with the CAM3 version of T85.

Evans, Katherine J [ORNL; Mahajan, Salil [ORNL; Branstetter, Marcia L [ORNL; McClean, Julie L. [Scripps Institute of Oceanography; Caron, Julie M. [National Center for Atmospheric Research (NCAR); Maltrud, Matthew E. [Los Alamos National Laboratory (LANL); Hack, James J [ORNL; Bader, David C [ORNL; Neale, Rich [National Center for Atmospheric Research (NCAR)

2014-01-01T23:59:59.000Z

28

Severe accident modeling of a PWR core with different cladding materials  

SciTech Connect

The MAAP v.4 software has been used to model two severe accident scenarios in nuclear power reactors with three different materials as fuel cladding. The TMI-2 severe accident was modeled with Zircaloy-2 and SiC as clad material and a SBO accident in a Zion-like, 4-loop, Westinghouse PWR was modeled with Zircaloy-2, SiC, and 304 stainless steel as clad material. TMI-2 modeling results indicate that lower peak core temperatures, less H 2 (g) produced, and a smaller mass of molten material would result if SiC was substituted for Zircaloy-2 as cladding. SBO modeling results indicate that the calculated time to RCS rupture would increase by approximately 20 minutes if SiC was substituted for Zircaloy-2. Additionally, when an extended SBO accident (RCS creep rupture failure disabled) was modeled, significantly lower peak core temperatures, less H 2 (g) produced, and a smaller mass of molten material would be generated by substituting SiC for Zircaloy-2 or stainless steel cladding. Because the rate of SiC oxidation reaction with elevated temperature H{sub 2}O (g) was set to 0 for this work, these results should be considered preliminary. However, the benefits of SiC as a more accident tolerant clad material have been shown and additional investigation of SiC as an LWR core material are warranted, specifically investigations of the oxidation kinetics of SiC in H{sub 2}O (g) over the range of temperatures and pressures relevant to severe accidents in LWR 's. (authors)

Johnson, S. C. [Westinghouse Electric Company LLC, 5801 Bluff Road, Columbia, SC 29209 (United States); Henry, R. E.; Paik, C. Y. [Fauske and Associates, Inc., 16W070 83rd Street, Burr Ridge, IL 60527 (United States)

2012-07-01T23:59:59.000Z

29

Fuel performance models for high-temperature gas-cooled reactor core design  

SciTech Connect

Mechanistic fuel performance models are used in high-temperature gas-cooled reactor core design and licensing to predict failure and fission product release. Fuel particles manufactured with defective or missing SiC, IPyC, or fuel dispersion in the buffer fail at a level of less than 5 x 10/sup -4/ fraction. These failed particles primarily release metallic fission products because the OPyC remains intact on 90% of the particles and retains gaseous isotopes. The predicted failure of particles using performance models appears to be conservative relative to operating reactor experience.

Stansfield, O.M.; Simon, W.A.; Baxter, A.M.

1983-09-01T23:59:59.000Z

30

NUMERICAL VERIFICATION OF THE RELAP-7 CORE CHANNEL SINGLE-PHASE MODEL  

SciTech Connect

The RELAP-7 code is the next generation of nuclear reactor system safety analysis code being developed at the Idaho National Laboratory (INL). All the physics in RELAP-7 are fully coupled and the errors resulted from the traditional operator-splitting approach are eliminated. By using 2nd order methods in both time and space and eliminating operator-splitting errors, the numerical error of RELAP-7 can be minimized. Numerical verification is the process to verify the orders of numerical methods. It is an important part of modern verification and validation process. The core channel component in RELAP-7 is designed to simulate coolant flow as well as the conjugated heat transfer between coolant flow and the fuel rod. A special treatment at fuel centerline to avoid numerical singularity for the cylindrical heat conduction in the continuous finite element mesh is discussed. One steady state test case and one fast power up transient test case are utilized for the verification of the core channel model with single-phase flow. Analytical solution for the fuel pin temperature and figures of merit such as peak clad temperature and peak fuel temperature are used to define numerical errors. These cases prove that the mass and energy are well conserved and 2nd order convergence rates for both time and space are achieved in the core channel model.

Haihua Zhao; Ling Zou; Hongbin Zhang; Richard Martineau

2014-06-01T23:59:59.000Z

31

Larger Turbines and the Future Cost of Wind Energy (Poster)  

SciTech Connect

The move to larger turbines has been observed in the United States and around the world. Turbine scaling increases energy capture while reducing general project infrastructure costs and landscape impacts, each of which of can reduce the cost of wind energy. However, scaling in the absence of innovation, can increase turbine costs. The ability of turbine designers and manufacturers to continue to scale turbines, while simultaneously reducing costs, is an important factor in long-term viability of the industry. This research seeks to better understand how technology innovation can allow the continued development of larger turbines on taller towers while also achieving lower cost of energy. Modeling incremental technology improvements identified over the past decade demonstrates that cost reductions on the order of 10%, and capacity factor improvements on the order of 5% (for sites with annual mean wind speed of 7.25 m/s at 50m), are achievable for turbines up to 3.5 MW. However, to achieve a 10% cost reduction and a 10% capacity factor improvement for turbines up to 5 MW, additional technology innovations must be developed and implemented.

Lantz, E.; Hand, M.

2011-03-01T23:59:59.000Z

32

TRACE/PARCS Core Modeling of a BWR/5 for Accident Analysis of ATWS Events  

SciTech Connect

The TRACE/PARCS computational package [1, 2] isdesigned to be applicable to the analysis of light water reactor operational transients and accidents where the coupling between the neutron kinetics (PARCS) and the thermal-hydraulics and thermal-mechanics (TRACE) is important. TRACE/PARCS has been assessed for itsapplicability to anticipated transients without scram(ATWS) [3]. The challenge, addressed in this study, is to develop a sufficiently rigorous input model that would be acceptable for use in ATWS analysis. Two types of ATWS events were of interest, a turbine trip and a closure of main steam isolation valves (MSIVs). In the first type, initiated by turbine trip, the concern is that the core will become unstable and large power oscillations will occur. In the second type,initiated by MSIV closure,, the concern is the amount of energy being placed into containment and the resulting emergency depressurization. Two separate TRACE/PARCS models of a BWR/5 were developed to analyze these ATWS events at MELLLA+ (maximum extended load line limit plus)operating conditions. One model [4] was used for analysis of ATWS events leading to instability (ATWS-I);the other [5] for ATWS events leading to emergency depressurization (ATWS-ED). Both models included a large portion of the nuclear steam supply system and controls, and a detailed core model, presented henceforth.

Cuadra A.; Baek J.; Cheng, L.; Aronson, A.; Diamond, D.; Yarsky, P.

2013-11-10T23:59:59.000Z

33

Improved Models of Stellar Core Collapse and Still no Explosions: What is Missing?  

E-Print Network (OSTI)

Two-dimensional hydrodynamic simulations of stellar core-collapse with and without rotation are presented which for the first time were performed by solving the Boltzmann equation for the neutrino transport including a state-of-the-art description of neutrino interactions. Although convection develops below the neutrinosphere and in the neutrino-heated region behind the supernova shock, the models do not explode. This suggests missing physics, possibly with respect to the nuclear equation of state and weak interactions in the subnuclear regime. However, it might also indicate a fundamental problem of the neutrino-driven explosion mechanism.

R. Buras; M. Rampp; H. -Th. Janka; K. Kifonidis

2003-03-07T23:59:59.000Z

34

Modeling Stress Strain Relationships and Predicting Failure Probabilities For Graphite Core Components  

SciTech Connect

This project will implement inelastic constitutive models that will yield the requisite stress-strain information necessary for graphite component design. Accurate knowledge of stress states (both elastic and inelastic) is required to assess how close a nuclear core component is to failure. Strain states are needed to assess deformations in order to ascertain serviceability issues relating to failure, e.g., whether too much shrinkage has taken place for the core to function properly. Failure probabilities, as opposed to safety factors, are required in order to capture the bariability in failure strength in tensile regimes. The current stress state is used to predict the probability of failure. Stochastic failure models will be developed that can accommodate possible material anisotropy. This work will also model material damage (i.e., degradation of mechanical properties) due to radiation exposure. The team will design tools for components fabricated from nuclear graphite. These tools must readily interact with finite element software--in particular, COMSOL, the software algorithm currently being utilized by the Idaho National Laboratory. For the eleastic response of graphite, the team will adopt anisotropic stress-strain relationships available in COMSO. Data from the literature will be utilized to characterize the appropriate elastic material constants.

Duffy, Stephen

2013-09-09T23:59:59.000Z

35

Scientists detect methane levels three times larger than expected...  

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

methane that actually preceded recent concerns about potential emissions from fracking," Dubey said. Scientists detect methane levels three times larger than expected over...

36

Calculational-experimental research models for a fast reactor with a heterogeneous core  

SciTech Connect

The physical characteristics of heterogeneous metallic oxide cores were experimentally studied by physical tests of the critical assemblies BFS-46 and BFS-46AZ, which simulate a reactor of the BN-1600 type, into the core of which a fuel assembly with metallic uranium is inserted. A calculational model for the critical assemblies being investigated, showing the zones and their dimensions, is presented. The critical assembly BFS-46AZ is a modification of the basic critical assembly BFS-46 which adds plutonium to the IBZ to simulate its accumulation during reactor operation. The BFS-46 and BFS-46AZ assemblies have identical dimensions for the IBZ and LEZ, and have different HEZ dimensions, necessary to ensure the criticality of each assembly. Plutonium with a /sup 240/Pu content equal to 3.8% is used in the LEZ. The critically parameters are calculated using one-dimensional and two-dimensional models in a 26-group diffusion approximation based on the BNAP-78 system of group constants.

Belov, S.P.; Bobrov, S.B.; Kazanskii, Yu.A.; Kuzin, E.N.; Matveev, V.I.; Novozhilov, A.I.; Chernyi, V.A.

1987-11-01T23:59:59.000Z

37

The cluster-core model for halo-structure of light nuclei at the drip lines  

E-Print Network (OSTI)

Nuclei at both the neutron- and proton-drip lines are studied. In the cluster-core model, the halo-structure of all the observed and proposed cases of neutron- or proton-halos is investigated in terms of simple potential energy surfaces calculated as the sum of binding energies, Coulomb repulsion, nuclear proximity attraction and the centrifugal potential for all the possible cluster+core configurations of a nucleus. The clusters of neutrons and protons are taken to be unbound, with additional Coulomb energy added for proton-clusters. The model predictions agree with the available experimental studies but show some differences with the nucleon separation energy hypothesis, particularly for proton-halo nuclei. Of particular interest are the halo-structures of $^{11}N$ and $^{20}Mg$. The calculated potential energy surfaces are also useful to identify the new magic numbers and molecular structures in exotic nuclei. In particular, N=6 is a possible new magic number for very neutron-deficient nuclei, but Z=N=2 and Z=8 seem to remain magic even for such nuclei, near the drip line.

Raj K. Gupta; Sushil Kumar; M. Balasubramaniam; G. Munzenberg; Werner Scheid

2011-11-08T23:59:59.000Z

38

Improved Bounds on the Phase Transition for the Hard-Core Model in 2-Dimensions  

E-Print Network (OSTI)

For the hard-core lattice gas model defined on independent sets weighted by an activity $\\lambda$, we study the critical activity $\\lambda_c(\\mathbb{Z}^2)$ for the uniqueness/non-uniqueness threshold on the 2-dimensional integer lattice $\\mathbb{Z}^2$. The conjectured value of the critical activity is approximately $3.796$. Until recently, the best lower bound followed from algorithmic results of Weitz (2006). Weitz presented an FPTAS for approximating the partition function for graphs of constant maximum degree $\\Delta$ when $\\lambda2.388$. In this paper, we establish an upper bound for this approach, by showing that, for all $\\sigma$, SSM does not hold on $T_{\\mathrm{saw}}^\\sigma(\\mathbb{Z}^2)$ when $\\lambda>3.4$. We also present a refinement of the approach of Restrepo et al. which improves the lower bound to $\\lambda_c(\\mathbb{Z}^2)>2.48$.

Juan C. Vera; Eric Vigoda; Linji Yang

2014-07-09T23:59:59.000Z

39

Collaboration between varied organizations develops larger, more precise  

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

The Large Area Picosecond Photodetector (LAPPD) collaboration has developed cheaper, larger, more robust microchannel plates, seen here at a test facility at Argonne. The LAPPD team has partnered with Massachusetts-based fiber optics company INCOM Inc. to manufacture the plates. Click to enlarge. The Large Area Picosecond Photodetector (LAPPD) collaboration has developed cheaper, larger, more robust microchannel plates, seen here at a test facility at Argonne. The LAPPD team has partnered with Massachusetts-based fiber optics company INCOM Inc. to manufacture the plates. Click to enlarge. The Large Area Picosecond Photodetector (LAPPD) collaboration has developed cheaper, larger, more robust microchannel plates, seen here at a test facility at Argonne. The LAPPD team has partnered with Massachusetts-based fiber optics company INCOM Inc. to manufacture the plates. Click to enlarge. Collaboration between varied organizations develops larger, more precise photodetectors for the market By Chelsea Leu * November 5, 2013 Tweet EmailPrint Scientific particle detectors, medical imaging devices and cargo scanners

40

Core-crust transition properties of neutron stars within systematically varied extended relativistic mean-field model  

E-Print Network (OSTI)

The model dependence and the symmetry energy dependence of the core-crust transition properties for the neutron stars are studied using three different families of systematically varied extended relativistic mean field model. Several forces within each of the families are so considered that they yield wide variations in the values of the nuclear symmetry energy $a_{\\rm sym}$ and its slope parameter $L$ at the saturation density. The core-crust transition density is calculated using a method based on random-phase-approximation. The core-crust transition density is strongly correlated, in a model independent manner, with the symmetry energy slope parameter evaluated at the saturation density. The pressure at the transition point dose not show any meaningful correlations with the symmetry energy parameters at the saturation density. At best, pressure at the transition point is correlated with the symmetry energy parameters and their linear combination evaluated at the some sub-saturation density. Yet, such corre...

Sulaksono, A; Agrawal, B K

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


41

Thermodynamics and Structural Properties of the High Density Gaussian Core Model  

E-Print Network (OSTI)

We numerically study thermodynamic and structural properties of the one-component Gaussian core model (GCM) at very high densities. The solid-fluid phase boundary is carefully determined. We find that the density dependence of both the freezing and melting temperatures obey the asymptotic relation, $\\log T_f$, $\\log T_m \\propto -\\rho^{2/3}$, where $\\rho$ is the number density, which is consistent with Stillinger's conjecture. Thermodynamic quantities such as the energy and pressure and the structural functions such as the static structure factor are also investigated in the fluid phase for a wide range of temperature above the phase boundary. We compare the numerical results with the prediction of the liquid theory with the random phase approximation (RPA). At high temperatures, the results are in almost perfect agreement with RPA for a wide range of density, as it has been already shown in the previous studies. In the low temperature regime close to the phase boundary line, although RPA fails to describe the structure factors and the radial distribution functions at the length scales of the interparticle distance, it successfully predicts their behaviors at shorter length scales. RPA also predicts thermodynamic quantities such as the energy, pressure, and the temperature at which the thermal expansion coefficient becomes negative, almost perfectly. Striking ability of RPA to predict thermodynamic quantities even at high densities and low temperatures is understood in terms of the decoupling of the length scales which dictate thermodynamic quantities from the interparticle distance which dominates the peak structures of the static structure factor due to the softness of the Gaussian core potential.

Atsushi Ikeda; Kunimasa Miyazaki

2011-04-18T23:59:59.000Z

42

into deeper and larger-volume saline formations. Researchers at  

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

into deeper and larger-volume saline formations. Researchers at into deeper and larger-volume saline formations. Researchers at Cranfield have been monitoring the injected CO 2 with instrumentation installed nearly two miles beneath the surface to ensure the safe and permanent storage in the Lower Tuscaloosa Formations. The Cranfield project also has been successful in the deployment of pressure-response monitoring techniques in the injection zone ("in-zone") and above the injection zone ("above zone"). Real-time data collected since July 2008

43

Developing Fully Coupled Dynamical Reactor Core Isolation System Models in RELAP-7 for Extended Station Black-Out Analysis  

SciTech Connect

The reactor core isolation cooling (RCIC) system in a boiling water reactor (BWR) provides makeup water to the reactor vessel for core cooling when the main steam lines are isolated and the normal supply of water to the reactor vessel is lost. It was one of the very few safety systems still available during the Fukushima Daiichi accidents after the tsunamis hit the plants and the system successfully delayed the core meltdown for a few days for unit 2 & 3. Therefore, detailed models for RCIC system components are indispensable to understand extended station black-out accidents (SBO) for BWRs. As part of the effort to develop the new generation reactor system safety analysis code RELAP-7, major components to simulate the RCIC system have been developed. This paper describes the models for those components such as turbine, pump, and wet well. Selected individual component test simulations and a simplified SBO simulation up to but before core damage is presented. The successful implementation of the simplified RCIC and wet well models paves the way to further improve the models for safety analysis by including more detailed physical processes in the near future.

Haihua Zhao; Ling Zou; Hongbin Zhang; David Andrs; Richard Martineau

2014-04-01T23:59:59.000Z

44

A turbulent MHD model for molecular clouds and a new method of accretion on to star-forming cores  

E-Print Network (OSTI)

A turbulent MHD model for molecular clouds and a new method of accretion on to star-forming cores D gravitationally unstable and collapse to form stars. Key words: accretion, accretion discs ­ MHD ­ stars on to a well- defined pre-main-sequence track on the HR diagram (Stahler, Shu & Taam 1980), and hence

Ward-Thompson, Derek

45

Structure of the particle-hole amplitudes in no-core shell model wave functions  

SciTech Connect

We study the structure of the no-core shell model wave functions for {sup 6}Li and {sup 12}C by investigating the ground state and first excited state electron scattering charge form factors. In both nuclei, large particle-hole (ph) amplitudes in the wave functions appear with the opposite sign to that needed to reproduce the shape of the (e,e{sup '}) form factors, the charge radii, and the B(E2) values for the lowest two states. The difference in sign appears to arise mainly from the monopole DELTA(Planck constant/2pi)omega=2 matrix elements of the kinetic and potential energy (T+V) that transform under the harmonic oscillator SU(3) symmetries as (lambda,mu)=(2,0). These are difficult to determine self-consistently, but they have a strong effect on the structure of the low-lying states and on the giant monopole and quadrupole resonances. The Lee-Suzuki transformation, used to account for the restricted nature of the space in terms of an effective interaction, introduces large higher-order DELTA(Planck constant/2pi)omega=n,n>2, ph amplitudes in the wave functions. The latter ph excitations aggravate the disagreement between the experimental and predicted (e,e{sup '}) form factors with increasing model spaces, especially at high momentum transfers. For sufficiently large model spaces, the situation begins to resolve itself for {sup 6}Li, but the convergence is slow. A prescription to constrain the ph excitations would likely accelerate convergence of the calculations.

Hayes, A. C. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Kwiatkowski, A. A. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

2010-05-15T23:59:59.000Z

46

Collision cascades and sputtering induced by larger cluster ions  

SciTech Connect

Recent experimental work on larger cluster impact on solid surfaces suggests large deviations from the standard case of additive sputter yields both in the nuclear and electronic stopping regime. The paper concentrates on elastic collision cascades. In addition to very pronounced spike effects, two phenomena are pointed out that are specific to cluster bombardment. Multiple hits of cluster atoms on one and the same target atom may result in recoil atoms that move faster than the maximum recoil speed for monomer bombardment at the same projectile speed. This effect is important when the atomic mass of a beam atom is less than that of a target atom, M1 << M2. In the opposite case, M1 >> M2, collisions between beam particles may accelerate some beam particles and slow down others. Some consequences are mentioned. Remarks on the nuclear stopping power of larger clusters and on electronic sputtering by cluster bombardment conclude the paper. 38 refs., 2 figs.

Sigmund, P.

1988-01-01T23:59:59.000Z

47

8.4 White Dwarfs As an asymptotic giant branch star becomes larger and more luminous, the  

E-Print Network (OSTI)

8.4 White Dwarfs As an asymptotic giant branch star becomes larger and more luminous, the rate is the reminant core, the white dwarf. Our knowledge of white dwarfs began in 1850 with the discovery be both hot and faint was for Sirius B to be very, very small, and so they were called white dwarf stars

Peletier, Reynier

48

Neutron Scattering Studies and Modeling of the HMG 14 Core Nucleosome Complex  

Science Journals Connector (OSTI)

There is considerable evidence relating the nonhistone proteins HMG 14 and HMG 17 with the structure of active or protentially active chromatin. In this study, bulk nucleosome core particles prepared from chicken...

E. C. Uberbacher; D. E. Olins; G. J. Bunick; W. C. Koehler

1984-01-01T23:59:59.000Z

49

Effects of turbulence model on convective heat transfer of coolant flow in a prismatic very high temperature reactor core  

SciTech Connect

The existing study of Spall et al. shows that only {nu}{sup 2}-f turbulence model well matches with the experimental data of Shehata and McEligot which were obtained under strongly heated gas flows. Significant over-predictions in those literatures were observed in the convective heat transfer with the other famous turbulence models such as the k-{epsilon} and k-{omega} models. In spite of such good evidence about the performance of the{nu}{sup 2}-f model, the application of the {nu}{sup 2}-f model to the thermo-fluid analysis of a prismatic core is very rare. In this paper, therefore, the convective heat transfer of the coolant flow in a prismatic core has been investigated using the {nu}{sup 2}-f model. Computational fluid dynamics (CFD) calculations have been carried out for the typical unit cell geometry of a prismatic fuel column with typical operating conditions of prismatic designs. The tested Reynolds numbers of the coolant flow are 10,000, 20,000, 30,000 and 50,000. The predicted Nusselt numbers with the {nu}{sup 2}-f model are compared with the results by the other turbulence models (k-{epsilon} and SST) as well as the empirical correlations. (authors)

Lee, S. N.; Tak, N. I.; Kim, M. H.; Noh, J. M. [Korea Atomic Energy Research Inst., Daedeok-daero 989-11, Yuseong-gu, Daejeon (Korea, Republic of)

2012-07-01T23:59:59.000Z

50

HYDRATE CORE DRILLING TESTS  

SciTech Connect

The ''Methane Hydrate Production from Alaskan Permafrost'' project is a three-year endeavor being conducted by Maurer Technology Inc. (MTI), Noble, and Anadarko Petroleum, in partnership with the U.S. DOE National Energy Technology Laboratory (NETL). The project's goal is to build on previous and ongoing R&D in the area of onshore hydrate deposition. The project team plans to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope includes drilling and coring one well on Anadarko leases in FY 2003 during the winter drilling season. A specially built on-site core analysis laboratory will be used to determine some of the physical characteristics of the hydrates and surrounding rock. Prior to going to the field, the project team designed and conducted a controlled series of coring tests for simulating coring of hydrate formations. A variety of equipment and procedures were tested and modified to develop a practical solution for this special application. This Topical Report summarizes these coring tests. A special facility was designed and installed at MTI's Drilling Research Center (DRC) in Houston and used to conduct coring tests. Equipment and procedures were tested by cutting cores from frozen mixtures of sand and water supported by casing and designed to simulate hydrate formations. Tests were conducted with chilled drilling fluids. Tests showed that frozen core can be washed out and reduced in size by the action of the drilling fluid. Washing of the core by the drilling fluid caused a reduction in core diameter, making core recovery very difficult (if not impossible). One successful solution was to drill the last 6 inches of core dry (without fluid circulation). These tests demonstrated that it will be difficult to capture core when drilling in permafrost or hydrates without implementing certain safeguards. Among the coring tests was a simulated hydrate formation comprised of coarse, large-grain sand in ice. Results with this core showed that the viscosity of the drilling fluid must also be carefully controlled. When coarse sand was being cored, the core barrel became stuck because the drilling fluid was not viscous enough to completely remove the large grains of sand. These tests were very valuable to the project by showing the difficulties in coring permafrost or hydrates in a laboratory environment (as opposed to a field environment where drilling costs are much higher and the potential loss of equipment greater). Among the conclusions reached from these simulated hydrate coring tests are the following: Frozen hydrate core samples can be recovered successfully; A spring-finger core catcher works best for catching hydrate cores; Drilling fluid can erode the core and reduces its diameter, making it more difficult to capture the core; Mud must be designed with proper viscosity to lift larger cuttings; and The bottom 6 inches of core may need to be drilled dry to capture the core successfully.

John H. Cohen; Thomas E. Williams; Ali G. Kadaster; Bill V. Liddell

2002-11-01T23:59:59.000Z

51

Modeling and Simulation of an Open Core Down-Draft Moving Bed Rice Husk Gasifier  

Science Journals Connector (OSTI)

Recently we developed a new type of open core moving bed rice husk gasifier for small scale application. Here, we...T rate of the rice husk was varied in the range of 50-300 kg/m2.h. and the air velocity from 50 ...

R. K. Manurung; A. A. C. M. Beenackers

1993-01-01T23:59:59.000Z

52

Growth of Smaller Grain Attached on Larger One: Algorithm to Overcome Unphysical Overlap between Grain  

E-Print Network (OSTI)

As a smaller grain, which is attached on larger one, is growing, it pushes also the larger one and other grains in its surrounding. In a simulation of similar system, repulsive force such as contact force based on linear spring-dashpot model can not accommodate this situation when cell growing rate is faster than simulation time step, since it produces sudden large overlap between grains that makes unphysical result. An algorithm that preserves system linear momentum by introducing additional velocity induced by cell growth is presented in this work. It should be performed in an implicit step. The algorithm has successfully eliminated unphysical overlap.

Acep Purqon; Sparisoma Viridi

2014-11-01T23:59:59.000Z

53

Creating geometry and mesh models for nuclear reactor core geometries using a lattice hierarchy-based approach.  

SciTech Connect

Nuclear reactor cores are constructed as rectangular or hexagonal lattices of assemblies, where each assembly is itself a lattice of fuel, control, and instrumentation pins, surrounded by water or other material that moderates neutron energy and carries away fission heat. We describe a system for generating geometry and mesh for these systems. The method takes advantage of information about repeated structures in both assembly and core lattices to simplify the overall process. The system allows targeted user intervention midway through the process, enabling modification and manipulation of models for meshing or other purposes. Starting from text files describing assemblies and core, the tool can generate geometry and mesh for these models automatically as well. Simple and complex examples of tool operation are given, with the latter demonstrating generation of meshes with 12 million hexahedral elements in less than 30 minutes on a desktop workstation, using about 4 GB of memory. The tool is released as open source software as part of the MeshKit mesh generation library.

Tautges, T. J.; Jain, R.; Mathematics and Computer Science

2010-01-01T23:59:59.000Z

54

Intrinsic reactivity feedback characteristics for safety analysis of heterogeneous and homogeneous LMFBR core designs  

SciTech Connect

This paper presents a comparison of the intrinsic reactivity feedback characteristics of homogeneous and heterogeneous LMFBR designs. The comparisons are shown for a 1000 MWth LMFBR core design. However, the applicability of the conclusions drawn from these comparisons are generic to larger LMFBRs. Consistent sodium void worth distributions have been calculated for heterogeneous and homogeneous 1000 MWth LMFBR core designs. The basic calculations were performed with three dimensional models using ENDF/B-III cross section data and first order perturbation theory.

Doncals, R.A.; Lake, J.A.

1982-01-01T23:59:59.000Z

55

SELF-CONSISTENT MODEL OF THE INTERSTELLAR PICKUP PROTONS, ALFVENIC TURBULENCE, AND CORE SOLAR WIND IN THE OUTER HELIOSPHERE  

SciTech Connect

A self-consistent model of the interstellar pickup protons, the slab component of the Alfvenic turbulence, and core solar wind (SW) protons is presented for r {>=} 1 along with the initial results of and comparison with the Voyager 2 (V2) observations. Two kinetic equations are used for the pickup proton distribution and Alfvenic power spectral density, and a third equation governs SW temperature including source due to the Alfven wave energy dissipation. A fraction of the pickup proton free energy, f{sub D} , which is actually released in the waveform during isotropization, is taken from the quasi-linear consideration without preexisting turbulence, whereas we use observations to specify the strength of the large-scale driving, C{sub sh}, for turbulence. The main conclusions of our study can be summarized as follows. (1) For C{sub sh} Almost-Equal-To 1-1.5 and f{sub D} Almost-Equal-To 0.7-1, the model slab component agrees well with the V2 observations of the total transverse magnetic fluctuations starting from {approx}8 AU. This indicates that the slab component at low-latitudes makes up a majority of the transverse magnetic fluctuations beyond 8-10 AU. (2) The model core SW temperature agrees well with the V2 observations for r {approx}> 20 AU if f{sub D} Almost-Equal-To 0.7-1. (3) A combined effect of the Wentzel-Kramers-Brillouin attenuation, large-scale driving, and pickup proton generated waves results in the energy sink in the region r {approx}< 10 AU, while wave energy is pumped in the turbulence beyond 10 AU. Without energy pumping, the nonlinear energy cascade is suppressed for r {approx}< 10 AU, supplying only a small energy fraction into the k-region of dissipation by the core SW protons. A similar situation takes place for the two-dimensional turbulence. (4) The energy source due to the resonant Alfven wave damping by the core SW protons is small at heliocentric distances r {approx}< 10 AU for both the slab and the two-dimensional turbulent components. As a result, adiabatic cooling mostly controls the model SW temperature in this region, and the model temperature disagrees with the V2 observations in the region r {approx}< 20 AU.

Gamayunov, Konstantin V.; Zhang Ming; Rassoul, Hamid K. [Department of Physics and Space Sciences, Florida Institute of Technology, Melbourne, FL 32901 (United States); Pogorelov, Nikolai V.; Heerikhuisen, Jacob, E-mail: kgamayunov@fit.edu [Department of Physics and Center for Space Physics and Aeronomic Research, University of Alabama, Huntsville, AL 35899 (United States)

2012-09-20T23:59:59.000Z

56

Dipolar origin of the gas-liquid coexistence of the hard-core 1:1 electrolyte model J. M. Romero-Enrique,1,  

E-Print Network (OSTI)

as a transition between two dimerized fluid phases. The role of the unpaired ions can be considered-liquid phase transition of hard-core 1:1 electrolyte models. We study a class of dipolar dimer models small values of Rc . This fact allows us to describe the gas-liquid transition in the free ion model

57

37-cell hollow-core-fiber designs with improved single-modedness  

Science Journals Connector (OSTI)

Simulations show that the PRISM strategy for suppression of higher-order modes can be applied broadly, to cores larger than 19-cell and core thicknesses larger than half the lattice...

Fini, John M; Mangan, Brian; Meng, Linli; Monberg, Eric M; Nicholson, Jeffrey W; Windeler, Robert S

58

Two-Dimensional Hydrodynamic Core-Collapse Supernova Simulations with Spectral Neutrino Transport II. Models for Different Progenitor Stars  

E-Print Network (OSTI)

1D and 2D supernova simulations for stars between 11 and 25 solar masses are presented, making use of the Prometheus/Vertex neutrino-hydrodynamics code, which employs a full spectral treatment of the neutrino transport. Multi-dimensional transport aspects are treated by the ``ray-by-ray plus'' approximation described in Paper I. Our set of models includes a 2D calculation for a 15 solar mass star whose iron core is assumed to rotate rigidly with an angular frequency of 0.5 rad/s before collapse. No important differences were found depending on whether random seed perturbations for triggering convection are included already during core collapse, or whether they are imposed on a 1D collapse model shortly after bounce. Convection below the neutrinosphere sets in about 40 ms p.b. at a density above 10**12 g/cm^3 in all 2D models, and encompasses a layer of growing mass as time goes on. It leads to a more extended proto-neutron star structure with accelerated lepton number and energy loss and significantly higher muon and tau neutrino luminosities, but reduced mean energies of the radiated neutrinos, at times later than ~100 ms p.b. In case of an 11.2 solar mass star we find that low (l = 1,2) convective modes cause a probably rather weak explosion by the convectively supported neutrino-heating mechanism after ~150 ms p.b. when the 2D simulation is performed with a full 180 degree grid, whereas the same simulation with 90 degree wedge fails to explode like all other models. This sensitivity demonstrates the proximity of our 2D models to the borderline between success and failure, and stresses the need of simulations in 3D, ultimately without the axis singularity of a polar grid. (abridged)

R. Buras; H. -Th. Janka; M. Rampp; K. Kifonidis

2005-12-07T23:59:59.000Z

59

Core - Corona Model analysis of the Low Energy Beam Scan at RHIC (Relativistic Heavy Ion Collider) in Brookhaven (USA)  

E-Print Network (OSTI)

The centrality dependence of spectra of identified particles in collisions between ultrarelativistic heavy ions with a center of mass energy ($\\sqrt{s}$) of 39 and 11.5 $AGeV$ is analyzed in the core - corona model. We show that at these energies the spectra can be well understood assuming that they are composed of two components whose relative fraction depends on the centrality of the interaction: The core component which describes an equilibrated quark gluon plasma and the corona component which is caused by nucleons close to the surface of the interaction zone which scatter only once and which is identical to that observed in proton-proton collisions. The success of this approach at 39 and 11.5 $AGeV$ shows that the physics does not change between this energy and $\\sqrt{s}=200~ AGeV$ for which this model has been developed (Aichelin 2008). This presents circumstantial evidence that a quark gluon plasma is also created at center of mass energies as low as 11.5 $AGeV$.

M. Gemard; J. Aichelin

2014-02-02T23:59:59.000Z

60

Core Specialization  

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

Core Specialization Core Specialization Core Specialization Core Specialization (CS) is a feature of the Cray operating system that allows the user to reserve one or more cores per node for handling system services, and thus reduce the effects of timing jitter due to interruptions from the operating system at the expense of (possibly) requiring more nodes to run an application. The specialized cores may also be used in conjunction with Cray's MPI asynchronous progress engine [1] to improve the overlap of communication and computation for applications that use non-blocking MPI functions. In the absence of CS, the compute cores must service their own non-blocking calls. Hyper-Threading complicates questions abouty the most effective use of processor resources. HT doubles the number of compute stream (i.e.

Note: This page contains sample records for the topic "larger core models" 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

Core Specialization  

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

Core Core Specialization Core Specialization Core Specialization (CS) is a feature of the Cray operating system that allows the user to reserve one or more cores per node for handling system services, and thus reduce the effects of timing jitter due to interruptions from the operating system at the expense of (possibly) requiring more nodes to run an application. The specialized cores may also be used in conjunction with Cray's MPI asynchronous progress engine [1] to improve the overlap of communication and computation for applications that use non-blocking MPI functions. In the absence of CS, the compute cores must service their own non-blocking calls. Hyper-Threading complicates questions abouty the most effective use of processor resources. HT doubles the number of compute stream (i.e.

62

Modeling of fuel-to-steel heat transfer in core disruptive accidents  

E-Print Network (OSTI)

A mathematical model for direct-contact boiling heat transfer between immiscible fluids was developed and tested experimentally. The model describes heat transfer from a hot fluid bath to an ensemble of droplets of a cooler ...

Smith, Russell Charles

1980-01-01T23:59:59.000Z

63

Neutron scattering studies and modeling of high mobility group 14 core nucleosome complex  

Science Journals Connector (OSTI)

Neutron scattering studies and modeling of high mobility...were studied by use of small-angle neutron scattering techniques. By varying the H2O...occurring in active nucleosomes. Neutron scattering studies and modeling of high mobility...

E C Uberbacher; J K Mardian; R M Rossi; D E Olins; G J Bunick

1982-01-01T23:59:59.000Z

64

Functional reliability evaluation of an MTR-pool type research reactor core using the load–capacity interference model  

Science Journals Connector (OSTI)

Abstract This paper presents the functional reliability evaluation of Tehran Research Reactor (TRR) core in normal operation. The concept of functional reliability, borrowed from reliability physics, uses the well-known resistance–stress or load–capacity interference model that is used in the structural reliability framework. To use the load–capacity interference model, uncertainties of significant parameters in system performance are propagated into system dynamics modeled with RELAP5/Mod 3.2 using Latin Hypercube Sampling (LHS) method and exceedance probability (EP) model is used as quantification method. The proposed method in this paper solves a common problem in reliability analysis, i.e., lack of sufficient failure data in specific operating conditions. Although defining failure criteria in normal operation are difficult, this paper focuses on the application of multiple states criteria to determine the status of a system. The status of the reactor core in normal operation is considered multiple states regarding to a performance representative parameter that is temperature in this work. Outlet temperatures of fuel hot and average channels were selected to be performance indicators in normal operation. Consulting with TRR engineers and operators as well as safety analysis report, two failure states were considered exceeding 65.1 °C and 58.9 °C for the hot channel and 50.4 °C and 45.6 °C for the average channel as upper and lower limits respectively. The calculated reliability was 9.1e?01 with 95% of confidence interval, which is in good agreement with experimental results. Using sensitivity analysis in input parameters, it was concluded that the value of the heat transfer coefficient parameter in fuel has the most significant effect on the results.

Ramin Barati; Saeed Setayeshi

2013-01-01T23:59:59.000Z

65

SciTech Connect: Development of a land ice core for the Model...  

Office of Scientific and Technical Information (OSTI)

AC52-06NA25396 Resource Type: Conference Resource Relation: Conference: Community Earth System Model Workshop ; 2012-06-18 - 2012-06-21 ; Breckenridge, Colorado, United...

66

Broad bounds on Earth's accretion and core formation constrained by geochemical models  

E-Print Network (OSTI)

accretion at either 301,5 or 1002,3 Myr after solar system formation. These models as- sume full metal. Impacts of numerous Moon- to Mars-sized planetary embryos on the growing Earth re- leased sufficient

Rudge, John

67

Photovoltages Larger than the Band Gap in Thin Films of Germanium  

Science Journals Connector (OSTI)

Photovoltages much larger than the band gap were investigated in thin films of germanium deposited obliquely onto Pyrex substrates. The voltages were studied as functions of angle of deposit film thickness intensity of illumination temperature and ambient atmosphere. A model is presented which explains the following observations. Positive and negative photovoltages exist simultaneously in a single sample; which of these predominates changes with time. Dark resistance and photovoltage exhibit the same temperature dependence with identical activation energies indicating that both dark resistance and photovoltage arise from the same elementary processes.

H. Kallmann; G. Marmor Spruch; S. Trester

1972-01-01T23:59:59.000Z

68

Diffusion modeling of fission product release during depressurized core conduction cooldown conditions  

SciTech Connect

A simple model for diffusion through the silicon carbide layer of TRISO particles is applied to the data for accident condition testing of fuel spheres for the High-Temperature Reactor program of the Federal Republic of Germany (FRG). Categorization of sphere release of {sup 137}Cs based on fast neutron fluence permits predictions of release with an accuracy comparable to that of the US/FRG accident condition fuel performance model. Calculations are also performed for {sup 85}Kr, {sup 90}Sr, and {sup 110m}Ag. Diffusion of cesium through SiC suggests that models of fuel failure should consider fuel performance during repeated accident condition thermal cycling. Microstructural considerations in models in fission product release are discussed. The neutron-induced segregation of silicon within the SiC structure is postulated as a mechanism for enhanced fission product release during accident conditions. An oxygen-enhanced SiC decomposition mechanism is also discussed. 12 refs., 11 figs., 2 tabs.

Martin, R.C.

1990-01-01T23:59:59.000Z

69

Two-dimensional core-softened model with water like properties. Study by thermodynamic perturbation theory  

E-Print Network (OSTI)

Thermodynamic properties of the particles interacting through smooth version of Stell-Hemmer interaction were studied using Wertheim's thermodynamic perturbation theory. The temperature dependence of molar volume, heat capacity, isothermal compressibility and thermal expansion coefficient at constant pressure for different number of bonding sites on particle were evaluated. The model showed water-like anomalies for all evaluated quantities, but thermodynamic perturbation theory does not properly predict the dependence of these properties at a fixed number of bonding points.

T. Urbic

2013-12-16T23:59:59.000Z

70

Continuum-kinetic-microscopic model of lung clearance due to core-annular fluid entrainment  

SciTech Connect

The human lung is protected against aspirated infectious and toxic agents by a thin liquid layer lining the interior of the airways. This airway surface liquid is a bilayer composed of a viscoelastic mucus layer supported by a fluid film known as the periciliary liquid. The viscoelastic behavior of the mucus layer is principally due to long-chain polymers known as mucins. The airway surface liquid is cleared from the lung by ciliary transport, surface tension gradients, and airflow shear forces. This work presents a multiscale model of the effect of airflow shear forces, as exerted by tidal breathing and cough, upon clearance. The composition of the mucus layer is complex and variable in time. To avoid the restrictions imposed by adopting a viscoelastic flow model of limited validity, a multiscale computational model is introduced in which the continuum-level properties of the airway surface liquid are determined by microscopic simulation of long-chain polymers. A bridge between microscopic and continuum levels is constructed through a kinetic-level probability density function describing polymer chain configurations. The overall multiscale framework is especially suited to biological problems due to the flexibility afforded in specifying microscopic constituents, and examining the effects of various constituents upon overall mucus transport at the continuum scale.

Mitran, Sorin, E-mail: mitran@unc.edu

2013-07-01T23:59:59.000Z

71

Thermal modeling of core sampling in flammable gas waste tanks. Part 2: Rotary-mode sampling  

SciTech Connect

The radioactive waste stored in underground storage tanks at Hanford site includes mixtures of sodium nitrate and sodium nitrite with organic compounds. The waste can produce undesired violent exothermic reactions when heated locally during the rotary-mode sampling. Experiments are performed varying the downward force at a maximum rotational speed of 55 rpm and minimum nitrogen purge flow of 30 scfm. The rotary drill bit teeth-face temperatures are measured. The waste is simulated with a low thermal conductivity hard material, pumice blocks. A torque meter is used to determine the energy provided to the drill string. The exhaust air-chip temperature as well as drill string and drill bit temperatures and other key operating parameters were recorded. A two-dimensional thermal model is developed. The safe operating conditions were determined for normal operating conditions. A downward force of 750 at 55 rpm and 30 scfm nitrogen purge flow was found to yield acceptable substrate temperatures. The model predicted experimental results reasonably well. Therefore, it could be used to simulate abnormal conditions to develop procedures for safe operations.

Unal, C.; Poston, D.; Pasamehmetoglu, K.O. [Los Alamos National Lab., NM (United States). Nuclear Systems Design and Analysis Group; Witwer, K.S. [Westinghouse Hanford Co., Richland, WA (United States). Engineering Testing Lab.

1997-08-01T23:59:59.000Z

72

Core-based evidence for sandy slump and sandy debris flow facies in the Pliocene and Pleistocene of the Gulf of Mexico: Implications for submarine fan models  

SciTech Connect

Examination of nearly 3,500 feet of conventional core from Pliocene and Pleistocene deep-water reservoirs cored in 25 wells in 8 different areas covering the eastern, central and western Gulf of Mexico reveals that the reservoirs are predominantly composed of mass-transport deposits, mainly sandy slumps and sandy debris flows (60-100% of cored intervals). Bottom-current reworked sands are common (10-50%). Of importance to existing submarine fan models is that turbidities are extremely rare (<1 % of all cores). Sedimentary features indicative of slump and debris-flow origin include sand units with sharp upper contacts, slump folds, discordant, steeply dipping layers (up to 60[degrees]), glide planes, shear zones, brecciated clasts, rafted mudstone clasts, planar clast fabric, inverse grading of clasts, and moderate-to-high matrix content (5-20 %). These reservoirs have been interpreted by others to represent turbidite-dominated basin-floor fans and slope fans of the often used sequence stratigraphic model. However, our core data do not show a dominance of turbidities. Sandy debris flows exhibit a variety of log motifs (e.g., blocky, fining-up, and coarsening-up) due to changes in concentration of midstone clasts, and a variety of internal seismic facies (e.g., parallel-continuous, irregular-discontinuous, chaotic -discontinuous, and lateral pinch out) perhaps due to changes in stacking patterns of debris flows and slumps. Classic submarine-fan models, commonly advocated for these reservoirs, may not be appropriate. We propose a slump and debris-flow, dominated slope model in which sea-floor topography and depositional freezing (i.e., plastic flows) control sand distribution and geometry. Contrary to popular belief, sandy debris flows can be thick, areally extensive, and excellent reservoirs.

Shanmugam, G. (Mobil Exploration and Producing Technical Center, Dallas, TX (United States)); Zimbrick, G. (Mobil Exploration and Producing U.S., Dallas, TX (United States))

1996-01-01T23:59:59.000Z

73

Core-based evidence for sandy slump and sandy debris flow facies in the Pliocene and Pleistocene of the Gulf of Mexico: Implications for submarine fan models  

SciTech Connect

Examination of nearly 3,500 feet of conventional core from Pliocene and Pleistocene deep-water reservoirs cored in 25 wells in 8 different areas covering the eastern, central and western Gulf of Mexico reveals that the reservoirs are predominantly composed of mass-transport deposits, mainly sandy slumps and sandy debris flows (60-100% of cored intervals). Bottom-current reworked sands are common (10-50%). Of importance to existing submarine fan models is that turbidities are extremely rare (<1 % of all cores). Sedimentary features indicative of slump and debris-flow origin include sand units with sharp upper contacts, slump folds, discordant, steeply dipping layers (up to 60{degrees}), glide planes, shear zones, brecciated clasts, rafted mudstone clasts, planar clast fabric, inverse grading of clasts, and moderate-to-high matrix content (5-20 %). These reservoirs have been interpreted by others to represent turbidite-dominated basin-floor fans and slope fans of the often used sequence stratigraphic model. However, our core data do not show a dominance of turbidities. Sandy debris flows exhibit a variety of log motifs (e.g., blocky, fining-up, and coarsening-up) due to changes in concentration of midstone clasts, and a variety of internal seismic facies (e.g., parallel-continuous, irregular-discontinuous, chaotic -discontinuous, and lateral pinch out) perhaps due to changes in stacking patterns of debris flows and slumps. Classic submarine-fan models, commonly advocated for these reservoirs, may not be appropriate. We propose a slump and debris-flow, dominated slope model in which sea-floor topography and depositional freezing (i.e., plastic flows) control sand distribution and geometry. Contrary to popular belief, sandy debris flows can be thick, areally extensive, and excellent reservoirs.

Shanmugam, G. [Mobil Exploration and Producing Technical Center, Dallas, TX (United States); Zimbrick, G. [Mobil Exploration and Producing U.S., Dallas, TX (United States)

1996-12-31T23:59:59.000Z

74

Modeling and analysis framework for core damage propagation during flow-blockage-initiated accidents in the Advanced Neutron Source Reactor at Oak Ridge National Laboratory  

SciTech Connect

This paper describes modeling and analysis to evaluate the extent of core damage during flow blockage events in the Advanced Neutron Source (ANS) reactor planned to be built at the Oak Ridge National Laboratory (ORNL). Damage propagation is postulated to occur from thermal conduction between damaged and undamaged plates due to direct thermal contact. Such direct thermal contact may occur because of fuel plate swelling during fission product vapor release or plate buckling. Complex phenomena of damage propagation were modeled using a one-dimensional heat transfer model. A scoping study was conducted to learn what parameters are important for core damage propagation, and to obtain initial estimates of core melt mass for addressing recriticality and steam explosion events. The study included investigating the effects of the plate contact area, the convective heat transfer coefficient, thermal conductivity upon fuel swelling, and the initial temperature of the plate being contacted by the damaged plate. Also, the side support plates were modeled to account for their effects on damage propagation. The results provide useful insights into how various uncertain parameters affect damage propagation.

Kim, S.H.; Taleyarkhan, R.P.; Navarro-Valenti, S.; Georgevich, V.

1995-09-01T23:59:59.000Z

75

Absorption spectra of CdSe-ZnS core-shell quantum dots at high photon energies : experiment and modeling  

E-Print Network (OSTI)

Absorption spectra of CdSe-ZnS core-shell quantum dots at high photon energies : experiment Tata Institute of Fundamental Research Homi Bhabha Road, Mumbai 400005, India Abstract Absorption. In agreement with previous reports, the absorption coefficient at energies 1 eV above the effective bandgap

Ghosh, Sandip

76

Large-scale Renewable Energy Projects (Larger than 10 MWs) | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Large-scale Renewable Energy Projects (Larger than 10 MWs) Large-scale Renewable Energy Projects (Larger than 10 MWs) Large-scale Renewable Energy Projects (Larger than 10 MWs) October 7, 2013 - 9:32am Addthis Renewable energy projects larger than 10 megawatts (MW) are complex and typically require private-sector financing. The Federal Energy Management Program (FEMP) developed a guide to help Federal agencies, and the developers and financiers that work with them, to successfully install these projects at Federal facilities. The Large-Scale Renewable Energy Guide: Developing Renewable Energy Projects Larger than 10 MWs at Federal Facilities: A Practical Guide to Getting Large-Scale Renewable Energy Projects Financed with Private Capital provides a framework to allow the Federal Government, private developers, and financiers to work in a

77

Modeling and analysis framework for core damage propagation during flow-blockage-initiated accidents in the Advanced Neutron Source reactor at Oak Ridge National Laboratory  

SciTech Connect

This paper describes modeling and analysis to evaluate the extent of core damage during flow blockage events in the Advanced Neutron Source (ANS) reactor planned to be built at ORNL. Damage propagation is postulated to occur from thermal conduction between dmaged and undamaged plates due to direct thermal contact. Such direct thermal contact may occur beause of fuel plate swelling during fission product vapor release or plate buckling. Complex phenomena of damage propagation were modeled using a one-dimensional heat transfer model. A parametric study was done for several uncertain variables. The study included investigating effects of plate contact area, convective heat transfer coefficient, thermal conductivity on fuel swelling, and initial temperature of the plate being contacted by the damaged plate. Also, the side support plates were modeled to account for their effects of damage propagation. Results provide useful insights into how variouss uncertain parameters affect damage propagation.

Kim, S.H.; Taleyarkhan, R.P.; Navarro-Valenti, S.; Georgevich, V.

1995-12-31T23:59:59.000Z

78

New Report Shows Trend Toward Larger Offshore Wind Systems, with 11  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Report Shows Trend Toward Larger Offshore Wind Systems, with 11 Report Shows Trend Toward Larger Offshore Wind Systems, with 11 Advanced Stage Projects Proposed in U.S. Waters New Report Shows Trend Toward Larger Offshore Wind Systems, with 11 Advanced Stage Projects Proposed in U.S. Waters October 23, 2013 - 10:52am Addthis The Energy Department today released a new report showing progress for the U.S. offshore wind energy market in 2012, including the completion of two commercial lease auctions for federal Wind Energy Areas and 11 commercial-scale U.S. projects representing over 3,800 megawatts (MW) of capacity reaching an advanced stage of development. Further, the report highlights global trends toward building offshore turbines in deeper waters and using larger, more efficient turbines in offshore wind farms, increasing the amount of electricity delivered to consumers.

79

Ionic Liquid Pretreatment Process for Biomass Is Successfully Implemented at Larger Scale  

Office of Energy Efficiency and Renewable Energy (EERE)

DOE-funded researchers have shown that a new, highly effective pretreatment process used in the production of biofuel can be executed at a larger scale than ever achieved before.

80

Effects of CSP Support Particle Size on the Performance of Larger Diameter Liquid Partition Columns  

Science Journals Connector (OSTI)

......research-article Editorial Effects of CSP Support Particle Size on the Performance...packed with different particle sizes of CSP (controlled surface porosity) support...larger, infinite-diameter columns and CSP support used in this study. Reduced plate......

H. C. Beachell; J. J. DeStefano

1972-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

Steady- and transient-state analyses of fully ceramic microencapsulated fuel loaded reactor core via two-temperature homogenized thermal-conductivity model  

Science Journals Connector (OSTI)

Abstract Fully ceramic microencapsulated (FCM) fuel, a type of accident-tolerant fuel (ATF), consists of TRISO particles randomly dispersed in a SiC matrix. In this study, for a thermal analysis of the FCM fuel with such a high heterogeneity, a two-temperature homogenized thermal-conductivity model was applied by the authors. This model provides separate temperatures for the fuel-kernels and the SiC matrix. It also provides more realistic temperature profiles than those of harmonic- and volumetric-average thermal conductivity models, which are used for thermal analysis of a fuel element in \\{VHTRs\\} having a composition similar to the FCM fuel, because such models are unable to provide the fuel-kernel and graphite matrix temperatures separately. In this study, coupled with a neutron diffusion model, a FCM fuel-loaded reactor core is analyzed via a two-temperature homogenized thermal-conductivity model at steady- and transient-states. The results are compared to those from harmonic- and volumetric-average thermal conductivity models, i.e., we compare keff eigenvalues, power distributions, and temperature profiles in the hottest single-channel at steady-state. At transient-state, we compare total powers, reactivity, and maximum temperatures in the hottest single-channel obtained by the different thermal analysis models. The different thermal analysis models and the availability of fuel-kernel temperatures in the two-temperature homogenized thermal-conductivity model for Doppler temperature feedback cause significant differences as revealed by comparisons.

Yoonhee Lee; Nam Zin Cho

2015-01-01T23:59:59.000Z

82

Using CORE Model-Based Systems Engineering Software to Support Program Management in the U.S. Department of Energy Office of the Biomass Project: Preprint  

SciTech Connect

This paper describes how a model-based systems engineering software, CORE, is helping the U. S. Department of Energy's Office of Biomass Program assist with bringing biomass-derived biofuels to the market. This software tool provides information to guide informed decision-making as biomass-to-biofuels systems are advanced from concept to commercial adoption. It facilitates management and communication of program status by automatically generating custom reports, Gantt charts, and tables using the widely available programs of Microsoft Word, Project and Excel.

Riley, C.; Sandor, D.; Simpkins, P.

2006-11-01T23:59:59.000Z

83

Microsoft Word - IronCore  

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

November/December 2013 November/December 2013 Percolation Explains How Earth's Iron Core Formed The formation of Earth's metallic core, which makes up a third of our planet's mass, represents the most significant differentiation event in Earth's history. Earth's present layered structure with a metallic core and an overlying silicate mantle would have required mechanisms to separate iron alloy from a silicate phase. Percolation of liquid iron alloy moving through a solid silicate matrix (much as water percolates through porous rock, or even coffee grinds) has been proposed as a possible model for core formation (Figure 1). Many previous experimental results have ruled out percolation as a major core formation mechanism for Earth at the relatively lower pressure conditions in the upper mantle, but

84

EARLIEST STAGES OF PROTOCLUSTER FORMATION: SUBSTRUCTURE AND KINEMATICS OF STARLESS CORES IN ORION  

SciTech Connect

We study the structure and kinematics of nine 0.1 pc scale cores in Orion with the IRAM 30 m telescope and at higher resolution eight of the cores with CARMA, using CS(2-1) as the main tracer. The single-dish moment zero maps of the starless cores show single structures with central column densities ranging from 7 to 42 Multiplication-Sign 10{sup 23} cm{sup -2} and LTE masses from 20 M{sub Sun} to 154 M{sub Sun }. However, at the higher CARMA resolution (5''), all of the cores except one fragment into 3-5 components. The number of fragments is small compared to that found in some turbulent fragmentation models, although inclusion of magnetic fields may reduce the predicted fragment number and improve the model agreement. This result demonstrates that fragmentation from parsec-scale molecular clouds to sub-parsec cores continues to take place inside the starless cores. The starless cores and their fragments are embedded in larger filamentary structures, which likely played a role in the core formation and fragmentation. Most cores show clear velocity gradients, with magnitudes ranging from 1.7 to 14.3 km s{sup -1} pc{sup -1}. We modeled one of them in detail, and found that its spectra are best explained by a converging flow along a filament toward the core center; the gradients in other cores may be modeled similarly. We infer a mass inflow rate of {approx}2 Multiplication-Sign 10{sup -3} M{sub Sun} yr{sup -1}, which is in principle high enough to overcome radiation pressure and allow for massive star formation. However, the core contains multiple fragments, and it is unclear whether the rapid inflow would feed the growth of primarily a single massive star or a cluster of lower mass objects. We conclude that fast, supersonic converging flow along filaments play an important role in massive star and cluster formation.

Lee, Katherine; Looney, Leslie W. [Department of Astronomy, University of Illinois, Urbana, IL 61801 (United States); Schnee, Scott [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Li Zhiyun [Astronomy Department, University of Virginia, Charlottesville, VA 22904 (United States)

2013-08-01T23:59:59.000Z

85

Maternal support in early childhood predicts larger hippocampal volumes at school age  

E-Print Network (OSTI)

responses, and larger hippocampal volumes in developing animals. In humans, a relation- ship between effect of maternal support on hippocampal volumes was greater in nondepressed children. These findings provide prospective evidence in humans of the positive effect of early supportive parenting on healthy

86

Advanced BWR core component designs and the implications for SFD analysis  

SciTech Connect

Prior to the DF-4 boiling water reactor (BWR) severe fuel damage (SFD) experiment conducted at the Sandia National Laboratories in 1986, no experimental data base existed for guidance in modeling core component behavior under postulated severe accident conditions in commercial BWRs. This paper will present the lessons learned from the DF-4 experiment (and subsequent German CORA BWR SFD tests) and the impact on core models in the current generation of SFD codes. The DF-4 and CORA BWR test assemblies were modeled on the core component designs circa 1985; that is, the 8 x 8 fuel assembly with two water rods and a cruciform control blade constructed of B{sub 4}C-filled tubelets. Within the past ten years, the state-of-the-art with respect to BWR core component development has out-distanced the current SFD experimental data base and SFD code capabilities. For example, modern BWR control blade design includes hafnium at the tips and top of each control blade wing for longer blade operating lifetimes; also water rods have been replaced by larger water channels for better neutronics economy; and fuel assemblies now contain partial-length fuel rods, again for better neutronics economy. This paper will also discuss the implications of these advanced fuel assembly and core component designs on severe accident progression and on the current SFD code capabilities.

Ott, L.J.

1997-02-01T23:59:59.000Z

87

Core Capabilities | Argonne National Laboratory  

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

The Advanced Photon Source is one of the brightest sources of X-rays in the The Advanced Photon Source is one of the brightest sources of X-rays in the Western Hemisphere. Photons are accelerated to over 99% of the speed of light around its ring, which is the size of a baseball stadium. To view a larger version of the image, click on it. The Center for Nanoscale Materials at Argonne is a premier user facility, providing expertise, instruments, and infrastructure for interdisciplinary nanoscience and nanotechnology research. To view a larger version of the image, click on it. Core Capabilities Argonne's vision is to lead the world in discovery science and engineering that provides technical solutions to the grand challenges of our time. Argonne's vision is to lead the world in discovery science and engineering that provides technical solutions to the grand challenges of our time:

88

Interplay of Neutrino Opacities in Core-collapse Supernova Simulations  

SciTech Connect

We have conducted a series of numerical experiments using spherically symmetric, general relativistic, neutrino radiation hydrodynamics with the code Agile-BOLTZTRAN to examine the effects of including, and improving, the calculation of neutrino opacities on the development of supernova simulations by removing, or replacing, each opacity individually, or removing opacities in groups. We find that during core collapse improvements to electron capture (EC) on nuclei, namely EC on an ensemble of nuclei based on the hybrid model, relative to the simpler independent-particle approximation (IPA) for a mean nucleus, plays the most important role of all tested neutrino opacities. Low-energy neutrinos emitted by nuclear EC preferentially escape during collapse leading to larger deleptonization of the collapsing core, without the energy downscattering via non-isoenergetic scattering (NIS) on electrons required for the models with IPA nuclear EC. During shock breakout the primary influence on the emergent neutrinos arises from NIS on electrons. For the accretion phase NIS on free nucleons and pair emission by $e^+e^-$-annihilation have the largest impact on the neutrino emission and shock evolution. Other opacities evaluated including nucleon-nucleon bremsstrahlung and especially neutrino-positron scattering have little measurable impact on neutrino emission or shock dynamics. Modern treatments of nuclear electron capture, $e^+e^-$-annihilation pair emission, and non-isoenergetic scattering on electrons and free nucleons are critical elements of core-collapse simulations of all dimensionality.

Lentz, Eric J [ORNL; Mezzacappa, Anthony [ORNL; Messer, Bronson [ORNL; Hix, William Raphael [ORNL; Bruenn, S. W. [Florida Atlantic University

2012-01-01T23:59:59.000Z

89

Multi-Group Formulation of the Temperature-Dependent Resonance Scattering Model and its Impact on Reactor Core Parameters  

SciTech Connect

A multi-group formulation for the exact neutron elastic scattering kernel is developed. It incorporates the neutron up-scattering effects, stemming from lattice atoms thermal motion and accounts for it within the resulting effective nuclear cross-section data. The effects pertain essentially to resonant scattering off of heavy nuclei. The formulation, implemented into a standalone code, produces effective nuclear scattering data that are then supplied directly into the DRAGON lattice physics code where the effects on Doppler Reactivity and neutron flux are demonstrated. The correct accounting for the crystal lattice effects influences the estimated values for the probability of neutron absorption and scattering, which in turn affect the estimation of core reactivity and burnup characteristics. The results show an increase in values of Doppler temperature feedback coefficients up to -10% for UOX and MOX LWR fuels compared to the corresponding values derived using the traditional asymptotic elastic scattering kernel. This paper also summarizes the results done on this topic to date.

Shadi Z. Ghrayeb [Pennsylvania State Univ., University Park, PA (United States). Dept. of Mechanical and Nuclear Engineering; Abderrafi M. Ougouag [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Mohamed Ouisloumen [Westinghouse Electric Company, Cranberry Township, PA (United States); Kostadin N. Ivanov [Pennsylvania State Univ., University Park, PA (United States). Dept. of Mechanical and Nuclear Engineering

2014-01-01T23:59:59.000Z

90

A turbulent MHD model for molecular clouds and a new method of accretion on to star-forming cores  

Science Journals Connector (OSTI)

......research-article Papers A turbulent MHD model for molecular clouds and...accretion, accretion discs|MHD|stars: formation|ISM: clouds...pre-main-sequence track on the HR diagram (Stahler, Shu Taam 1980...self-gravitating magnetohydrodynamic (MHD) fluid undergoing turbulence......

D. Balsara; D. Ward-Thompson; R.M. Crutcher

2001-11-01T23:59:59.000Z

91

Description of the Weatherization Assistance Program in larger multifamily buildings for Program Year 1989  

SciTech Connect

The efforts of the US Department of Energy (DOE) Weatherization Assistance Program (the Program) in larger multifamily buildings were examined for Program Year 1989. The results show that about 20,000 dwellings in these multifamily buildings were served under the Program that year. This is 9% of the total number of units served nationally, while costs were 7% of total national costs. High levels of activity in larger multifamily buildings were reported for some States, with New York accounting for half of all the residences treated. Owner investment is an important strategy in New York for improving their efforts. A wide range of measures was installed, but the materials costs for the measures are dominated by the cost of windows (80% of the total for that year). Where the whole building was treated, $561 was invested per unit, while for partial-building work the total invested was $417. The energy savings and cost effectiveness of the Program were not estimated, because energy use and cost data adequate for developing such estimates could not be obtained.

MacDonald, J.M.

1993-04-01T23:59:59.000Z

92

Developing a consensus-driven, core competency model to shape future audio engineering technology curriculum| A web-based modified Delphi study.  

E-Print Network (OSTI)

?? The purpose of this online study was to create a ranking of essential core competencies and technologies required by AET (audio engineering technology) programs… (more)

Tough, David T.

2010-01-01T23:59:59.000Z

93

4? Noncoplanar Stereotactic Body Radiation Therapy for Centrally Located or Larger Lung Tumors  

SciTech Connect

Purpose: To investigate the dosimetric improvements in stereotactic body radiation therapy for patients with larger or central lung tumors using a highly noncoplanar 4? planning system. Methods and Materials: This study involved 12 patients with centrally located or larger lung tumors previously treated with 7- to 9-field static beam intensity modulated radiation therapy to 50 Gy. They were replanned using volumetric modulated arc therapy and 4? plans, in which a column generation method was used to optimize the beam orientation and the fluence map. Maximum doses to the heart, esophagus, trachea/bronchus, and spinal cord, as well as the 50% isodose volume, the lung volumes receiving 20, 10, and 5 Gy were minimized and compared against the clinical plans. A dose escalation study was performed to determine whether a higher prescription dose to the tumor would be achievable using 4? without violating dose limits set by the clinical plans. The deliverability of 4? plans was preliminarily tested. Results: Using 4? plans, the maximum heart, esophagus, trachea, bronchus and spinal cord doses were reduced by 32%, 72%, 37%, 44%, and 53% (P?.001), respectively, and R{sub 50} was reduced by more than 50%. Lung V{sub 20}, V{sub 10}, and V{sub 5} were reduced by 64%, 53%, and 32% (P?.001), respectively. The improved sparing of organs at risk was achieved while also improving planning target volume (PTV) coverage. The minimal PTV doses were increased by the 4? plans by 12% (P=.002). Consequently, escalated PTV doses of 68 to 70 Gy were achieved in all patients. Conclusions: We have shown that there is a large potential for plan quality improvement and dose escalation for patients with larger or centrally located lung tumors using noncoplanar beams with sufficient quality and quantity. Compared against the clinical volumetric modulated arc therapy and static intensity modulated radiation therapy plans, the 4? plans yielded significantly and consistently improved tumor coverage and critical organ sparing. Given the known challenges in central structure dose constraints in stereotactic body radiation therapy to the lung, 4? planning may increase efficacy and reduce toxicity.

Dong, Peng; Lee, Percy; Ruan, Dan [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States)] [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States); Long, Troy; Romeijn, Edwin [Department of Industrial and Operations Engineering, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Industrial and Operations Engineering, University of Michigan, Ann Arbor, Michigan (United States); Low, Daniel A.; Kupelian, Patrick; Abraham, John; Yang, Yingli [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States)] [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States); Sheng, Ke, E-mail: ksheng@mednet.ucla.edu [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States)] [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States)

2013-07-01T23:59:59.000Z

94

The National Energy Modeling System: An Overview 2000 - Macroeconomic  

Gasoline and Diesel Fuel Update (EIA)

Macroeconomic assessment at EIA involves several modes of analysis. The first type of analysis, used in forecasting the Annual Energy Outlook where energy prices change, uses kernel regression and response surface techniques to mimic the response of larger macroeconomic and industrial models. This mode of analysis requires a given economic baseline and then calculates the economic impacts of changing energy prices, calculated from the chosen growth path. The economic growth cases are derived from the larger core models and can reflect either high, low, or reference case growth assumptions. Analyzing economic impacts from energy price changes uses the macroeconomic activity module (MAM) within NEMS and provides a subset of the macroeconomic variables available in the larger core models. The composition of the subset is determined by the other energy modules in NEMS, as they use various macroeconomic concepts as assumptions to their particular energy model.

95

Core Drilling Demonstration  

Energy.gov (U.S. Department of Energy (DOE))

Tank Farms workers demonstrate core drilling capabilities for Hanford single-shell tanks. Core drilling is used to determine the current condition of each tank to assist in the overall assessment...

96

NMR Structure Determination for Larger Proteins Using Backbone-Only Data  

Science Journals Connector (OSTI)

...Zimmerman D. E. ., Automated analysis of protein...Montelione G. T. , Automated analysis of protein...interface for evaluating automated probabilistic peak...A web server for rapid NMR-based protein...protein structure modeling methodology...Proteins | Computer Simulation Models, Molecular...

Srivatsan Raman; Oliver F. Lange; Paolo Rossi; Michael Tyka; Xu Wang; James Aramini; Gaohua Liu; Theresa A. Ramelot; Alexander Eletsky; Thomas Szyperski; Michael A. Kennedy; James Prestegard; Gaetano T. Montelione; David Baker

2010-02-19T23:59:59.000Z

97

Weak locking capacity of quantum channels can be much larger than private capacity  

E-Print Network (OSTI)

We show that it is possible for the so-called weak locking capacity of a quantum channel [Guha et al., PRX 4:011016, 2014] to be much larger than its private capacity. Both reflect different ways of capturing the notion of reliable communication via a quantum system while leaking almost no information to an eavesdropper; the difference is that the latter imposes an intrinsically quantum security criterion whereas the former requires only a weaker, classical condition. The channels for which this separation is most straightforward to establish are the complementary channels of classical-quantum (cq-)channels, and hence a subclass of Hadamard channels. We also prove that certain symmetric channels (related to photon number splitting) have positive weak locking capacity in the presence of a vanishingly small pre-shared secret, whereas their private capacity is zero. These findings are powerful illustrations of the difference between two apparently natural notions of privacy in quantum systems, relevant also to quantum key distribution (QKD): the older, naive one based on accessible information, contrasting with the new, composable one embracing the quantum nature of the eavesdropper's information. Assuming an additivity conjecture for constrained minimum output Renyi entropies, the techniques of the first part demonstrate a single-letter formula for the weak locking capacity of complements to cq-channels, coinciding with a general upper bound of Guha et al. for these channels. Furthermore, still assuming this additivity conjecture, this upper bound is given an operational interpretation for general channels as the maximum weak locking capacity of the channel activated by a suitable noiseless channel.

Andreas Winter

2014-03-25T23:59:59.000Z

98

Models of the Earth's Core  

Science Journals Connector (OSTI)

...the freezing point of water). However, this...iron in any plausible condensation from the solar nebula...theory) Parameter atmospheric P = 1.5 Mbar, P...continental geology, atmospheric chemistry, meteorology...continental geol-ogy, atmospheric chemistry, meteorolo-gy...

D. J. Stevenson

1981-11-06T23:59:59.000Z

99

Expanding Coherent Array Processing to Larger Apertures Using Empirical Matched Field Processing  

SciTech Connect

We have adapted matched field processing, a method developed in underwater acoustics to detect and locate targets, to classify transient seismic signals arising from mining explosions. Matched field processing, as we apply it, is an empirical technique, using observations of historic events to calibrate the amplitude and phase structure of wavefields incident upon an array aperture for particular repeating sources. The objective of this project is to determine how broadly applicable the method is and to understand the phenomena that control its performance. We obtained our original results in distinguishing events from ten mines in the Khibiny and Olenegorsk mining districts of the Kola Peninsula, for which we had exceptional ground truth information. In a cross-validation test, some 98.2% of 549 explosions were correctly classified by originating mine using just the Pn observations (2.5-12.5 Hz) on the ARCES array at ranges from 350-410 kilometers. These results were achieved despite the fact that the mines are as closely spaced as 3 kilometers. Such classification performance is significantly better than predicted by the Rayleigh limit. Scattering phenomena account for the increased resolution, as we make clear in an analysis of the information carrying capacity of Pn under two alternative propagation scenarios: free-space propagation and propagation with realistic (actually measured) spatial covariance structure. The increase in information capacity over a wide band is captured by the matched field calibrations and used to separate explosions from very closely-spaced sources. In part, the improvement occurs because the calibrations enable coherent processing at frequencies above those normally considered coherent. We are investigating whether similar results can be expected in different regions, with apertures of increasing scale and for diffuse seismicity. We verified similar performance with the closely-spaced Zapolyarni mines, though discovered that it may be necessary to divide event populations from a single mine into identifiable subpopulations. For this purpose, we perform cluster analysis using matched field statistics calculated on pairs of individual events as a distance metric. In our initial work, calibrations were derived from ensembles of events ranging in number to more than 100. We are considering the performance now of matched field calibrations derived with many fewer events (even, as mentioned, individual events). Since these are high-variance estimates, we are testing the use of cross-channel, multitaper, spectral estimation methods to reduce the variance of calibrations and detection statistics derived from single-event observations. To test the applicability of the technique in a different tectonic region, we have obtained four years of continuous data from 4 Kazakh arrays and are extracting large numbers of event segments. Our initial results using 132 mining explosions recorded by the Makanchi array are similar to those obtained in the European Arctic. Matched field processing clearly separates the explosions from three closely-spaced mines located approximately 400 kilometers from the array, again using waveforms in a band (6-10 Hz) normally considered incoherent for this array. Having reproduced ARCES-type performance with another small aperture array, we have two additional objectives for matched field processing. We will attempt to extend matched field processing to larger apertures: a 200 km aperture (the KNET) and, if data permit, to an aperture comprised of several Kazakh arrays. We also will investigate the potential of developing matched field processing to roughly locate and classify natural seismicity, which is more diffuse than the concentrated sources of mining explosions that we have investigated to date.

Ringdal, F; Harris, D B; Kvaerna, T; Gibbons, S J

2009-07-23T23:59:59.000Z

100

Stellar core collapse and supernova  

SciTech Connect

Massive stars that end their stable evolution as their iron cores collapse to a neutron star or black hole long been considered good candidates for producing Type II supernovae. For many years the outward propagation of the shock wave produced by the bounce of these iron cores has been studied as a possible mechanism for the explosion. For the most part, the results of these studies have not been particularly encouraging, except, perhaps, in the case of very low mass iron cores or very soft nuclear equations of state. The shock stalls, overwhelmed by photodisintegration and neutrino losses, and the star does not explode. More recently, slow late time heating of the envelope of the incipient neutron star has been found to be capable of rejuvenating the stalled shock and producing an explosion after all. The present paper discusses this late time heating and presents results from numerical calculations of the evolution, core collapse, and subsequent explosion of a number of recent stellar models. For the first time they all, except perhaps the most massive, explode with reasonable choices of input physics. 39 refs., 17 figs., 1 tab.

Wilson, J.R.; Mayle, R.; Woosley, S.E.; Weaver, T.

1985-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

Tracer transport in the Greenland Ice Sheet: constraints on ice cores and glacial history  

Science Journals Connector (OSTI)

The climate history and dynamics of the Greenland Ice Sheet are studied using a coupled model of the depositional provenance and transport of glacier ice, allowing simultaneous prediction of the detailed isotopic stratigraphy of ice cores at all the major Greenland sites. Adopting a novel method for reconstructing the age–depth relationship, we greatly improve the accuracy of semi-Lagrangian tracer tracking schemes and can readily incorporate an age-dependent ice rheology. The larger aim of our study is to impose new constraints on the glacial history of the Greenland Ice Sheet. Leading sources of uncertainty in the climate and dynamic history are encapsulated in a small number of parameters: the temperature and elevation isotopic sensitivities, the glacial–interglacial precipitation contrast and the effective viscosity of ice in the flow law. Comparing predicted and observed ice layering at ice core sites, we establish plausible ranges for the key model parameters, identify climate and dynamic histories that are mutually consistent and recover the past depositional elevation of ice cores to ease interpretation of their climatic records. With the coupled three-dimensional model of ice dynamics and provenance transport we propose a method to place all the ice core records on a common time scale and use discrepancies to adjust the reconstructed climate history. Analysis of simulated GRIP ice layering and borehole temperature profiles confirms that the GRIP record is sensitive to the dynamic as well as to the climatic history, but not enough to strongly limit speculation on the state of the Greenland Ice Sheet during the Eemian. In contrast, our study indicates that the Dye 3 and Camp Century ice cores are extremely sensitive to ice dynamics and greatly constrain Eemian ice sheet reconstructions. We suggest that the maximum Eemian sea-level contribution of the ice sheet was in the range of 3.5–4.5 m.

Nicolas Lhomme; Garry K.C. Clarke; Shawn J. Marshall

2005-01-01T23:59:59.000Z

102

Glacial-Interglacial Changes in Moisture Sources for Greenland: Influences on the Ice Core Record of Climate  

Science Journals Connector (OSTI)

...why the average amplitude of the 8180 shifts in the Camp Century ice core (north-west Greenland) is much larger than...the different ice cores. The issue of what sets the Camp Century core apart-including arguments for and against ice...

C. D. Charles; D. Rind; J. Jouzel; R. D. Koster; R. G. Fairbanks

1994-01-28T23:59:59.000Z

103

-The Core of CS -Curricula  

E-Print Network (OSTI)

- Advanced Courses #12;The Core of CS Curricula #12;CS Body of Knowledge Area > Unit > Topic Core vs elective#12;ACM vs U S I #12;- The Core of CS - Curricula - Introductory Courses - Intermediate Courses Introductory Intermediate Advanced Core Elective Units #12;Courses Introductory Intermediate Advanced Core

Hauswirth, Matthias

104

From detonation to diapers: Los Alamos computer codes at core...  

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

From detonation to diapers Los Alamos computer codes at core of advanced manufacturing tools The computer codes used for predictive fluid modeling are part of the Los Alamos...

105

Core shroud corner joints  

DOE Patents (OSTI)

A core shroud is provided, which includes a number of planar members, a number of unitary corners, and a number of subassemblies each comprising a combination of the planar members and the unitary corners. Each unitary corner comprises a unitary extrusion including a first planar portion and a second planar portion disposed perpendicularly with respect to the first planar portion. At least one of the subassemblies comprises a plurality of the unitary corners disposed side-by-side in an alternating opposing relationship. A plurality of the subassemblies can be combined to form a quarter perimeter segment of the core shroud. Four quarter perimeter segments join together to form the core shroud.

Gilmore, Charles B.; Forsyth, David R.

2013-09-10T23:59:59.000Z

106

Oxygen to the core  

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

1-01 1-01 For immediate release: 01/10/2013 | NR-13-01-01 Oxygen to the core Anne M Stark, LLNL, (925) 422-9799, stark8@llnl.gov Printer-friendly An artist's conception of Earth's inner and outer core. LIVERMORE, Calif. -- An international collaboration including researchers from Lawrence Livermore National Laboratory has discovered that the Earth's core formed under more oxidizing conditions than previously proposed. Through a series of laser-heated diamond anvil cell experiments at high pressure (350,000 to 700,000 atmospheres of pressure) and temperatures (5,120 to 7,460 degrees Fahrenheit), the team demonstrated that the depletion of siderophile (also known as "iron loving") elements can be produced by core formation under more oxidizing conditions than earlier

107

Core assembly storage structure  

DOE Patents (OSTI)

A structure for the storage of core assemblies from a liquid metal-cooled nuclear reactor. The structure comprises an enclosed housing having a substantially flat horizontal top plate, a bottom plate and substantially vertical wall members extending therebetween. A plurality of thimble members extend downwardly through the top plate. Each thimble member is closed at its bottom end and has an open end adjacent said top plate. Each thimble member has a length and diameter greater than that of the core assembly to be stored therein. The housing is provided with an inlet duct for the admission of cooling air and an exhaust duct for the discharge of air therefrom, such that when hot core assemblies are placed in the thimbles, the heat generated will by convection cause air to flow from the inlet duct around the thimbles and out the exhaust duct maintaining the core assemblies at a safe temperature without the necessity of auxiliary powered cooling equipment.

Jones, Jr., Charles E. (Northridge, CA); Brunings, Jay E. (Chatsworth, CA)

1988-01-01T23:59:59.000Z

108

New aspects in the analysis of loss-of-flow transients for homogeneous and heterogeneous LMFBR cores  

SciTech Connect

This paper presents the results of analyses of unprotected loss-of-flow (LOF) transients which have been performed to date using the new SAS4A code system. Accident histories for homogeneous and heterogeneous demo-sized cores (300 MWe) are compared and emphasis is placed on phenomena occurring after the initiation of fuel motion as described by LEVITATE. LEVITATE is the SAS4A model for the analysis of fuel and cladding dynamics under loss-of-flow (LOF) conditions and is believed to be the most-sophisticated computational tool currently available for fuel-motion analysis. The results of this analysis indicate that the initiation phase of an unprotected loss-of-flow accident has a considerably lower energetics potential in a heterogeneous core than in a homogeneous core. The difference is larger than previously indicated by SAS3D. Better phenomenological models implemented in SAS4A provide increased confidence in this aspect of safety evaluation of LMFBR cores.

Tentner, A.M.; Wider, H.U.

1982-01-01T23:59:59.000Z

109

Core Coupling in Nb-99  

E-Print Network (OSTI)

to be good. NUCLEAR REACTIONS, NUCLEAR STRUCTURE '"Mop, 'He), E =40.7 Mev, measured o(8) 99Nb levels deduced S. Calculated levels, 4, n', 8 NNb, particle- core-coupling model. The proton configurations of nuclei in the Zr-Mo region have been the subject... of much experimental interest. ' ' The only information available on ~Nb, however, was obtained by measurement of y decay following 99Zr P decay, ~ and is rather lim- ited. We have studied the levels of "Nb with the Mo(d, 'He) reaction at 40.7-Me...

Bindal, P. K.; Youngblood, David H.

1974-01-01T23:59:59.000Z

110

AO Core Competency Worksheet  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

AO Core Competency Worksheet AO Core Competency Worksheet 1 DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS Key Cyber Security Role: Authorizing Official (AO) Role Definition: The AO is the Senior DOE Management Federal official with the authority to formally assume responsibility and be held fully accountable for operating an information system at an acceptable level of risk. Competency Area: Incident Management Functional Requirement: Manage Competency Definition: Refers to the knowledge and understanding of the processes and procedures required to prevent, detect, investigate, contain, eradicate, and recover from incidents that impact the organizational mission as directed by the DOE Cyber Incident Response Capability (CIRC). Behavioral Outcome: Individuals fulfilling the role of AO will have a working knowledge of policies

111

Earth's Core Hottest Layer  

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

Earth's Core Hottest Layer Earth's Core Hottest Layer Name: Alfred Status: Grade: 6-8 Location: FL Country: USA Date: Spring 2011 Question: Why is the inner core the hottest layer? How is that possible? Replies: There are two factors causing the center of the Earth hotter than various layers of the Earth's. First, the more dense is the layer. The denser layer, the hotter it will be. In addition, the source of the heating is due to heat produced by nuclear decay. These substances tend to be more dense than lower dense substances. So the source of heat (temperature) is higher, the greater will be the temperature. Having said all that, the reasons are rather more complicated in the "real" Earth. If the inner layers were less dense they would rise (bubble) to the "surface" leaving the inner layers more dense and thus hotter layers.

112

2000 BTS Core Databook  

Buildings Energy Data Book (EERE)

0 BTS CORE DATABOOK 0 BTS CORE DATABOOK 2000 BTS CORE DATABOOK OFFICE OF ENERGY EFFICIENCY AND RENEWABLE ENERGY * U.S. DEPARTMENT OF ENERGY This version is dated: August 7, 2000 DISCLAIMER This document was designed for the internal use of the United States Department of Energy. This document was also designed to be occasionally updated and, therefore, this copy may not reflect the most current version. This document was prepared as account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that

113

Hopper Multi-Core FAQ  

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

Hopper Multi-Core FAQ Hopper Multi-Core FAQ Hopper Multi-Core FAQ Q. How is Hopper Different than Franklin? A. The new Hopper Phase-II system will have 24 cores per node. Franklin had only four. Q. What else is different? A. There is less memory per core. Hopper has 1.3 GB / core rather than 2.0 GB / core on Franklin. A code using MPI on Hopper may be more likely to exhaust available memory, causing an error. Additionally, Hopper's memory hierarchy is "deeper" and more non-uniform than Franklin's and this can have a big impact on performance in certain cases. Hopper's 24 cores per node are implemented on two sockets, each containing two six-core dies (see the image below). Each of the six-core dies has direct access to one-quarter of the node's total memory. Thus,

114

TMI-2 core examination  

SciTech Connect

The examination of the damaged core at the Three Mile Island Unit 2 (TMI-2) reactor is structured to address the following safety issues: fission product release, transport, and deposition; core coolability; containment integrity; and recriticality during severe accidents; as well as zircaloy cladding ballooning and oxidation during so-called design basis accidents. The numbers of TMI-2 components or samples to be examined, the priority of each examination, the safety issue addressed by each examination, the principal examination techniques to be employed, and the data to be obtained and the principal uses of the data are discussed in this paper.

Hobbins, R.R.; MacDonald, P.E.; Owen, D.E.

1983-01-01T23:59:59.000Z

115

SECA Core Technology Program  

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

January 27 - January 27 - 28, 2005 Workshop Peer Review Rating Results Summary Donald Collins SECA Core January 2005 Workshop Peer Review Summary - DWC,PM-30,3-10-05 2 of 21 Review Process Summary * Core Technology Project Presentations - Project Objectives & Results - Non-proprietary Information - Industry, National Lab & University Participation * Verbal & Written Constructive Comments - Written Comments on Peer Review Forms - Industry Verbal Feedback at Workshop * Core Participant Review & Reply to Comments - Reply to Comment Issues * DOE NETL Redirect Projects as Needed M a t e r i a l s C o n t r o l s & D i a g n o s t i c s P o w e r E le c t r o n ic s F u e l P r o c e s s i n g Manufacturing M o d e li n g & S im u la ti o n SECA Core January 2005 Workshop Peer Review Summary - DWC,PM-30,3-10-05 3 of 21 Peer Review Questions

116

SECA Core Technology Program  

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

May 12 - May 12 - 13, 2004 Workshop Peer Review Rating Results Summary Donald Collins SECA Core May 2004 Workshop Peer Review Summary - DWC,PM-30,5-21-04 2 of 16 Review Process Summary * Core Technology Project Presentations - Project Objectives & Results - Non-proprietary Information - Industry, National Lab & University Participation * Verbal & Written Constructive Comments - Written Comments on Peer Review Forms - Industry Verbal Feedback at Workshop * Core Participant Review & Reply to Comments - Reply to Comment Issues * DOE NETL Redirect Projects as Needed M a t e r i a l s C o n t r o l s & D i a g n o s t i c s P o w e r E le c t r o n ic s F u e l P r o c e s s i n g Manufacturing M o d e li n g & S im u la ti o n SECA Core May 2004 Workshop Peer Review Summary - DWC,PM-30,5-21-04 3 of 16 Peer Review Questions

117

Plan ?: core or cusp?  

Science Journals Connector (OSTI)

......research-article Article Plan beta: core or cusp? Thomas...Breddels (2013) for a detailed review of the more sophisticated numerical...is available for each star (standard technique). Large data sets...velocity space, we use the standard definition, for the velocity......

Thomas D. Richardson; Douglas Spolyar; Matthew D. Lehnert

2014-01-01T23:59:59.000Z

118

Core competence (knowledge) (skill)  

E-Print Network (OSTI)

Core competence 8 5~8 2 3 4 5 6 7 8 PPS003 Ver. 1.1 2011/03/07 #12; 2 (knowledge) (skill) (attitude) Set of skill, knowledge or attitude which should be learned or acquired by each, 2000) (knowledge) (skill) (attitude) Set of skill, knowledge or attitude which should be learned

Wu, Yih-Min

119

Dynamics of core accretion  

Science Journals Connector (OSTI)

......formation, the accretor is of course a rocky planetary core, on to which gas accretion...both cases, the distributions are nearly flat at large distances (i.e.-R H...the evolution of the simulation, using a safety factor of J- 4. Nevertheless, at time......

Andrew F. Nelson; Maximilian Ruffert

2013-01-01T23:59:59.000Z

120

Dynamics of core accretion  

Science Journals Connector (OSTI)

......the accretor is of course a rocky planetary core, on to which...the distributions are nearly flat at large distances (i.e...numerically induced collapse through violation of the Jeans criterion (Truelove...of the simulation, using a safety factor of J- 4. Nevertheless......

Andrew F. Nelson; Maximilian Ruffert

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

Core Holes | Open Energy Information  

Open Energy Info (EERE)

Core Holes Core Holes Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Core Holes Details Activities (8) Areas (7) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Drilling Techniques Exploration Sub Group: Exploration Drilling Parent Exploration Technique: Exploration Drilling Information Provided by Technique Lithology: Core holes are drilled to identify lithology and mineralization Stratigraphic/Structural: Retrieved samples can be used to identify fracture networks or faults Hydrological: Thermal: Thermal conductivity measurements can be done on retrieved samples. Dictionary.png Core Holes: A core hole is a well that is drilled using a hallow drill bit coated with synthetic diamonds for the purposes of extracting whole rock samples from

122

Core Measure Results  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Core Measure Core Measure Results FY 07 Results FY 08 Results FY 09 Results FY 10 Target FY 10 Customer Perspective: Customer Satisfaction: -Timeliness NM 81 NM NM NM -Quality NM 90 NM NM NM Effective Service Partnership: -Extent of Customer Satisfaction with the responsiveness, etc. NM 87 NM NM NM Internal Business Perspective: Acquisition Excellence: -Extent to which internal quality control systems are effective 86 87 84 87 88 Most Effective Use of Contracting Approaches to Maximize Efficiency and Cost Effectiveness: Use of Electronic Commerce: - % of delivery & purchase orders issued electronically as a % of total simplified actions 70 72 89 99 100 - % of new competitive transactions > $100K conducted through EC 70 72 91 100 95 Performance Based Service Contracts: - PBSCs awarded as a % of eligible new

123

Banded electromagnetic stator core  

DOE Patents (OSTI)

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups.

Fanning, Alan W. (San Jose, CA); Gonzales, Aaron A. (San Jose, CA); Patel, Mahadeo R. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

1996-01-01T23:59:59.000Z

124

Banded electromagnetic stator core  

DOE Patents (OSTI)

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups.

Fanning, Alan W. (San Jose, CA); Gonzales, Aaron A. (San Jose, CA); Patel, Mahadeo R. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

1994-01-01T23:59:59.000Z

125

Variable depth core sampler  

DOE Patents (OSTI)

A variable depth core sampler apparatus comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member.

Bourgeois, Peter M. (Hamburg, NY); Reger, Robert J. (Grand Island, NY)

1996-01-01T23:59:59.000Z

126

Electromagnetic pump stator core  

DOE Patents (OSTI)

A stator core for supporting an electrical coil includes a plurality of groups of circumferentially abutting flat laminations which collectively form a bore and perimeter. A plurality of wedges are interposed between the groups, with each wedge having an inner edge and a thicker outer edge. The wedge outer edges abut adjacent ones of the groups to provide a continuous path around the perimeter. 21 figures.

Fanning, A.W.; Olich, E.E.; Dahl, L.R.

1995-01-17T23:59:59.000Z

127

Banded electromagnetic stator core  

DOE Patents (OSTI)

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figs.

Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

1996-06-11T23:59:59.000Z

128

Banded electromagnetic stator core  

DOE Patents (OSTI)

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figures.

Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

1994-04-05T23:59:59.000Z

129

Variable depth core sampler  

DOE Patents (OSTI)

A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

Bourgeois, P.M.; Reger, R.J.

1996-02-20T23:59:59.000Z

130

Low local recurrence rate without postmastectomy radiation in node-negative breast cancer patients with tumors 5 cm and larger  

SciTech Connect

Purpose: To assess the need for adjuvant radiotherapy following mastectomy for patients with node-negative breast tumors 5 cm or larger. Methods and Materials: Between 1981 and 2002, a total of 70 patients with node-negative breast cancer and tumors 5 cm or larger were treated with mastectomy and adjuvant systemic therapies but without radiotherapy at three institutions. We retrospectively assessed rates and risk factors for locoregional failure (LRF), overall survival (OS), and disease-free survival (DFS) in these patients. Results: With a median follow-up of 85 months, the 5-year actuarial LRF rate was 7.6% (95% confidence interval, 3%-16%). LRF was primarily in the chest wall (4/5 local failures), and lymphatic-vascular invasion (LVI) was statistically significantly associated with LRF risk by the log-rank test (p = 0.017) and in Cox proportional hazards analysis (p 0.038). The 5-year OS and DFS rates were 83% and 86% respectively. LVI was also significantly associated with OS and DFS in both univariate and multivariate analysis. Conclusions: This series demonstrates a low LRF rate of 7.6% among breast cancer patients with node-negative tumors 5 cm and larger after mastectomy and adjuvant systemic therapy. Our data indicate that further adjuvant radiation therapy to increase local control may not be indicated by tumor size alone in the absence of positive lymph nodes. LVI was significantly associated with LRF in our series, indicating that patients with this risk factor require careful consideration with regard to further local therapy.

Floyd, Scott R. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Harvard Radiation Oncology Program, Harvard Medical School, Boston, MA (United States); Buchholz, Thomas A. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Haffty, Bruce G. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT (United States); Goldberg, Saveli [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Niemierko, Andrzej [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Raad, Rita Abi [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Oswald, Mary J. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Sullivan, Timothy [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Strom, Eric A. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Powell, Simon N. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Katz, Angela [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Taghian, Alphonse G. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)]. E-mail: ataghian@partners.org

2006-10-01T23:59:59.000Z

131

Core Analysis | Open Energy Information  

Open Energy Info (EERE)

Core Analysis Core Analysis Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Core Analysis Details Activities (41) Areas (28) Regions (2) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Core analysis is done to define lithology. Stratigraphic/Structural: Core analysis can locate faults or fracture networks. Oriented core can give additional important information on anisotropy. Hydrological: Thermal: Thermal conductivity can be measured from core samples. Cost Information Low-End Estimate (USD): 2,000.00200,000 centUSD 2 kUSD 0.002 MUSD 2.0e-6 TUSD / 30 foot core Median Estimate (USD): 10,000.001,000,000 centUSD

132

866 IEEE TRANSACTIONS ON MAGNETICS, VOL. 44, NO. 6, JUNE 2008 Dynamical Models for Eddy Current in Ferromagnetic Cores Introduced in  

E-Print Network (OSTI)

is composed of a magnet, a mas- sive circuit, a mobile vane linked to a spring, and a coil. Fig. 1 shows a current appears in the coil, the force created by the spring becomes inferior to the one created by the magnet and the coil; thus, the relay trips. A. Modeling of the Device Thanks to 3-D nonlinear FE model

Boyer, Edmond

133

Core polarization for the electric quadrupole moment of neutron-rich Aluminum isotopes  

E-Print Network (OSTI)

The core polarization effect for the electric quadrupole moment of the neutron-rich $^{31}$Al, $^{33}$Al and $^{35}$Al isotopes in the vicinity of the island of inversion are investigated by means of the microscopic particle-vibration coupling model in which the Skyrme Hartee-Fock-Bogoliubov and quasiparticle-random-phase approximation are used to calculate the single-quasiparticle wave functions and the excitation modes. It is found that the polarization charge for the proton $1d_{5/2}$ hole state in $^{33}$Al is quite sensitive to coupling to the neutrons in the $pf$-shell associated with the pairing correlations, and that the polarization charge in $^{35}$Al becomes larger due to the stronger collectivity of the low-lying quadrupole vibrational mode in the neighboring $^{36}$Si nucleus.

Kenichi Yoshida

2009-02-18T23:59:59.000Z

134

CFD Analysis of Core Bypass Phenomena  

SciTech Connect

The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the sector grid can be set as a symmetry boundary

Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

2010-03-01T23:59:59.000Z

135

CFD Analysis of Core Bypass Phenomena  

SciTech Connect

The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the one-twelfth grid can be set as a symmetry boundary

Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

2009-11-01T23:59:59.000Z

136

Improved core promoter prediction using ensembles of support vector machines  

E-Print Network (OSTI)

Improved core promoter prediction using ensembles of support vector machines Introduction to locate the core promoter region, or even more specific: where the transcription of a gene starts. Machine is very difficult to model in e.g. support vector machines (SVM) as there is so little positive

Gent, Universiteit

137

Core Competency Worksheets for Significant Cybersecurity Roles...  

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

Core Competency Worksheets for Significant Cybersecurity Roles Core Competency Worksheets for Significant Cybersecurity Roles The OCIO has developed core competency worksheets for...

138

Percolation Explains How Earth's Iron Core Formed | Stanford Synchrotron  

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

Percolation Explains How Earth's Iron Core Formed Percolation Explains How Earth's Iron Core Formed Wednesday, November 27, 2013 The formation of Earth's metallic core, which makes up a third of our planet's mass, represents the most significant differentiation event in Earth's history. Earth's present layered structure with a metallic core and an overlying silicate mantle would have required mechanisms to separate iron alloy from a silicate phase. Percolation of liquid iron alloy moving through a solid silicate matrix (much as water percolates through porous rock, or even coffee grinds) has been proposed as a possible model for core formation (Figure 1). Many previous experimental results have ruled out percolation as a major core formation mechanism for Earth at the relatively lower pressure conditions in the upper mantle, but until now experimental

139

RADIATION MAGNETOHYDRODYNAMIC SIMULATIONS OF PROTOSTELLAR COLLAPSE: PROTOSTELLAR CORE FORMATION  

SciTech Connect

We report the first three-dimensional radiation magnetohydrodynamic (RMHD) simulations of protostellar collapse with and without Ohmic dissipation. We take into account many physical processes required to study star formation processes, including a realistic equation of state. We follow the evolution from molecular cloud cores until protostellar cores are formed with sufficiently high resolutions without introducing a sink particle. The physical processes involved in the simulations and adopted numerical methods are described in detail. We can calculate only about one year after the formation of the protostellar cores with our direct three-dimensional RMHD simulations because of the extremely short timescale in the deep interior of the formed protostellar cores, but successfully describe the early phase of star formation processes. The thermal evolution and the structure of the first and second (protostellar) cores are consistent with previous one-dimensional simulations using full radiation transfer, but differ considerably from preceding multi-dimensional studies with the barotropic approximation. The protostellar cores evolve virtually spherically symmetric in the ideal MHD models because of efficient angular momentum transport by magnetic fields, but Ohmic dissipation enables the formation of the circumstellar disks in the vicinity of the protostellar cores as in previous MHD studies with the barotropic approximation. The formed disks are still small (less than 0.35 AU) because we simulate only the earliest evolution. We also confirm that two different types of outflows are naturally launched by magnetic fields from the first cores and protostellar cores in the resistive MHD models.

Tomida, Kengo [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)] [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Tomisaka, Kohji [Department of Astronomical Science, The Graduate University for Advanced Studies (SOKENDAI), Osawa, Mitaka, Tokyo 181-8588 (Japan)] [Department of Astronomical Science, The Graduate University for Advanced Studies (SOKENDAI), Osawa, Mitaka, Tokyo 181-8588 (Japan); Matsumoto, Tomoaki [Faculty of Humanity and Environment, Hosei University, Fujimi, Chiyoda-ku, Tokyo 102-8160 (Japan)] [Faculty of Humanity and Environment, Hosei University, Fujimi, Chiyoda-ku, Tokyo 102-8160 (Japan); Hori, Yasunori; Saigo, Kazuya [National Astronomical Observatory of Japan, Osawa, Mitaka, Tokyo 181-8588 (Japan)] [National Astronomical Observatory of Japan, Osawa, Mitaka, Tokyo 181-8588 (Japan); Okuzumi, Satoshi [Department of Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602 (Japan)] [Department of Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602 (Japan); Machida, Masahiro N., E-mail: tomida@astro.princeton.edu, E-mail: tomisaka@th.nao.ac.jp, E-mail: yasunori.hori@nao.ac.jp, E-mail: saigo.kazuya@nao.ac.jp, E-mail: matsu@hosei.ac.jp, E-mail: okuzumi@nagoya-u.jp, E-mail: machida.masahiro.018@m.kyushu-u.ac.jp [Department of Earth and Planetary Sciences, Faculty of Sciences, Kyushu University, Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)

2013-01-20T23:59:59.000Z

140

2001 BTS Core Databook  

Buildings Energy Data Book (EERE)

1 BTS CORE 1 BTS CORE DATABOOK OFFICE OF ENERGY EFFICIENCY AND RENEWABLE ENERGY U.S. DEPARTMENT OF ENERGY This version is dated: November 30, 2001 REVISED data tables on the web site that have been changed since November 30, 2001 include tables: 5.6.7 5.6.8 5.6.9 5.10.8 5.10.9 5.10.10 5.10.11 5.10.12 5.10.13 5.10.14 5.10.15 5.10.16 5.10.17 5.10.18 NEW data tables on the web site that have been added since July 13, 2001 include tables: 5.6.14 5.9.7 5.9.8 5.9.9 REVISED data tables on the web site that have been changed since July 13, 2001 include tables: 4.1.1 4.1.2 4.1.4 4.1.5 4.2.1 4.2.2 4.2.3 4.2.4 4.2.5 4.2.9 4.3.1 4.3.2 4.3.3 4.3.4 4.5.1 4.5.2 4.5.3 5.1.2 5.3.1 5.8.1 5.10.1 6.2.4 7.1.8 7.3.3 These tables are not included in this version of the 2001 BTS Core Databook. DISCLAIMER DISCLAIMER DISCLAIMER DISCLAIMER

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


141

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

142

Core-tube data logger  

SciTech Connect

Wireline core drilling, increasingly used for geothermal exploration, employs a core-tube to capture a rock core sample during drilling. Three types of core-tube data loggers (CTDL) have been built and tested to date by Sandia national Laboratories. They are: (1) temperature-only logger, (2) temperature/inclinometer logger and (3) heat-shielded temperature/inclinometer logger. All were tested during core drilling operations using standard wireline diamond core drilling equipment. While these tools are designed for core-tube deployment, the tool lends itself to be adapted to other drilling modes and equipment. Topics covered in this paper include: (1) description on how the CTDLs are implemented, (2) the components of the system, (3) the type of data one can expect from this type of tool, (4) lessons learned, (5) comparison to its counterpart and (6) future work.

Henfling, J.A.; Normann, R.A.; Knudsen, S.; Drumheller, D.

1997-01-01T23:59:59.000Z

143

The core pressure drop characteristics in a CANDU 6 reactor  

Science Journals Connector (OSTI)

The core pressure drop characteristics in a CANDU 6 have been examined to reveal the mechanism inducing the difference in the core pressure drop among four passages. The general characteristics for the inlet header temperature and core pressure drop are deduced from the measured data of CANDU 6 NPPs. The passages, which are connected to the purification system, are shown to have a larger core pressure drop and lower inlet header temperature compared with other passages in a loop. The temperature difference among four inlet headers has been analytically obtained by considering the effect of the purification system and verified by the measured data of CANDU 6 NPPs. The relationship between the inlet header temperature and core pressure drop has been secured from the magnetite transport mechanism in a CANDU 6. The analytical computations for a CANDU 6 NPP have revealed that the core pressure drop difference among four passages is largely dependent on the single phase friction factor rather than the mass flow rate in a passage. The calculated single phase friction factors are in accord with the magnetite deposition characteristics derived from the difference in the inlet header temperature.

Jun Ho Bae; Jong Yeob Jung

2013-01-01T23:59:59.000Z

144

SECA Core Technology Fossil Energy Fuel Cell Program  

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

June 3, 2003 June 3, 2003 National Energy Technology Laboratory Office of Fossil Energy SECA Core Technology IAPG, GPPD-DWC 4/30/03 SECA CORE TECHNOLOGY PROGRAM W. Nernst "Electrical Glow-Light" U.S. Patent 623,811 April 25, 1899 C C IAPG, GPPD-DWC 4/30/03 SECA SECA Program Structure Program Management Research Topics Needs Industry Integration Teams Technology Transfer Small Business University National Lab Industry Power Electronics Modeling & Simulation Materials Controls & Diagnostics Fuel Processing Fuel Processing Manufacturing Modeling & Simulation Power Electronics Controls & Diagnostics Manufacturing Materials Core Technology Program Fuel Cell Core Technology Project Management Industry Input IAPG, GPPD-DWC 4/30/03 Core Technology Program Powering All Ships Siemens Westinghouse

145

Dynamic core length in saturated core fault current limiters  

Science Journals Connector (OSTI)

A saturated core fault current limiter (SCFCL) is a non-linear core-reactor where the core is saturated by an external superconducting DC bias source to achieve a low core permeability at nominal AC currents. Fault current levels in the AC coils de-saturate the core and transform it to a higher permeability state, hence limiting the fault current. In this work we describe the transition between saturated and de-saturated states in three SCFCL configurations. The 'effective core length', Leff, of the SCFCL, defined as the length of the de-saturated AC core limb, is introduced for exploring this transition as a function of the current, I, in the AC coil. Practically, Leff allows one to see the SCFCL as an inductor with a variable core length, allowing calculations of the impedance of the SCFCL over the whole range of operating currents. The Leff(I) curve is further used to calculate the dynamics of the demagnetization factor in a SCFCL. We show that the strong change in the magnetic induction of a SCFCL at high current is the result of both increasing the effective core length and decreasing the demagnetization factor. The method and results presented here serve as an important tool for comparing between various SCFCL concepts not only by comparing their impedance values at the extreme fault and nominal current conditions but also by providing an insight into the full de-saturation process.

Y Nikulshin; Y Wolfus; A Friedman; Y Yeshurun

2013-01-01T23:59:59.000Z

146

AMIP Simulation with the CAM4 Spectral Element Dynamical Core  

SciTech Connect

We evaluate the climate produced by the Community Earth System Model, version 1, running with the new spectral-element atmospheric dynamical core option. The spectral-element method is congured to use a cubed-sphere grid, providing quasi-uniform resolution over the sphere, increased parallel scalability and removing the need for polar filters. It uses a fourth order accurate spatial discretization which locally conserves mass and moist total energy. Using the Atmosphere Model Intercomparison Project protocol, we compare the results from the spectral-element dy- namical core with those produced by the default nite-volume dynamical core and with observations.

Evans, Katherine J [ORNL; Lauritzen, Peter [National Center for Atmospheric Research (NCAR); Mishra, Saroj [National Center for Atmospheric Research (NCAR); Neale, Rich [National Center for Atmospheric Research (NCAR); Taylor, Mark [Sandia National Laboratories (SNL); Tribbia, Joe [National Center for Atmospheric Research (NCAR)

2013-01-01T23:59:59.000Z

147

Generating Unstructured Nuclear Reactor Core Meshes in Parallel  

Science Journals Connector (OSTI)

Abstract Recent advances in supercomputers and parallel solver techniques have enabled users to run large simulations problems using millions of processors. Techniques for multiphysics nuclear reactor core simulations are under active development in several countries. Most of these techniques require large unstructured meshes that can be hard to generate in a standalone desktop computers because of high memory requirements, limited processing power, and other complexities. We have previously reported on a hierarchical lattice-based approach for generating reactor core meshes. Here, we describe efforts to exploit coarse-grained parallelism during reactor assembly and reactor core mesh generation processes. We highlight several reactor core examples including a very high temperature reactor, a full-core model of the Korean MONJU reactor, a ¼ pressurized water reactor core, the fast reactor Experimental Breeder Reactor-II core with a XX09 assembly, and an advanced breeder test reactor core. The times required to generate large mesh models, along with speedups obtained from running these problems in parallel, are reported. A graphical user interface to the tools described here has also been developed.

Rajeev Jain; Timothy J. Tautges

2014-01-01T23:59:59.000Z

148

High level modeling and automated generation of heterogeneous SoC architectures with optimized custom reconfigurable cores and on-chip communication media  

Science Journals Connector (OSTI)

In this paper we propose a framework for modeling and automated generation of heterogeneous SoC architectures with emphasis on reconfigurable component integration and optimized communication media. In order to facilitate rapid development of SoC architectures, communication-centric platforms for data intensive applications, high level modeling of reconfigurable components for quick simulation and a tool for generation of complete SoC architectures is presented. Four different communication-centric platforms based on traditional bus, crossbar, hierarchical bus and novel hybrid communication media are proposed. These communication-centric platforms are proposed to cater for the different communication requirement of future SoC architectures. Multi-Standard telecommunication application is chosen as our target application domain and a case study of WiMAX is used as a real world example to demonstrate the effectiveness of our approach. A system consisting of an ARM processor, reconfigurable FFT and reconfigurable Viterbi decoder is considered with the option of system scalability for future upgrades. Behavior of system with different communication platforms is analyzed for its throughput and power characteristics with different reconfigurable scenarios to show the effectiveness of our approach.

Balal Ahmad; Ali Ahmadinia; Tughrul Arslan

2010-01-01T23:59:59.000Z

149

Application of the nuclear equation of state obtained by the variational method to core-collapse supernovae  

E-Print Network (OSTI)

The equation of state (EOS) for hot asymmetric nuclear matter which is constructed with the variational method starting from the Argonne v18 and Urbana IX nuclear forces is applied to spherically symmetric core-collapse supernovae (SNe). We first investigate the EOS of isentropic beta-stable SN matter, and find that the matter with the variational EOS is more neutron-rich than that with the Shen EOS. Using the variational EOS for uniform matter supplemented by the Shen EOS of non-uniform matter at low densities, we perform general-relativistic spherically symmetric simulations of core-collapse SNe with and without neutrino transfer, starting from a presupernova model of 15 solar mass. In the adiabatic simulation without neutrino transfer, the explosion is successful, and the explosion energy with the variational EOS is larger than that with the Shen EOS. In the case of the simulation with neutrino transfer, the shock wave stalls and then the explosion fails, as in other spherically symmetric simulations. The inner core with the variational EOS is more compact than that with the Shen EOS, due to the relative softness of the variational EOS. This implies that the variational EOS is more advantageous for SN explosions than the Shen EOS.

H. Togashi; M. Takano; K. Sumiyoshi; K. Nakazato

2014-03-04T23:59:59.000Z

150

A Data-Parallel Algorithmic Modelica Extension for Efficient Execution on Multi-Core Platforms  

E-Print Network (OSTI)

of purely equation-based Modelica models for simulation on NVIDIA Graphic Processing Units (GPUs). Several Parallel Simulation of Modelica Models on Multi-Core Computers The process of compiling and simulating-prone. To make the computational power of new multi-core architectures more easily available to Modelica modelers

Zhao, Yuxiao

151

Modeling particle deposition on HVAC heat exchangers  

SciTech Connect

Fouling of fin-and-tube heat exchangers by particle deposition leads to diminished effectiveness in supplying ventilation and air conditioning. This paper explores mechanisms that cause particle deposition on heat exchanger surfaces. We present a model that accounts for impaction, diffusion, gravitational settling, and turbulence. Simulation results suggest that some submicron particles deposit in the heat exchanger core, but do not cause significant performance impacts. Particles between 1 and 10 {micro}m deposit with probabilities ranging from 1-20% with fin edge impaction representing the dominant mechanism. Particles larger than 10 {micro}m deposit by impaction on refrigerant tubes, gravitational settling on fin corrugations, and mechanisms associated with turbulent airflow. The model results agree reasonably well with experimental data, but the deposition of larger particles at high velocities is underpredicted. Geometric factors, such as discontinuities in the fins, are hypothesized to be responsible for the discrepancy.

Siegel, J.A.; Nazaroff, W.W.

2002-01-01T23:59:59.000Z

152

Revised estimates of Greenland ice sheet thinning histories based on ice-core records  

Science Journals Connector (OSTI)

Ice core records were recently used to infer elevation changes of the Greenland ice sheet throughout the Holocene. The inferred elevation changes show a significantly greater elevation reduction than those output from numerical models, bringing into question the accuracy of the model-based reconstructions and, to some extent, the estimated elevation histories. A key component of the ice core analysis involved removing the influence of vertical surface motion on the ?18O signal measured from the Agassiz and Renland ice caps. We re-visit the original analysis with the intent to determine if the use of more accurate land uplift curves can account for some of the above noted discrepancy. To improve on the original analysis, we apply a geophysical model of glacial isostatic adjustment calibrated to sea-level records from the Queen Elizabeth Islands and Greenland to calculate the influence of land height changes on the ?18O signal from the two ice cores. This procedure is complicated by the fact that ?18O contained in Agassiz ice is influenced by land height changes distant from the ice cap and so selecting a single location at which to compute the land height signal is not possible. Uncertainty in this selection is further complicated by the possible influence of Innuitian ice during the early Holocene (12–8 ka BP). Our results indicate that a more accurate treatment of the uplift correction leads to elevation histories that are, in general, shifted down relative to the original curves at GRIP, NGRIP, DYE-3 and Camp Century. In addition, compared to the original analysis, the 1-? uncertainty is considerably larger at GRIP and NGRIP. These changes reduce the data-model discrepancy reported by Vinther et al. (2009) at GRIP, NGRIP, DYE-3 and Camp Century. A more accurate treatment of isostasy and surface loading also acts to improve the data-model fits such that the residuals at all four sites for the period 8 ka BP to present are significantly reduced compared to the original analysis. Prior to 8 ka BP, the possible influence of Innuitian ice on the inferred elevation histories prevents a meaningful comparison.

Benoit S. Lecavalier; Glenn A. Milne; Bo M. Vinther; David A. Fisher; Arthur S. Dyke; Matthew J.R. Simpson

2013-01-01T23:59:59.000Z

153

Elastic anisotropy of core samples from the Taiwan Chelungpu Fault Drilling Project (TCDP): direct 3-D measurements and weak anisotropy approximations  

Science Journals Connector (OSTI)

......samples from the same TCDP borehole. 2 Sampling and method...locations. The vertical drilling of TCDP Hole A in 2004...samples are cored from a large core retrieved at depth...measured velocities is quite large, from 1900 m s-1 at...although the location of the larger low velocity sector remains......

Laurent Louis; Christian David; Petr Špa?ek; Teng-fong Wong; Jérôme Fortin; Sheng Rong Song

2012-01-01T23:59:59.000Z

154

Alkali solution treatment on sandstone cores  

E-Print Network (OSTI)

was used for filtering the solution before the injection into the core. Hassler-t e Core Holder A stainless steel core holder was used to hold the core for treatment with the solutions. The core sample was positioned in the center of the core holder... and heat the water in the flask. Electric Heatin Ta e A silicone rubber embedded flexible heating tape was used to wrap the core holder to heat the core sample to the desired temperature. The maximum 0 continuous operating temperature of the tape...

Lee, Suk Jin

2012-06-07T23:59:59.000Z

155

An Estimate of the Order of Magnitude of the Explosion During a Core Meltdown-Compaction Accident for Heavy Liquid Metal Fast Reactors: A disquieting result updating the Bethe-Tait model  

E-Print Network (OSTI)

but lasting over a timescale of milliseconds. The forms of the energy release and of the resulting struc- tural damage differ significantly between a high explosive detonation and a propellant conflagration. Considering the yield of TNT Containment Law... gravitational compaction of the 100 MWth core, the ves- sel could withstand the 60 kg TNT-equivalent explosion from a 100 $/s reactivity insertion if a bare core is as- sumed; however, allowing for the presence of the unboiled heavy liquid metal coolant...

Arias, Francisco J.; Parks, Geoffrey T.

2014-12-09T23:59:59.000Z

156

License No. DPR-28 (Docket No. 50-271) Notification of the Installation of Larger Emergency Core Cooling System (ECCS) Suction Strainers In Accordance With NRC Bulletin 96-03  

E-Print Network (OSTI)

In accordance with the requested actions of Reference (a), Vermont Yankee is informing the staff of completion of our actions. During our 1998 Refueling Outage, Vermont Yankee installed large, passive, ECCS strainers under the provisions of 1 OCFR50.59. A description of how design inputs were chosen in our design of the strainers is provided in Attachment 1. Part of the design inputs for our strainers included the performance of plant-specific testing for behavior of coating debris. A proprietary description of this testing and the results is included in Attachment 2. Attachment 2 of the enclosed information is considered proprietary information by Duke Engineering and Services (DE&S). In accordance with 1OCFR2.790(b)(1), an affidavit attesting to the proprietary nature of the enclosed information is attached. A non-proprietary version of the testing and results is included in Attachment 3. In addition to the installation of new, high debris capacity strainers, the Torus inner surface, from the waterline and below, was re-coated with a qualified coating. Also, the drywell was cleaned and confirmed free of foreign material following an inspection in accordance with our drywell close-out procedure. The Torus was confirmed to be clear of foreign material following our replacement of strainers and re-coating project. The drywell vents and downcomers were likewise inspected and verified to be free of foreign materials.

Vermont Yankee

1999-01-01T23:59:59.000Z

157

Essential ingredients in core-collapse supernovae  

SciTech Connect

Carrying 10{sup 44} joules of kinetic energy and a rich mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up our solar system and ourselves. Signaling the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae combine physics over a wide range in spatial scales, from kilometer-sized hydrodynamic motions (eventually growing to gigameter scale) down to femtometer-scale nuclear reactions. We will discuss our emerging understanding of the convectively-unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have recently motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of the births of neutron stars and the supernovae that result. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.

Hix, W. Raphael [Physics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6354 (United States) [Physics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6354 (United States); Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Lentz, Eric J.; Chertkow, M. Austin; Harris, J. Austin [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States)] [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Endeve, Eirik [Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6008 (United States)] [Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6008 (United States); Baird, Mark [Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6003 (United States)] [Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6003 (United States); Messer, O. E. Bronson [Physics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6354 (United States) [Physics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6354 (United States); Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Center for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge TN 37831-6008 (United States); Mezzacappa, Anthony [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States) [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Joint Institute for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6173 (United States); Bruenn, Stephen [Department of Physics, Florida Atlantic University, 777 W Glades Road, Boca Raton, FL 33431-0991 (United States)] [Department of Physics, Florida Atlantic University, 777 W Glades Road, Boca Raton, FL 33431-0991 (United States); Blondin, John [Department of Physics, North Carolina State University, Raleigh, NC 27695-8202 (United States)] [Department of Physics, North Carolina State University, Raleigh, NC 27695-8202 (United States)

2014-04-15T23:59:59.000Z

158

Quadruple Adaptive Observer of the Core Temperature in Cylindrical  

E-Print Network (OSTI)

2/18 Background Thermal Management for Li ion batteries Safety: overheating, thermal runaway, Ford, SAE2003 Two states thermal model Online parameter Identification 4/18 Content Background Battery of battery core temperature 8/18 Content Background Battery Thermal Model and Online Identification

Stefanopoulou, Anna

159

What can the observed rotation of the Earth's inner core reveal about the state of the outer core?  

E-Print Network (OSTI)

present a model intermediate between these two extremes. In particular, I retain the simplicity of the model of Aurnou et al. by kinematically prescribing a thermal wind and poloidal magnetic ¢eld. By doing¡ect, the relationship between the inner core's rotation rate and the strength of the thermal wind is more complicated

Haase, Markus

160

PWR cores with silicon carbide cladding  

SciTech Connect

The feasibility of using silicon carbide rather than Zircaloy cladding, to reach higher power levels and higher discharge burnups in PWRs has been evaluated. A preliminary fuel design using fuel rods with the same dimensions as in the Westinghouse Robust Fuel Assembly but with fuel pellets having 10 vol% central void has been adopted to mitigate the higher fuel temperatures that occur due to the lower thermal conductivity of the silicon carbide and to the persistence of the open clad-pellet gap over most of the fuel life. With this modified fuel design, it is possible to achieve 18 month cycles that meet present-day operating constraints on peaking factor, boron concentration, reactivity coefficients and shutdown margin, while allowing batch average discharge burnups up to 80 MWD/kgU and peak rod burnups up to 100 MWD/kgU. Power uprates of 10% and possibly 20% also appear feasible. For non-uprated cores, the silicon carbide-clad fuel has a clear advantage that increases with increasing discharge burnup. Even for comparable discharge burnups, there is a savings in enriched uranium. Control rod configuration modifications may be required to meet the shutdown margin criterion for the 20% up-rate. Silicon carbide's ability to sustain higher burnups than Zircaloy also allows the design of a licensable two year cycle with only 96 fresh assemblies, avoiding the enriched uranium penalty incurred with use of larger batch sizes due to their excessive leakage. (authors)

Dobisesky, J. P.; Carpenter, D.; Pilat, E.; Kazimi, M. S. [Center for Advanced Nuclear Energy Systems, Dept. of Nuclear Science and Engineering, Massachusetts Inst. of Technology, 77 Massachusetts Avenue 24-215, Cambridge, MA 02139-4307 (United States)

2012-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

Core Analysis At International Geothermal Area, Philippines (Laney, 2005) |  

Open Energy Info (EERE)

Core Analysis At International Geothermal Area Core Analysis At International Geothermal Area Philippines (Laney, 2005) Exploration Activity Details Location International Geothermal Area Philippines Exploration Technique Core Analysis Activity Date Usefulness not indicated DOE-funding Unknown Notes Improving Exploration Models of Andesite-Hosted Geothermal Systems, Allis, Browne, Bruton, Christensen, Hulen, Lutz, Mindenhall, Nemcok, Norman, Powell and Stimac. The approach we are using is to characterize the petrology, geochemistry and fractures in core and cuttings samples and then integrate these data with measured downhole temperatures and pressures and with the compositions of the reservoir fluids. Our investigations represent cooperative efforts with the Karaha-Bodas Co. LLC (a subsidiary of Caithness Energy) at Karaha-Telaga Bodas, Indonesia and with Philippine

162

Do we need to know the temperature in prestellar cores?  

E-Print Network (OSTI)

Molecular line observations of starless (prestellar) cores combined with a chemical evolution modeling and radiative transfer calculations are a powerful tool to study the earliest stages of star formation. However, conclusions drawn from such a modeling may noticeably depend on the assumed thermal structure of the cores. The assumption of isothermality, which may work well in chemo-dynamical studies, becomes a critical factor in molecular line formation simulations. We argue that even small temperature variations, which are likely to exist in starless cores, can have a non-negligible effect on the interpretation of molecular line data and derived core properties. In particular, ``chemically pristine'' isothermal cores (low depletion) can have centrally peaked C$^{18}$O and C$^{34}$S radial intensity profiles, while having ring-like intensity distributions in models with a colder center and/or warmer envelope assuming the same underlying chemical structure. Therefore, derived molecular abundances based on oversimplified thermal models may lead to a mis-interpretation of the line data.

Ya. Pavlyuchenkov; Th. Henning; D. Wiebe

2007-09-28T23:59:59.000Z

163

Core Values | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Core Values Core Values Core Values People - People are our most important resource. We respect and use our experience and skills and appreciate our diversity. Business Excellence - We are fiscally responsible and actively pursue best business practices. Safety - We protect our human and material resources and promote safe work practices within the office and at our sites. Communication - We take full advantage of our virtual organization's strengths and share information freely across all levels of the organization. Leadership and Teamwork - We encourage leadership and teamwork at all levels of the organization. We value active participation and demonstrate respect for each other. Customer Service - We openly communicate with all our customers in a timely manner and actively seek opportunities to improve our services.

164

Definition: Core Analysis | Open Energy Information  

Open Energy Info (EERE)

Core Analysis Core Analysis Jump to: navigation, search Dictionary.png Core Analysis Core samples are obtained from drilling a well, typically using a synthetic diamond coated bit that has a hollow center so cylindrical rock samples ("core") can be extracted. Core samples successfully recovered are visually inspected to determine rock type, mineralization, and fracture networks, then certain laboratory analyses may ensue to acquire detailed rock properties. View on Wikipedia Wikipedia Definition A core sample is a cylindrical section of (usually) a naturally occurring substance. Most core samples are obtained by drilling with special drills into the substance, for example sediment or rock, with a hollow steel tube called a core drill. The hole made for the core sample is

165

Multi-core Performance Analysis  

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

core Performance Analysis core Performance Analysis HPC Computation 1 Performance Analysis * Compiler Feedback * HWPC Data * Load Balance 2 Compiler Feedback * Before optimizing code, it's critical to know what the compiler does to your code - Loop optimizations - Vectorization - Prefetching - ... * Equally important to what the compiler does is what it doesn't do, and why - Data dependencies - Misplaced branches - Unknown loop counts - ... 3 Enabling Compiler Feedback * Portland Group - Minfo=all - Mneginfo - Minfo=ccff (Common Compiler Feedback Format) * Cray - rm (Fortran) - hlist=m (C/C++) * Intel - vec-report1 * Pathscale - LNO:simd_verbose=ON:vintr_verbose=ON:prefetch_v erbose=ON * GNU - ftree-vectorizer-verbose=1

166

Neutronic analysis of pebble-bed cores with transuranics  

E-Print Network (OSTI)

(ORNL). This Department of Energy sponsored center is authorized to collect, maintain, analyze, and distribute computer software and data sets in the area of radiation transport and safety. The full-core VHTR pebble-bed model was developed... II.A SCALE 5.0 The 3D full-core pebble-bed VHTR model was initially built using SCALE version 5.0. The modular code system is developed and maintained by ORNL and is readily validated and accepted for use in thermal reactor analysis around...

Pritchard, Megan Leigh

2009-05-15T23:59:59.000Z

167

EFFECTS OF RESISTIVITY ON MAGNETIZED CORE-COLLAPSE SUPERNOVAE  

SciTech Connect

We studied the role of turbulent resistivity in the core-collapse of a strongly magnetized massive star, carrying out two-dimensional resistive-MHD simulations. Three cases with different initial strengths of magnetic field and rotation are investigated: (1) a strongly magnetized rotating core, (2) a moderately magnetized rotating core, and (3) a very strongly magnetized non-rotating core. In each case, one ideal-MHD model and two resistive-MHD models are computed. As a result of these computations, each model shows an eruption of matter assisted by magnetic acceleration (and also by centrifugal acceleration in the rotating cases). We found that resistivity attenuates the explosion in cases 1 and 2, while it enhances the explosion in case 3. We also found that in the rotating cases, the main mechanisms for the amplification of a magnetic field in the post-bounce phase are an outward advection of the magnetic field and a twisting of poloidal magnetic field lines by differential rotation, which are somewhat dampened down with the presence of resistivity. Although magnetorotational instability seems to occur in the rotating models, it plays only a minor role in magnetic field amplification. Another impact of resistivity is that on the aspect ratio. In the rotating cases, a large aspect ratio of the ejected matter, >2.5, attained in an ideal-MHD model is reduced to some extent in a resistive model. These results indicate that resistivity possibly plays an important role in the dynamics of strongly magnetized supernovae.

Sawai, H.; Suzuki, H. [Tokyo University of Science, Chiba 278-8510 (Japan)] [Tokyo University of Science, Chiba 278-8510 (Japan); Yamada, S. [Waseda University, Shinjuku, Tokyo 169-8555 (Japan)] [Waseda University, Shinjuku, Tokyo 169-8555 (Japan); Kotake, K. [National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan)] [National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan)

2013-02-10T23:59:59.000Z

168

Detector response in a CANDU low void reactivity core  

SciTech Connect

The response of the in-core flux detectors to the CANFLEX Low-Void-Reactivity Fuel (LVRF) [1] bundles for use in the CANDU reactor at Bruce nuclear generation station has been studied. The study was based on 2 detector types - platinum (Pt)-clad Inconel and pure Inconel detectors, and 2 fuel types - LVRF bundles and natural-uranium (NU) bundles. Both detectors show a decrease of thermal-neutron-flux to total-photon-flux ratio when NU fuel bundles are replaced by LVRF bundles in the reactor core (7% for Inconel and 9% for Pt-clad detectors). The ratio of the prompt component of the net electron current to the total net electron current (PFe) of the detectors however shows a different response. The use of LVRF bundles in place of NU fuel bundles in the reactor core did not change the PFe of the Pt-clad Inconel detector but increased the PFe of the pure Inconel detector by less than 2%. The study shows that the Inconel detector has a larger prompt-detector response than that of the platinum-clad detector; it reacts to the change of fluxes in the reactor core more readily. On the other hand, the Pt-clad detector is less sensitive to perturbations of the neutron-to-gamma ratio. Nevertheless the changes in an absolute sense are minimal; one does not anticipate a change of the flux-monitoring system if the NU fuel bundles are replaced with the CANFLEX LVRF bundles in the core of the Bruce nuclear generating station. (authors)

Tsang, K. T. [Atomic Energy of Canada Limited, 2251 Speakman Drive, Mississauga, Ont. L5K 1B2 (Canada)

2006-07-01T23:59:59.000Z

169

Large core fiber optic cleaver  

DOE Patents (OSTI)

The present invention relates to a device and method for cleaving optical fibers which yields cleaved optical fiber ends possessing high damage threshold surfaces. The device can be used to cleave optical fibers with core diameters greater than 400 {micro}m. 30 figs.

Halpin, J.M.

1996-03-26T23:59:59.000Z

170

Stability of Molten Core Materials  

SciTech Connect

The purpose of this report is to document a literature and data search for data and information pertaining to the stability of nuclear reactor molten core materials. This includes data and analysis from TMI-2 fuel and INL’s LOFT (Loss of Fluid Test) reactor project and other sources.

Layne Pincock; Wendell Hintze

2013-01-01T23:59:59.000Z

171

Wright State University CORE Scholar  

E-Print Network (OSTI)

Wright State University CORE Scholar Psychology Faculty Publications Psychology 10-1-2010 The Statistical Properties of the Survivor Interaction Contrast Joseph W. Houpt Wright State University - Main Campus, joseph.houpt@wright.edu James T. Townsend Follow this and additional works at: http://corescholar.libraries.wright

Townsend, James T.

172

Elastic properties of low density core (LDC) Ti-6Al-4V sandwich cores  

SciTech Connect

Lightweight, structurally efficient low density core (LDC) sandwich structures can be produced by entrapping argon gas within a finely dispersed distribution of pores in a microstructure and using a high temperature anneal to cause pore growth by gas expansion. This results in a porous microstructure with a relative density as low as {approximately}0.70. Laser ultrasonic methods have been used to measure the longitudinal and shear wave velocities and hence the elastic properties of LDC Ti-6Al-4V cores prior to, and after gas expansion treatments of up to 48 hr at 920 C. The data were compared with several analytical models for predicting the volume fraction of porosity dependent elastic properties of porous materials.

Queheillalt, D.T.; Wadley, H.N.G. [Univ. of Virginia, Charlottesville, VA (United States). IPM Lab.; Schwartz, D.S. [Boeing Co., St. Louis, MO (United States)

1998-12-31T23:59:59.000Z

173

40 K, high-resolution measurements with an energy resolution of several meVare required. The larger value of a (0.460.48) strongly  

E-Print Network (OSTI)

40 K, high-resolution measurements with an energy resolution of several meVare required. The larger role in SWNTs. A Methods Sample preparation In photoemission measurements, a relatively large sampling of the SWNTs were several micrometres. The purity of the SWNTsamples was estimated by electron-energy

Niu, Fenglin

174

Logging-while-coring method and apparatus  

DOE Patents (OSTI)

A method and apparatus for downhole coring while receiving logging-while-drilling tool data. The apparatus includes core collar and a retrievable core barrel. The retrievable core barrel receives core from a borehole which is sent to the surface for analysis via wireline and latching tool The core collar includes logging-while-drilling tools for the simultaneous measurement of formation properties during the core excavation process. Examples of logging-while-drilling tools include nuclear sensors, resistivity sensors, gamma ray sensors, and bit resistivity sensors. The disclosed method allows for precise core-log depth calibration and core orientation within a single borehole, and without at pipe trip, providing both time saving and unique scientific advantages.

Goldberg, David S. (New York, NY); Myers, Gregory J. (Cornwall, NY)

2007-11-13T23:59:59.000Z

175

Containment, Equivalence and Coreness from CSP to QCSP and beyond  

E-Print Network (OSTI)

The constraint satisfaction problem (CSP) and its quantified extensions, whether without (QCSP) or with disjunction (QCSP_or), correspond naturally to the model checking problem for three increasingly stronger fragments of positive first-order logic. Their complexity is often studied when parameterised by a fixed model, the so-called template. It is a natural question to ask when two templates are equivalent, or more generally when one "contain" another, in the sense that a satisfied instance of the first will be necessarily satisfied in the second. One can also ask for a smallest possible equivalent template: this is known as the core for CSP. We recall and extend previous results on containment, equivalence and "coreness" for QCSP_or before initiating a preliminary study of cores for QCSP which we characterise for certain structures and which turns out to be more elusive.

Madelaine, Florent

2012-01-01T23:59:59.000Z

176

Substation PSA Model  

Science Journals Connector (OSTI)

Chapter 6 describes how to create the substation model, the core of the PSA application... Chap. 4 . First, the modelling principles and then the details of the mode...

Liisa Haarla; Mikko Koskinen; Ritva Hirvonen…

2011-01-01T23:59:59.000Z

177

Analysis of fuel options for the breakeven core configuration of the Advanced Recycling Reactor  

SciTech Connect

A trade-off study is performed to determine the impacts of various fuel forms on the core design and core physics characteristics of the sodium-cooled Toshiba- Westinghouse Advanced Recycling Reactor (ARR). The fuel forms include oxide, nitride, and metallic forms of U and Th. The ARR core configuration is redesigned with driver and blanket regions in order to achieve breakeven fissile breeding performance with the various fuel types. State-of-the-art core physics tools are used for the analyses. In addition, a quasi-static reactivity balance approach is used for a preliminary comparison of the inherent safety performances of the various fuel options. Thorium-fueled cores exhibit lower breeding ratios and require larger blankets compared to the U-fueled cores, which is detrimental to core compactness and increases reprocessing and manufacturing requirements. The Th cores also exhibit higher reactivity swings through each cycle, which penalizes reactivity control and increases the number of control rods required. On the other hand, using Th leads to drastic reductions in void and coolant expansion coefficients of reactivity, with the potential for enhancing inherent core safety. Among the U-fueled ARR cores, metallic and nitride fuels result in higher breeding ratios due to their higher heavy metal densities. On the other hand, oxide fuels provide a softer spectrum, which increases the Doppler effect and reduces the positive sodium void worth. A lower fuel temperature is obtained with the metallic and nitride fuels due to their higher thermal conductivities and compatibility with sodium bonds. This is especially beneficial from an inherent safety point of view since it facilitates the reactor cool-down during loss of power removal transients. The advantages in terms of inherent safety of nitride and metallic fuels are maintained when using Th fuel. However, there is a lower relative increase in heavy metal density and in breeding ratio going from oxide to metallic or nitride Th fuels relative to the U counterpart fuels. (authors)

Stauff, N.E.; Klim, T.K.; Taiwo, T.A. [Argonne National Laboratory, Argonne, IL (United States); Fiorina, C. [Politecnico di Milano, Milan (Italy); Franceschini, F. [Westinghouse Electric Company LLC., Cranberry Township, Pennsylvania (United States)

2013-07-01T23:59:59.000Z

178

DIAGNOSING THE TIME DEPENDENCE OF ACTIVE REGION CORE HEATING FROM THE EMISSION MEASURE. II. NANOFLARE TRAINS  

SciTech Connect

The time dependence of heating in solar active regions can be studied by analyzing the slope of the emission measure distribution coolward of the peak. In a previous study we showed that low-frequency heating can account for 0% to 77% of active region core emission measures. We now turn our attention to heating by a finite succession of impulsive events for which the timescale between events on a single magnetic strand is shorter than the cooling timescale. We refer to this scenario as a 'nanoflare train' and explore a parameter space of heating and coronal loop properties with a hydrodynamic model. Our conclusions are (1) nanoflare trains are consistent with 86% to 100% of observed active region cores when uncertainties in the atomic data are properly accounted for; (2) steeper slopes are found for larger values of the ratio of the train duration {Delta} {sub H} to the post-train cooling and draining timescale {Delta} {sub C}, where {Delta} {sub H} depends on the number of heating events, the event duration and the time interval between successive events ({tau} {sub C}); (3) {tau} {sub C} may be diagnosed from the width of the hot component of the emission measure provided that the temperature bins are much smaller than 0.1 dex; (4) the slope of the emission measure alone is not sufficient to provide information about any timescale associated with heating-the length and density of the heated structure must be measured for {Delta} {sub H} to be uniquely extracted from the ratio {Delta} {sub H}/{Delta} {sub C}.

Reep, J. W.; Bradshaw, S. J. [Department of Physics and Astronomy, Rice University, Houston, TX 77005 (United States)] [Department of Physics and Astronomy, Rice University, Houston, TX 77005 (United States); Klimchuk, J. A., E-mail: jeffrey.reep@rice.edu, E-mail: stephen.bradshaw@rice.edu, E-mail: james.a.klimchuk@nasa.gov [NASA Goddard Space Flight Center, Solar Physics Lab., Code 671, 8800 Greenbelt Road, Greenbelt, MD 20771 (United States)

2013-02-20T23:59:59.000Z

179

Core analyses for selected samples from the Culebra Dolomite at the Waste Isolation Pilot Plant site  

SciTech Connect

Two groups of core samples from the Culebra Dolomite Member of the Rustler Formation at and near the Waste Isolation Pilot Plant were analyzed to provide estimates of hydrologic parameters for use in flow-and-transport modeling. Whole-core and core-plug samples were analyzed by helium porosimetry, resaturation and porosimetry, mercury-intrusion porosimetry, electrical-resistivity techniques, and gas-permeability methods. 33 refs., 25 figs., 10 tabs.

Kelley, V.A.; Saulnier, G.J. Jr. (INTERA, Inc., Austin, TX (USA))

1990-11-01T23:59:59.000Z

180

Modification of the Core Cooling System of TRIGA 2000 Reactor  

SciTech Connect

To accomplish safety requirements, a set of actions has to be performed following the recommendations of the IAEA safety series 35 applied to research reactor. Such actions are considered in modernization of the old system, improving the core cooling system and safety evaluations. Due to the complexity of the process and the difficulty in putting the apparatus in the reactor core, analytical and experimental study on the determination of flow and temperature distribution in the whole coolant channel are difficult to be done. In the present work, a numerical study of flow and temperature distribution in the coolant channel of TRIGA 2000 has been carried out using CFD package. For this study, simulations were carried out on 3-D tested model. The model consists of the reactor tank, thermal and thermalizing column, reflector, rotary specimen rack, chimney, fuel element, primary pipe, diffuser, beam tube and a part of the core are constructed by 1.50 million unstructured tetrahedral cell elements. The results show that for the initial condition (116 fuel elements in the core) and for the inlet temperature of 24 deg. C and the primary velocity of 5.6 m/s, there no boiling phenomena occur in the coolant channel. Due to this result, it is now possible to improve the core cooling system of TRIGA 2000 reactor. Meanwhile, forced flow from the diffuser system only affected the flow pattern in the outside of chimney and put on a small effect to the fluid flow's velocity in the inside of chimney.

Umar, Efrizon; Fiantini, Rosalina [National Nuclear Energy Agency of Indonesia, Jalan Tamansari 71, Bandung, 40132 (Indonesia)

2010-06-22T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

Warm Cores around Regions of Low-Mass Star Formation  

E-Print Network (OSTI)

Warm cores (or hot corinos) around low-mass protostellar objects show a rich chemistry with strong spatial variations. This chemistry is generally attributed to the sublimation of icy mantles on dust grains initiated by the warming effect of the stellar radiation. We have used a model of the chemistry in warm cores in which the sublimation process is based on extensive laboratory data; these data indicate that sublimation from mixed ices occurs in several well-defined temperature bands. We have determined the position of these bands for the slow warming by a solar-mass star. The resulting chemistry is dominated by the sublimation process and by subsequent gas-phase reactions; strong spatial and temporal variations in certain molecular species are found to occur, and our results are, in general, consistent with observational results for the well-studied source IRAS 16293-2422. The model used is similar to one that describes the chemistry of hot cores. We infer that the chemistry of both hot cores and warm core...

Awad, Zainab; Collings, Mark P; Williams, David A

2010-01-01T23:59:59.000Z

182

Processing of Activated Core Components  

SciTech Connect

Used activated components from the core of a NPP like control elements, water channels from a BWR, and others like in-core measurement devices need to be processed into waste forms suitable for interim storage, and for the final waste repository. Processing of the activated materials can be undertaken by underwater cutting and packaging or by cutting and high-pressure compaction in a hot cell. A hot cell is available in Germany as a joint investment between GNS and the Karlsruhe Research Center at the latter's site. Special transport equipment is available to transport the components ''as-is'' to the hot cell. Newly designed underwater processing equipment has been designed, constructed, and operated for the special application of NPP decommissioning. This equipment integrates an underwater cutting device with an 80 ton force underwater in-drum compactor.

Friske, A.; Gestermann, G.; Finkbeiner, R.

2003-02-26T23:59:59.000Z

183

TMI-2 core shipping preparations  

SciTech Connect

Shipping the damaged core from the Unit 2 reactor of Three Mile Island Nuclear Power Station near Harrisburg, PA, to the Idaho National Engineering Laboratory near Idaho Falls, ID, required development and implementation of a completely new spent fuel transportation system. This paper describes the equipment developed, the planning and activities used to implement the hardware systems into the facilities, and the planning involved in making the rail shipments. It also includes a summary of recommendations resulting from this experience.

Ball, L.J.; (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Barkanic, R.J. (Bechtel North American Power Corporation (United States)); Conaway, W.T. II (GPU Nuclear Corporation, Three Mile Island, Middletown, PA (United States)); Schmoker, D.S. (Nuclear Packaging, Inc., Federal Way, WA (United States))

1988-01-01T23:59:59.000Z

184

Laminated electromagnetic pump stator core  

DOE Patents (OSTI)

A stator core for an electromagnetic pump includes a plurality of circumferentially abutting tapered laminations extending radially outwardly from a centerline axis to collectively define a radially inner bore and a radially outer circumference. Each of the laminations includes radially inner and outer edges and has a thickness increasing from the inner edge toward the outer edge to provide a substantially continuous path adjacent the circumference. This pump is used in nuclear fission reactors. 19 figs.

Fanning, A.W.

1995-08-08T23:59:59.000Z

185

A CT scan aided core-flood study of the leak-off process in oil-based drilling fluids :.  

E-Print Network (OSTI)

??An experimental study on the leak-off of oil based drilling fluid sandstone cores is reported. First we revised the theoretical models for the rheology of… (more)

Van Overveldt, A.S.

2011-01-01T23:59:59.000Z

186

HyCore | Open Energy Information  

Open Energy Info (EERE)

HyCore Jump to: navigation, search Name: HyCore Place: Norway Sector: Hydro, Solar Product: JV between Umicore and Norsk Hydro to manufacture solar-grade silicon. References:...

187

Matrix Acidizing Parallel Core Flooding Apparatus  

E-Print Network (OSTI)

and provide this information to the field. To conduct various experiments, core flooding setups are created. The setup consists of a core holder, accumulator, overburden pump, injection pump, accumulator, pressure sensors, and a back pressure regulator...

Ghosh, Vivek

2013-07-23T23:59:59.000Z

188

NETL: SECA Core Technology Program Review  

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

SECA Core Technology Program Review SECA Core Technology Program Review February 19-20, 2003 Table of Contents Disclaimer Papers and Presentations Materials & Manufacturing Simulation and Modeling Fuel Processing Power Electronics, Sensors, Controls & Diagnostics Final Agenda [PDF-78KB] Peer Review Rating Results Summary [PDF-192KB] Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government or any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

189

The SimCore/Alpha Functional Simulator  

Science Journals Connector (OSTI)

We have developed a function-level processor simulator, SimCore/Alpha Functional Simulator Version 2.0 (SimCore Version 2.0), for processor architecture research and processor education. This paper describes the design and implementation of SimCore Version ...

Kenji Kise; Takahiro Katagiri; Hiroki Honda; Toshitsugu Yuba

2004-06-01T23:59:59.000Z

190

Core Competency Worksheets for Significant Cybersecurity Roles  

Energy.gov (U.S. Department of Energy (DOE))

OCIO has developed core competency worksheets for significant cyber roles to assist training personnel, curricula developers, supervisors, etc. with identifying core skills needed to perform their functional roles. Core competencies can be used to develop training objectives for site or organization-specific role-based training.

191

GCFR core thermal-hydralic design  

SciTech Connect

The approach for developing the thermal-hydraulic core assembly designs for the gas-cooled fast reactor (GCFR) is reviewed, and key considerations for improving the core performance at all power and flow conditions are discussed. It is shown how the thermal-hydraulic core assembly designs evolve from evaluations of plant size, material limitations, safety criteria, and structural performance considerations.

Schleuter, G.; Baxi, C.B.; Bennett, F.O.

1980-05-01T23:59:59.000Z

192

Russian techniques for more productive core drilling  

SciTech Connect

This is a short discussion of the trends and technology being used in Russia to increase the production of core drilling. The currently used rigs are given with the plans for improvement in drive methods and to reduce trip time in the recovery of cores. The recommendations by the Russians to improve the core recovery quality and quantity are also given.

Not Available

1984-09-01T23:59:59.000Z

193

Thermionic phenomena of the Earth's core and its effect on the geomagnetic field  

E-Print Network (OSTI)

In this model, we will show that the high-density quasi-plasma forms at the outer surface of the outer core and accounts for the geomagnetic field. The level of thermo-ionization at the outer surface of Earth's outer core is investigated...

Cao, Jiang

2012-06-07T23:59:59.000Z

194

Analysis of tru-fueled vhtr prismatic core performance domains  

E-Print Network (OSTI)

Regulatory Commission ORNL Oak Ridge National Laboratory P&T Partitioning and Transmutation PUREX Plutonium Uranium Reduction and Oxidation PWR Pressurized Water Reactor RGPu Reactor Grade Plutonium SCWCR Super-critical Water Cooled Reactor SFR Sodium.... The neutronics analysis using the 3D, whole-core VHTR model was performed using the ORNL SCALE (Standardized Computer Analysis for Licensing Evaluation) code system. The standard SCALE 5.1 TRITON sequence has been upgraded to allow fuel cycle modeling...

Lewis, Tom Goslee

2009-05-15T23:59:59.000Z

195

DOE CYBER SECURITY EBK: MINIMUM CORE COMPETENCY TRAINING REQUIREMENTS...  

Office of Environmental Management (EM)

DOE CYBER SECURITY EBK: MINIMUM CORE COMPETENCY TRAINING REQUIREMENTS DOE CYBER SECURITY EBK: MINIMUM CORE COMPETENCY TRAINING REQUIREMENTS DOE CYBER SECURITY EBK: CORE COMPETENCY...

196

DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CORE COMPETENCY TRAINING REQUIREMENTS: CA DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS: CA DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS. Key Cyber...

197

SoCore Energy | Open Energy Information  

Open Energy Info (EERE)

SoCore Energy SoCore Energy Jump to: navigation, search Name SoCore Energy Place Chicago, Illinois Zip 60601 Sector Solar Product Chicago-based solar installer and mounting solution company that also arranges for solar loans and PPAs. References SoCore Energy[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. SoCore Energy is a company located in Chicago, Illinois . References ↑ "SoCore Energy" Retrieved from "http://en.openei.org/w/index.php?title=SoCore_Energy&oldid=351218" Categories: Clean Energy Organizations Companies Organizations Stubs What links here Related changes Special pages Printable version Permanent link Browse properties About us Disclaimers Energy blogs

198

Analysis of BWR core nuclear thermal hydraulic oscillation with three dimensional transient program  

Science Journals Connector (OSTI)

A three-dimensional BWR core dynamics program STANDY has been developed. STANDY takes into account parallel channel effect and evaluates fuel thermal margin. Peach Bottom 2 and Vermont Yankee stability test data have been analyzed by STANDY. Calculated decay ratios and resonance frequencies agreed well with measured data. Limit cycle oscillation at Vermont Yankee test has been also simulated. Oscillation amplitude agreed well with experiment. A hypothetical core condition has been made up to examine unstable oscillations in BWR core. Analyses of the core revealed that oscillation at conditions close to instability initiation reaches small amplitude limit cycle, and change in fuel thermal margin is very small during the limit cycle. Although increase in core power or decrease in flow causes rapid increase in power oscillation amplitude, the ratio of thermal margin change to power amplitude stays almost constant. It has also been found that increase in hot channel power level does not necessarily cause larger thermal margin change because higher power may widen frequency difference between core average and hot channel.

O. Yokomizo; M. Sakurai; Y. Yoshimoto; K. Kitayama; T. Enomoto; N. Fukuda; K. Chuman

1987-01-01T23:59:59.000Z

199

Supercritical CO2 core flooding and imbibition in Berea sandstone — CT imaging and numerical simulation  

Science Journals Connector (OSTI)

This paper reports a numerical simulation study of a full CO2 core flooding and imbibition cycle on a Berea sandstone core (measured 14.45 cm long and 3.67 cm in diameter). During the test, supercritical CO2 (at 10 MPa and 40 °C) and CO2-saturated brine was injected into one end of the horizontal core and a X-ray CT scanner (with a resolution of 0.35 mm × 0.35 mm) was employed to monitor and record changes in the fluid saturations, which enabled 3D mapping of the saturation profiles throughout the core during the course of core flooding test. From the digital CT saturation data, mean saturation profiles along the core length were plotted with time. A 1D model of the core was constructed to simulate the core flooding test and attempt was made to history match core test results, particularly the evolution of the mean CO2 saturation profiles during CO2 injection. Curve-fitting of the centrifugal air-water capillary pressure data (drainage) for the Berea core showed that the core test data could be adequately described by the Van Genuchten equation. The matched set of parameters ( S l r , P 0 , m ) were 0.09, 20 KPa, 0.425 respectively. In the absence of the relative permeability for the Berea core, it was decided to use the parameters obtained from matching the air-water capillary pressure data as a first approximation for the CO2-brine system in the model.

Ji-Quan Shi; Ziqiu Xue; Sevket Durucan

2011-01-01T23:59:59.000Z

200

Tilt and shift mode stability in a spheromak with a flux core  

Science Journals Connector (OSTI)

The stability of spheromak equilibria with a flux core or reversal coil is studied by means of an ideal magnetohydrodynamic (MHD) code. Results depend critically upon whether the flux hole region (the current free area just inside the separatrix) is treated as a perfectly conducting plasma or as a vacuum. This indicates that the tilt and shift modes persist as resistive instabilities if they are stable in ideal MHD. Specifically for nonoptimally shaped equilibria the flux core must nearly touch the current channel if the flux hole is a vacuum whereas the core may be slightly outside the separatrix if the flux hole has conducting plasma. A larger margin exists for optimally shaped equilibria.

John M. Finn

1984-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

Grain Alignment by Radiation in Dark Clouds and Cores  

E-Print Network (OSTI)

We study alignment of grains by radiative torques. We found steep rise of radiative torque efficiency as grain size increases. This allows larger grains that are known to exist within molecular clouds to be aligned by the attenuated and reddened interstellar radiation field. In particular, we found that, even deep inside giant molecular clouds, e.g. at optical depths corresponding to less than Av of 10 large grains can still be aligned by radiative torque. This means that, contrary to earlier claims, far-infrared/submillimeter polarimetry provides a reliable tool to study magnetic fields of pre-stellar cores. Our results show that the grain size distribution is important for determining the relation between the degree of polarization and intensity.

J. Cho; A. Lazarian

2005-05-28T23:59:59.000Z

202

MODELING OBSERVATIONAL CONSTRAINTS FOR DARK MATTER HALOS  

SciTech Connect

Observations show that the underlying rotation curves at intermediate radii in spiral and low-surface-brightness galaxies are nearly universal. Further, in these same galaxies, the product of the central density and the core radius ({rho}{sub 0} r{sub 0}) is constant. An empirically motivated model for dark matter halos that incorporates these observational constraints is presented and shown to be in accord with the observations. A model fit to the observations of the galaxy cluster A611 shows that {rho}{sub 0} r{sub 0} for the dark matter halo in this more massive structure is larger by a factor of {approx}20 over that assumed for the galaxies. The model maintains the successful Navarro-Frenk-White form in the outer regions, although the well-defined differences in the inner regions suggest that modifications to the standard cold dark matter picture are required.

Hartwick, F. D. A. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8W 3P6 (Canada)

2012-12-01T23:59:59.000Z

203

COMET solutions to whole core CANDU-6 benchmark problems  

SciTech Connect

In this paper, the coarse mesh transport code COMET is used to solve CANDU-6 benchmark problems in two and three dimensional geometry. These problems are representative of a simplified quarter core reactor model. The COMET solutions, the core eigenvalue and the fuel pin fission density distribution, are compared to those from the Monte Carlo code MCNP using two-group cross sections. COMET decomposes the core volume into a set of non-overlapping sub-volumes (coarse meshes) and uses pre-computed heterogeneous response functions that are constructed using Legendre polynomials as boundary conditions to generate a user selected whole core solution (e.g., the core eigenvalue and fuel pin fission density distribution). These response functions are pre-computed by performing fixed source calculations with a modified version of MCNP in only the unique coarse meshes in the core. Reference solutions are calculated by MCNP5 with a two-group energy library generated with the HELIOS lattice code. In the 2-D problem, the angular current on the coarse mesh interfaces in COMET is expanded to 2. order in both spatial and angular variables. The COMET eigenvalue error is 0.09%. The corresponding average error in the fission density over all 3515 fuel pins is 0.5%. The maximum error observed is 2.0%. For the 3-D case, with 4. order expansion in space and azimuthal angle and 2. order expansion in the cosine of the polar angle, the eigenvalue differs from the reference solution by 0.05%. The average fission density error over the 42180 fuel pins is 0.7% with a maximum error of 3.3%. (authors)

Forget, B.; Rahnema, F. [Nuclear and Radiological Engineering / Medical Physics Programs, George W. Woodruff School, Georgia Inst. of Technology, Atlanta, GA 30332-0405 (United States)

2006-07-01T23:59:59.000Z

204

Test report -- Prototype core sampler  

SciTech Connect

The purpose of this test is to determine the adequacy of the prototype sampler, provided to Westinghouse Hanford Company (WHC) by DOE-RL. The sampler was fabricated for DOE-RL by the Concord Company by request of DOE-RL. This prototype sampler was introduced as a technology that can be easily deployed (similar to the current auger system) and will reliably collect representative samples. The sampler is similar to the Universal Sampler i.e., smooth core barrel and piston with an O-ring seal, but lacks a rotary valve near the throat of the sampler. This makes the sampler inappropriate for liquid sampling, but reduces the outside diameter of the sampler considerably, which should improve sample recovery. Recovery testing was performed with the supplied sampler in three different consistencies of Kaolin sludge simulants.

Linschooten, C.G.

1995-01-17T23:59:59.000Z

205

Nuclear core and fuel assemblies  

DOE Patents (OSTI)

A fast flux nuclear core of a plurality of rodded, open-lattice assemblies having a rod pattern rotated relative to a rod support structure pattern. Elongated fuel rods are oriented on a triangular array and laterally supported by grid structures positioned along the length of the assembly. Initial inter-assembly contact is through strongbacks at the corners of the support pattern and peripheral fuel rods between adjacent assemblies are nested so as to maintain a triangular pitch across a clearance gap between the other portions of adjacent assemblies. The rod pattern is rotated relative to the strongback support pattern by an angle .alpha. equal to sin .sup.-1 (p/2c), where p is the intra-assembly rod pitch and c is the center-to-center spacing among adjacent assemblies.

Downs, Robert E. (Monroeville, PA)

1981-01-01T23:59:59.000Z

206

Over Core Stress | Open Energy Information  

Open Energy Info (EERE)

Over Core Stress Over Core Stress Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Over Core Stress Details Activities (1) Areas (1) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Stratigraphic/Structural: Hydrological: Thermal: Dictionary.png Over Core Stress: No definition has been provided for this term. Add a Definition Related Techniques Rock Lab Analysis Core Analysis Cuttings Analysis Isotopic Analysis- Rock Over Core Stress Paleomagnetic Measurements Petrography Analysis Rock Density X-Ray Diffraction (XRD) X-Ray Fluorescence (XRF) References Page Area Activity Start Date Activity End Date Reference Material

207

Role of the core energy in the vortex Nernst effect  

Science Journals Connector (OSTI)

We present an analytical study of diamagnetism and transport in a film with superconducting phase fluctuations, formulated in terms of vortex dynamics within the Debye-Hückel approximation. We find that the diamagnetic and Nernst signals decay strongly with temperature in a manner that is dictated by the vortex core energy. Using the theory to interpret Nernst measurements of underdoped La2?xSrxCuO4 above the critical temperature regime, we obtain a considerably better fit to the data than a fit based on Gaussian order-parameter fluctuations. Our results indicate that the core energy in this system scales roughly with the critical temperature and is significantly smaller than expected from BCS theory. Furthermore, it is necessary to assume that the vortex mobility is much larger than the Bardeen-Stephen value in order to reconcile conductivity measurements with the same vortex picture. Therefore, either the Nernst signal is not due to fluctuating vortices, or vortices in underdoped La2?xSrxCuO4 have highly unconventional properties.

Gideon Wachtel and Dror Orgad

2014-11-11T23:59:59.000Z

208

Final Report for the "Fusion Application for Core-Edge Transport Simulations (FACETS)"  

SciTech Connect

The FACETS project over its lifetime developed the first self-consistent core-edge coupled capabilities, a new transport solver for modeling core transport in tokamak cores, developed a new code for modeling wall physics over long time scales, and significantly improved the capabilities and performance of legacy components, UEDGE, NUBEAM, GLF23, GYRO, and BOUT++. These improved capabilities leveraged the team’s expertise in applied mathematics (solvers and algorithms) and computer science (performance improvements and language interoperability). The project pioneered new methods for tackling the complexity of simulating the concomitant complexity of tokamak experiments.

Cary, John R; Kruger, Scott

2014-10-02T23:59:59.000Z

209

LINE PROFILES OF CORES WITHIN CLUSTERS. I. THE ANATOMY OF A FILAMENT  

SciTech Connect

Observations are revealing the ubiquity of filamentary structures in molecular clouds. As cores are often embedded in filaments, it is important to understand how line profiles from such systems differ from those of isolated cores. We perform radiative transfer calculations on a hydrodynamic simulation of a molecular cloud in order to model line emission from collapsing cores embedded in filaments. We model two optically thick lines, CS(2-1) and HCN(1-0), and one optically thin line, N{sub 2}H{sup +}(1-0), from three embedded cores. In the hydrodynamic simulation, gas self-gravity, turbulence, and bulk flows create filamentary regions within which cores form. Though the filaments have large dispersions, the N{sub 2}H{sup +}(1-0) lines indicate subsonic velocities within the cores. We find that the observed optically thick line profiles of CS(2-1) and HCN(1-0) vary drastically with viewing angle. In over 50% of viewing angles, there is no sign of a blue asymmetry, an idealized signature of infall motions in an isolated spherical collapsing core. Profiles that primarily trace the cores, with little contribution from the surrounding filament, are characterized by a systematically higher HCN(1-0) peak intensity. The N{sub 2}H{sup +}(1-0) lines do not follow this trend. We demonstrate that red asymmetric profiles are also feasible in the optically thick lines, due to emission from the filament or one-sided accretion flows onto the core. We conclude that embedded cores may frequently undergo collapse without showing a blue asymmetric profile, and that observational surveys including filamentary regions may underestimate the number of collapsing cores if based solely on profile shapes of optically thick lines.

Smith, Rowan J.; Shetty, Rahul; Klessen, Ralf S. [Zentrum fuer Astronomie der Universitaet Heidelberg, Institut fuer Theoretische Astrophysik, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany); Stutz, Amelia M., E-mail: rowanjsmith.astro@googlemail.com [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany)

2012-05-01T23:59:59.000Z

210

Large Pitch Hollow Core Honeycomb Fiber  

Science Journals Connector (OSTI)

A new kind of hollow core photonic crystal fiber (HC-PCF) for broadband guidance is introduced. Structural and optical properties of a fabricated example are detailed.

Beaudou, Benoît; Couny, François; Benabid, Fetah; Roberts, Peter John

211

Developing Renewable Energy Projects Larger Than 10 MWs at Federal Facilities (Book), Large-Scale Renewable Energy Guide, Federal Energy Management Program (FEMP)  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

LARGE-SCALE RENEWABLE ENERGY GUIDE LARGE-SCALE RENEWABLE ENERGY GUIDE Developing Renewable Energy Projects Larger Than 10 MWs at Federal Facilities A Practical Guide to Getting Large-Scale Renewable Energy Projects Financed with Private Capital Cover photos, clockwise from the top: Installing mirrored parabolic trough collectors - (January 19, 2012) Crews work around the clock installing mirrored parabolic trough collectors, built on site, that will cover 3 square miles at Abengoa's Solana Plant. Solana a 280 megawatt utility scale solar power plant (CSP) under construction in Gila Bend, Arizona, USA. When finished it will generate 280 MW 's of clean, sustainable power serving over 70,000 Arizona homes. Photo by Dennis Schroeder, NREL 20097 Dry Lake Wind Power Project in Arizona; Suzlon S88 wind turbines - The 63-MW Dry Lake Wind Power Project in Arizona is the first

212

Developing Renewable Energy Projects Larger Than 10 MWs at Federal Facilities (Book), Large-Scale Renewable Energy Guide, Federal Energy Management Program (FEMP)  

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

LARGE-SCALE RENEWABLE ENERGY GUIDE LARGE-SCALE RENEWABLE ENERGY GUIDE Developing Renewable Energy Projects Larger Than 10 MWs at Federal Facilities A Practical Guide to Getting Large-Scale Renewable Energy Projects Financed with Private Capital Cover photos, clockwise from the top: Installing mirrored parabolic trough collectors - (January 19, 2012) Crews work around the clock installing mirrored parabolic trough collectors, built on site, that will cover 3 square miles at Abengoa's Solana Plant. Solana a 280 megawatt utility scale solar power plant (CSP) under construction in Gila Bend, Arizona, USA. When finished it will generate 280 MW 's of clean, sustainable power serving over 70,000 Arizona homes. Photo by Dennis Schroeder, NREL 20097 Dry Lake Wind Power Project in Arizona; Suzlon S88 wind turbines - The 63-MW Dry Lake Wind Power Project in Arizona is the first

213

Ethylene oxide and Acetaldehyde in hot cores  

E-Print Network (OSTI)

[Abridged] Ethylene oxide and its isomer acetaldehyde are important complex organic molecules because of their potential role in the formation of amino acids. Despite the fact that acetaldehyde is ubiquitous in the interstellar medium, ethylene oxide has not yet been detected in cold sources. We aim to understand the chemistry of the formation and loss of ethylene oxide in hot and cold interstellar objects (i) by including in a revised gas-grain network some recent experimental results on grain surfaces and (ii) by comparison with the chemical behaviour of its isomer, acetaldehyde. We test the code for the case of a hot core. The model allows us to predict the gaseous and solid ethylene oxide abundances during a cooling-down phase prior to star formation and during the subsequent warm-up phase. We can therefore predict at what temperatures ethylene oxide forms on grain surfaces and at what temperature it starts to desorb into the gas phase. The model reproduces the observed gaseous abundances of ethylene oxid...

Occhiogrosso, A; Herbst, E; Viti, S; Ward, M D; Price, S D; Brown, W A

2014-01-01T23:59:59.000Z

214

Experimental Criticality Benchmarks for SNAP 10A/2 Reactor Cores  

SciTech Connect

This report describes computational benchmark models for nuclear criticality derived from descriptions of the Systems for Nuclear Auxiliary Power (SNAP) Critical Assembly (SCA)-4B experimental criticality program conducted by Atomics International during the early 1960's. The selected experimental configurations consist of fueled SNAP 10A/2-type reactor cores subject to varied conditions of water immersion and reflection under experimental control to measure neutron multiplication. SNAP 10A/2-type reactor cores are compact volumes fueled and moderated with the hydride of highly enriched uranium-zirconium alloy. Specifications for the materials and geometry needed to describe a given experimental configuration for a model using MCNP5 are provided. The material and geometry specifications are adequate to permit user development of input for alternative nuclear safety codes, such as KENO. A total of 73 distinct experimental configurations are described.

Krass, A.W.

2005-12-19T23:59:59.000Z

215

Molecule-based modeling of heavy oil  

Science Journals Connector (OSTI)

A molecular-level kinetics model has been developed for the pyrolysis of heavy residual oil. Resid structure was modeled in terms of three attribute groups: cores, inter-core linkages, and side chains. The con...

Scott R. Horton; Zhen Hou; Brian M. Moreno; Craig A. Bennett…

2013-07-01T23:59:59.000Z

216

BLACK HOLE FORMATION IN FAILING CORE-COLLAPSE SUPERNOVAE  

SciTech Connect

We present results of a systematic study of failing core-collapse supernovae and the formation of stellar-mass black holes (BHs). Using our open-source general-relativistic 1.5D code GR1D equipped with a three-species neutrino leakage/heating scheme and over 100 presupernova models, we study the effects of the choice of nuclear equation of state (EOS), zero-age main sequence (ZAMS) mass and metallicity, rotation, and mass-loss prescription on BH formation. We find that the outcome, for a given EOS, can be estimated, to first order, by a single parameter, the compactness of the stellar core at bounce. By comparing protoneutron star (PNS) structure at the onset of gravitational instability with solutions of the Tolman-Oppenheimer-Volkof equations, we find that thermal pressure support in the outer PNS core is responsible for raising the maximum PNS mass by up to 25% above the cold NS value. By artificially increasing neutrino heating, we find the critical neutrino heating efficiency required for exploding a given progenitor structure and connect these findings with ZAMS conditions, establishing, albeit approximately, for the first time based on actual collapse simulations, the mapping between ZAMS parameters and the outcome of core collapse. We also study the effect of progenitor rotation and find that the dimensionless spin of nascent BHs may be robustly limited below a* = Jc/GM{sup 2} = 1 by the appearance of nonaxisymmetric rotational instabilities.

O'Connor, Evan; Ott, Christian D., E-mail: evanoc@tapir.caltech.edu, E-mail: cott@tapir.caltech.edu [TAPIR, Mailcode 350-17, California Institute of Technology, Pasadena, CA 91125 (United States)

2011-04-01T23:59:59.000Z

217

Origin of the Core Francis Nimmo  

E-Print Network (OSTI)

Origin of the Core Francis Nimmo Dept. Earth Sciences, University of California, Santa Cruz F. Nimmo, Dept. Earth Sciences, University of California, Santa Cruz, CA 95064, USA (fnimmo@es.ucsc.edu), tel. 831-459-1783, fax. 831-459-3074 1 #12;Origin of the Core All major bodies of the inner solar

Nimmo, Francis

218

Idealized Test Cases for Dynamical Core Experiments  

E-Print Network (OSTI)

Idealized Test Cases for Dynamical Core Experiments Christiane Jablonowski (University of Michigan-13/2006 #12;Motivation · Test cases for 3D dynamical cores on the sphere ­ are hard to find in the literature groups ­ lack standardized & easy-to-use analysis techniques · Idea: Establish a collection of test cases

Jablonowski, Christiane

219

Experto Universitario Java Sesin 1: Spring core  

E-Print Network (OSTI)

Enterprise Spring © 2012-2013 Depto. Ciencia de la Computación e IA Spring core Puntos a tratar 2 #12;Experto Universitario Java Enterprise Spring © 2012-2013 Depto. Ciencia de la Computación e IA;Experto Universitario Java Enterprise Spring © 2012-2013 Depto. Ciencia de la Computación e IA Spring core

Escolano, Francisco

220

Module Handbook Core Univ. of Oldenburg  

E-Print Network (OSTI)

· Mechanical and Electrical Systems of the WEC Content: Energy conversion process in Wind Turbines · Wind/EUREC Course 2008/2009 #12;EUREC Core Courses at University of Oldenburg, 1st Semester Wind Energy Module Module Description: Wind Energy Field: Core Oldenburg Courses: Wind Energy Wind Energy

Habel, Annegret

Note: This page contains sample records for the topic "larger core models" 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

UNL Core for Applied Genomics and Ecology  

E-Print Network (OSTI)

UNL Core for Applied Genomics and Ecology Bioinformatics training Roche 454 GS-FLX Registration, Microbiomes, Variant Analysis, Whole Genomes, Transcriptomes Data Analysis and Statistics CAGE database and employer. University of Nebraska-Lincoln*Core for Applied Genomics and Ecology* 323 Filley Hall *Lincoln

Farritor, Shane

222

Analyses of Greek Research Reactor with mixed HEU-LEU Be reflected core  

SciTech Connect

The fuel-cycle analyses presented in this paper provide specific steps to be taken in the transition from a 36-element water-reflected HEU core to a 33-element LEU equilibrium core with a Be reflector on two faces. The first step will be to install the Be reflector and remove the highest burnup HEU fuel. The smaller Be-reflected core will be refueled with LEU fuel. All analyses were performed using a planar 5-group REBUS3 model benchmarked to VIM Monte Carlo. In addition to fuel cycle results, the control rod worth, reactivity response to increased fuel and water temperature and decreased water density were compared for the transition core and the reference HEU core.

Deen, J.R.; Snelgrove, J.L. [Argonne National Lab., IL (United States); Papastergiou, K. [National Center for Scientific Research, Athens (Greece)

1993-12-31T23:59:59.000Z

223

Core File Settings | Argonne Leadership Computing Facility  

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

Core File Settings Core File Settings The following environment variables control core file creation and contents. Specify regular (non-script) jobs using the qsub argument --env (Note: two dashes). Specify script jobs (--mode script) using the --envs (Note: two dashes) or --exp_env (Note: two dashes) options of runjob. For additional information about setting environment variables in your job, visit http://www.alcf.anl.gov/user-guides/running-jobs#environment-variables. Generation The following environment variables control conditions of core file generation and naming: BG_COREDUMPONEXIT=1 Creates a core file when the application exits. This is useful when the application performed an exit() operation and the cause and location of the exit() is not known. BG_COREDUMPONERROR=1

224

AN ANALYSIS OF THE DEUTERIUM FRACTIONATION OF STAR-FORMING CORES IN THE PERSEUS MOLECULAR CLOUD  

SciTech Connect

We have performed a pointed survey of N{sub 2}D{sup +} 2-1 and N{sub 2}D{sup +} 3-2 emission toward 64 N{sub 2}H{sup +}-bright starless and protostellar cores in the Perseus molecular cloud using the Arizona Radio Observatory Submillimeter Telescope and Kitt Peak 12 m telescope. We find a mean deuterium fractionation in N{sub 2}H{sup +}, R{sub D} = N(N{sub 2}D{sup +})/N(N{sub 2}H{sup +}), of 0.08, with a maximum R{sub D} = 0.2. In detected sources, we find no significant difference in the deuterium fractionation between starless and protostellar cores, nor between cores in clustered or isolated environments. We compare the deuterium fraction in N{sub 2}H{sup +} with parameters linked to advanced core evolution. We only find significant correlations between the deuterium fraction and increased H{sub 2} column density, as well as with increased central core density, for all cores. Toward protostellar sources, we additionally find a significant anticorrelation between R{sub D} and bolometric temperature. We show that the Perseus cores are characterized by low CO depletion values relative to previous studies of star-forming cores, similar to recent results in the Ophiuchus molecular cloud. We suggest that the low average CO depletion is the dominant mechanism that constrains the average deuterium fractionation in the Perseus cores to small values. While current equilibrium and dynamic chemical models are able to reproduce the range of deuterium fractionation values we find in Perseus, reproducing the scatter across the cores requires variation in parameters such as the ionization fraction or the ortho-to-para-H{sub 2} ratio across the cloud, or a range in core evolution timescales.

Friesen, R. K. [National Radio Astronomy Observatory, 520 Edgemont Rd., Charlottesville, VA 22903 (United States)] [National Radio Astronomy Observatory, 520 Edgemont Rd., Charlottesville, VA 22903 (United States); Kirk, H. M. [Origins Institute, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4M1 (Canada)] [Origins Institute, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4M1 (Canada); Shirley, Y. L., E-mail: friesen@di.utoronto.ca [Steward Observatory, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721 (United States)

2013-03-01T23:59:59.000Z

225

THE COLLAPSE OF TURBULENT CORES AND RECONNECTION DIFFUSION  

SciTech Connect

In order for a molecular cloud clump to form stars, some transport of magnetic flux is required from the denser internal regions to the outer regions; otherwise, this can prevent the gravitational collapse. Fast magnetic reconnection, which takes place in the presence of turbulence, can induce a process of reconnection diffusion that has been elaborated on in earlier theoretical works. We have named this process turbulent reconnection diffusion, or simply RD. This paper continues our numerical study of this process and its implications. In particular, we extend our studies of RD in cylindrical clouds and consider more realistic clouds with spherical gravitational potentials (from embedded stars); we also account for the effects of the gas self-gravity. We demonstrate that, within our setup reconnection, diffusion is efficient. We have also identified the conditions under which RD becomes strong enough to make an initially subcritical cloud clump supercritical and induce its collapse. Our results indicate that the formation of a supercritical core is regulated by a complex interplay between gravity, self-gravity, the magnetic field strength, and nearly transonic and trans-Alfvénic turbulence; therefore, it is very sensitive to the initial conditions of the system. In particular, self-gravity helps RD and, as a result, the magnetic field decoupling from the collapsing gas becomes more efficient compared with the case of an external gravitational field. Our simulations confirm that RD can transport magnetic flux from the core of collapsing clumps to the envelope, but only a few of them become nearly critical or supercritical sub-Alfvénic cores, which is consistent with the observations. Furthermore, we have found that the supercritical cores built up in our simulations develop a predominantly helical magnetic field geometry that is also consistent with recent observations. Finally, we have also evaluated the effective values of the turbulent RD coefficient in our simulations and found that they are much larger than the numerical diffusion coefficient, especially for initially trans-Alfvénic clouds, thus ensuring that the detected magnetic flux removal is due to the action of turbulent RD rather than numerical diffusivity.

Leão, M. R. M.; De Gouveia Dal Pino, E. M.; Santos-Lima, R. [Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, R. do Matão, 1226, São Paulo, SP 05508-090 (Brazil); Lazarian, A., E-mail: mleao@ime.unicamp.br, E-mail: dalpino@astro.iag.usp.br, E-mail: rlima@astro.iag.usp.br, E-mail: alazarian@facstaff.wisc.edu [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States)

2013-11-01T23:59:59.000Z

226

Natural thorium isotopes in marine sediment core off Labuan port  

SciTech Connect

Sediment core was collected from Labuan port and analyzed to determine the radioactivity of thorium (Th) isotopes. The objectives of this study are to determine the possible sources of Th isotopes at Labuan port and estimates the sedimentation rate based on {sup 228}Th/{sup 232}Th model. The results suggest the {sup 230}Th and {sup 232}Th might be originated from terrestrial sedimentary rock while {sup 228}Th originated by authigenic origin. High ratio value of {sup 230}Th/{sup 232}Th detected at the top surface sediment indicates the increasing of {sup 230}Th at the recent years which might be contributed from the anthropogenic sources. The sedimentation rate of core sediment from Labuan Port was successfully estimated by using {sup 228}Th/{sup 232}Th model. The result show high sedimentation rate with 4.67 cm/year indicates rapid deposition occurred at this study area due to the high physical activity at the Labuan port. By assume the constant sedimentation rate at this area; we estimated the age of 142 cm core sediment obtained from Labuan port is 32 years started from 1981 to 2012. This chronology will be used in forthcoming research to investigate the historical profile of anthropogenic activities affecting the Labuan port.

Hafidz, B. Y.; Asnor, A. S.; Terence, R. C.; Mohamed, C. A. R. [School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia 43600, Bangi, Selangor (Malaysia)

2014-02-12T23:59:59.000Z

227

OpenEI:Core content policies | Open Energy Information  

Open Energy Info (EERE)

content policies content policies Jump to: navigation, search OpenEI models its core content policies after those established by the Wikipedia.[1] Specifically, the OpenEI core content policies are: Neutral point of view - Content must have a neutral point of view, giving unbiased, equal, and proportional representation to all significant views. Verifiability - Any content coming from elsewhere must give attribution to it's source. Any content that is likely to be challenged must be attributed to a reliable and verifiable source. No original research - OpenEI is not a platform for original research. All content should come from and be attributed a verifiable source. These policies are not meant to be considered independently, but as a group. Anyone contributing to the platform should be familiar with each of

228

Core Analysis At International Geothermal Area, Indonesia (Laney, 2005) |  

Open Energy Info (EERE)

International Geothermal Area International Geothermal Area Indonesia (Laney, 2005) Exploration Activity Details Location International Geothermal Area Indonesia Exploration Technique Core Analysis Activity Date Usefulness not indicated DOE-funding Unknown Notes Improving Exploration Models of Andesite-Hosted Geothermal Systems, Allis, Browne, Bruton, Christensen, Hulen, Lutz, Mindenhall, Nemcok, Norman, Powell and Stimac. The approach we are using is to characterize the petrology, geochemistry and fractures in core and cuttings samples and then integrate these data with measured downhole temperatures and pressures and with the compositions of the reservoir fluids. Our investigations represent cooperative efforts with the Karaha-Bodas Co. LLC (a subsidiary of Caithness Energy) at Karaha-Telaga Bodas, Indonesia and with Philippine

229

SAS4A LMFBR whole core accident analysis code  

SciTech Connect

To ensure that public health and safety are protected even under accident conditions in an LMFBR, many accidents are analyzed for their potential consequences. Extremely unlikely accidents that might lead to melting of reactor fuel and release of radioactive fission products are referred to as hypothetical core disruptive accidents (HCDAs). The evaluation of such accidents involves the simultaneous evaluation of thermal, mechanical, hydraulic and neutronic processes and their interactions. The complexity of this analysis requires the use of large, integrated computer codes which address the response of the reactor core and several important systems. The SAS family of codes, developed at Argonne National Laboratory, provides such an analysis capability. The SAS4A code, the latest generation of this series of codes, has recently been completed and released for use to the LMFBR safety community. This paper will summarize the important new capabilitites of this analysis tool and illustrate an application of the integrated capability, while highlighting the importance of specific phenomenological models.

Weber, D.P.; Birgersson, G.; Bordner, G.L.; Briggs, L.L.; Cahalan, J.E.; Dunn, F.E.; Kalimullah; Miles, K.J.; Prohammer, F.G.; Tentner, A.M.

1985-01-01T23:59:59.000Z

230

Neutrino-driven supernova of a low-mass iron-core progenitor boosted by three-dimensional turbulent convection  

E-Print Network (OSTI)

We present the first successful simulation of a neutrino-driven supernova explosion in three dimensions (3D), using the Prometheus-Vertex code with an axis-free Yin-Yang grid and a sophisticated treatment of three-flavor, energy-dependent neutrino transport. The progenitor is a non-rotating, zero-metallicity 9.6 Msun star with an iron core. While in spherical symmetry outward shock acceleration sets in later than 300 ms after bounce, a successful explosion starts at ~130 ms post-bounce in two dimensions (2D). The 3D model explodes at about the same time but with faster shock expansion than in 2D and a more quickly increasing and roughly 10 percent higher explosion energy. The more favorable explosion conditions in 3D are explained by lower temperatures and thus reduced neutrino emission in the cooling layer below the gain radius. This moves the gain radius inward and leads to a bigger mass in the gain layer, whose larger recombination energy boosts the explosion energy in 3D. These differences are caused by l...

Melson, Tobias; Marek, Andreas

2015-01-01T23:59:59.000Z

231

510 Plant Disease / Vol. 97 No. 4 Etiology of Moldy Core, Core Browning, and Core Rot of Fuji Apple in China  

E-Print Network (OSTI)

510 Plant Disease / Vol. 97 No. 4 Etiology of Moldy Core, Core Browning, and Core Rot of Fuji Apple, and core rot of Fuji apple in China. Plant Dis. 97:510-516. `Fuji' apple fruit were collected in Shaanxi to species. Pathogenicity was determined by cutting apple fruit into halves and daubing spore suspensions

Biggs, Alan R.

232

Dynamic Inductance in Saturated Cores Fault Current Limiters  

Science Journals Connector (OSTI)

The saturated cores Fault Current Limiter (FCL) is one of the leading ... for providing a commercial robust solution to the fault current problem. Basically, the saturated cores FCL ... its saturated cores state ...

Y. Nikulshin; Y. Wolfus; A. Friedman…

2014-09-01T23:59:59.000Z

233

TCEQ-CoreDataForm | Open Energy Information  

Open Energy Info (EERE)

TCEQ-CoreDataForm Jump to: navigation, search OpenEI Reference LibraryAdd to library Form: TCEQ-CoreDataForm Abstract This is the core data form from the Texas Commission on...

234

Unearthing the Composition of Our Planet's Core  

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

Unearthing the Composition of Our Planet's Core Unearthing the Composition of Our Planet's Core The chemical composition of the Earth's core is surprisingly complicated, according to high-temperature, high-pressure experiments conducted by University of Chicago scientists using the William M. Keck High Pressure Laboratory at the GSECARS facility, APS sector 13. This research has produced experimental evidence suggesting that the Earth's inner core largely consists of two exotic forms of iron (rather than one as previously thought) that appear to be alloyed with silicon. Backscattered electron image of the quenched laser-heated diamond anvil cell sample from 31 GPa and 1976K. ( J.-F. Lin et al.) Above: Backscattered electron image of the quenched laser-heated diamond anvil cell sample from 31 GPa and 1976K. ( J.-F. Lin et al.)

235

GreenCore Capital | Open Energy Information  

Open Energy Info (EERE)

GreenCore Capital GreenCore Capital Jump to: navigation, search Logo: GreenCore Capital Name GreenCore Capital Address 10509 Vista Sorrento Parkway Place San Diego, California Zip 92121 Region Southern CA Area Product Invests in developing promising renewable energy companies Website http://www.greencorecapital.co Coordinates 32.898095°, -117.215736° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":32.898095,"lon":-117.215736,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

236

A New Greenland Deep Ice Core  

Science Journals Connector (OSTI)

...isotopic profile with that from camp Century and with a deep-sea foraminifera...deep-sea cores. The redated Camp Century record suggests a dramatic termination...CENTURIES OF CLIMATIC RECORD FROM CAMP CENTURY ON GREENLAND ICE SHEET, SCIENCE...

W. Dansgaard; H. B. Clausen; N. Gundestrup; C. U. Hammer; S. F. Johnsen; P. M. Kristinsdottir; N. Reeh

1982-12-24T23:59:59.000Z

237

ICE CORE RECORDS | Greenland Stable Isotopes  

Science Journals Connector (OSTI)

Abstract Greenland ice cores contain a wealth of information on past climatic conditions throughout the Northern Hemisphere. A historical perspective on the climatic interpretation of stable isotopes in water and ice is presented in the introduction, while the remainder of the article is devoted to the current interpretation of stable isotope data from Greenland ice cores. The progress in our understanding of stable isotope signals, on timescales from seasons to glacial cycles, is discussed and evaluated through numerous examples from Greenland ice cores. Stable isotope profiles from the Camp Century, Dye-3, GISP2, GRIP, NGRIP, and Renland deep ice cores are emphasized, as they all provide climatic information dating back into the Eemian period.

B.M. Vinther; S.J. Johnsen

2013-01-01T23:59:59.000Z

238

Crystallization of the crenarchaeal SRP core  

Science Journals Connector (OSTI)

The conserved ribonucleoprotein core of the signal recognition particle (SRP) has been crystallized. Both crystal forms are highly twinned and an explanation for the possible tetartohedral twinning is presented.

Rosendal, K.R.

2003-12-18T23:59:59.000Z

239

Xenon Oscillations in a VVÉR-1000 Core  

Science Journals Connector (OSTI)

Xenon oscillations – periodic redistribution of the power over ... the large size of this core. The xenon oscillations can be conventionally divided into axial, radial ... paper, methods are described for initiat...

V. A. Tereshonok; V. S. Stepanov; V. P. Povarov; O. V. Lebedev…

2002-10-01T23:59:59.000Z

240

Environmental impact of various kayak core materials  

E-Print Network (OSTI)

This thesis compares the environmental impact of fiberglass, Kevlar, carbon fiber, and cork. A kayak company is interested in using cork as a core material, and would like to claim that it is the most environmentally ...

Kirkland, David R. (David Roger)

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

PRELIMINARY TIME ESTIMATES FOR CORING OPERATIONS  

E-Print Network (OSTI)

EQUATIONS 17 FIGURE 1. DRILL STRING ROUND TRIP 19 FIGURE 2. STANDARD ROTARY CORING (RCB) WIRELINE TRIP 21) WIRELINE TRIP 25 FIGURE 5. ESTIMATED RIGGING, WIRELINE, AND SCANNING TIME FOR REENTRY. 27 #12;Preliminary

242

MagLab - Magnetic Core Memory Tutorial  

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

grid is made up of wires. The purpose of the horizontal and vertical X and Y Address Lines is to direct current to a specific core. The purpose of the diagonal Sense Lines is to...

243

Armor systems including coated core materials  

DOE Patents (OSTI)

An armor system and method involves providing a core material and a stream of atomized coating material that comprises a liquid fraction and a solid fraction. An initial layer is deposited on the core material by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is less than the liquid fraction of the stream of atomized coating material on a weight basis. An outer layer is then deposited on the initial layer by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is greater than the liquid fraction of the stream of atomized coating material on a weight basis.

2013-10-08T23:59:59.000Z

244

Armor systems including coated core materials  

DOE Patents (OSTI)

An armor system and method involves providing a core material and a stream of atomized coating material that comprises a liquid fraction and a solid fraction. An initial layer is deposited on the core material by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is less than the liquid fraction of the stream of atomized coating material on a weight basis. An outer layer is then deposited on the initial layer by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is greater than the liquid fraction of the stream of atomized coating material on a weight basis.

Chu, Henry S. (Idaho Falls, ID); Lillo, Thomas M. (Idaho Falls, ID); McHugh, Kevin M. (Idaho Falls, ID)

2012-07-31T23:59:59.000Z

245

Panelized wall system with foam core insulation  

DOE Patents (OSTI)

A wall system includes a plurality of wall members, the wall members having a first metal panel, a second metal panel, and an insulating core between the first panel and the second panel. At least one of the first panel and the second panel include ridge portions. The insulating core can be a foam, such as a polyurethane foam. The foam can include at least one opacifier to improve the k-factor of the foam.

Kosny, Jan (Oak Ridge, TN); Gaskin, Sally (Houston, TX)

2009-10-20T23:59:59.000Z

246

NETL: Control Technology: ElectroCore Separator  

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

ElectroCore Separator ElectroCore Separator LSR Technologies and its subcontractors designed and installed a 8,500 m3/hr (5,000 acfm) Advanced ElectroCore system and a dry sulfur scrubber to test it using an exhaust gas slipstream at Alabama Power Company's Gaston Steam Plant. Shakedown is scheduled for August 15, 2001. The exhaust gas will be from Unit #4 of a 270 MWe sub-critical, pulverized coal boiler burning a low-sulfur bituminous coal. The Advanced ElectroCore system will consist of a conventional upstream ESP, a dry SO2 scrubber, a particle precharger and an Advanced ElectroCore separator. Particle concentrations and size distributions will be measured at the ESP inlet, at the dry scrubber outlet and at the ElectroCore outlet. The concentration of 12 common HAPs will be measured at these locations as well. For purposes of project organization and monitoring, the work will be divided into nine (9) tasks described below.

247

Formed Core Sampler Hydraulic Conductivity Testing  

SciTech Connect

A full-scale formed core sampler was designed and functionally tested for use in the Saltstone Disposal Facility (SDF). Savannah River National Laboratory (SRNL) was requested to compare properties of the formed core samples and core drilled samples taken from adjacent areas in the full-scale sampler. While several physical properties were evaluated, the primary property of interest was hydraulic conductivity. Differences in hydraulic conductivity between the samples from the formed core sampler and those representing the bulk material were noted with respect to the initial handling and storage of the samples. Due to testing conditions, the site port samples were exposed to uncontrolled temperature and humidity conditions prior to testing whereas the formed core samples were kept in sealed containers with minimal exposure to an uncontrolled environment prior to testing. Based on the results of the testing, no significant differences in porosity or density were found between the formed core samples and those representing the bulk material in the test stand.

Miller, D. H.; Reigel, M. M.

2012-09-25T23:59:59.000Z

248

Solid oxide fuel cell having monolithic core  

DOE Patents (OSTI)

A solid oxide fuel cell is described for electrochemically combining fuel and oxidant for generating galvanic output, wherein the cell core has an array of electrolyte and interconnect walls that are substantially devoid of any composite inert materials for support. Instead, the core is monolithic, where each electrolyte wall consists of thin layers of cathode and anode materials sandwiching a thin layer of electrolyte material therebetween. The electrolyte walls are arranged and backfolded between adjacent interconnect walls operable to define a plurality of core passageways alternately arranged where the inside faces thereof have only the anode material or only the cathode material exposed. Means direct the fuel to the anode-exposed core passageways and means direct the oxidant to the anode-exposed core passageways and means direct the oxidant to the cathode-exposed core passageway; and means also direct the galvanic output to an exterior circuit. Each layer of the electrolyte and interconnect materials is of the order of 0.002 to 0.01 cm thick; and each layer of the cathode and anode materials is of the order of 0.002 to 0.05 cm thick.

Ackerman, J.P.; Young, J.E.

1983-10-12T23:59:59.000Z

249

Early Type Galaxy Core Phase Densities  

E-Print Network (OSTI)

Early type galaxies, ellipticals and S0's, have two distinct core density profiles, either a power law or nearly flat in projection. The two core types are distributed with substantial overlap in luminosity, radius, mass and velocity dispersion, however, the cores separate into two distinct distributions in their coarse grain phase density, Q_0 = rho/sigma^3,suggesting that dynamical processes played a dominant role in their origin. The transition phase density separating the two elliptical types is approximately 0.003 M_sun pc^-3 km^-3 s^3,. The Q_0*M_c^2 vs M_c diagram shows that globular clusters, nuclear star clusters and power-law cores fall on what is likely a "collisional" sequence of inspiralling globular clusters. on which the relative core mass excess varies as the bulk stellar mass to the -0.34+/-0.08 power, close to predictions, albeit with a correlation coefficient of -0.46. Both power-law and cored galaxies lie on a single sequence of approximately Q_0 ~r_c^-2.2, suggesting that transport proces...

Carlbeg, Raymond

2014-01-01T23:59:59.000Z

250

Core Overshoot: An Improved Treatment and Constraints from Seismic Data  

E-Print Network (OSTI)

We present a comprehensive set of stellar evolution models for Procyon A in an effort to guide future measurements of both traditional stellar parameters and seismic frequencies towards constraining the amount of core overshoot in Procyon A and possibly other stars. Current observational measurements of Procyon A when combined with traditional stellar modeling only place a large upper limit on overshoot of alphaOV < 1.1. By carrying out a detailed pulsation analysis, we further demonstrate, how p- and g-mode averaged spacings can be used to gain better estimates of the core size. For both p- and g-modes, the frequency spacings for models without overshoot are clearly separated from the models with overshoot. In addition, measurements of the l=0 averaged small p-mode spacings could be used to establish Procyon A's evolutionary stage. For a fixed implementation of overshoot and under favorable circumstances, the g-mode spacings can be used to determine the overshoot extent to an accuracy of +-0.05 Hp. However, we stress that considerable confusion is added due to the unknown treatment of the overshoot region. This ambiguity might be removed by analyzing many different stars. A simple non-local convection theory developed by Kuhfuss is implemented in our stellar evolution code and contrasted with the traditional approaches. We show that this theory supports a moderate increase of the amount of convective overshoot with stellar mass of Delta(alphaOV) = +0.10 between 1.5 Msun and 15 Msun. This theory places an upper limit on Procyon A's core overshoot extent of ~0.4 Hp which matches the limit imposed by Roxburgh's integral criterion.

Christian W. Straka; Pierre Demarque; D. B. Guenther

2005-05-01T23:59:59.000Z

251

Synthesis of Lutetium Phosphate/Apoferritin Core-Shell Nanoparticles...  

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

Core-Shell Nanoparticles for Potential Applications in Radioimmunoimaging and Synthesis of Lutetium PhosphateApoferritin Core-Shell Nanoparticles for Potential...

252

Core Analysis At International Geothermal Area, Indonesia (Boitnott...  

Open Energy Info (EERE)

Area Indonesia Exploration Technique Core Analysis Activity Date Usefulness not indicated DOE-funding Unknown References Greg N. Boitnott (2003) Core Analysis For The Development...

253

Core Analysis At Fenton Hill HDR Geothermal Area (Laughlin, Et...  

Open Energy Info (EERE)

Activity Details Location Fenton Hill HDR Geothermal Area Exploration Technique Core Analysis Activity Date - 1983 Usefulness useful DOE-funding Unknown Notes A few cores...

254

DOE CYBER SECURITY EBK: MINIMUM CORE COMPETENCY TRAINING REQUIREMENTS...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

DOE CYBER SECURITY EBK: MINIMUM CORE COMPETENCY TRAINING REQUIREMENTS DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS: CA Cybersecurity Program Manager (CSPM...

255

Smart” Diblock Copolymers as Templates for Magnetic-Core...  

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

Smart” Diblock Copolymers as Templates for Magnetic-Core Gold-Shell Nanoparticle Synthesis. Smart” Diblock Copolymers as Templates for Magnetic-Core Gold-Shell...

256

OpenStudio Core Development and Deployment Support - 2014 BTO...  

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

Core Development and Deployment Support - 2014 BTO Peer Review OpenStudio Core Development and Deployment Support - 2014 BTO Peer Review Presenter: Larry Brackney, National...

257

E-Print Network 3.0 - air-suspended solid-core fibers Sample...  

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

solid core subwavelength ber (a) and suspended porous core... December 2011 | 41 TERAHERTZ Suspended Core Subwavelength Plastic ... Source: Skorobogatiy, Maksim -...

258

* Events are part of User Group meeting ** Events are part of the larger GIS Day activities and are also part of the User Group meeting  

E-Print Network (OSTI)

with SketchUp and how it fits in our GIS world The University of New Hampshire's Energy and Campus Development will explore the various methods for producing 3D models using SketchUp as well as other interesting applications. Topics will include the difference between the free and Pro versions of SketchUp, AutoCAD drawing

New Hampshire, University of

259

THE COLD SHOULDER: EMISSION MEASURE DISTRIBUTIONS OF ACTIVE REGION CORES  

SciTech Connect

The coronal heating mechanism for active region core loops is difficult to determine because these loops are often not resolved and cannot be studied individually. Rather, we concentrate on the 'inter-moss' areas between loop footpoints. We use observations from the Hinode EUV Imaging Spectrometer and the X-Ray Telescope to calculate the emission measure distributions of eight inter-moss areas in five different active regions. The combined data sets provide both high- and low-temperature constraints and ensure complete coverage in the temperature range appropriate for active regions. For AR 11113, the emission can be modeled with heating events that occur on timescales less than the cooling time. The loops in the core regions appear to be close to equilibrium and are consistent with steady heating. The other regions studied, however, appear to be dominated by nanoflare heating. Our results are consistent with the idea that active region age is an important parameter in determining whether steady or nanoflare heating is primarily responsible for the core emission, that is, older regions are more likely to be dominated by steady heating, while younger regions show more evidence of nanoflares.

Schmelz, J. T.; Pathak, S., E-mail: jschmelz@memphis.edu [Physics Department, University of Memphis, Memphis, TN 38152 (United States)

2012-09-10T23:59:59.000Z

260

Search for methylamine in high mass hot cores  

E-Print Network (OSTI)

We aim to detect methylamine, CH$_{3}$NH$_{2}$, in a variety of hot cores and use it as a test for the importance of photon-induced chemistry in ice mantles and mobility of radicals. Specifically, CH$_3$NH$_2$ cannot be formed from atom addition to CO whereas other NH$_2$-containing molecules such as formamide, NH$_2$CHO, can. Submillimeter spectra of several massive hot core regions were taken with the James Clerk Maxwell Telescope. Abundances are determined with the rotational diagram method where possible. Methylamine is not detected, giving upper limit column densities between 1.9 $-$ 6.4 $\\times$ 10$^{16}$ cm$^{-2}$ for source sizes corresponding to the 100 K envelope radius. Combined with previously obtained JCMT data analyzed in the same way, abundance ratios of CH$_{3}$NH$_{2}$, NH$_{2}$CHO and CH$_{3}$CN with respect to each other and to CH$_{3}$OH are determined. These ratios are compared with Sagittarius B2 observations, where all species are detected, and to hot core models. The observed ratios su...

Ligterink, N F W; van Dishoeck, E F

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

The Spitzer c2d Survey of Nearby Dense Cores. X. Star Formation in L673 and CB188  

Science Journals Connector (OSTI)

L673 and CB188 are two low-mass clouds isolated from large star-forming regions that were observed as part of the Spitzer Legacy Project "From Molecular Clouds to Planet Forming disks" (c2d). We identified and characterized all the young stellar objects (YSOs) of these two regions and modeled their spectral energy distributions (SEDs) to examine whether their physical properties are consistent with values predicted from the theoretical models and with the YSO properties in the c2d survey of larger clouds. Overall, 30 YSO candidates were identified by the c2d photometric criteria, 27 in L673 and 3 in CB188. We confirm the YSO nature of 29 of them and remove a false Class III candidate in L673. We further present the discovery of two new YSO candidates, one Class 0 and another possible Class I candidate in L673, therefore bringing the total number of YSO candidates to 31. Multiple sites of star formation are present within L673, closely resembling other well-studied c2d clouds containing small groups such as B59 and L1251B, whereas CB188 seems to consist of only one isolated globule-like core. We measure a star formation efficiency (SFE) of 4.6%, which resembles the SFE of the larger c2d clouds. From the SED modeling of our YSO sample we obtain envelope masses for Class I and Flat spectrum sources of 0.01-1.0 M ?. The majority of Class II YSOs show disk accretion rates from 3.3 ? 10–10 to 3 ? 10–8 M ? yr–1 and disk masses that peak at 10–4 to 10–3 M ?. Finally, we examined the possibility of thermal fragmentation in L673 as the main star-forming process. We find that the mean density of the regions where significant YSO clustering occurs is of the order of ~105 cm–3 using 850 ?m observations and measure a Jeans Length that is greater than the near-neighbor YSO separations by approximately a factor of 3-4. We therefore suggest that other processes, such as turbulence and shock waves, may have had a significant effect on the cloud's filamentary structure and YSO clustering.

Anastasia E. Tsitali; Tyler L. Bourke; Dawn E. Peterson; Philip C. Myers; Michael M. Dunham; Neal J. Evans II; Tracy L. Huard

2010-01-01T23:59:59.000Z

262

THE SPITZER c2d SURVEY OF NEARBY DENSE CORES. X. STAR FORMATION IN L673 AND CB188  

SciTech Connect

L673 and CB188 are two low-mass clouds isolated from large star-forming regions that were observed as part of the Spitzer Legacy Project 'From Molecular Clouds to Planet Forming disks' (c2d). We identified and characterized all the young stellar objects (YSOs) of these two regions and modeled their spectral energy distributions (SEDs) to examine whether their physical properties are consistent with values predicted from the theoretical models and with the YSO properties in the c2d survey of larger clouds. Overall, 30 YSO candidates were identified by the c2d photometric criteria, 27 in L673 and 3 in CB188. We confirm the YSO nature of 29 of them and remove a false Class III candidate in L673. We further present the discovery of two new YSO candidates, one Class 0 and another possible Class I candidate in L673, therefore bringing the total number of YSO candidates to 31. Multiple sites of star formation are present within L673, closely resembling other well-studied c2d clouds containing small groups such as B59 and L1251B, whereas CB188 seems to consist of only one isolated globule-like core. We measure a star formation efficiency (SFE) of 4.6%, which resembles the SFE of the larger c2d clouds. From the SED modeling of our YSO sample we obtain envelope masses for Class I and Flat spectrum sources of 0.01-1.0 M{sub sun}. The majority of Class II YSOs show disk accretion rates from 3.3 x 10{sup -10} to 3 x 10{sup -8} M{sub sun} yr{sup -1} and disk masses that peak at 10{sup -4} to 10{sup -3} M{sub sun}. Finally, we examined the possibility of thermal fragmentation in L673 as the main star-forming process. We find that the mean density of the regions where significant YSO clustering occurs is of the order of {approx}10{sup 5} cm{sup -3} using 850 {mu}m observations and measure a Jeans Length that is greater than the near-neighbor YSO separations by approximately a factor of 3-4. We therefore suggest that other processes, such as turbulence and shock waves, may have had a significant effect on the cloud's filamentary structure and YSO clustering.

Tsitali, Anastasia E.; Bourke, Tyler L.; Peterson, Dawn E.; Myers, Philip C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Dunham, Michael M.; Evans, Neal J. [Department of Astronomy, The University of Texas at Austin, 1 University Station, C1400, Austin, TX 78712-0259 (United States); Huard, Tracy L., E-mail: atsitali@cfa.harvard.ed, E-mail: tbourke@cfa.harvard.ed, E-mail: dpeterson@cfa.harvard.ed, E-mail: pmyers@cfa.harvard.ed, E-mail: at306@soton.ac.u, E-mail: mdunham@astro.as.utexas.ed, E-mail: nje@astro.as.utexas.ed, E-mail: thuard@astro.umd.ed [University of Maryland, College Park, MD (United States)

2010-12-20T23:59:59.000Z

263

Overview on Hydrate Coring, Handling and Analysis  

SciTech Connect

Gas hydrates are crystalline, ice-like compounds of gas and water molecules that are formed under certain thermodynamic conditions. Hydrate deposits occur naturally within ocean sediments just below the sea floor at temperatures and pressures existing below about 500 meters water depth. Gas hydrate is also stable in conjunction with the permafrost in the Arctic. Most marine gas hydrate is formed of microbially generated gas. It binds huge amounts of methane into the sediments. Worldwide, gas hydrate is estimated to hold about 1016 kg of organic carbon in the form of methane (Kvenvolden et al., 1993). Gas hydrate is one of the fossil fuel resources that is yet untapped, but may play a major role in meeting the energy challenge of this century. In June 2002, Westport Technology Center was requested by the Department of Energy (DOE) to prepare a ''Best Practices Manual on Gas Hydrate Coring, Handling and Analysis'' under Award No. DE-FC26-02NT41327. The scope of the task was specifically targeted for coring sediments with hydrates in Alaska, the Gulf of Mexico (GOM) and from the present Ocean Drilling Program (ODP) drillship. The specific subjects under this scope were defined in 3 stages as follows: Stage 1: Collect information on coring sediments with hydrates, core handling, core preservation, sample transportation, analysis of the core, and long term preservation. Stage 2: Provide copies of the first draft to a list of experts and stakeholders designated by DOE. Stage 3: Produce a second draft of the manual with benefit of input from external review for delivery. The manual provides an overview of existing information available in the published literature and reports on coring, analysis, preservation and transport of gas hydrates for laboratory analysis as of June 2003. The manual was delivered as draft version 3 to the DOE Project Manager for distribution in July 2003. This Final Report is provided for records purposes.

Jon Burger; Deepak Gupta; Patrick Jacobs; John Shillinglaw

2003-06-30T23:59:59.000Z

264

Chains of dense cores in the Taurus L1495/B213 complex  

E-Print Network (OSTI)

(Abridged) We study the kinematics of the dense gas in the Taurus L1495/B213 filamentary region to investigate the mechanism of core formation. We use observations of N2H+(1-0) and C18O(2-1) carried out with the IRAM 30m telescope. We find that the dense cores in L1495/B213 are significantly clustered in linear chain-like groups about 0.5pc long. The internal motions in these chains are mostly subsonic and the velocity is continuous, indicating that turbulence dissipation in the cloud has occurred at the scale of the chains and not at the smaller scale of the individual cores. The chains also present an approximately constant abundance of N2H+ and radial intensity profiles that can be modeled with a density law that follows a softened power law. A simple analysis of the spacing between the cores using an isothermal cylinder model indicates that the cores have likely formed by gravitational fragmentation of velocity-coherent filaments. Combining our analysis of the cores with our previous study of the large-sc...

Tafalla, M

2014-01-01T23:59:59.000Z

265

Is inner core seismic anisotropy a marker of plastic flow of cubic iron?  

E-Print Network (OSTI)

This paper investigates whether observations of seismic anisotropy are compatible with a cubic structure of the inner core Fe alloy. We assume that anisotropy is the result of plastic deformation within a large scale flow induced by preferred growth at the inner core equator. Based on elastic moduli from the literature, bcc- or fcc-Fe produce seismic anisotropy well below seismic observations ($\\textless{}0.4\\%$). A Monte-Carlo approach allows us to generalize this result to any form of elastic anisotropy in a cubic system. Within our model, inner core global anisotropy is not compatible with a cubic structure of Fe alloy. Hence, if the inner core material is indeed cubic, large scale coherent anisotropic structures, incompatible with plastic deformation induced by large scale flow, must be present.

Lincot, A; Cardin, Philippe

2015-01-01T23:59:59.000Z

266

Thermal hydraulic aspects in the analysis of LMFBR disrupted-core situations  

SciTech Connect

This paper presents the thermal-hydraulic aspects of current interest in the modeling of LMFBR hypothetical core-disruptive accidents, with special emphasis on the Loss of Flow situations. The models presented have been incorporated in LEVITATE, a code for the analysis of fuel and cladding dynamics under LOF conditions, which has recently become part of the SAS4A code system. The influence of different thermal-hydraulic models on fuel motion is illustrated by a comparison between the results calculated by LEVITATE, the data from the L7-TREAT experiment and the results calculated by SLUMPY. The results calculated by LEVITATE are in fair agreement with the experimentally observed early fuel dispersal. The marginally acceptable energetic events obtained in the analysis of high void-worth LMFBR cores during Loss-of-Flow transients coupled with uncertainties about some of the thermal-hydraulic parameters motivate, among other factors, the need for the design low void-worth LMFBR cores.

Tentner, A.M.; Wider, H.U.

1981-01-01T23:59:59.000Z

267

Three-dimensional Continuum Radiative Transfer Images of a Molecular Cloud Core Evolution  

E-Print Network (OSTI)

We analyze a three-dimensional smoothed particle hydrodynamics simulation of an evolving and later collapsing pre-stellar core. Using a three-dimensional continuum radiative transfer program, we generate images at 7 micron, 15 micron, 175 micron, and 1.3 mm for different evolutionary times and viewing angles. We discuss the observability of the properties of pre-stellar cores for the different wavelengths. For examples of non-symmetric fragments, it is shown that, misleadingly, the density profiles derived from a one-dimensional analysis of the corresponding images are consistent with one-dimensional core evolution models. We conclude that one-dimensional modeling based on column density interpretation of images does not produce reliable structural information and that multidimensional modeling is required.

J. Steinacker; B. Lang; A. Burkert; A. Bacmann; Th. Henning

2004-10-12T23:59:59.000Z

268

CA Core Competency Worksheet August 2010  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CA Core Competency Worksheet August 2010 CA Core Competency Worksheet August 2010 1 DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS Key Cyber Security Role: Certification Agent (CA) (Also referred to as Security Control Assessor) Role Definition: The CA is the individual responsible for assessing the management, operational, assurance, and technical security controls implemented on an information system via security testing and evaluation (ST&E) methods. This individual must be independent of system development, operation, and deficiency mitigation. Competency Area: Data Security Functional Requirement: Design Competency Definition: Refers to the application of the principles, policies, and procedures necessary to ensure the confidentiality, integrity, availability, and privacy of data in all forms of media (i.e., electronic

269

Analytical Chemistry Core Capability Assessment - Preliminary Report  

SciTech Connect

The concept of 'core capability' can be nebulous one. Even at a fairly specific level, where core capability equals maintaining essential services, it is highly dependent upon the perspective of the requestor. Samples are submitted to analytical services because the requesters do not have the capability to conduct adequate analyses themselves. Some requests are for general chemical information in support of R and D, process control, or process improvement. Many analyses, however, are part of a product certification package and must comply with higher-level customer quality assurance requirements. So which services are essential to that customer - just those for product certification? Does the customer also (indirectly) need services that support process control and improvement? And what is the timeframe? Capability is often expressed in terms of the currently utilized procedures, and most programmatic customers can only plan a few years out, at best. But should core capability consider the long term where new technologies, aging facilities, and personnel replacements must be considered? These questions, and a multitude of others, explain why attempts to gain long-term consensus on the definition of core capability have consistently failed. This preliminary report will not try to define core capability for any specific program or set of programs. Instead, it will try to address the underlying concerns that drive the desire to determine core capability. Essentially, programmatic customers want to be able to call upon analytical chemistry services to provide all the assays they need, and they don't want to pay for analytical chemistry services they don't currently use (or use infrequently). This report will focus on explaining how the current analytical capabilities and methods evolved to serve a variety of needs with a focus on why some analytes have multiple analytical techniques, and what determines the infrastructure for these analyses. This information will be useful in defining a roadmap for what future capability needs to look like.

Barr, Mary E. [Los Alamos National Laboratory; Farish, Thomas J. [Los Alamos National Laboratory

2012-05-16T23:59:59.000Z

270

Reactor Core Assembly - HFIR Technical Parameters | ORNL Neutron Sciences  

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

Home › Facilities › HFIR › Reactor Core Assembly Home › Facilities › HFIR › Reactor Core Assembly Reactor Core Assembly The reactor core assembly is contained in an 8-ft (2.44-m)-diameter pressure vessel located in a pool of water. The top of the pressure vessel is 17 ft (5.18 m) below the pool surface, and the reactor horizontal mid-plane is 27.5 ft (8.38 m) below the pool surface. The control plate drive mechanisms are located in a subpile room beneath the pressure vessel. These features provide the necessary shielding for working above the reactor core and greatly facilitate access to the pressure vessel, core, and reflector regions. In-core irradiation and experiment locations (cross section at horizontal midplane) Reactor core assembly Reactor core assembly: (1) in-core irradiation and experiment locations,

271

SECA Core Technology Program Seal Workshop  

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

SECA Core Technology Program Seal Workshop Workshop held at Hyatt Regency, San Antonio August 10, 2007 Workshop organized by: Dr. Ayyakkannu Manivannan, National Energy technology Laboratory Morgantown, WV Dr. Prabhakar Singh Pacific Northwest National Laboratory Richland, WA 1 2 Table of Content * Executive Summary * Meeting Agenda * Presentations * List of Attendees 3 Executive Summary SECA Core Technology Program (SECA CTP) led workshop on the topical area titled "SOFC seal: Technology, Challenges and Future Directions" was held on August 10, 2007 at Hyatt Regency, San Antonio, TX. The workshop was attended by scientists and engineers presently involved in the development, engineering, fabrication, and testing of

272

Thermal metastabilities in the solar core  

E-Print Network (OSTI)

Linear stability analysis indicates that solar core is thermally stable for infinitesimal internal perturbations. For the first time, thermal metastabilities are found in the solar core when outer perturbations with significant amplitude are present. The obtained results show that hot bubbles generated by outer perturbations may travel a significant distance in the body of the Sun. These deep-origin hot bubbles have mass, energy, and chemical composition that may be related to solar flares. The results obtained may have remarkable relations to activity cycles in planets like Jupiter and also in extrasolar planetary systems.

Attila Grandpierre; Gabor Agoston

2002-01-18T23:59:59.000Z

273

Development of integrated core disruptive accident analysis code for FBR - ASTERIA-FBR  

SciTech Connect

The evaluation of consequence at the severe accident is the most important as a safety licensing issue for the reactor core of liquid metal cooled fast breeder reactor (LMFBR), since the LMFBR core is not in an optimum condition from the viewpoint of reactivity. This characteristics might induce a super-prompt criticality due to the core geometry change during the core disruptive accident (CDA). The previous CDA analysis codes have been modeled in plural phases dependent on the mechanism driving a super-prompt criticality. Then, the following event is calculated by connecting different codes. This scheme, however, should introduce uncertainty and/or arbitrary to calculation results. To resolve the issues and obtain the consistent calculation results without arbitrary, JNES is developing the ASTERIA-FBR code for the purpose of providing the cross-check analysis code, which is another required scheme to confirm the validity of the evaluation results prepared by applicants, in the safety licensing procedure of the planned high performance core of Monju. ASTERIA-FBR consists of the three major calculation modules, CONCORD, dynamic-GMVP, and FEMAXI-FBR. CONCORD is a three-dimensional thermal-hydraulics calculation module with multi-phase, multi-component, and multi-velocity field model. Dynamic-GMVP is a space-time neutronics calculation module. FEMAXI-FBR calculates the fuel pellet deformation behavior and fuel pin failure behavior. This paper describes the needs of ASTERIA-FBR development, major module outlines, and the model validation status. (authors)

Ishizu, T.; Endo, H.; Tatewaki, I.; Yamamoto, T. [Japan Nuclear Energy Safety Organization JNES, Toranomon Towers Office, 4-1-28, Toranomon, Minato-ku, Tokyo (Japan); Shirakawa, N. [Inst. of Applied Energy IAE, Shimbashi SY Bldg., 14-2 Nishi-Shimbashi 1-Chome, Minato-ku, Tokyo (Japan)

2012-07-01T23:59:59.000Z

274

Germania-Based Core Optical Fibers  

Science Journals Connector (OSTI)

Germania-glass-based core silica glass cladding single-mode fibers (Delta n up to 0.143) with a minimum loss of 20 dB/km at 1.9 µm were fabricated by the modified chemical vapor...

Dianov, Evgeny M; Mashinsky, Valery M

2005-01-01T23:59:59.000Z

275

Introduction What is the Common Core Curriculum?  

E-Print Network (OSTI)

been, and continue to be, of deeply profound significance to humankind, the core intellectual skills education, it is important that you choose your courses carefully. To this end, the handbook provides you. These learning outcomes are statements that specify precisely what you should be able to do at the end

Leung, Ka-Cheong

276

Introduction What is the Common Core Curriculum?  

E-Print Network (OSTI)

, it is important that you choose your courses carefully. To this end, the handbook provides you with detailed profound significance to humankind, the core intellectual skills that all HKU undergraduates should acquire are statements that specify precisely what you should be able to do at the end of a course, usually expressed

Leung, Ka-Cheong

277

Improving the economics of PWR cores  

SciTech Connect

Economic fuel cycles have become of paramount importance to the nuclear power industry due to the increasing impact of deregulation and competition. This paper describes the PWR core design techniques being employed at Entergy in the quest to meet the ever-decreasing fuel cost targets for these units.

Ober, T.G. [Entergy Operations, Jackson, MS (United States)

1996-08-01T23:59:59.000Z

278

Progress towards accelerating HOMME on hybrid multi- core systems  

SciTech Connect

The suitability of a spectral element based dynamical core (HOMME) within the Community Atmospheric Model (CAM) for GPU-based architectures is examined and initial performance results are reported. This work was done within a project to enable CAM to run at high resolution on next generation, multi-petaflop systems. The dynamical core is the present focus because it dominates the performance profile of our target problem. HOMME enjoys good scalability due to its underlying cubed-sphere mesh with full two-dimensional decomposition and the localization of all computational work within each element. The thread blocking and code changes that allow HOMME to effectively use GPUs are described along with a rewritten vertical remapping scheme which improves performance on both CPUs and GPUs. Validation of results in the full HOMME model is also described. Remaining issues affecting performance include optimizing the boundary exchanges for the case of multiple spectral elements being computed on the GPU and using multiple CUDA streams to overlap data transfers with computations.

Archibald, Richard K [ORNL; Carpenter, Ilene L [ORNL; Evans, Katherine J [ORNL; Larkin, Jeff [Cray, Inc.; Micikevicius, Paulius [ORNL; Rosinski, James [NOAA, Boulder, CO; Schwarzmeier, James L [ORNL; Taylor, Mark [Sandia National Laboratories (SNL)

2011-01-01T23:59:59.000Z

279

INTERPLAY OF NEUTRINO OPACITIES IN CORE-COLLAPSE SUPERNOVA SIMULATIONS  

SciTech Connect

We have conducted a series of numerical experiments using spherically symmetric, general relativistic, neutrino radiation hydrodynamics with the code Agile-BOLTZTRAN to examine the effects of modern neutrino opacities on the development of supernova simulations. We test the effects of opacities by removing opacities or by undoing opacity improvements for individual opacities and groups of opacities. We find that improvements to electron capture (EC) on nuclei, namely EC on an ensemble of nuclei using modern nuclear structure models rather than the simpler independent-particle approximation (IPA) for EC on a mean nucleus, plays the most important role during core collapse of all tested neutrino opacities. Low-energy neutrinos emitted by modern nuclear EC preferentially escape during collapse without the energy downscattering on electrons required to enhance neutrino escape and deleptonization for the models with IPA nuclear EC. During shock breakout the primary influence on the emergent neutrinos arises from non-isoenergetic scattering (NIS) on electrons. For the accretion phase, NIS on free nucleons and pair emission by e {sup +} e {sup -} annihilation have the largest impact on the neutrino emission and shock evolution. Other opacities evaluated, including nucleon-nucleon bremsstrahlung and especially neutrino-positron scattering, have little measurable impact on neutrino emission or shock dynamics. Modern treatments of nuclear EC, e {sup +} e {sup -}-annihilation pair emission, and NIS on electrons and free nucleons are critical elements of core-collapse simulations of all dimensionality.

Lentz, Eric J. [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Mezzacappa, Anthony; Hix, W. Raphael [Physics Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6354 (United States); Messer, O. E. Bronson [National Center for Computational Sciences, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6164 (United States); Bruenn, Stephen W., E-mail: elentz@utk.edu [Department of Physics, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431-0991 (United States)

2012-11-20T23:59:59.000Z

280

Neutrino-driven convection versus advection in core collapse supernovae  

E-Print Network (OSTI)

A toy model is analyzed in order to evaluate the linear stability of the gain region immediately behind a stalled accretion shock, after core bounce. This model demonstrates that a negative entropy gradient is not sufficient to warrant linear instability. The stability criterion is governed by the ratio \\chi of the advection time through the gain region divided by the local timescale of buoyancy. The gain region is linearly stable if \\chi3, perturbations are unstable in a limited range of horizontal wavelengths centered around twice the vertical size H of the gain region. The threshold horizontal wavenumbers k_{min} and k_{max} follow simple scaling laws such that Hk_{min}\\propto 1/{\\chi} and Hk_{max}\\propto \\chi. The convective stability of the l=1 mode in spherical accretion is discussed, in relation with the asymmetric explosion of core collapse supernovae. The advective stabilization of long wavelength perturbations weakens the possible influence of convection alone on a global l=1 mode.

T. Foglizzo; L. Scheck; H. -Th. Janka

2005-07-27T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

Quasi-geostrophic modes in the Earth's fluid core with an outer stably stratified layer  

E-Print Network (OSTI)

Seismic waves sensitive to the outermost part of the Earth's liquid core seem to be affected by a stably stratified layer at the core-mantle boundary. Such a layer could have an observable signature in both long-term and short-term variations of the magnetic field of the Earth, which are used to probe the flow at the top of the core. Indeed, with the recent SWARM mission, it seems reasonable to be able to identify waves propagating in the core with period of several months, which may play an important role in the large-scale dynamics. In this paper, we characterize the influence of a stratified layer at the top of the core on deep quasi-geostrophic (Rossby) waves. We compute numerically the quasi-geostrophic eigenmodes of a rapidly rotating spherical shell, with a stably stratified layer near the outer boundary. Two simple models of stratification are taken into account, which are scaled with commonly accepted values of the Brunt-V{\\"a}is{\\"a}l{\\"a} frequency in the Earth's core. In the absence of magnetic fi...

Vidal, Jérémie

2015-01-01T23:59:59.000Z

282

Density-based and transport-based core-periphery structures in networks  

Science Journals Connector (OSTI)

Networks often possess mesoscale structures, and studying them can yield insights into both structure and function. It is most common to study community structure, but numerous other types of mesoscale structures also exist. In this paper, we examine core-periphery structures based on both density and transport. In such structures, core network components are well-connected both among themselves and to peripheral components, which are not well-connected to anything. We examine core-periphery structures in a wide range of examples of transportation, social, and financial networks—including road networks in large urban areas, a rabbit warren, a dolphin social network, a European interbank network, and a migration network between counties in the United States. We illustrate that a recently developed transport-based notion of node coreness is very useful for characterizing transportation networks. We also generalize this notion to examine core versus peripheral edges, and we show that the resulting diagnostic is also useful for transportation networks. To examine the properties of transportation networks further, we develop a family of generative models of roadlike networks. We illustrate the effect of the dimensionality of the embedding space on transportation networks, and we demonstrate that the correlations between different measures of coreness can be very different for different types of networks.

Sang Hoon Lee; Mihai Cucuringu; Mason A. Porter

2014-03-20T23:59:59.000Z

283

Core Collapse Supernovae --- Theory between Achievements and New Challenges  

E-Print Network (OSTI)

Multi-dimensional hydrodynamic simulations of the post-bounce evolution of collapsed stellar iron cores have demonstrated that convective overturn between the stalled shock and the neutrinosphere can have an important effect on the neutrino-driven explosion mechanism. Whether a model yields a successful explosion or not, however, still depends on the power of neutrino energy deposition behind the stalled shock. The neutrino interaction with the stellar gas in the ``hot bubble'' also determines the duration of the shock stagnation phase, the explosion energy, and the composition of the neutrino-heated supernova ejecta. More accurate models require a more precise calculation of the neutrino luminosities and spectra and of the angular distributions of the neutrinos in the heating region. Therefore it is necessary to improve the numerical treatment of the neutrino transport, to develop a better understanding of the neutrino opacities of the dense nuclear medium, and to take into account convective processes {\\it inside} the newly formed neutron star.

H. -Th. Janka

1998-10-05T23:59:59.000Z

284

The Structure and Dark Halo Core Properties of Dwarf Spheroidal Galaxies  

E-Print Network (OSTI)

The structure and dark matter halo core properties of dwarf spheroidal galaxies (dSphs) are investigated. A double-isothermal model of an isothermal stellar system, embedded in an isothermal dark halo core provides an excellent fit to the various observed stellar surface density distributions. The stellar system can be well characterised by King profiles with a broad distribution of concentration parameters c. The core scale length of the stellar system a_* is sensitive to the central dark matter density rho_0. In contrast to single-component systems, the cut-off radius of the stellar system, rs_t, however does not trace the tidal radius but the core radius r_c of its dark matter halo. c is therefore sensitive to the ratio of the stellar to the dark matter velocity dispersion, sigma_*/sigma_0. Simple empirical relationships are derived that allow to calculate the dark halo core parameters rho_0, r_c and sigma_0, given the observable quantities sigma_*, a_* and c. The DIS model is applied to the Milky Way's dS...

Burkert, Andreas

2015-01-01T23:59:59.000Z

285

A WYSIWYG approach for configuring model layout using model transformations  

Science Journals Connector (OSTI)

Model transformation is a core technology in Domain-Specific Modeling (DSM). While a number of model transformation languages and tools have been developed to support model transformation activities, the layout of visual models in the transformation ... Keywords: demonstration, model layout, model transformation

Yu Sun; Jeff Gray; Philip Langer; Manuel Wimmer; Jules White

2010-10-01T23:59:59.000Z

286

Assessment of CRBR core disruptive accident energetics  

SciTech Connect

The results of an independent assessment of core disruptive accident energetics for the Clinch River Breeder Reactor are presented in this document. This assessment was performed for the Nuclear Regulatory Commission under the direction of the CRBR Program Office within the Office of Nuclear Reactor Regulation. It considered in detail the accident behavior for three accident initiators that are representative of three different classes of events; unprotected loss of flow, unprotected reactivity insertion, and protected loss of heat sink. The primary system's energetics accommodation capability was realistically, yet conservatively, determined in terms of core events. This accommodation capability was found to be equivalent to an isentropic work potential for expansion to one atmosphere of 2550 MJ or a ramp rate of about 200 $/s applied to a classical two-phase disassembly.

Theofanous, T.G.; Bell, C.R.

1984-03-01T23:59:59.000Z

287

Improvements in EBR-2 core depletion calculations  

SciTech Connect

The need for accurate core depletion calculations in Experimental Breeder Reactor No. 2 (EBR-2) is discussed. Because of the unique physics characteristics of EBR-2, it is difficult to obtain accurate and computationally efficient multigroup flux predictions. This paper describes the effect of various conventional and higher order schemes for group constant generation and for flux computations; results indicate that higher-order methods are required, particularly in the outer regions (i.e. the radial blanket). A methodology based on Nodal Equivalence Theory (N.E.T.) is developed which allows retention of the accuracy of a higher order solution with the computational efficiency of a few group nodal diffusion solution. The application of this methodology to three-dimensional EBR-2 flux predictions is demonstrated; this improved methodology allows accurate core depletion calculations at reasonable cost. 13 refs., 4 figs., 3 tabs.

Finck, P.J.; Hill, R.N.; Sakamoto, S.

1991-01-01T23:59:59.000Z

288

MOX fuel arrangement for nuclear core  

DOE Patents (OSTI)

In order to use up a stockpile of weapons-grade plutonium, the plutonium is converted into a mixed oxide (MOX) fuel form wherein it can be disposed in a plurality of different fuel assembly types. Depending on the equilibrium cycle that is required, a predetermined number of one or more of the fuel assembly types are selected and arranged in the core of the reactor in accordance with a selected loading schedule. Each of the fuel assemblies is designed to produce different combustion characteristics whereby the appropriate selection and disposition in the core enables the resulting equilibrium cycle to closely resemble that which is produced using urania fuel. The arrangement of the MOX rods and burnable absorber rods within each of the fuel assemblies, in combination with a selective control of the amount of plutonium which is contained in each of the MOX rods, is used to tailor the combustion characteristics of the assembly.

Kantrowitz, Mark L. (Portland, CT); Rosenstein, Richard G. (Windsor, CT)

2001-07-17T23:59:59.000Z

289

Mox fuel arrangement for nuclear core  

DOE Patents (OSTI)

In order to use up a stockpile of weapons-grade plutonium, the plutonium is converted into a mixed oxide (MOX) fuel form wherein it can be disposed in a plurality of different fuel assembly types. Depending on the equilibrium cycle that is required, a predetermined number of one or more of the fuel assembly types are selected and arranged in the core of the reactor in accordance with a selected loading schedule. Each of the fuel assemblies is designed to produce different combustion characteristics whereby the appropriate selection and disposition in the core enables the resulting equilibrium cycle to closely resemble that which is produced using urania fuel. The arrangement of the MOX rods and burnable absorber rods within each of the fuel assemblies, in combination with a selective control of the amount of plutonium which is contained in each of the MOX rods, is used to tailor the combustion. characteristics of the assembly.

Kantrowitz, Mark L. (Portland, CT); Rosenstein, Richard G. (Windsor, CT)

2001-05-15T23:59:59.000Z

290

MOX fuel arrangement for nuclear core  

DOE Patents (OSTI)

In order to use up a stockpile of weapons-grade plutonium, the plutonium is converted into a mixed oxide (MOX) fuel form wherein it can be disposed in a plurality of different fuel assembly types. Depending on the equilibrium cycle that is required, a predetermined number of one or more of the fuel assembly types are selected and arranged in the core of the reactor in accordance with a selected loading schedule. Each of the fuel assemblies is designed to produce different combustion characteristics whereby the appropriate selection and disposition in the core enables the resulting equilibrium cycle to closely resemble that which is produced using urania fuel. The arrangement of the MOX rods and burnable absorber rods within each of the fuel assemblies, in combination with a selective control of the amount of plutonium which is contained in each of the MOX rods, is used to tailor the combustion characteristics of the assembly. 38 figs.

Kantrowitz, M.L.; Rosenstein, R.G.

1998-10-13T23:59:59.000Z

291

MOX fuel arrangement for nuclear core  

DOE Patents (OSTI)

In order to use up a stockpile of weapons-grade plutonium, the plutonium is converted into a mixed oxide (MOX) fuel form wherein it can be disposed in a plurality of different fuel assembly types. Depending on the equilibrium cycle that is required, a predetermined number of one or more of the fuel assembly types are selected and arranged in the core of the reactor in accordance with a selected loading schedule. Each of the fuel assemblies is designed to produce different combustion characteristics whereby the appropriate selection and disposition in the core enables the resulting equilibrium cycle to closely resemble that which is produced using urania fuel. The arrangement of the MOX rods and burnable absorber rods within each of the fuel assemblies, in combination with a selective control of the amount of plutonium which is contained in each of the MOX rods, is used to tailor the combustion characteristics of the assembly.

Kantrowitz, Mark L. (Portland, CT); Rosenstein, Richard G. (Windsor, CT)

1998-01-01T23:59:59.000Z

292

Next Generation CANDU Core Physics Innovations  

SciTech Connect

NG CANDU is the 'Next Generation' CANDU{sup R} reactor, aimed at producing electrical power at a capital cost significantly less than that of the current reactor designs. A key element of cost reduction is the use of H{sub 2}O as coolant and Slightly Enriched Uranium fuel in a tight D{sub 2}O-moderated lattice. The innovations in the CANDU core physics result in substantial improvements in economics as well as significant enhancements in reactor licensability, controllability, and waste reduction. The full-core coolant-void reactivity in NG CANDU is about -3 mk. Power coefficient is substantially negative. Fuel burnup is about three times the current natural-uranium burnup. (authors)

Chan, P.S.W.; Hopwood, J.M.; Love, J.W. [Atomic Energy of Canada Ltd., Ontario (Canada)

2002-07-01T23:59:59.000Z

293

ARM - Field Campaign - Observations and Modeling of the Green...  

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

integrated into the larger Brazilian Earth System Model (BESM) and several US Earth System Models. This research provides results that directly contribute to DOE's Atmospheric...

294

The Oxygen core inside the Magnesium isotopes  

E-Print Network (OSTI)

We have studied the ground state bulk properties of magnesium isotopes using axially symmetric relativistic mean field formalism. The BCS pairing approach is employed to take care of the pairing correlation for the open shell nuclei. The contour plot of the nucleons distribution are analyzed at various parts of the nucleus, where clusters are located. The presence of an $^{16}$O core along bubble like $\\alpha$-particle(s) and few {\\it nucleons} are found in the Mg isotopes.

Bhuyan, M

2013-01-01T23:59:59.000Z

295

PSYCHOLOGY MAJOR -EFFECTIVE FALL 2012 Core Requirements MUST earn a grade C or better in each  

E-Print Network (OSTI)

PSYCHOLOGY MAJOR - EFFECTIVE FALL 2012 Core Requirements ­ MUST earn a grade C or better in each Areas of Study: Area 1: Basic Psychological Processes ­ Choose TWO courses Course Title Units Completed Motivation PSY 494 Cognitive Psychology PSY 496 Cognitive Science: Models of Human Psychology PSY 498

296

Designing a New Fuel for HFIR-Performance Parameters for LEU Core Configurations  

SciTech Connect

An engineering design study for a fuel that would enable the conversion of the High Flux Isotope Reactor from highly enriched uranium to low enriched uranium fuel is ongoing as part of an effort sponsored by the U.S. Department of Energy's National Nuclear Security Administration through the Global Threat Reduction Initiative. Given the unique fuel and core design and high power density of the reactor and the requirement that the impact of the fuel change on the core performance and operation be minimal, this conversion study presents a complex and challenging task, requiring improvements in the computational models currently used to support the operation of the reactor and development of new models that would take advantage of newly available simulation methods and tools. The computational models used to search for a fuel design that would meet the requirements for the conversion study and the results obtained with these models are presented and discussed. Estimates of relevant reactor performance parameters for the low enriched uranium fuel core are presented and compared to the corresponding data for the currently operating highly enriched uranium fuel core.

Ilas, Germina [ORNL; Primm, Trent [ORNL; Gehin, Jess C [ORNL

2009-01-01T23:59:59.000Z

297

Numerical Age Computation of the Antarctic Ice Sheet for Dating Deep Ice Cores  

E-Print Network (OSTI)

Numerical Age Computation of the Antarctic Ice Sheet for Dating Deep Ice Cores Bernd M¨ugge1 for the computation of the age of ice is discussed within the frame of numerical ice sheet modelling. The first method of a numerical diffusion term to stabilize the solution and therefore produces arbitrary results in a near

Calov, Reinhard

298

Shear viscosity in neutron star cores  

E-Print Network (OSTI)

We calculate the shear viscosity $\\eta = \\eta_{e\\mu}+\\eta_{n}$ in a neutron star core composed of nucleons, electrons and muons ($\\eta_{e\\mu}$ being the electron-muon viscosity, mediated by collisions of electrons and muons with charged particles, and $\\eta_{n}$ the neutron viscosity, mediated by neutron-neutron and neutron-proton collisions). Deriving $\\eta_{e\\mu}$, we take into account the Landau damping in collisions of electrons and muons with charged particles via the exchange of transverse plasmons. It lowers $\\eta_{e\\mu}$ and leads to the non-standard temperature behavior $\\eta_{e\\mu}\\propto T^{-5/3}$. The viscosity $\\eta_{n}$ is calculated taking into account that in-medium effects modify nucleon effective masses in dense matter. Both viscosities, $\\eta_{e\\mu}$ and $\\eta_{n}$, can be important, and both are calculated including the effects of proton superfluidity. They are presented in the form valid for any equation of state of nucleon dense matter. We analyze the density and temperature dependence of $\\eta$ for different equations of state in neutron star cores, and compare $\\eta$ with the bulk viscosity in the core and with the shear viscosity in the crust.

P. S. Shternin; D. G. Yakovlev

2008-08-14T23:59:59.000Z

299

Design exploration: engaging a larger user population  

E-Print Network (OSTI)

in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved: Chair of Committee, Frank M. Shipman, III Committee Members, Richard K. Furuta William Lively Steven Smith Head of Department, Valerie Taylor... Committee: Dr. Frank M. Shipman, III Software designers must understand the domain, work practices, and user expectations before determining requirements or generating initial design mock-ups. Users and other stakeholders are a valuable source...

Moore, John Michael

2009-06-02T23:59:59.000Z

300

More ‘altruistic’ punishment in larger societies  

Science Journals Connector (OSTI)

...methods In the cross-cultural project, three experimental economics...of impositions on individual liberty are unimaginable in some small-scale...third parties. Individual liberty can coexist with a good deal...data from the cross-cultural project, as well as all the individual...

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

Larger diverters safer for shallow gas control  

SciTech Connect

This paper reports on reducing the back pressure buildup on the wellhead during shallow gas control which minimizes the risk of the gas broaching the seabed around the conductor pipe. This allows for an orderly procedure to divert the gas. Most diverter systems cause the gas/sand mixture to approach critical velocity, resulting in extreme wear and short life expectancy of the surface piping. Calculations based on standard drilling programs indicate that only a few existing diverter systems can handle a sizeable volume of shallow gas without creating excess back pressure on the wellhead.

Mills, D. (Glasgow Polytechnic, Glasgow (GB)); Dyhr, E. (Copeman Engineering, Copenhagen (DK))

1991-12-02T23:59:59.000Z

302

STRUCTURE OF THE SUN'S CORE: EVOLUTIONAL AND SEISMOLOGICAL CONSTRAINTS  

E-Print Network (OSTI)

­generating core where the thermonuclear reactions are significant; there is definitely variable hydrogen approximate, of course. We set the core's upper boundary at 10 million K assuming that thermonuclear reactions

303

High voltage dry-type air-core shunt reactors  

Science Journals Connector (OSTI)

Dry-type air-core shunt reactors are now being ... systems to limit overvoltages. Recently, high voltage dry-type air-core shunt reactors have been designed, ... transient overvoltages and electrical and magnetic...

Klaus Papp; Michael R. Sharp…

2014-11-01T23:59:59.000Z

304

Armored spring-core superconducting cable and method of construction  

DOE Patents (OSTI)

An armored spring-core superconducting cable (12) is provided. The armored spring-core superconducting cable (12) may include a spring-core (20), at least one superconducting strand (24) wound onto the spring-core (20), and an armored shell (22) that encases the superconducting strands (24). The spring-core (20) is generally a perforated tube that allows purge gases and cryogenic liquids to be circulated through the armored superconducting cable (12), as well as managing the internal stresses within the armored spring-core superconducting cable (12). The armored shell (22) manages the external stresses of the armored spring-core superconducting cable (12) to protect the fragile superconducting strands (24). The armored spring-core superconducting cable (12) may also include a conductive jacket (34) formed outwardly of the armored shell (22).

McIntyre, Peter M. (611 Montclair, College Station, TX 77840); Soika, Rainer H. (1 Hensel, #X4C, College Station, TX 77840)

2002-01-01T23:59:59.000Z

305

Protein folding mediated by solvation: water expelling and formation of the hydrophobic core occurs after the structure collapse  

E-Print Network (OSTI)

The interplay between structure-search of the native structure and desolvation in protein folding has been explored using a minimalist model. These results support a folding mechanism where most of the structural formation of the protein is achieved before water is expelled from the hydrophobic core. This view integrates water expulsion effects into the funnel energy landscape theory of protein folding. Comparisons to experimental results are shown for the SH3 protein. After the folding transition, a near-native intermediate with partially solvated hydrophobic core is found. This transition is followed by a final step that cooperatively squeezes out water molecules from the partially hydrated protein core.

Margaret S. Cheung; Angel E. Garcia; Jose N. Onuchic

2002-03-31T23:59:59.000Z

306

Neutrino-driven supernova of a low-mass iron-core progenitor boosted by three-dimensional turbulent convection  

E-Print Network (OSTI)

We present the first successful simulation of a neutrino-driven supernova explosion in three dimensions (3D), using the Prometheus-Vertex code with an axis-free Yin-Yang grid and a sophisticated treatment of three-flavor, energy-dependent neutrino transport. The progenitor is a non-rotating, zero-metallicity 9.6 Msun star with an iron core. While in spherical symmetry outward shock acceleration sets in later than 300 ms after bounce, a successful explosion starts at ~130 ms post-bounce in two dimensions (2D). The 3D model explodes at about the same time but with faster shock expansion than in 2D and a more quickly increasing and roughly 10 percent higher explosion energy. The more favorable explosion conditions in 3D are explained by lower temperatures and thus reduced neutrino emission in the cooling layer below the gain radius. This moves the gain radius inward and leads to a bigger mass in the gain layer, whose larger recombination energy boosts the explosion energy in 3D. These differences are caused by less coherent, less massive, and less rapid convective downdrafts associated with post-shock convection in 3D. The less violent impact of these accretion downflows in the cooling layer produces less dissipative heating and therefore diminishes energy losses by neutrino emission. We thus have, for the first time, identified a reduced mass accretion rate, lower infall velocities, and a smaller surface filling factor of convective downdrafts as consequences of 3D postshock turbulence that facilitate neutrino-driven explosions and strengthen them compared to the 2D case.

Tobias Melson; Hans-Thomas Janka; Andreas Marek

2015-01-08T23:59:59.000Z

307

THERMAL PROPERTIES OF GABLE MOUNTAIN BASALT CORES HANFORD NUCLEAR RESERVATION  

E-Print Network (OSTI)

1974. 7. Atlantic Richfield Hanford Company, Research andGABLE MOUNTAIN BASALT CORES HANFORD NUCLEAR RESERVATION L.

Martinez-Baez, L.F.

2011-01-01T23:59:59.000Z

308

Core Internal Transport Barriers in Alcator C-Mod  

E-Print Network (OSTI)

-Mod Group Supported by DoE grant DE-FC02-99ER54512 #12;Alcator C-Mod Introduction Core Internal TransportAlcator C-Mod Core Internal Transport Barriers in Alcator C-Mod Catherine Fiore MIT Plasma Science types of core ITBs in Alcator C-Mod. Off-Axis ICRF generated core ITBs Spontaneous ITBs at H- to L

Fiore, Catherine L.

309

CSAT Role-Based/Core Competency Training Program  

Energy.gov (U.S. Department of Energy (DOE))

To provide information on available role-based/core competency training modules via OLC for significant cyber roles.

310

Cores and cusps in warm dark matter halos  

SciTech Connect

The apparent presence of large core radii in Low Surface Brightness galaxies has been claimed as evidence in favor of warm dark matter. Here we show that WDM halos do not have cores that are large fractions of the halo size: typically, r{sub core}/r{sub 200}?<10{sup ?3}. This suggests an astrophysical origin for the large cores observed in these galaxies, as has been argued by other authors.

Villaescusa-Navarro, Francisco [IFIC, Universidad de Valencia-CSIC, E-46071, Valencia (Spain); Dalal, Neal, E-mail: villa@ific.uv.es, E-mail: neal@cita.utoronto.ca [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George St., Toronto, ON, M5S3H8 (Canada)

2011-03-01T23:59:59.000Z

311

Impact of the symmetry energy on nuclear pasta phases and crust-core transition in neutron stars  

E-Print Network (OSTI)

We study the impact of the symmetry energy on properties of nuclear pasta phases and crust-core transition in neutron stars. We perform a self-consistent Thomas--Fermi calculation employing the relativistic mean-field model. The properties of pasta phases presented in the inner crust of neutron stars are investigated and the crust-core transition is examined. It is found that the slope of the symmetry energy plays an important role in determining the pasta phase structure and the crust-core transition. The correlation between the symmetry energy slope and the crust-core transition density obtained in the Thomas--Fermi approximation is consistent with that predicted by the liquid-drop model.

Bao, S S

2015-01-01T23:59:59.000Z

312

DIMENSIONAL DEPENDENCE OF THE HYDRODYNAMICS OF CORE-COLLAPSE SUPERNOVAE  

SciTech Connect

A major goal over the last decade has been understanding which multidimensional effects are crucial in facilitating core-collapse supernova (CCSN) explosions. Unfortunately, much of this work has necessarily assumed axisymmetry. In this work, we present analyses of simplified two-dimensional (2D) and three-dimensional (3D) CCSN models with the goal of comparing the hydrodynamics in setups that differ only in dimension. Not surprisingly, we find many differences between 2D and 3D models. While some differences are subtle and perhaps not crucial, others are dramatic and make interpreting 2D models problematic. In particular, axisymmetric models produce excess power at the largest spatial scales, power that has been deemed critical in previous explosion models. Nevertheless, our 3D models, which have an order of magnitude less power than 2D models on large scales, explode earlier. Since explosions occur earlier in 3D than in 2D, the vigorous large-scale sloshing is either not critical in any dimension or the explosion mechanism operates differently in 2D and 3D. On the other hand, we find that the average parcel of matter in the gain region has been exposed to net heating for up to 30% longer in 3D than in 2D, an effect we attribute to the differing characters of turbulence in 2D and 3D. We suggest that this effect plays a prominent role in producing earlier explosions in 3D. Finally, we discuss a simple model for the runaway growth of buoyant bubbles that is able to quantitatively account for the growth of the shock radius and predicts a critical luminosity relation.

Dolence, Joshua C.; Burrows, Adam; Murphy, Jeremiah W. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Nordhaus, Jason, E-mail: jdolence@astro.princeton.edu, E-mail: burrows@astro.princeton.edu, E-mail: jmurphy@astro.princeton.edu, E-mail: nordhaus@astro.rit.edu [Center for Computational Relativity and Gravitation, Rochester Institute of Technology, Rochester, NY 14623 (United States)

2013-03-10T23:59:59.000Z

313

Gas-like state of $?$ clusters around $^{16}$O core in $^{24}$Mg  

E-Print Network (OSTI)

We have studied gas-like states of $\\alpha$ clusters around an $^{16}$O core in $^{24}$Mg based on a microscopic $\\alpha$-cluster model. This study was performed by introducing a Monte Carlo technique for the description of the THSR (Tohsaki Horiuchi Schuck R\\"{o}pke) wave function, and the coupling effect to other low-lying cluster states was taken into account. A large isoscalar monopole ($E0$) transition strength from the ground to the gas-like state is discussed. The gas-like state of two $\\alpha$ clusters in $^{24}$Mg around the $^{16}$O core appears slightly below the 2$\\alpha$-threshold e

T. Ichikawa; N. Itagaki; T. Kawabata; Tz. Kokalova; W. von Oertzen

2011-02-08T23:59:59.000Z

314

Three-dimensional antenna coupling to core plasma in fusion devices  

SciTech Connect

A complete understanding of the RF physics from the launcher to the plasma core is required to fully analyze RF experiments and to evaluate the performance of RF antenna designs in ITER. This understanding requires a consistent model for the RF power launching system, propagation and absorption through the edge region, and the response of the core plasma to the RF power. As a first step toward such a model, the three-dimensional (3D) antenna modeling code, RANT3D, has been coupled with the reduced order full wave code, PICES. Preliminary results from this model are presented in this paper for parameters similar to those found in the DIII-D experiment.

Carter, M.D.; Jaeger, E.F.; Stallings, D.C.; Galambos, J.D.; Batchelor, D.B.; Wang, C.Y.

1995-09-01T23:59:59.000Z

315

Analysis of Sandwich Shells with Metallic Foam Cores based on the Uniaxial Tensile Test  

SciTech Connect

On this work, the authors present the development and evaluation of an innovative system able to perform reliable panels of sandwich sheets with metallic foam cores for industrial applications, especially in automotive and aeronautical industries. This work is divided into two parts; in the first part the mathematical model used to describe the behavior of sandwich shells with metal cores form is presented and some numerical examples are presented. In the second part of this work, the numerical results are validated using the experimental results obtained from the mechanical experiments. Using the isotropic hardening crushable foam constitutive model, available on ABAQUS, a set of different mechanical tests were simulated. The isotropic hardening model available uses a yield surface that is an ellipse centered at the origin in the p-q stress plane. Using this constitutive model, the uniaxial tensile test for this material was simulated, and a comparison with the experimental results was made.

Mata, H.; Fernandes, A. A.; Parente, M. P. L.; Jorge, R. Natal [IDMEC-FEUP, Rua Dr. Roberto Frias, 4200-465, Porto (Portugal); Santos, A. [INEGI, Rua Dr. Roberto Frias, 4200-465, Porto (Portugal); Valente, R. A. F. [Universidade de Aveiro, Campus Universitario de Santiago, 3810-193, Aveiro (Portugal)

2011-05-04T23:59:59.000Z

316

Ex-Core CFD Analysis Results for the Prometheus Gas Reactor  

SciTech Connect

This paper presents the initial nozzle-to-nozzle (N2N) reactor vessel model scoping studies using computational fluid dynamics (CFD) analysis methods. The N2N model has been solved under a variety of different boundary conditions. This paper presents some of the basic hydraulic results from the N2N CFD analysis effort. It also demonstrates how designers were going to apply the analysis results to modify a number of the design features. The initial goals for developing a preliminary CFD N2N model were to establish baseline expectations for pressure drops and flow fields around the reactor core. Analysis results indicated that the averaged reactor vessel pressure drop for all analyzed cases was 46.9 kPa ({approx}6.8 psid). In addition, mass flow distributions to the three core fuel channel regions exhibited a nearly inverted profile to those specified for the in-core thermal/hydraulic design. During subsequent design iterations, the goal would have been to modify or add design features that would have minimized reactor vessel pressure drop and improved flow distribution to the inlet of the core.

Lorentz, Donald G. [Space Engineering, Bechtel Bettis, Inc. West Mifflin, PA 15122 (United States)

2007-01-30T23:59:59.000Z

317

Critical core mass for enriched envelopes: the role of H2O condensation  

E-Print Network (OSTI)

Context. Within the core accretion scenario of planetary formation, most simulations performed so far always assume the accreting envelope to have a solar composition. From the study of meteorite showers on Earth and numerical simulations, we know that planetesimals must undergo thermal ablation and disruption when crossing a protoplanetary envelope. Once the protoplanet has acquired an atmosphere, the primordial envelope gets enriched in volatiles and silicates from the planetesimals. This change of envelope composition during the formation can have a significant effect in the final atmospheric composition and on the formation timescale of giant planets. Aims. To investigate the physical implications of considering the envelope enrichment of protoplanets due to the disruption of icy planetesimals during their way to the core. Particular focus is placed on the effect on the critical core mass for envelopes where condensation of water can occur. Methods. Internal structure models are numerically solved with th...

Venturini, J; Benz, W; Ikoma, M

2015-01-01T23:59:59.000Z

318

Fast spectrum space reactor sizing code for calandria-type cores (CORSCO Code). [Li  

SciTech Connect

The CORSCO code rapidly sizes reactor cores that have calandria-type geometry. The fuel configuration modeled is a large ceramic zone that contains numerous small cylindrical coolant channels spaced apart with a triangular pitch. A minimum reactor weight is obtained for a fixed set of constraints (peak fuel temperature, peak coolant velocity, etc.) by obtaining a unique solution to a set of five thermal/hydraulic equations, as well as a required excess reactivity which is specified by a core size dependent one-group criticality expression. Typical results are shown for a W-Re/UN cermet-fueled, lithium-cooled space reactor over a power range of 25 to 100 MWt. Reactor sensitivity coefficients are also shown for changes in reactor weight and number of coolant channels due to changes in core thermal/hydraulic constraints.

Specht, E.R.; Villalobos, A. (Rockwell International, Rocketdyne Division, 6633 Canoga Avenue, HB23, Canoga Park, California (USA))

1991-01-10T23:59:59.000Z

319

Diffusion Enhancement in Core-softened fluid confined in nanotubes  

E-Print Network (OSTI)

We study the effect of confinement in the dynamical behavior of a core-softened fluid. The fluid is modeled as a two length scales potential. This potential in the bulk reproduces the anomalous behavior observed in the density and in the diffusion of liquid water. A series of $NpT$ Molecular Dynamics simulations for this two length scales fluid confined in a nanotube were performed. We obtain that the diffusion coefficient increases with the increase of the nanotube radius for wide channels as expected for normal fluids. However, for narrow channels, the confinement shows an enhancement in the diffusion coefficient when the nanotube radius decreases. This behavior, observed for water, is explained in the framework of the two length scales potential.

José R. Bordin; Alan B. de Oliveira; Alexandre Diehl; Marcia C. Barbosa

2012-08-05T23:59:59.000Z

320

Assessment of WIMS-AECL/RFSP for CANDU core analysis  

SciTech Connect

The code system used for the design of, currently operating Canada deuterium uranium (CANDU) reactors consists of the cell code POWDERPUFS-V and the finite difference code RFSP. The use of POWDERPUFS-V is limited to natural uranium fuel because of the empirical correlations implemented. For the advanced CANDU fuel cycle using spent pressurized water reactor fuel in CANDU (DUPIC), it is necessary to adopt a lattice code that has a general application in isotopics and geometry modeling. For the DUPIC fuel cycle, it was decided to use WIMS-AECL and RFSP for the lattice parameter generation and core simulation, respectively, with the ENDF/B-V nuclear data processed for WIMS-AECL by Atomic Energy of Canada (AECL).

Choi, Hangbok; Rhee, Bo W.; Park, Hyunsoo [Korea Atomic Energy Research Institute, Daejon (Korea, Democratic People`s Republic of)

1995-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

3D Modeling with Silhouettes  

E-Print Network (OSTI)

We present a new sketch-based modeling approach in which models are interactively designed by drawing their 2D silhouettes from different views. The core idea of our paper is to limit the input to 2D silhouettes, removing ...

Rivers, Alec Rothmyer

322

Investigation on the Core Bypass Flow in a Very High Temperature Reactor  

SciTech Connect

Uncertainties associated with the core bypass flow are some of the key issues that directly influence the coolant mass flow distribution and magnitude, and thus the operational core temperature profiles, in the very high-temperature reactor (VHTR). Designers will attempt to configure the core geometry so the core cooling flow rate magnitude and distribution conform to the design values. The objective of this project is to study the bypass flow both experimentally and computationally. Researchers will develop experimental data using state-of-the-art particle image velocimetry in a small test facility. The team will attempt to obtain full field temperature distribution using racks of thermocouples. The experimental data are intended to benchmark computational fluid dynamics (CFD) codes by providing detailed information. These experimental data are urgently needed for validation of the CFD codes. The following are the project tasks: • Construct a small-scale bench-top experiment to resemble the bypass flow between the graphite blocks, varying parameters to address their impact on bypass flow. Wall roughness of the graphite block walls, spacing between the blocks, and temperature of the blocks are some of the parameters to be tested. • Perform CFD to evaluate pre- and post-test calculations and turbulence models, including sensitivity studies to achieve high accuracy. • Develop the state-of-the art large eddy simulation (LES) using appropriate subgrid modeling. • Develop models to be used in systems thermal hydraulics codes to account and estimate the bypass flows. These computer programs include, among others, RELAP3D, MELCOR, GAMMA, and GAS-NET. Actual core bypass flow rate may vary considerably from the design value. Although the uncertainty of the bypass flow rate is not known, some sources have stated that the bypass flow rates in the Fort St. Vrain reactor were between 8 and 25 percent of the total reactor mass flow rate. If bypass flow rates are on the high side, the quantity of cooling flow through the core may be considerably less than the nominal design value, causing some regions of the core to operate at temperatures in excess of the design values. These effects are postulated to lead to localized hot regions in the core that must be considered when evaluating the VHTR operational and accident scenarios.

Hassan, Yassin

2013-10-22T23:59:59.000Z

323

Hunton Group core workshop and field trip  

SciTech Connect

The Late Ordovician-Silurian-Devonian Hunton Group is a moderately thick sequence of shallow-marine carbonates deposited on the south edge of the North American craton. This rock unit is a major target for petroleum exploration and reservoir development in the southern Midcontinent. The workshop described here was held to display cores, outcrop samples, and other reservoir-characterization studies of the Hunton Group and equivalent strata throughout the region. A field trip was organized to complement the workshop by allowing examination of excellent outcrops of the Hunton Group of the Arbuckle Mountains.

Johnson, K.S. [ed.

1993-12-31T23:59:59.000Z

324

The Thermal Mass limit of Neutron Cores  

E-Print Network (OSTI)

Static thermal equilibrium of a quantum self-gravitating ideal gas in General Relativity is studied at any temperature, taking into account the Tolman-Ehrenfest effect. Thermal contribution to the gravitational stability of static neutron cores is quantified. The curve of maximum mass with respect to temperature is reported. At low temperatures is recovered the Oppenheimer-Volkoff calculation, while at high temperatures is recovered the, recently reported, classical gas calculation. An ultimate upper mass limit $M = 2.43M_\\odot$ of all maximum values is found to occur at Tolman temperature $ T = 1.27mc^2$ with radius $R = 15.2km$.

Roupas, Zacharias

2014-01-01T23:59:59.000Z

325

Hydrogen issue in Core Collapse Supernovae  

E-Print Network (OSTI)

We discuss results of analyzing a time series of selected photospheric-optical spectra of core collapse supernovae (CCSNe). This is accomplished by means of the parameterized supernovae synthetic spectrum (SSp) code ``SYNOW''. Special attention is addressed to traces of hydrogen at early phases, especially for the stripped-envelope SNe (i.e. SNe Ib-c). A thin low mass hydrogen layer extending to very high ejection velocities above the helium shell, is found to be the most likely scenario for Type Ib SNe.

A. Elmhamdi; I. J. Danziger; D. Branch; B. Leibundgut

2006-11-06T23:59:59.000Z

326

Core transport studies in fusion devices  

E-Print Network (OSTI)

The turbulence in magnetically confined fusion plasmas has important and non-trivial effects on the quality of the energy confinement. These effects are hard to make a quantitative assessment of analytically. The problem investigated in this article is the transport of energy and particles, in particular impurities, in a Tokamak plasma. Impurities from the walls of the plasma vessel cause energy losses if they reach the plasma core. It is therefore important to understand the transport mechanisms to prevent impurity accumulation and minimize losses. This is an area of research where turbulence plays a major role and is intimately associated with the performance of future fusion reactors, such as ITER.

Strand, Pär; Nordman, Hans

2010-01-01T23:59:59.000Z

327

TMI-2 core damage: a summary of present knowledge  

SciTech Connect

Extensive fuel damage (oxidation and fragmentation) has occurred and the top approx. 1.5 m of the center portion of the TMI-2 core has relocated. The fuel fragmentation extends outward to slightly beyond one-half the core radius in the direction examined by the CCTV camera. While the radial extent of core fragmentation in other directions was not directly observed, control and spider drop data and in-core instrument data suggest that the core void is roughly symmetrical, although there are a few indications of severe fuel damage extending to the core periphery. The core material fragmented into a broad range of particle sizes, extending down to a few microns. APSR movement data, the observation of damaged fuel assemblies hanging unsupported from the bottom of the reactor upper plenum structure, and the observation of once-molten stainless steel immediately above the active core indicate high temperatures (up to at least 1720 K) extended to the very top of the core. The relative lack of damage to the underside of the plenum structure implies a sharp temperature demarcation at the core/plenum interface. Filter debris and leadscrew deposit analyses indicate extensive high temperature core materials interaction, melting of the Ag-In-Cd control material, and transport of particulate control material to the plenum and out of the vessel.

Owen, D.E.; Mason, R.E.; Meininger, R.D.; Franz, W.A.

1983-01-01T23:59:59.000Z

328

CoreFlow Scientific Solutions Ltd | Open Energy Information  

Open Energy Info (EERE)

CoreFlow Scientific Solutions Ltd CoreFlow Scientific Solutions Ltd Jump to: navigation, search Name CoreFlow Scientific Solutions Ltd Place Yoqneam, Israel Zip 20692 Sector Solar Product Israel-based manufacturer of non-contact substrate processing, handling, and testing equipments for Flat Panel Display (FPD), semiconductor, and solar industries. References CoreFlow Scientific Solutions Ltd[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. CoreFlow Scientific Solutions Ltd is a company located in Yoqneam, Israel . References ↑ "CoreFlow Scientific Solutions Ltd" Retrieved from "http://en.openei.org/w/index.php?title=CoreFlow_Scientific_Solutions_Ltd&oldid=343913" Categories:

329

3D Numerical Experimentation on the Core Helium Flash of low-mass Red Giants  

E-Print Network (OSTI)

We model the core helium flash in a low-mass red giant using Djehuty, a fully three-dimensional (3D) code. The 3D structures were generated from converged models obtained during the 1D evolutionary calculation of a 1$\\Msun$ star. Independently of which starting point we adopted, we found that after some transient relaxation the 3D model settled down with a briskly convecting He-burning shell that was not very different from what the 1D model predicted.

David S. P. Dearborn; John C. Lattanzio; Peter P. Eggleton

2005-12-02T23:59:59.000Z

330

Modeling  

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

a single-fluid diffuse interface model in the ALE-AMR hydrodynamics code to simulate surface tension effects. We show simula- tions and compare them to other surface tension...

331

Modeling  

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

sion effects. We show the result of a test case, and compare it to the result without surface tension. The model describes droplet formation nicely. Application The ARRA-funded...

332

Heat transfer in sunspot penumbrae. Origin of dark-cored penumbral filaments  

E-Print Network (OSTI)

Context: Observations at 0.1" have revealed the existence of dark cores in the bright filaments of sunspot penumbrae. Expectations are high that such dark-cored filaments are the basic building blocks of the penumbra, but their nature remains unknown. Aims: We investigate the origin of dark cores in penumbral filaments and the surplus brightness of the penumbra. To that end we use an uncombed penumbral model. Methods: The 2D stationary heat transfer equation is solved in a stratified atmosphere consisting of nearly horizontal magnetic flux tubes embedded in a stronger and more vertical field. The tubes carry an Evershed flow of hot plasma. Results: This model produces bright filaments with dark cores as a consequence of the higher density of the plasma inside the tubes, which shifts the surface of optical depth unity toward higher (cooler) layers. Our calculations suggest that the surplus brightness of the penumbra is a natural consequence of the Evershed flow, and that magnetic flux tubes about 250 km in diameter can explain the morphology of sunspot penumbrae.

B. Ruiz Cobo; L. R. Bellot Rubio

2008-10-07T23:59:59.000Z

333

Framework Application for Core Edge Transport Simulation (FACETS)  

SciTech Connect

The goal of the FACETS project (Framework Application for Core-Edge Transport Simulations) was to provide a multiphysics, parallel framework application (FACETS) that will enable whole-device modeling for the U.S. fusion program, to provide the modeling infrastructure needed for ITER, the next step fusion confinement device. Through use of modern computational methods, including component technology and object oriented design, FACETS is able to switch from one model to another for a given aspect of the physics in a flexible manner. This enables use of simplified models for rapid turnaround or high-fidelity models that can take advantage of the largest supercomputer hardware. FACETS does so in a heterogeneous parallel context, where different parts of the application execute in parallel by utilizing task farming, domain decomposition, and/or pipelining as needed and applicable. ParaTools, Inc. was tasked with supporting the performance analysis and tuning of the FACETS components and framework in order to achieve the parallel scaling goals of the project. The TAU Performance System�������������������������������® was used for instrumentation, measurement, archiving, and profile / tracing analysis. ParaTools, Inc. also assisted in FACETS performance engineering efforts. Through the use of the TAU Performance System, ParaTools provided instrumentation, measurement, analysis and archival support for the FACETS project. Performance optimization of key components has yielded significant performance speedups. TAU was integrated into the FACETS build for both the full coupled application and the UEDGE component. The performance database provided archival storage of the performance regression testing data generated by the project, and helped to track improvements in the software development.

Dr. Allen D. Malony; Dr. Sameer S. Shende; Dr. Kevin A. Huck; Mr. Alan Morris, and Mr. Wyatt Spear

2012-03-14T23:59:59.000Z

334

Numerical Simulation of the Meso-? Scale Structure and Evolution of the 1977 Johnstown Flood. Part II: Inertially Stable Warm-Core Vortex and the Mesoscale Convective Complex  

Science Journals Connector (OSTI)

A mesoscale warm-core vortex associated with the mesoscale convective complex (MCC) that produced the 1977 Johnstown flood is examined using a three-dimensional nested-grid model simulation of the flood episode. In the simulation, the vortex ...

Da-Lin Zhang; J. Michael Fritsch

1987-09-01T23:59:59.000Z

335

Benchmark Evaluation of the NRAD Reactor LEU Core Startup Measurements  

SciTech Connect

The Neutron Radiography (NRAD) reactor is a 250-kW TRIGA-(Training, Research, Isotope Production, General Atomics)-conversion-type reactor at the Idaho National Laboratory; it is primarily used for neutron radiography analysis of irradiated and unirradiated fuels and materials. The NRAD reactor was converted from HEU to LEU fuel with 60 fuel elements and brought critical on March 31, 2010. This configuration of the NRAD reactor has been evaluated as an acceptable benchmark experiment and is available in the 2011 editions of the International Handbook of Evaluated Criticality Safety Benchmark Experiments (ICSBEP Handbook) and the International Handbook of Evaluated Reactor Physics Benchmark Experiments (IRPhEP Handbook). Significant effort went into precisely characterizing all aspects of the reactor core dimensions and material properties; detailed analyses of reactor parameters minimized experimental uncertainties. The largest contributors to the total benchmark uncertainty were the 234U, 236U, Er, and Hf content in the fuel; the manganese content in the stainless steel cladding; and the unknown level of water saturation in the graphite reflector blocks. A simplified benchmark model of the NRAD reactor was prepared with a keff of 1.0012 {+-} 0.0029 (1s). Monte Carlo calculations with MCNP5 and KENO-VI and various neutron cross section libraries were performed and compared with the benchmark eigenvalue for the 60-fuel-element core configuration; all calculated eigenvalues are between 0.3 and 0.8% greater than the benchmark value. Benchmark evaluations of the NRAD reactor are beneficial in understanding biases and uncertainties affecting criticality safety analyses of storage, handling, or transportation applications with LEU-Er-Zr-H fuel.

J. D. Bess; T. L. Maddock; M. A. Marshall

2011-09-01T23:59:59.000Z

336

VHTR Core Shuffling Algorithm Using Particle Swarm Optimization ReloPSO-3D  

E-Print Network (OSTI)

Improving core performance by reshuffling/reloading the fuel blocks within the core is one of the in-core fuel management methods with two major benefits: a possibility to improve core life and increase core safety. VHTR is a hexagonal annular core...

Lakshmipathy, Sathish Kumar

2012-07-16T23:59:59.000Z

337

The microstructure of polar ice. Part I: Highlights from ice core research  

Science Journals Connector (OSTI)

Abstract Polar ice sheets play a fundamental role in Earth's climate system, by interacting actively and passively with the environment. Active interactions include the creeping flow of ice and its effects on polar geomorphology, global sea level, ocean and atmospheric circulation, and so on. Passive interactions are mainly established by the formation of climate records within the ice, in form of air bubbles, dust particles, salt microinclusions and other derivatives of airborne impurities buried by recurrent snowfalls. For a half-century scientists have been drilling deep ice cores in Antarctica and Greenland for studying such records, which can go back to around a million years. Experience shows, however, that the ice-sheet flow generally disrupts the stratigraphy of the bottom part of deep ice cores, destroying the integrity of the oldest records. For all these reasons glaciologists have been studying the microstructure of polar ice cores for decades, in order to understand the genesis and fate of ice-core climate records, as well as to learn more about the physical properties of polar ice, aiming at better climate-record interpretations and ever more precise models of ice-sheet dynamics. In this Part I we review the main difficulties and advances in deep ice core drilling in Antarctica and Greenland, together with the major contributions of deep ice coring to the research on natural ice microstructures. In particular, we discuss in detail the microstructural findings from Camp Century, Byrd, Dye 3, GRIP, GISP2, NorthGRIP, Vostok, Dome C, EDML, and Dome Fuji, besides commenting also on the earlier results of some pioneering ventures, like the Jungfraujoch Expedition and the Norwegian–British–Swedish Antarctic Expedition, among others. In the companion Part II of this work (Faria et al., 2014), the review proceeds with a survey of the state-of-the-art understanding of natural ice microstructures and some exciting prospects in this field of research.

Sérgio H. Faria; Ilka Weikusat; Nobuhiko Azuma

2014-01-01T23:59:59.000Z

338

Beryllium-10 in the Taylor Dome ice core: Applications to Antarctic glaciology and paleoclimatology  

SciTech Connect

An ice core was drilled at Taylor dome, East Antarctica, reaching to bedrock at 554 meters. Oxygen-isotope measurements reveal climatic fluctuations through the last interglacial period. To facilitate comparison of the Taylor Dome paleoclimate record with geologic data and results from other deep ice cores, several glaciological issues need to be addressed. In particular, accumulation data are necessary as input for numerical ice-flow-models, for determining the flux of chemical constituents from measured concentrations, and for calculation of the offset in age between ice and trapped air in the core. The analysis of cosmogenic beryllium-10 provides a geochemical method for constraining the accumulation-rate history at Taylor Dome. High-resolution measurements were made in shallow firn cores and snow pits to determine the relationship among beryllium-10 concentrations, wet and dry deposition mechanisms, and snow-accumulation rates. Comparison between theoretical and measured variations in deposition over the last 75 years constrains the relationship between beryllium-10 deposition and global average production rates. The results indicate that variations in geomagnetically-modulated production-rate do not strongly influence beryllium-10 deposition at Taylor Dome. Although solar modulation of production rate is important for time scales of years to centuries, snow-accumulation rate is the dominant control on ice-core beryllium-10 concentrations for longer periods. Results show that the Taylor Dome core can be used to provide new constraints on regional climate over the last 130,000 years, complementing the terrestrial and marine geological record from the Dry Valley, Transantarctic Mountains and western Ross Sea.

Steig, E.J.

1996-12-31T23:59:59.000Z

339

AMD Core Math Library (ACML) at NERSC  

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

ACML ACML ACML Description The AMD Core Math Library (ACML) module is available on Hopper but is no longer loaded as part of the default PrgEnv environment. Instead, BLAS and LAPACK functionality is now provided by Cray LibSci. However, if you need ACML for FFT functions, math functions, or random number generators, you can load the library using the acml modulefile. ACML includes: A suite of Fast Fourier Transform (FFT) routines for real and complex data Fast scalar, vector, and array math transcendental library routines optimized for high performance A comprehensive random number generator suite: Base generators plus a user-defined generator Distribution generators Multiple-stream support ACML's internal timing facility uses the clock() function. If you run an

340

From New York to California, SECA's Core  

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

From New York to California, SECA's Core Technology Program is working on dozens of fuel cell projects, led by the brightest minds from leading universities, national laboratories and businesses across the country. These competitively selected projects work together to provide vital R&D and testing support to the six Industry Teams. SECA R&D: Where Competition Meets Collaboration SECA R&D: Where Competition Meets Collaboration SECA Cost Reduction: The Power of a Goal SECA Cost Reduction: The Power of a Goal The SECA program's Industry Teams are hard at work on the design and manufacture of a variety of low-cost fuel cell prototypes. Recent testing of these prototypes has demonstrated giant leaps made toward fuel cell commercialization.

Note: This page contains sample records for the topic "larger core models" 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

Geologic analysis of Devonian Shale cores  

SciTech Connect

Cleveland Cliffs Iron Company was awarded a DOE contract in December 1977 for field retrieval and laboratory analysis of cores from the Devonian shales of the following eleven states: Michigan, Illinois, Indiana, Ohio, New York, Pennsylvania, West Virginia, Maryland, Kentucky, Tennessee and Virginia. The purpose of this project is to explore these areas to determine the amount of natural gas being produced from the Devonian shales. The physical properties testing of the rock specimens were performed under subcontract at Michigan Technological University (MTU). The study also included LANDSAT information, geochemical research, structural sedimentary and tectonic data. Following the introduction, and background of the project this report covers the following: field retrieval procedures; laboratory procedures; geologic analysis (by state); references and appendices. (ATT)

none,

1982-02-01T23:59:59.000Z

342

Rotary Mode Core Sample System availability improvement  

SciTech Connect

The Rotary Mode Core Sample System (RMCSS) is used to obtain stratified samples of the waste deposits in single-shell and double-shell waste tanks at the Hanford Site. The samples are used to characterize the waste in support of ongoing and future waste remediation efforts. Four sampling trucks have been developed to obtain these samples. Truck I was the first in operation and is currently being used to obtain samples where the push mode is appropriate (i.e., no rotation of drill). Truck 2 is similar to truck 1, except for added safety features, and is in operation to obtain samples using either a push mode or rotary drill mode. Trucks 3 and 4 are now being fabricated to be essentially identical to truck 2.

Jenkins, W.W.; Bennett, K.L.; Potter, J.D. [Westinghouse Hanford Co., Richland, WA (United States); Cross, B.T.; Burkes, J.M.; Rogers, A.C. [Southwest Research Institute (United States)

1995-02-28T23:59:59.000Z

343

Modeling  

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

ALE-AMR ALE-AMR code Wangyi Liu, John Bernard, Alex Friedman, Nathan Masters, Aaron Fisher, Velemir Mlaker, Alice Koniges, David Eder June 4, 2011 Abstract In this paper we describe an implementation of a single-fluid inter- face model in the ALE-AMR code to simulate surface tension effects. The model does not require explicit information on the physical state of the two phases. The only change to the existing fluid equations is an additional term in the stress tensor. We show results of applying the model to an expanding Al droplet surrounded by an Al vapor, where additional droplets are created. 1 Introduction The Neutralized Drift Compression Experiment II (NDCX II) is an induction accelerator planned for initial commissioning in 2012. The final design calls for a 3 MeV, Li+ ion beam, delivered in a bunch with characteristic pulse duration of 1 ns, and transverse dimension of order 1 mm. The

344

CORRELATING INFALL WITH DEUTERIUM FRACTIONATION IN DENSE CORES  

SciTech Connect

We present a survey of HCO{sup +} (3-2) observations pointed toward dense cores with previous measurements of N(N{sub 2}D{sup +})/N(N{sub 2}H{sup +}). Of the 26 cores in this survey, 5 show the spectroscopic signature of outward motion, 9 exhibit neither inward nor outward motion, 11 appear to be infalling, and 1 is not detected. We compare the degree of deuterium fractionation with infall velocities calculated from the HCO{sup +} spectra and find that those cores with [D]/[H] > 0.1 are more likely to have the signature of inward motions than cores with smaller [D]/[H] ratios. Infall motions are also much more common in cores with masses exceeding their thermal Jeans masses. The fastest infall velocity measured belongs to one of the two protostellar cores in our survey, L1521F, and the observed motions are typically on the order of the sound speed.

Schnee, Scott; Brunetti, Nathan; Friesen, Rachel [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Di Francesco, James; Johnstone, Doug; Pon, Andy [National Research Council Canada, Herzberg Institute of Astrophysics, 5071 West Saanich Road Victoria, BC V9E 2E7 (Canada); Caselli, Paola, E-mail: sschnee@nrao.edu [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom)

2013-11-10T23:59:59.000Z

345

Turbine component casting core with high resolution region  

DOE Patents (OSTI)

A hollow turbine engine component with complex internal features can include a first region and a second, high resolution region. The first region can be defined by a first ceramic core piece formed by any conventional process, such as by injection molding or transfer molding. The second region can be defined by a second ceramic core piece formed separately by a method effective to produce high resolution features, such as tomo lithographic molding. The first core piece and the second core piece can be joined by interlocking engagement that once subjected to an intermediate thermal heat treatment process thermally deform to form a three dimensional interlocking joint between the first and second core pieces by allowing thermal creep to irreversibly interlock the first and second core pieces together such that the joint becomes physically locked together providing joint stability through thermal processing.

Kamel, Ahmed; Merrill, Gary B.

2014-08-26T23:59:59.000Z

346

High School Students' Modeling Knowledge High School Students' Modeling Knowledge  

E-Print Network (OSTI)

High School Students' Modeling Knowledge High School Students' Modeling Knowledge David Fortus of the authors. #12;High School Students' Modeling Knowledge Abstract Modeling is a core scientific practice. This study probed the modeling knowledge of high school students who had not any explicit exposure

347

Self-mixing phenomenology in hypothetical core-disruptive accidents  

SciTech Connect

Physical processes are investigated that lead to the thermal equilibration of a disrupted liquid metal fast breeder reactor (LMFBR) core following a hypothetical core-disruptive accident (HCDA). Their impact is assessed, particularly as relating to the SIMMER code. The turbulent structure in the core region is characterized and bounding estimates are derived of thermal equilibration (''self-mixing'') times. The implication of these results for LMFBR safety research is discussed briefly.

Chapyak, E.J.

1980-12-01T23:59:59.000Z

348

MIC-SVM: Designing A Highly Efficient Support Vector Machine For Advanced Modern Multi-Core and Many-Core Architectures  

SciTech Connect

Support Vector Machine (SVM) has been widely used in data-mining and Big Data applications as modern commercial databases start to attach an increasing importance to the analytic capabilities. In recent years, SVM was adapted to the ?eld of High Performance Computing for power/performance prediction, auto-tuning, and runtime scheduling. However, even at the risk of losing prediction accuracy due to insuf?cient runtime information, researchers can only afford to apply of?ine model training to avoid signi?cant runtime training overhead. To address the challenges above, we designed and implemented MICSVM, a highly efficient parallel SVM for x86 based multi-core and many core architectures, such as the Intel Ivy Bridge CPUs and Intel Xeon Phi coprocessor (MIC).

You, Yang; Song, Shuaiwen; Fu, Haohuan; Marquez, Andres; Mehri Dehanavi, Maryam; Barker, Kevin J.; Cameron, Kirk; Randles, Amanda; Yang, Guangwen

2014-08-16T23:59:59.000Z

349

Rapid Characterization of Drill Core and Cutting Mineralogy using Infrared  

Open Energy Info (EERE)

Rapid Characterization of Drill Core and Cutting Mineralogy using Infrared Rapid Characterization of Drill Core and Cutting Mineralogy using Infrared Spectroscopy Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Rapid Characterization of Drill Core and Cutting Mineralogy using Infrared Spectroscopy Abstract Infrared spectroscopy is particularly good at identifying awide variety of hydrothermally altered minerals with no samplepreparation, and is especially helpful in discrimination amongclay minerals. We have performed several promising pilot studieson geothermal drill core and cuttings that suggest the efficiencyof the technique to sample continuously and provide alterationlogs similar to geophysical logs. We have successfully identifiedlayered silicates, zeolites, opal, calcite, and iron oxides and

350

Methanesulfonate in the Greenland Ice Sheet Project 2 Ice Core  

E-Print Network (OSTI)

sulfate in the Dye 3 and Camp Century Greenland ice cores infor SO4 2- in the Dye 3, Camp Century, MSA to non-sea salt

Saltzman, E. S; Whung, P.-Y.; Mayewski, P. A

1997-01-01T23:59:59.000Z

351

Core Analysis At Mcgee Mountain Area (DOE GTP) | Open Energy...  

Open Energy Info (EERE)

Mcgee Mountain Area Exploration Technique Core Analysis Activity Date Usefulness not indicated DOE-funding Unknown References (1 January 2011) GTP ARRA Spreadsheet Additional...

352

Core Analysis At Valles Caldera - Sulphur Springs Geothermal...  

Open Energy Info (EERE)

Details Location Valles Caldera - Sulphur Springs Geothermal Area Exploration Technique Core Analysis Activity Date - 1992 Usefulness not indicated DOE-funding Unknown Notes...

353

Core Analysis At Jemez Mountain Area (Eichelberger & Koch, 1979...  

Open Energy Info (EERE)

1979) Exploration Activity Details Location Jemez Mountain Area Exploration Technique Core Analysis Activity Date Usefulness useful DOE-funding Unknown References John C....

354

Core Analysis At Colrado Area (DOE GTP) | Open Energy Information  

Open Energy Info (EERE)

GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Analysis At Colrado Area (DOE GTP) Exploration Activity Details Location Colado...

355

Core Holes At Blue Mountain Geothermal Area (Fairbank & Niggemann...  

Open Energy Info (EERE)

Exploration Activity Details Location Blue Mountain Geothermal Area Exploration Technique Core Holes Activity Date 2002 - 2004 Usefulness useful DOE-funding Unknown Exploration...

356

Core Analysis At Long Valley Caldera Geothermal Area (Pribnow...  

Open Energy Info (EERE)

Activity Details Location Long Valley Caldera Geothermal Area Exploration Technique Core Analysis Activity Date - 2003 Usefulness useful DOE-funding Unknown Notes "Here we...

357

Core Analysis At Alum Area (DOE GTP) | Open Energy Information  

Open Energy Info (EERE)

GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Analysis At Alum Area (DOE GTP) Exploration Activity Details Location Alum Geothermal...

358

Core Analysis At Fenton Hill HDR Geothermal Area (Brookins &...  

Open Energy Info (EERE)

Activity Details Location Fenton Hill HDR Geothermal Area Exploration Technique Core Analysis Activity Date - 1983 Usefulness useful DOE-funding Unknown Notes See linked...

359

Annular Core Research Reactor - Critical to Science-Based Weapons...  

National Nuclear Security Administration (NNSA)

Annular Core Research Reactor - Critical to Science-Based Weapons Design, Certification | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People...

360

Percolation Explains How Earth's Iron Core Formed | Stanford...  

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

experimental results have ruled out percolation as a major core formation mechanism for Earth at the relatively lower pressure conditions in the upper mantle, but until now...

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


361

Magnetic Vortex Core Reversal by Low-Field Excitations  

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

Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known...

362

Loading rubidium atoms into a hollow core fiber .  

E-Print Network (OSTI)

??We demonstrate a procedure for cooling, trapping, and transferring rubidium atoms into a hollow core photonic band gap fiber. The atoms are first collected in… (more)

Chu, Yiwen

2007-01-01T23:59:59.000Z

363

Study of Superconducting Fault Current Limiter Using Saturated Magnetic Core  

Science Journals Connector (OSTI)

This paper presents a saturated magnetic core superconducting current limiter (SCSFCL) operation simulation results using finite element technique. The superconducting current limiter uses BSCCO tape to produce m...

F. Fajoni; E. Ruppert; C. A. Baldan…

2014-11-01T23:59:59.000Z

364

Core Holes At Long Valley Caldera Geothermal Area (Eichelberger...  

Open Energy Info (EERE)

Eichelberger, Et Al., 1988) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Holes At Long Valley Caldera Geothermal Area (Eichelberger, Et...

365

Core Holes At Steamboat Springs Area (Warpinski, Et Al., 2004...  

Open Energy Info (EERE)

Steamboat Springs Area (Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Holes At Steamboat Springs Area (Warpinski,...

366

Core Analysis At Yellowstone Region (Dobson, Et Al., 2003) |...  

Open Energy Info (EERE)

Dobson, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Analysis At Yellowstone Region (Dobson, Et Al., 2003) Exploration...

367

Core Holes At Long Valley Caldera Geothermal Area (Urban, Et...  

Open Energy Info (EERE)

Urban, Et Al., 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Holes At Long Valley Caldera Geothermal Area (Urban, Et Al., 1987)...

368

Core Analysis At Newberry Caldera Area (Carothers, Et Al., 1987...  

Open Energy Info (EERE)

Carothers, Et Al., 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Analysis At Newberry Caldera Area (Carothers, Et Al., 1987)...

369

Rollover analysis of rotary mode core sampler truck No. 2  

SciTech Connect

This document provides estimate of limiting speed and rollover analysis of rotary mode core sampler truck No. 2 (RMCST No. 2).

Ziada, H.H.

1994-11-08T23:59:59.000Z

370

Core Analysis At Long Valley Caldera Geothermal Area (Smith ...  

Open Energy Info (EERE)

Smith & Suemnicht, 1991) Exploration Activity Details Location Long Valley Caldera Geothermal Area Exploration Technique Core Analysis Activity Date 1985 - 1988 Usefulness useful...

371

Core Holes At Valles Caldera - Redondo Geothermal Area (Goff...  

Open Energy Info (EERE)

understand the stratigraphy, structure, hydrothermal alteration, and subsurface architecture of the Valles caldera. Several authors have reported results from these core holes,...

372

Core Holes At Valles Caldera - Sulphur Springs Geothermal Area...  

Open Energy Info (EERE)

understand the stratigraphy, structure, hydrothermal alteration, and subsurface architecture of the Valles caldera. Several authors have reported results from these core holes,...

373

Multi-model Mean Nitrogen and Sulfur Deposition from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): Evaluation of Historical and Projected Future Changes  

SciTech Connect

We present multi-model global datasets of nitrogen and sulfate deposition covering time periods from 1850 to 2100, calculated within the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP). The computed deposition fluxes are compared to surface wet deposition and ice-core measurements. We use a new dataset of wet deposition for 2000-2002 based on critical assessment of the quality of existing regional network data. We show that for present-day (year 2000 ACCMIP time-slice), the ACCMIP results perform similarly to previously published multi-model assessments. The analysis of changes between 1980 and 2000 indicates significant differences between model and measurements over the United States, but less so over Europe. This difference points towards misrepresentation of 1980 NH3 emissions over North America. Based on ice-core records, the 1850 deposition fluxes agree well with Greenland ice cores but the change between 1850 and 2000 seems to be overestimated in the Northern Hemisphere for both nitrogen and sulfur species. Using the Representative Concentration Pathways to define the projected climate and atmospheric chemistry related emissions and concentrations, we find large regional nitrogen deposition increases in 2100 in Latin America, Africa and parts of Asia under some of the scenarios considered. Increases in South Asia are especially large, and are seen in all scenarios, with 2100 values more than double 2000 in some scenarios and reaching >1300 mgN/m2/yr averaged over regional to continental scale regions in RCP 2.6 and 8.5, ~30-50% larger than the values in any region currently (2000). Despite known issues, the new ACCMIP deposition dataset provides novel, consistent and evaluated global gridded deposition fields for use in a wide range of climate and ecological studies.

Lamarque, Jean-Francois; Dentener, Frank; McConnell, J.R.; Ro, C-U; Shaw, Mark; Vet, Robert; Bergmann, D.; Cameron-Smith, Philip; Dalsoren, S.; Doherty, R.; Faluvegi, G.; Ghan, Steven J.; Josse, B.; Lee, Y. H.; MacKenzie, I. A.; Plummer, David; Shindell, Drew; Skeie, R. B.; Stevenson, D. S.; Strode, S.; Zeng, G.; Curran, M.; Dahl-Jensen, D.; Das, S.; Fritzsche, D.; Nolan, M.

2013-08-20T23:59:59.000Z

374

Assessment of RELAP5/MOD3.1 for gravity-driven injection experiment in the core makeup tank of the CARR Passive Reactor (CP-1300)  

SciTech Connect

The objective of the present work is to improve the analysis capability of RELAP5/MOD3.1 on the direct contact condensation in the core makeup tank (CMT) of passive high-pressure injection system (PHPIS) in the CARR Passive Reactor (CP-1300). The gravity-driven injection experiment is conducted by using a small scale test facility to identify the parameters having significant effects on the gravity-driven injection and the major condensation modes. It turns out that the larger the water subcooling is, the more initiation of injection is delayed, and the sparger and the natural circulation of the hot water from the steam generator accelerate the gravity-driven injection. The condensation modes are divided into three modes: sonic jet, subsonic jet, and steam cavity. RELAP5/MOD3.1 is chosen to evaluate the cod predictability on the direct contact condensation in the CMT. It is found that the predictions of MOD3.1 are in better agreement with the experimental data than those of MOD3.0. From the nodalization study of the test section, the 1-node model shows better agreement with the experimental data than the multi-node models. RELAP5/MOD3.1 identifies the flow regime of the test section as vertical stratification. However, the flow regime observed in the experiment is the subsonic jet with the bubble having the vertical cone shape. To accurately predict the direct contact condensation in the CMT with RELAP5/MOD3.1, it is essential that a new set of the interfacial heat transfer coefficients and a new flow regime map for direct contact condensation in the CMT be developed.

Lee, S.I.; No, H.C. [Korea Advanced Inst. of Science and Technology, Yusung, Taejon (Korea, Republic of). Nuclear Engineering Dept.; Bang, Y.S.; Kim, H.J. [Korea Inst. of Nuclear Safety, Yusung Taejon (Korea, Republic of). Advanced Reactor Dept.

1996-10-01T23:59:59.000Z

375

How does torsional rigidity affect the wrapping transition of a semiflexible chain around a spherical core?  

E-Print Network (OSTI)

We investigated the effect of torsional rigidity of a semiflexible chain on the wrapping transition around a spherical core, as a model of nucleosome, the fundamental unit of chromatin. Through molecular dynamics simulation, we show that the torsional effect has a crucial effect on the chain wrapping around the core under the topological constraints. In particular, the torsional stress (i) induces the wrapping/unwrapping transition, and (ii) leads to a unique complex structure with an antagonistic wrapping direction which never appears without the topological constraints. We further examine the effect of the stretching stress for the nucleosome model, in relation to the unique characteristic effect of the torsional stress on the manner of wrapping.

Yuji Higuchi; Takahiro Sakaue; Kenichi Yoshikawa

2010-04-22T23:59:59.000Z

376

Calculation of the reactivity feedback due to core-assembly bowing in LMFBRs  

SciTech Connect

The nonuniformity of the temperature distribution in an LMFBR leads to differential thermal expansion of the walls of an assembly hexcan. These thermal expansion differentials cause the hexcan to distort or bow. Consequentially, the assembly experiences a spatial displacement, which results in a change in reactivity for the core. A computational model to calculate the reactivity feedback due to material displacements induced by assembly bowing effects has been developed.

Not Available

1983-01-01T23:59:59.000Z

377

Advanced Core Design And Fuel Management For Pebble-Bed Reactors  

SciTech Connect

A method for designing and optimizing recirculating pebble-bed reactor cores is presented. At the heart of the method is a new reactor physics computer code, PEBBED, which accurately and efficiently computes the neutronic and material properties of the asymptotic (equilibrium) fuel cycle. This core state is shown to be unique for a given core geometry, power level, discharge burnup, and fuel circulation policy. Fuel circulation in the pebble-bed can be described in terms of a few well?defined parameters and expressed as a recirculation matrix. The implementation of a few heat?transfer relations suitable for high-temperature gas-cooled reactors allows for the rapid estimation of thermal properties critical for safe operation. Thus, modeling and design optimization of a given pebble-bed core can be performed quickly and efficiently via the manipulation of a limited number key parameters. Automation of the optimization process is achieved by manipulation of these parameters using a genetic algorithm. The end result is an economical, passively safe, proliferation-resistant nuclear power plant.

Hans D. Gougar; Abderrafi M. Ougouag; William K. Terry

2004-10-01T23:59:59.000Z

378

CO2 flood tests on whole core samples of the Mt. Simon sandstone, Illinois Basin  

SciTech Connect

Geological sequestration of CO2, whether by enhanced oil recovery (EOR), coal-bed methane (CBM) recovery, or saline aquifer injection is a promising near-term sequestration methodology. While tremendous experience exists for EOR, and CBM recovery has been demonstrated in existing fields, saline aquifer injection studies have only recently been initiated. Studies evaluating the availability of saline aquifers suitable for CO2 injection show great potential, however, the long-term fate of the CO2 injected into these ancient aqueous systems is still uncertain. For the subject study, a series of laboratory-scale CO2 flood tests were conducted on whole core samples of the Mt. Simon sandstone from the Illinois Basin. By conducting these tests on whole core samples rather than crushed core, an evaluation of the impact of the CO2 flood on the rock mechanics properties as well as the geochemistry of the core and brine solution has been possible. This empirical data could provide a valuable resource for the validation of reservoir models under development for these engineered CO2 systems.

O'Connor, William K.; Rush, Gilbert E.

2005-09-01T23:59:59.000Z

379

MORECA: A computer code for simulating modular high-temperature gas-cooled reactor core heatup accidents  

SciTech Connect

The design features of the modular high-temperature gas-cooled reactor (MHTGR) have the potential to make it essentially invulnerable to damage from postulated core heatup accidents. This report describes the ORNL MORECA code, which was developed for analyzing postulated long-term core heatup scenarios for which active cooling systems used to remove afterheat following the accidents can be assumed to the unavailable. Simulations of long-term loss-of-forced-convection accidents, both with and without depressurization of the primary coolant, have shown that maximum core temperatures stay below the point at which any significant fuel failures and fission product releases are expected. Sensitivity studies also have been done to determine the effects of errors in the predictions due both to uncertainties in the modeling and to the assumptions about operational parameters. MORECA models the US Department of Energy reference design of a standard MHTGR.

Ball, S.J. (Oak Ridge National Lab., TN (United States))

1991-10-01T23:59:59.000Z

380

Increasing pipelined IP core utilization in Process Networks using Exploration  

E-Print Network (OSTI)

Increasing pipelined IP core utilization in Process Networks using Exploration Claudiu Zissulescu pipelined. In this paper, we present an exploration methodology that uses feedback provided by the Laura tool to increase the uti- lization of IP cores embedded in our PN network. Using this exploration, we

Kienhuis, Bart

Note: This page contains sample records for the topic "larger core models" 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

THE PHYSICS OF CORE COLLAPSE Eliza McDonald  

E-Print Network (OSTI)

of two main types of supernova Caused as stars collapse in on themselves as fusion stops Leaves behind M Star #12;CORE COLLAPSE Fusion stops after Iron, leaving an inert core After Chandrasekhar mass 2005 #12;CONCLUSIONS Stars are held up by pressure from nuclear fusion, and fall in when that fusion

Budker, Dmitry

382

Core-level Spectroscopies with FEFF9 and OCEAN  

E-Print Network (OSTI)

Core-level Spectroscopies with FEFF9 and OCEAN J. J. Rehr1,4 K. Gilmore,2,4 J. Kas,1 J. Vinson,3 E European Theoretical Spectroscopy Facility Supported by DOE BES Soleil Theory Day Synchrotron SOLEIL, Grand Amphi 6/5/2014 #12;Core-level Spectroscopies with FEFF9 and OCEAN · GOAL: ab initio theory · Accuracy

Botti, Silvana

383

Using Dublin Core application profiles to manage diverse metadata developments  

Science Journals Connector (OSTI)

This paper discusses the use of Dublin Core application profiles at the British Library as part of a resource discovery strategy. It shows how they can be used to control the proliferation of metadata formats in digitisation activity and provide interoperability ... Keywords: British library, Dublin Core application profiles, SRU, Z39.50, gateway, interoperability, metadata formats, resource discovery strategy

Robina Clayphan; Bill Oldroyd

2005-09-01T23:59:59.000Z

384

New insights on the solar core  

E-Print Network (OSTI)

Since the detection of the asymptotic properties of the dipole gravity modes in the Sun, the quest to find individual gravity modes has continued. An extensive and deeper analysis of 14 years of continuous GOLF/SoHO observational data, unveils the presence of a pattern of peaks that could be interpreted as individual dipole gravity modes in the frequency range between 60 and 140 microHz, with amplitudes compatible with the latest theoretical predictions. By collapsing the power spectrum we have obtained a quite constant splitting for these patterns in comparison to regions where no g modes were expected. Moreover, the same technique applied to simultaneous VIRGO/SoHO data unveils some common signals between the power spectra of both instruments. Thus, we are able to identify and characterize individual g modes with their central frequencies, amplitudes and splittings allowing to do seismic inversions of the rotation profile inside the solar core. These results open a new light on the physics and dynamics of t...

Garcia, R A; Ballot, J; Eff-Darwich, A; Garrido, R; Jimenez, A; Mathis, S; Mathur, S; Moya, A; Palle, P L; Regulo, C; Sato, K; Suarez, J C; Turck-Chieze, S

2010-01-01T23:59:59.000Z

385

Formation of a flux core spheromak  

Science Journals Connector (OSTI)

An alternate design for compact tori specifically of the spheromak type is studied. In this design the ‘‘flux core spheromak’’ [Nucl. Fusion 29 219 (1989)] the externally imposed bias field links the confinement region of closed flux surfaces. The advantages of this configuration are: (i) it enjoys greater stability to magnetohydrodynamic (MHD) modes particularly the tilt and shift; (ii) it has a poloidal divertor and an amount of poloidal flux separating the closed flux surface region from the walls; and (iii) it might be sustained by helicity injection. Results are presented showing the dependence of the geometry on the distribution of bias flux on the conducting walls and showing the optimization of the 2?D formation scheme to minimize the contact of the plasma with coils electrodes and walls. This last topic involves taking advantage of current sheet formation and subsequent tearing as in formation of the MS spheromak [Phys. Fluids 28 3154 (1985)]. The parameters which can be varied to produce this favorable formation scheme via tearing rather than a formation that proceeds off the reversal coils are explored. In addition it is found that there is strong viscous heating of the ions in this early reconnection phase.

John M. Finn; Parvez N. Guzdar

1991-01-01T23:59:59.000Z

386

Solid oxide fuel cell with monolithic core  

DOE Patents (OSTI)

A solid oxide fuel cell in which fuel and oxidant gases undergo an electrochemical reaction to produce an electrical output includes a monolithic core comprised of a corrugated conductive sheet disposed between upper and lower generally flat sheets. The corrugated sheet includes a plurality of spaced, parallel, elongated slots which form a series of closed, linear, first upper and second lower gas flow channels with the upper and lower sheets within which a fuel gas and an oxidant gas respectively flow. Facing ends of the fuel cell are generally V-shaped and provide for fuel and oxidant gas inlet and outlet flow, respectively, and include inlet and outlet gas flow channels which are continuous with the aforementioned upper fuel gas and lower oxidant gas flow channels. The upper and lower flat sheets and the intermediate corrugated sheet are preferably comprised of ceramic materials and are securely coupled together such as by assembly in the green state and sintering together during firing at high temperatures. A potential difference across the fuel cell, or across a stacked array of similar fuel cells, is generated when an oxidant gas such as air and a fuel such as hydrogen gas is directed through the fuel cell at high temperatures, e.g., between 700 C and 1,100 C. 8 figs.

McPheeters, C.C.; Mrazek, F.C.

1988-08-02T23:59:59.000Z

387

Solid oxide fuel cell with monolithic core  

DOE Patents (OSTI)

A solid oxide fuel cell in which fuel and oxidant gases undergo an electrochemical reaction to produce an electrical output includes a monolithic core comprised of a corrugated conductive sheet disposed between upper and lower generally flat sheets. The corrugated sheet includes a plurality of spaced, parallel, elongated slots which form a series of closed, linear, first upper and second lower gas flow channels with the upper and lower sheets within which a fuel gas and an oxidant gas respectively flow. Facing ends of the fuel cell are generally V-shaped and provide for fuel and oxidant gas inlet and outlet flow, respectively, and include inlet and outlet gas flow channels which are continuous with the aforementioned upper fuel gas and lower oxidant gas flow channels. The upper and lower flat sheets and the intermediate corrugated sheet are preferably comprised of ceramic materials and are securely coupled together such as by assembly in the green state and sintering together during firing at high temperatures. A potential difference across the fuel cell, or across a stacked array of similar fuel cells, is generated when an oxidant gas such as air and a fuel such as hydrogen gas is directed through the fuel cell at high temperatures, e.g., between 700.degree. C. and 1100.degree. C.

McPheeters, Charles C. (Plainfield, IL); Mrazek, Franklin C. (Hickory Hills, IL)

1988-01-01T23:59:59.000Z

388

DOE Regional Partnership Begins Core Sampling for Large-Volume  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Regional Partnership Begins Core Sampling for Large-Volume Regional Partnership Begins Core Sampling for Large-Volume Sequestration Test DOE Regional Partnership Begins Core Sampling for Large-Volume Sequestration Test May 22, 2009 - 1:00pm Addthis Washington, DC - The Plains CO2 Reduction (PCOR) Partnership, one of seven members of the U.S. Department of Energy's Regional Carbon Sequestration Partnerships program, has begun collecting core samples from a new characterization well near Spectra Energy's Fort Nelson natural gas processing plant in British Columbia, Canada. Core sampling, along with a sophisticated well logging program that the partnership is conducting, is an important step in proving the viability of carbon storage in brine-saturated formations. The Fort Nelson project is on track to become one of the first

389

Core Technology Ventures Services CTV | Open Energy Information  

Open Energy Info (EERE)

Technology Ventures Services CTV Technology Ventures Services CTV Jump to: navigation, search Name Core Technology Ventures Services (CTV) Place Co Durham, United Kingdom Zip DL13 3DS Sector Hydro, Hydrogen Product An independent advisory team focused on seed and early stage companies developing fuel cell systems and hydrogen storage technologies. References Core Technology Ventures Services (CTV)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Core Technology Ventures Services (CTV) is a company located in Co Durham, United Kingdom . References ↑ "Core Technology Ventures Services (CTV)" Retrieved from "http://en.openei.org/w/index.php?title=Core_Technology_Ventures_Services_CTV&oldid=34391

390

DOE Regional Partnership Begins Core Sampling for Large-Volume  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Regional Partnership Begins Core Sampling for Large-Volume Regional Partnership Begins Core Sampling for Large-Volume Sequestration Test DOE Regional Partnership Begins Core Sampling for Large-Volume Sequestration Test May 22, 2009 - 1:00pm Addthis Washington, DC - The Plains CO2 Reduction (PCOR) Partnership, one of seven members of the U.S. Department of Energy's Regional Carbon Sequestration Partnerships program, has begun collecting core samples from a new characterization well near Spectra Energy's Fort Nelson natural gas processing plant in British Columbia, Canada. Core sampling, along with a sophisticated well logging program that the partnership is conducting, is an important step in proving the viability of carbon storage in brine-saturated formations. The Fort Nelson project is on track to become one of the first

391

Core Analysis At Valles Caldera - Sulphur Springs Area (Woldegabriel &  

Open Energy Info (EERE)

Woldegabriel & Woldegabriel & Goff, 1992) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Analysis At Valles Caldera - Sulphur Springs Area (Woldegabriel & Goff, 1992) Exploration Activity Details Location Valles Caldera - Sulphur Springs Area Exploration Technique Core Analysis Activity Date Usefulness not indicated DOE-funding Unknown Notes Samples for age dating taken from core hole VC-2B in the Suphur Springs area of the Valles Caldera. References Giday WoldeGabriel, Fraser Goff (1992) K-Ar Dates Of Hydrothermal Clays From Core Hole Vc-2B, Valles Caldera, New Mexico And Their Relation To Alteration In A Large Hydrothermal System Retrieved from "http://en.openei.org/w/index.php?title=Core_Analysis_At_Valles_Caldera_-_Sulphur_Springs_Area_(Woldegabriel_%26_Goff,_1992)&oldid=387687"

392

Process to make core-shell structured nanoparticles  

DOE Patents (OSTI)

Disclosed is a process for making a composite material that contains core-shell structured nanoparticles. The process includes providing a precursor in the form of a powder a liquid and/or a vapor of a liquid that contains a core material and a shell material, and suspending the precursor in an aerosol gas to produce an aerosol containing the precursor. In addition, the process includes providing a plasma that has a hot zone and passing the aerosol through the hot zone of the plasma. As the aerosol passes through the hot zone of the plasma, at least part of the core material and at least part of the shell material in the aerosol is vaporized. Vapor that contains the core material and the shell material that has been vaporized is removed from the hot zone of the plasma and allowed to condense into core-shell structured nanoparticles.

Luhrs, Claudia; Phillips, Jonathan; Richard, Monique N

2014-01-07T23:59:59.000Z

393

Core Vessel Insert Handling Robot for the Spallation Neutron Source  

SciTech Connect

The Spallation Neutron Source provides the world's most intense pulsed neutron beams for scientific research and industrial development. Its eighteen neutron beam lines will eventually support up to twenty-four simultaneous experiments. Each beam line consists of various optical components which guide the neutrons to a particular instrument. The optical components nearest the neutron moderators are the core vessel inserts. Located approximately 9 m below the high bay floor, these inserts are bolted to the core vessel chamber and are part of the vacuum boundary. They are in a highly radioactive environment and must periodically be replaced. During initial SNS construction, four of the beam lines received Core Vessel Insert plugs rather than functional inserts. Remote replacement of the first Core Vessel Insert plug was recently completed using several pieces of custom-designed tooling, including a highly complicated Core Vessel Insert Robot. The design of this tool are discussed.

Graves, Van B [ORNL; Dayton, Michael J [ORNL

2011-01-01T23:59:59.000Z

394

Theoretical surface core-level shifts for Be(0001)  

SciTech Connect

Core-ionization potentials (CIP's) are computed for Be(0001). Three core features are observed in corresponding photoelectron spectra, with CIP's shifted relative to the bulk core level by [minus]0.825, [minus]0.570, and [minus]0.265 eV. The computed CIP shifts for the outer and subsurface layers, [minus]0.60 and [minus]0.29 eV, respectively, agree with the latter two of these. It is surmised that the [minus]0.825-eV shift is associated with a surface defect. The negative signs of the Be(0001) surface core-level shifts do not fit into the thermochemical picture widely used to explain CIP shifts. The reason is that a core-ionized Be atom is too small to bond effectively to the remainder of the unrelaxed Be lattice.

Feibelman, P.J. (Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States))

1994-05-15T23:59:59.000Z

395

Core Analysis At Raft River Geothermal Area (1979) | Open Energy  

Open Energy Info (EERE)

9) 9) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Core Analysis Activity Date 1979 Usefulness not indicated DOE-funding Unknown Exploration Basis Permitted the lateral and vertical extrapolation of core and test data and bridged the gap between surface geophysical data and core analyses. Notes 1) Microcracks were observed in core samples. A set of observable characteristics of microcracks were discovered in racks from geothermal regions that appears to be unique and to have considerable potential for exploration for geothermal regions. Both permeability and electrical conductivity were measured for a suite of samples with a range of microcracks characteristics. A partial set of samples were collected to study migration of radioactive elements. 2) Laboratory analyses of cores

396

Creation of a Full-Core HTR Benchmark with the Fort St. Vrain Initial Core and Assessment of Uncertainties in the FSV Fuel Composition and Geometry  

SciTech Connect

Information and measured data from the intial Fort St. Vrain (FSV) high temperature gas reactor core is used to develop a benchmark configuration to validate computational methods for analysis of a full-core, commercial HTR configuration. Large uncertainties in the geometry and composition data for the FSV fuel and core are identified, including: (1) the relative numbers of fuel particles for the four particle types, (2) the distribution of fuel kernel diameters for the four particle types, (3) the Th:U ratio in the initial FSV core, (4) and the buffer thickness for the fissile and fertile particles. Sensitivity studies were performed to assess each of these uncertainties. A number of methods were developed to assist in these studies, including: (1) the automation of MCNP5 input files for FSV using Python scripts, (2) a simple method to verify isotopic loadings in MCNP5 input files, (3) an automated procedure to conduct a coupled MCNP5-RELAP5 analysis for a full-core FSV configuration with thermal-hydraulic feedback, and (4) a methodology for sampling kernel diameters from arbitrary power law and Gaussian PDFs that preserved fuel loading and packing factor constraints. A reference FSV fuel configuration was developed based on having a single diameter kernel for each of the four particle types, preserving known uranium and thorium loadings and packing factor (58%). Three fuel models were developed, based on representing the fuel as a mixture of kernels with two diameters, four diameters, or a continuous range of diameters. The fuel particles were put into a fuel compact using either a lattice-bsed approach or a stochastic packing methodology from RPI, and simulated with MCNP5. The results of the sensitivity studies indicated that the uncertainties in the relative numbers and sizes of fissile and fertile kernels were not important nor were the distributions of kernel diameters within their diameter ranges. The uncertainty in the Th:U ratio in the intial FSV core was found to be important with a crude study. The uncertainty in the TRISO buffer thickness was estimated to be unimportant but the study was not conclusive. FSV fuel compacts and a regular FSV fuel element were analyzed with MCNP5 and compared with predictions using a modified version of HELIOS that is capable of analyzing TRISO fuel configurations. The HELIOS analyses were performed by SSP. The eigenvalue discrepancies between HELIOS and MCNP5 are currently on the order of 1% but these are still being evaluated. Full-core FSV configurations were developed for two initial critical configurations - a cold, clean critical loading and a critical configuration at 70% power. MCNP5 predictions are compared to experimental data and the results are mixed. Analyses were also done for the pulsed neutron experiments that were conducted by GA for the initial FSV core. MCNP5 was used to model these experiments and reasonable agreement with measured results has been observed.

Martin, William R.; Lee, John C.; Alan baxter; Chuck Wemple

2012-03-31T23:59:59.000Z

397

CHARACTERIZATION OF CORE SAMPLE COLLECTED FROM THE SALTSTONE DISPOSAL FACILITY  

SciTech Connect

During the month of September 2008, grout core samples were collected from the Saltstone Disposal Facility, Vault 4, cell E. This grout was placed during processing campaigns in December 2007 from Deliquification, Dissolution and Adjustment Batch 2 salt solution. The 4QCY07 Waste Acceptance Criteria sample collected on 11/16/07 represents the salt solution in the core samples. Core samples were retrieved to initiate the historical database of properties of emplaced Saltstone and to demonstrate the correlation between field collected and laboratory prepared samples. Three samples were collected from three different locations. Samples were collected using a two-inch diameter concrete coring bit. In April 2009, the core samples were removed from the evacuated sample container, inspected, transferred to PVC containers, and backfilled with nitrogen. Samples furthest from the wall were the most intact cylindrically shaped cored samples. The shade of the core samples darkened as the depth of coring increased. Based on the visual inspection, sample 3-3 was selected for all subsequent analysis. The density and porosity of the Vault 4 core sample, 1.90 g/cm{sup 3} and 59.90% respectively, were comparable to values achieved for laboratory prepared samples. X-ray diffraction analysis identified phases consistent with the expectations for hydrated Saltstone. Microscopic analysis revealed morphology features characteristic of cementitious materials with fly ash and calcium silicate hydrate gel. When taken together, the results of the density, porosity, x-ray diffraction analysis and microscopic analysis support the conclusion that the Vault 4, Cell E core sample is representative of the expected waste form.

Cozzi, A.; Duncan, A.

2010-01-28T23:59:59.000Z

398

MAGNETIZATION OF CLOUD CORES AND ENVELOPES AND OTHER OBSERVATIONAL CONSEQUENCES OF RECONNECTION DIFFUSION  

SciTech Connect

Recent observational results for magnetic fields in molecular clouds reviewed by Crutcher seem to be inconsistent with the predictions of the ambipolar diffusion theory of star formation. These include the measured decrease in mass to flux ratio between envelopes and cores, the failure to detect any self-gravitating magnetically subcritical clouds, the determination of the flat probability distribution function (PDF) of the total magnetic field strengths implying that there are many clouds with very weak magnetic fields, and the observed scaling B{proportional_to}{rho}{sup 2/3} that implies gravitational contraction with weak magnetic fields. We consider the problem of magnetic field evolution in turbulent molecular clouds and discuss the process of magnetic field diffusion mediated by magnetic reconnection. For this process that we termed 'reconnection diffusion', we provide a simple physical model and explain that this process is inevitable in view of the present-day understanding of MHD turbulence. We address the issue of the expected magnetization of cores and envelopes in the process of star formation and show that reconnection diffusion provides an efficient removal of magnetic flux that depends only on the properties of MHD turbulence in the core and the envelope. We show that as the amplitude of turbulence as well as the scale of turbulent motions decrease from the envelope to the core of the cloud, the diffusion of the magnetic field is faster in the envelope. As a result, the magnetic flux trapped during the collapse in the envelope is being released faster than the flux trapped in the core, resulting in much weaker fields in envelopes than in cores, as observed. We provide simple semi-analytical model calculations which support this conclusion and qualitatively agree with the observational results. Magnetic reconnection is also consistent with the lack of subcritical self-gravitating clouds, with the observed flat PDF of field strengths, and with the scaling of field strength with density. In addition, we demonstrate that the reconnection diffusion process can account for the empirical Larson relations and list a few other implications of the reconnection diffusion concept. We argue that magnetic reconnection provides a solution to the magnetic flux problem of star formation that agrees better with observations than the long-standing ambipolar diffusion paradigm. Due to the illustrative nature of our simplified model we do not seek quantitative agreement, but discuss the complementary nature of our approach to the three-dimensional MHD numerical simulations.

Lazarian, A. [Astronomy Department, University of Wisconsin, Madison, WI 53706 (United States); Esquivel, A. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, 04510 Mexico D.F. (Mexico); Crutcher, R. [Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 W. Green Street, Urbana, IL 61801 (United States)

2012-10-01T23:59:59.000Z

399

FY13 Annual Progress Report for SECA Core Technology Program  

SciTech Connect

This progress report covers technical work performed during fiscal year 2013 at PNNL under Field Work Proposal (FWP) 40552. The report highlights and documents technical progress in tasks related to advanced cell and stack component materials development and computational design and simulation. Primary areas of emphasis for the materials development work were metallic interconnects and coatings, cathode and anode stability/degradation, glass seals, and advanced testing under realistic stack conditions: Metallic interconnects and coatings • Effects of surface modifications to AISI 441 (prior to application of protective spinel coatings) on oxide scale growth and adhesion were evaluated as a function of temperature and time. Cathode stability/degradation • Effects of cathode air humidity on performance and stability of SOFC cathodes were investigated by testing anode-supported cells as a function of time and temperature. • In-situ high temperature XRD measurements were used to correlate changes in cathode lattice structure and composition with performance of anode-supported button cells. Anode stability/degradation • Effects of high fuel steam content on Ni/YSZ anodes were investigated over a range of time and temperature. • Vapor infiltration and particulate additions were evaluated as a potential means of improving tolerance of Ni/YSZ anodes to sulfur-bearing fuel species. Glass seals • A candidate compliant glass-based seal materials were evaluated in terms of microstructural evolution and seal performance as a function of time and temperature. Stack fixture testing • The SECA CTP stack test fixture was used for intermediate and long-term evaluation of candidate materials and processes. Primary areas of emphasis for the computational modeling work were coarse methodology, degradation of stack components, and electrochemical modeling: Coarse methodology • Improvements were made to both the SOFC-MP and SOFC ROM simulation tools. Degradation of stack components • Thermo-mechanical modeling and validation experiments were performed to understand/mitigate degradation of interconnects and seals during long-term stack operation. Electrochemical modeling 4 • Modeling tools were developed to improve understanding of electrochemical performance degradation of SOFCs related to changes in electrode microstructure and chemical interactions with contaminants. During FY13, PNNL continued to work with NETL to increase the extent of interaction between the SECA Core Technology Program and the SECA Industry Teams. In addition to using established mechanisms of communication, such as the annual SECA Workshop, representatives from PNNL and NETL participated in telecons and/or face-to-face meetings with all three industry teams during FY13. During these meetings, PNNL’s Core Technology Program work was presented in detail, after which feedback was solicited regarding current and future research topics. Results of PNNL’s SECA CTP work were also distributed via topical reports for the industry teams, DOE reports, technical society presentations, and papers in peer-reviewed technical journals. 5

Stevenson, Jeffry W.; Koeppel, Brian J.

2014-01-31T23:59:59.000Z

400

An In-Core Power Deposition and Fuel Thermal Environmental Monitor for Long-Lived Reactor Cores  

SciTech Connect

The primary objective of this program is to develop the Constant Temperature Power Sensor (CTPS) as in-core instrumentation that will provide a detailed map of local nuclear power deposition and coolant thermal-hydraulic conditions during the entire life of the core.

Don W. Miller

2004-09-28T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

To improve the lifetime performance of a multicore chip with simple cores, we propose the Core Cannibalization Architec-  

E-Print Network (OSTI)

- ence of hard faults, the CCs can be cannibalized for spare parts at the granularity of pipeline stages that distinguish the issue of self-repair from the case for sin- gle-core processors. First, power and thermal leveraged by superscalar cores to provide self-repair [3, 17, 22]. Just one hard fault in the lone ALU

Sorin, Daniel J.

402

Every BCG with a Strong Radio Agn has an X-Ray Cool Core: Is the Cool Core-Noncool Core Dichotomy Too Simple?  

Science Journals Connector (OSTI)

The radio active galactic nucleus (AGN) feedback in X-ray cool cores has been proposed as a crucial ingredient in the evolution of baryonic structures. However, it has long been known that strong radio AGNs also exist in "noncool core" clusters, which brings up the question whether an X-ray cool core is always required for the radio feedback. In this work, we present a systematic analysis of brightest cluster galaxies (BCGs) and strong radio AGNs in 152 groups and clusters from the Chandra archive. All 69 BCGs with radio AGN more luminous than 2 ? 1023 W Hz–1 at 1.4 GHz are found to have X-ray cool cores. BCG cool cores can be divided into two classes: the large cool core (LCC) class and the corona class. Small coronae, easily overlooked at z > 0.1, can trigger strong heating episodes in groups and clusters, long before LCCs are formed. Strong radio outbursts triggered by coronae may destroy embryonic LCCs and thus provide another mechanism to prevent the formation of LCCs. However, it is unclear whether coronae are decoupled from the radio feedback cycles as they have to be largely immune to strong radio outbursts. Our sample study also shows the absence of groups with a luminous cool core while hosting a strong radio AGN, which is not observed in clusters. This points to a greater impact of radio heating on low-mass systems than clusters. Few L 1.4 GHz > 1024 W Hz–1 radio AGNs (~16%) host an L 0.5-10 keV > 1042 erg s–1 X-ray AGN, while above these thresholds, all X-ray AGNs in BCGs are also radio AGNs. As examples of the corona class, we also present detailed analyses of a BCG corona associated with a strong radio AGN (ESO 137-006 in A3627) and one of the faintest coronae known (NGC 4709 in the Centaurus cluster). Our results suggest that the traditional cool core/noncool core dichotomy is too simple. A better alternative is the cool core distribution function, with the enclosed X-ray luminosity or gas mass.

M. Sun

2009-01-01T23:59:59.000Z

403

Development of a multicell methodology to account for heterogeneous core effects in the core-analysis diffusion code  

SciTech Connect

In CANDU R reactor calculations, the lattice-cell cross sections are calculated with WIMS-AECL, and the three-dimensional core neutron-flux and power distributions are calculated with RFSP-IST. The lattice-cell cross sections employed in RFSP-IST and in many other commercial core-analysis diffusion codes are usually based on the use of single-lattice-cell calculations, without considering the effects of the environment. This approximation is not sufficiently accurate for heterogeneous core configurations in the ACR-1000{sup TM}. A multicell correction method is therefore developed in RFSP-IST to account for heterogeneous core effects in the design and analysis of ACR-1000. The calculation results show that the multicell methodology developed in RFSP-IST is effective, generic, and it works well for ACR core analysis. (authors)

Shen, W. [Atomic Energy of Canada Limited, 2251 Speakman Drive, Mississauga, Ont. L5K 1B2 (Canada)

2006-07-01T23:59:59.000Z

404

Burnup concept for a long-life fast reactor core using MCNPX.  

SciTech Connect

This report describes a reactor design with a burnup concept for a long-life fast reactor core that was evaluated using Monte Carlo N-Particle eXtended (MCNPX). The current trend in advanced reactor design is the concept of a small modular reactor (SMR). However, very few of the SMR designs attempt to substantially increase the lifetime of a reactor core, especially without zone loading, fuel reshuffling, or other artificial mechanisms in the core that %E2%80%9Cflatten%E2%80%9D the power profile, including non-uniform cooling, non-uniform moderation, or strategic poison placement. Historically, the limitations of computing capabilities have prevented acceptable margins in the temporal component of the spatial excess reactivity in a reactor design, due primarily to the error in burnup calculations. This research was performed as an initial scoping analysis into the concept of a long-life fast reactor. It can be shown that a long-life fast reactor concept can be modeled using MCNPX to predict burnup and neutronics behavior. The inherent characteristic of this conceptual design is to minimize the change in reactivity over the lifetime of the reactor. This allows the reactor to operate substantially longer at full power than traditional Light Water Reactors (LWRs) or other SMR designs. For the purpose of this study, a single core design was investigated: a relatively small reactor core, yielding a medium amount of power (~200 to 400 MWth). The results of this scoping analysis were successful in providing a preliminary reactor design involving metal U-235/U-238 fuel with HT-9 fuel cladding and sodium coolant at a 20% volume fraction.

Holschuh, Thomas Vernon,; Lewis, Tom Goslee,; Parma, Edward J.,

2013-02-01T23:59:59.000Z

405

Criticality Benchmark Analysis of the HTTR Annular Startup Core Configurations  

SciTech Connect

One of the high priority benchmarking activities for corroborating the Next Generation Nuclear Plant (NGNP) Project and Very High Temperature Reactor (VHTR) Program is evaluation of Japan's existing High Temperature Engineering Test Reactor (HTTR). The HTTR is a 30 MWt engineering test reactor utilizing graphite moderation, helium coolant, and prismatic TRISO fuel. A large amount of critical reactor physics data is available for validation efforts of High Temperature Gas-cooled Reactors (HTGRs). Previous international reactor physics benchmarking activities provided a collation of mixed results that inaccurately predicted actual experimental performance.1 Reevaluations were performed by the Japanese to reduce the discrepancy between actual and computationally-determined critical configurations.2-3 Current efforts at the Idaho National Laboratory (INL) involve development of reactor physics benchmark models in conjunction with the International Reactor Physics Experiment Evaluation Project (IRPhEP) for use with verification and validation methods in the VHTR Program. Annular cores demonstrate inherent safety characteristics that are of interest in developing future HTGRs.

John D. Bess

2009-11-01T23:59:59.000Z

406

Cutting-edge issues of core-collapse supernova theory  

SciTech Connect

Based on multi-dimensional neutrino-radiation hydrodynamic simulations, we report several cutting-edge issues about the long-veiled explosion mechanism of core-collapse supernovae (CCSNe). In this contribution, we pay particular attention to whether three-dimensional (3D) hydrodynamics and/or general relativity (GR) would or would not help the onset of explosions. By performing 3D simulations with spectral neutrino transport, we show that it is more difficult to obtain an explosion in 3D than in 2D. In addition, our results from the first generation of full general relativistic 3D simulations including approximate neutrino transport indicate that GR can foster the onset of neutrino-driven explosions. Based on our recent parametric studies using a light-bulb scheme, we discuss impacts of nuclear energy deposition behind the supernova shock and stellar rotation on the neutrino-driven mechanism, both of which have yet to be included in the self-consistent 3D supernova models. Finally we give an outlook with a summary of the most urgent tasks to extract the information about the explosion mechanisms from multi-messenger CCSN observables.

Kotake, Kei [Department of Applied Physics, Faculty of Science, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180 (Japan); Nakamura, Ko [Faculty of Science and Engineering, Waseda University, Ohkubo 3-4-1, Shinjuku, Tokyo, 169-8555 (Japan); Kuroda, Takami [Department Physik, Universität Basel, Klingelbergstrasse 82, 4056 Basel (Switzerland); Takiwaki, Tomoya [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo, 181-8588 (Japan)

2014-05-02T23:59:59.000Z

407

FIBWR: a steady-state core flow distribution code for boiling water reactors code verification and qualification report. Final report  

SciTech Connect

A steady-state core flow distribution code (FIBWR) is described. The ability of the recommended models to predict various pressure drop components and void distribution is shown by comparison to the experimental data. Application of the FIBWR code to the Vermont Yankee Nuclear Power Station is shown by comparison to the plant measured data.

Ansari, A.F.; Gay, R.R.; Gitnick, B.J.

1981-07-01T23:59:59.000Z

408

Design of Scalable Java Communication Middleware for Multi-Core Systems  

Science Journals Connector (OSTI)

......cache, implemented as an Intel Smart Cache, where each core can...L2 256KB L2 256KB L2 20MB L3 Smart Cache Core 0 Core 1 Core 2 Core...large-message transfers in smdev benefit more than the intra-processor...ger sort (IS) and multi-grid (MG), measuring the performance......

Sabela Ramos; Guillermo L. Taboada; Roberto R. Expósito; Juan Touriño; Ramón Doallo

2013-02-01T23:59:59.000Z

409

Concentric core optical fiber with multiple-mode signal transmission  

DOE Patents (OSTI)

A concentric core optical fiber provides for the simultaneous but independent transmission of signals over a single optical fiber. The concentric optical fiber is constructed of a single-mode or multimode inner optical fiber defined by a core and a cladding of a lower index of refraction than the core and an outer optical fiber defined by additional cladding concentrically disposed around the cladding and of an index of refraction lower than the first mentioned cladding whereby the latter functions as the core of the outer optical fiber. By employing such an optical fiber construction with a single-mode inner core or optical fiber, highly sensitive interferometric and stable less sensitive amplitude based sensors can be placed along the same length of a concentric core optical fiber. Also, by employing the concentric core optical fiber secure telecommunications can be achieved via the inner optical fiber since an intrusion of the concentric optical fiber will first cause a variation in the light being transmitted through the outer optical fiber and this variation of light being used to trigger a suitable alarm indicative of the intrusion.

Muhs, Jeffrey D. (Lenoir City, TN)

1997-01-01T23:59:59.000Z

410

Preliminary engineering design of sodium-cooled CANDLE core  

Science Journals Connector (OSTI)

The CANDLE burning process is characterized by the autonomous shifting of burning region with constant reactivity and constant spacial power distribution. Evaluations of such critical burning process by using widely used neutron diffusion and burning codes under some realistic engineering constraints are valuable to confirm the technical feasibility of the CANDLE concept and to put the idea into concrete core design. In the first part of this paper it is discussed that whether the sustainable and stable CANDLE burning process can be reproduced even by using conventional core analysis tools such as SLAROM and CITATION-FBR. As a result it is certainly possible to demonstrate it if the proper core configuration and initial fuel composition required as CANDLE core are applied to the analysis. In the latter part an example of a concrete image of sodium cooled metal fuel 2000MWt rating CANDLE core has been presented by assuming an emerging inevitable technology of recladding. The core satisfies engineering design criteria including cladding temperature pressure drop linear heat rate and cumulative damage fraction (CDF) of cladding fast neutron fluence and sodium void reactivity which are defined in the Japanese FBR design project. It can be concluded that it is feasible to design CADLE core by using conventional codes while satisfying some realistic engineering design constraints assuming that recladding at certain time interval is technically feasible.

2012-01-01T23:59:59.000Z

411

Thermal hydraulic method for whole core design analysis of an HTGR  

SciTech Connect

A new thermal hydraulic method and initial results are presented for core-wide steady state analysis of prismatic High Temperature Gas-Cooled Reactors (HTGR). The method allows for the complete solution of temperature and coolant mass flow distribution by solving quasi-steady energy balances for the discretized core. Assembly blocks are discretized into unit cells for which the average temperature of each unit cell is determined. Convective heat removal is coupled to the unit cell energy balances by a 1-D axial flow model. The flow model uses established correlations for friction factor and Nusselt number. Bypass flow is explicitly calculated by using an initial guess for mass flow distribution and determining the exit pressure of each flow channel. The mass flow distribution is updated until a uniform core exit pressure condition is reached. Results are obtained for the MHTGR-350 with emphasis on the change in thermal hydraulic parameters due to various steady state power profiles and bypass gap widths. Steady state temperature distribution and its variations are discussed. (authors)

Huning, A. J.; Garimella, S. [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA (United States)

2013-07-01T23:59:59.000Z

412

Structure of a Folding Intermediate Reveals the Interplay Between Core and Peripheral Elements in RNA Folding  

SciTech Connect

Though the molecular architecture of many native RNA structures has been characterized, the structures of folding intermediates are poorly defined. Here, we present a nucleotide-level model of a highly structured equilibrium folding intermediate of the specificity domain of the Bacillus subtilis RNase P RNA, obtained using chemical and nuclease mapping, circular dichroism spectroscopy, small-angle X-ray scattering and molecular modeling. The crystal structure indicates that the 154 nucleotide specificity domain is composed of several secondary and tertiary structural modules. The structure of the intermediate contains modules composed of secondary structures and short-range tertiary interactions, implying a sequential order of tertiary structure formation during folding. The intermediate lacks the native core and several long-range interactions among peripheral regions, such as a GAAA tetraloop and its receptor. Folding to the native structure requires the local rearrangement of a T-loop in the core in concert with the formation of the GAAA tetraloop-receptor interaction. The interplay of core and peripheral structure formation rationalizes the high degree of cooperativity observed in the folding transition leading to the native structure.

Baird, Nathan J.; Westhof, Eric; Qin, Hong; Pan, Tao; Sosnick, Tobin R. (UC); (CNFRS)

2010-07-13T23:59:59.000Z

413

THR-TH: a high-temperature gas-cooled nuclear reactor core thermal hydraulics code  

SciTech Connect

The ORNL version of PEBBLE, the (RZ) pebble bed thermal hydraulics code, has been extended for application to a prismatic gas cooled reactor core. The supplemental treatment is of one-dimensional coolant flow in up to a three-dimensional core description. Power density data from a neutronics and exposure calculation are used as the basic information for the thermal hydraulics calculation of heat removal. Two-dimensional neutronics results may be expanded for a three-dimensional hydraulics calculation. The geometric description for the hydraulics problem is the same as used by the neutronics code. A two-dimensional thermal cell model is used to predict temperatures in the fuel channel. The capability is available in the local BOLD VENTURE computation system for reactor core analysis with capability to account for the effect of temperature feedback by nuclear cross section correlation. Some enhancements have also been added to the original code to add pebble bed modeling flexibility and to generate useful auxiliary results. For example, an estimate is made of the distribution of fuel temperatures based on average and extreme conditions regularly calculated at a number of locations.

Vondy, D.R.

1984-07-01T23:59:59.000Z

414

Seismic diagnostics of mixing beyond the convective core in intermediate mass main-sequence stars  

E-Print Network (OSTI)

We study prospects for seismic sounding the layer of a partial mixing above the convective core in main-sequence stars with masses in the 1.2 -- 1.9 solar mass range. There is an initial tendency to an increase of convective core mass in such stars and this leads to ambiguities in modeling. Solar-like oscillations are expected to be excited in such objects. Frequencies of such oscillations provide diagnostics, which are sensitive to the structure of the innermost part of the star and they are known as the small separations. We construct evolutionary models of stars in this mass range assuming various scenarios for element mixing, which includes formation of element abundance jumps, as well as semiconvective and overshooting layers. We find that the three point small separations employing frequencies of radial and dipole modes provide the best probe of the element distribution above the convective core. With expected accuracy of frequency measurement from the space experiments, a discrimination between various scenarios should be possible.

B. L. Popielski; W. A. Dziembowski

2005-05-25T23:59:59.000Z

415

High-temperature superconducting magnet for use in saturated core FCL  

Science Journals Connector (OSTI)

A HTS magnet system used in a saturated core Fault Current Limiter (FCL) device is described. The superconducting magnet, operating in DC mode, is used in such FCL design for saturating the magnetic core and maintaining low device impedance under nominal conditions. The unique design of the FCL poses constrains on the DC HTS magnet. A model which meets all the necessary special requirements have been realized in a compact magnet design that is optimized for its electrical characteristics while minimizing its mass and volume. The coil, made of Bi-2223 tapes, has 50000 Ampere-turns required to maintain the core in a saturated state at nominal current in the limiting circuit. Unique, nonmagnetic cryostat made of Delrin was used. Cooling of the coil has been realized by two cold heads: one double-stage head that provides a cooling power of 6 W at 20 K and a single-stage head with a cooling capability of 40W at 70 K. This magnetic system has been successfully integrated and tested in a 120 kVA FCL model. The design, characteristics and tests of this magnetic system are described.

Z Bar-Haim; A Friedman; Y Wolfus; V Rozenshtein; F Kopansky; Z Ron; E Harel; N Pundak; Y Yeshurun

2008-01-01T23:59:59.000Z

416

Automatic whole core depletion and criticality calculations by MCNPX 2.7.0  

SciTech Connect

Different approaches to perform automatic whole core criticality and depletion calculations in a research reactor using MCNPX 2.7.0 are presented. An approximate method is to use the existing symmetries of the burned fuel material distribution in the core, i.e., the axial, radial and azimuth symmetries around the core center, in order to significantly reduce the computation time. In this case it is not necessary to give a unique material number to each burn up cell. Cells having similar burn up and power, achieved during similar irradiation history at same initial fuel composition, will experience similar composition evolution and can therefore be given the same material number. To study the impact of the number of unique burn up materials on the computation time and utilized RAM memory, several MCNPX models have been developed. The paper discusses the accuracy of the model on comparison with measurements of BR2 operation cycles in function of the number of unique burn up materials and the impact of the used Q-value (MeV/fission) of the recoverable fission energy. (authors)

Kalcheva, S.; Koonen, E. [SCKCEN, BR2 Reactor Dept., Boeretang 200, 2400 Mol (Belgium)

2012-07-01T23:59:59.000Z

417

ACCU Core Sampling/Storage Device for VOC Analysis  

SciTech Connect

The Accu Core sampler system consists of alternating cylindrical clear acrylic sections and one-inch cylindrical stainless steel sections arranged in clear shrink wrap. The set of alternating acrylic and stainless steel sections in the shrink wrap are designed to fit in a Geoprobe dual-tube penetrometer for collection of continuous soil cores. The clear acrylic sections can have 1/2-inch access holes for easy soil headspace screening without violating the integrity of the adjacent stainless steel sections. The Accu Core sampler system can be used to store a soil sample collected in the stainless steel section by capping the ends of the section so it becomes a sample storage container. The sampler system can also be used to collect a subsurface soil sample in one of the sections that can be directly extruded from the section into a container for storage during shipment to the laboratory. In addition, the soil in a sampler section can be quickly sub-sampled using a coring tool and extruded into a storage container so the integrity of the soil is not disrupted and the potential for VOC loss during sub-sampling is greatly reduced. A field validation study was conducted to evaluate the performance of the Accu Core sampler to store VOC soil samples during transportation to the laboratory for analysis and to compare the performance of the Accu Core with current sampling and storage techniques, all of which require sub-sampling when the soil sample is brought to the surface. During some of the validation testing, the acrylic sections having access holes for headspace screening were included in the Accu Core sampler configuration and soil in these sections was screened to show the usefulness of the sample screening capability provided by the Accu Core system. This report presents the results of the field validation study as well as recommendations for the Accu Core sampler system.

Susan S. Sorini; John F. Schabron; Mark M. Sanderson

2007-04-30T23:59:59.000Z

418

Core Analysis At Dunes Geothermal Area (1976) | Open Energy Information  

Open Energy Info (EERE)

Dunes Geothermal Area (1976) Dunes Geothermal Area (1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Analysis At Dunes Geothermal Area (1976) Exploration Activity Details Location Dunes Geothermal Area Exploration Technique Core Analysis Activity Date 1976 Usefulness not indicated DOE-funding Unknown Exploration Basis Fracture analysis to determine if sealing or open fractures exist Notes Core samples show diagenesis superimposed on episodic fracturing and fracture sealing. The minerals that fill fractures show significant temporal variations. Fracture sealing and low fracture porosity imply that only the most recently formed fractures are open to fluids. References Michael L. Batzle; Gene Simmons (1 January 1976) Microfractures in rocks from two geothermal areas

419

Core Analysis At Raft River Geothermal Area (1976) | Open Energy  

Open Energy Info (EERE)

6) 6) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Core Analysis Activity Date 1976 Usefulness not indicated DOE-funding Unknown Exploration Basis Fracture analysis to determine if sealing or open fractures exist Notes Core samples show diagenesis superimposed on episodic fracturing and fracture sealing. The minerals that fill fractures show significant temporal variations. Fracture sealing and low fracture porosity imply that only the most recently formed fractures are open to fluids. References Michael L. Batzle; Gene Simmons (1 January 1976) Microfractures in rocks from two geothermal areas Retrieved from "http://en.openei.org/w/index.php?title=Core_Analysis_At_Raft_River_Geothermal_Area_(1976)&oldid=47383

420

Experimental studies of 6000-litre LMFBR cores at ZPPR  

SciTech Connect

The ZPPR-10 program has provided basic physics data for large two-zone conventional LMFBR cores. The early assemblies, 10A and 10B, had core volumes of 4600 litres. The assemblies reported here have core volumes of 6000 litres and represent 900 MW(e) reactors. The measurements emphasized the spatial variation of reaction rate distribution and control rod worths for configurations having 19 and 31 control rod positions. Two configurations with rods inserted were made critical by fuel additions in the later phases. A number of sodium void reactivities were measured. Analysis was made with ENDF/B-IV data.

Carpenter, S.G.; Collins, P.J.; Beck, C.L.; Gasidlo, J.M.; Goin, R.W.; Kaiser, R.E.; Maddison, D.W.; Olsen, D.N.

1980-01-01T23:59:59.000Z

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


421

Numerical Simulation of Two-Phase Flow in Severely Damaged Core Geometries  

SciTech Connect

In the event of a severe accident in a nuclear reactor, the oxidation, dissolution and collapse of fuel rods is likely to change dramatically the geometry of the core. A large part of the core would be damaged and would look like porous medium made of randomly distributed pellet fragments, broken claddings and relocated melts. Such a complex medium must be cooled in order to stop the accident progression. IRSN investigates the effectiveness of the water re-flooding mechanism in cooling this medium where complex two-phase flows are likely to exist. A macroscopic model for the prediction of the cooling sequence was developed for the ICARE/CATHARE code (IRSN mechanistic code for severe accidents). It still needs to be improved and assessed. It appears that a better understanding of the flow at the pore scale is necessary. As a result, a direct numerical simulation (DNS) code was developed to investigate the local features of a two-phase flow in complex geometries. In this paper, the Cahn-Hilliard model is used to simulate flows of two immiscible fluids in geometries representing a damaged core. These geometries are synthesized from experimental tomography images (PHEBUS-FP project) in order to study the effects of each degradation feature, such as displacement and fragmentation of the fuel rods and claddings, on the two-phase flow. For example, the presence of fragmented fuel claddings is likely to enhance the trapping of the residual phase (either steam or water) within the medium which leads to less flow fluctuations in the other phase. Such features are clearly shown by DNS calculations. From a series of calculations where the geometry of the porous medium is changed, conclusions are drawn for the impact of rods damage level on the characteristics of two-phase flow in the core. (authors)

Meekunnasombat, Phongsan; Fichot, Florian [Institute of Radioprotection and Nuclear Safety - IRSN, BP 17 - 92262 Fontenay-aux-Roses Cedex 31, avenue de la Division Leclerc 92260 Fontenay-aux-Roses (France); Quintard, Michel [Institut de Mecanique des Fluides de Toulouse, 1 Allee du Professeur Camille Soula, 31400 Toulouse (France)

2006-07-01T23:59:59.000Z

422

Turbulence and cooling in galaxy cluster cores  

Science Journals Connector (OSTI)

......2012). Thus, in our models energy is deposited via homogeneous...turbulence, with mechanical energy input. To prevent catastrophic...Vazquez-Semadeni, Gazol Scalo 2000; Audit Hennebelle 2005). Our paper...et-al. (2010), the feedback energy was directly added to internal......

Nilanjan Banerjee; Prateek Sharma

2014-01-01T23:59:59.000Z

423

A statistical study of the geological limits to Advanced Piston Coring: ODP Legs 101-149  

E-Print Network (OSTI)

The Advanced Piston Corer (APC), a soft sediment coring system developed from the hydraulic piston corer (HPC), allows recovery of ocean sediments with minimal coring disturbance. As a coring too[, the APC system is subject to limitations imposed...

Lee, Yir-Der Eddy

2012-06-07T23:59:59.000Z

424

Core Analysis At Raft River Geothermal Area (2011) | Open Energy  

Open Energy Info (EERE)

2011) 2011) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Core Analysis Activity Date 2011 Usefulness not indicated DOE-funding Unknown Exploration Basis Explore for development of an EGS demonstration project Notes Core was obtained from RRG-3C. The sample is a brecciated and altered siltstone from the base of the Tertiary sequence and is similar to rocks at the base of the Tertiary deposits in RRG-9. The results of thermal and quasi-static mechanical property measurements that were conducted on the core sample are presented. References Jones, C.; Moore, J.; Teplow, W.; Craig, S. (1 January 2011) GEOLOGY AND HYDROTHERMAL ALTERATION OF THE RAFT RIVER GEOTHERMAL SYSTEM, IDAHO Retrieved from "http://en.openei.org/w/index.php?title=Core_Analysis_At_Raft_River_Geothermal_Area_(2011)&oldid=473834

425

Probing Core-Hole Localization in Molecular Nitrogen  

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

Probing Core-Hole Localization in Molecular Nitrogen Print Probing Core-Hole Localization in Molecular Nitrogen Print The behavior of the core hole created in molecular x-ray photoemission experiments has provided molecular scientists with a valuable window through which to probe the electronic structure and dynamics of molecules. But the answer to one fundamental quantum question-whether the core hole is localized or delocalized-has remained elusive for diatomic molecules in which both atoms are the same element. An international team of scientists from the University of Frankfurt in Germany, Berkeley Lab, Kansas State University, and Auburn University has now resolved the issue with an appropriate twist of quantum fuzziness. By means of coincident detection of the photoelectron ejected from molecular nitrogen and the Auger electron emitted femtoseconds later, the team found that how the measurements are done determines which description-localized or delocalized-is valid.

426

Mineral Deformation at Earth's Core-Mantle Boundary  

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

Mineral Deformation at Earth's Core-Mantle Boundary Print Mineral Deformation at Earth's Core-Mantle Boundary Print Earth is a dynamic planet in which convection takes place on the scale of thousands of kilometers. Because Earth is mostly solid (except for its liquid-iron outer core), this convection causes deformation of solid rocks by plastic flow. At the core-mantle boundary (CMB), 2900 km deep, seismologists have discovered that seismic waves travel faster in certain directions. This seismic anisotropy appears to be related to the deformation of the constituent minerals. To understand the deformation mechanisms of mineral phases at this depth, researchers from Yale and UC Berkeley re-created the ultrahigh pressures of the deep Earth at ALS Beamline 12.2.2 while conducting in situ x-ray diffraction experiments to probe changes in crystal orientations.

427

Core Analysis At Coso Geothermal Area (1980) | Open Energy Information  

Open Energy Info (EERE)

Core Analysis At Coso Geothermal Area (1980) Core Analysis At Coso Geothermal Area (1980) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Core Analysis Activity Date 1980 Usefulness not indicated DOE-funding Unknown Exploration Basis Determine the heat transfer mechanism Notes In an investigation of the thermal regime of this Basin and Range geothermal area, temperature measurements were made in 25 shallow and 1 intermediate depth borehole. Thermal conductivity measurements were made on 312 samples from cores and drill cuttings. The actual process by which heat is transferred is rather complex; however, the heat flow determinations can be divided into two groups. The first group, less than 4.0 HFU, are indicative of regions with primarily conductive regimes, although

428

Probing Core-Hole Localization in Molecular Nitrogen  

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

Probing Core-Hole Localization in Molecular Nitrogen Print Probing Core-Hole Localization in Molecular Nitrogen Print The behavior of the core hole created in molecular x-ray photoemission experiments has provided molecular scientists with a valuable window through which to probe the electronic structure and dynamics of molecules. But the answer to one fundamental quantum question-whether the core hole is localized or delocalized-has remained elusive for diatomic molecules in which both atoms are the same element. An international team of scientists from the University of Frankfurt in Germany, Berkeley Lab, Kansas State University, and Auburn University has now resolved the issue with an appropriate twist of quantum fuzziness. By means of coincident detection of the photoelectron ejected from molecular nitrogen and the Auger electron emitted femtoseconds later, the team found that how the measurements are done determines which description-localized or delocalized-is valid.

429

Mineral Deformation at Earth's Core-Mantle Boundary  

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

Mineral Deformation at Earth's Core-Mantle Boundary Print Mineral Deformation at Earth's Core-Mantle Boundary Print Earth is a dynamic planet in which convection takes place on the scale of thousands of kilometers. Because Earth is mostly solid (except for its liquid-iron outer core), this convection causes deformation of solid rocks by plastic flow. At the core-mantle boundary (CMB), 2900 km deep, seismologists have discovered that seismic waves travel faster in certain directions. This seismic anisotropy appears to be related to the deformation of the constituent minerals. To understand the deformation mechanisms of mineral phases at this depth, researchers from Yale and UC Berkeley re-created the ultrahigh pressures of the deep Earth at ALS Beamline 12.2.2 while conducting in situ x-ray diffraction experiments to probe changes in crystal orientations.

430

Core Holes At Long Valley Caldera Geothermal Area (Benoit, 1984...  

Open Energy Info (EERE)

Basis Several core holes were also drilled in the caldera's west moat by Phillips Petroleum Company in 1982, including: PLV-1, drilled to approximately 711 m depth PLV-2,...

431

High-voltage air-core pulse transformers  

SciTech Connect

General types of air core pulse transformers designed for high voltage pulse generation and energy transfer applications are discussed with special emphasis on pulse charging systems which operate up to the multi-megavolt range. The design, operation, dielectric materials, and performance are described. It is concluded that high voltage air core pulse transformers are best suited to applications outside the normal ranges of conventional magnetic core transformers. In general these include charge transfer at high power levels and fast pulse generation with comparatively low energy. When properly designed and constructed, they are capable of delivering high energy transfer efficiency and have demonstrated superior high voltage endurance. The principal disadvantage of high voltage air core transformers is that they are not generally available from commercial sources. Consequently, the potential user must become thoroughly familiar with all aspects of design, fabrication and system application before he can produce a high performance transformer system. (LCL)

Rohwein, G. J.

1981-01-01T23:59:59.000Z

432

Core–Shell Catalysts in PEMFC Cathode Environments  

Science Journals Connector (OSTI)

A wide variety of core–shell electrocatalysts have been investigated in recent years, showing benefits for the oxygen reduction reaction (ORR) in acid electrolytes. Particularly high values of activity per gram o...

Sarah Ball

2013-01-01T23:59:59.000Z

433

Synthesis Dependent Core Level Binding Energy Shift in the Oxidation...  

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

Energy Shift in the Oxidation State ofPlatinum Coated on Ceria–Titania and its Synthesis Dependent Core Level Binding Energy Shift in the Oxidation State ofPlatinum Coated...

434

Plug's GenCore supports rural telephone network  

Science Journals Connector (OSTI)

The Oneida County rural telephone network in upstate New York is benefiting from backup power provided by a 5 kWe GenCore® 5T48 fuel cell system supplied by Plug Power.

2004-01-01T23:59:59.000Z

435

Webinar: Review Core Competencies for Appraisers to Value Green Buildings  

Energy.gov (U.S. Department of Energy (DOE))

The Appraisal Foundation is developing a document to describe the fundamentals of the Valuation of Green Buildings. This document highlights the core skill sets and data necessary for appraisers to...

436

Evidence for a Weak Iron Core at Earth's Center  

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

Iron Core at Earth's Center Print Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial plane-why? One theory...

437

Mineral Deformation at Earth's Core-Mantle Boundary  

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

Mineral Deformation at Earth's Core-Mantle Boundary Print Earth is a dynamic planet in which convection takes place on the scale of thousands of kilometers. Because Earth is mostly...

438

Doubling Estimates of Light Elements in the Earth's Core | Advanced...  

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

relation of both hcp-Fe and the iron-silicon alloy at 300 K. The inner core of the Earth is the remotest area on the globe, mostly impossible to study directly. It is an area...

439

Earth's Core Reveals an Inner Weakness | Advanced Photon Source  

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

their results to core conditions and found that the strength of iron deep within the Earth is lower than previously thought. This weakness may explain how the crystal structure...

440

Mineral Deformation at Earth's Core-Mantle Boundary  

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

Deformation at Earth's Core-Mantle Boundary Print Wednesday, 31 August 2011 00:00 Earth is a dynamic planet in which convection takes place on the scale of thousands of...

Note: This page contains sample records for the topic "larger core models" 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

Serially connected solid oxide fuel cells having monolithic cores  

DOE Patents (OSTI)

A solid oxide fuel cell for electrochemically combining fuel and oxidant for generating galvanic output, wherein the cell core has an array of cell segments electrically serially connected in the flow direction, each segment consisting of electrolyte walls and interconnect that are substantially devoid of any composite inert materials for support. Instead, the core is monolithic, where each electrolyte wall consists of thin layers of cathode and anode materials sandwiching a thin layer of electrolyte material therebetween. Means direct the fuel to the anode-exposed core passageways and means direct the oxidant to the cathode-exposed core passageways; and means also direct the galvanic output to an exterior circuit. Each layer of the electrolyte composite materials is of the order of 0.002-0.01 cm thick; and each layer of the cathode and anode materials is of the order of 0.002-0.05 cm thick. Between 2 and 50 cell segments may be connected in series.

Herceg, Joseph E. (Naperville, IL)

1987-01-01T23:59:59.000Z

442

Loading rubidium atoms into a hollow core fiber  

E-Print Network (OSTI)

We demonstrate a procedure for cooling, trapping, and transferring rubidium atoms into a hollow core photonic band gap fiber. The atoms are first collected in a magneto-optical trap (MOT) and then cooled using polarization ...

Chu, Yiwen

2007-01-01T23:59:59.000Z

443

Sandia National Laboratories: III-Nitride core-shell nanowire...  

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

Sector III-Nitride core-shell nanowire arrayed solar cells On April 27, 2012, in Energy, Energy Efficiency, News, News & Events, Solid-State Lighting In a new EFRC-supported...

444

What Could a Million Cores Do To Solve Integer Programs?  

E-Print Network (OSTI)

What Could a Million Cores Do To Solve Integer Programs? Thorsten Koch(koch ***at*** zib.de) Ted Ralphs(ted ***at*** lehigh.edu) Yuji Shinano(shinano ...

Thorsten Koch

445

Results From a Transparent Open-Core Downdraft Gasifier  

Science Journals Connector (OSTI)

A transparent quartz reactor has allowed observations on the process of gasification of biomass within an open-core gasifier. This has enabled the individual stages in ... and quantitatively described. Results ac...

J. B. Milligan; G. D. Evans…

1993-01-01T23:59:59.000Z

446

Complex foamed aluminum parts as permanent cores in aluminum castings  

SciTech Connect

The feasibility of complex shaped aluminum foam parts as permanent cores in aluminum castings has been investigated. The foamed samples were prepared by injection of the foam into sand molds. It turned out that sound castings can be produced if the foam core is properly preheated and/or surface treated before casting. The effect of the foam core on the performance of the casting was evaluated by in compression testing and by measuring structural damping. The gain in the related properties turned out to be much higher than the weight increase of the casting due to the presence of the core. The weight increase may be partially offset through a reduction of the wall-thickness of the shell.

Simancik, F. [Inst. of Materials and Machine Mechanics, Bratislava (Slovakia); Schoerghuber, F. [Illichmann GmbH, Altmuenster (Austria)

1998-12-31T23:59:59.000Z

447

Solid0Core Heat-Pipe Nuclear Batterly Type Reactor  

SciTech Connect

This project was devoted to a preliminary assessment of the feasibility of designing an Encapsulated Nuclear Heat Source (ENHS) reactor to have a solid core from which heat is removed by liquid-metal heat pipes (HP).

Ehud Greenspan

2008-09-30T23:59:59.000Z

448

Cache coherence strategies in a many-core processor  

E-Print Network (OSTI)

Caches are frequently employed in memory systems, exploiting memory locality to gain advantages in high-speed performance and low latency. However, as computer processor core counts increase, maintaining coherence between ...

Celio, Christopher P

2009-01-01T23:59:59.000Z

449

Descriptive logs, skeletonized samples, and photographs of core...  

Open Energy Info (EERE)

of core from Presco Energy's thermal gradient wells P3-1, P10-1, and P32-2 in the Rye Patch area, Pershing County, Nevada Jump to: navigation, search OpenEI Reference LibraryAdd...

450

Core Holes At Valles Caldera - Sulphur Springs Geothermal Area...  

Open Energy Info (EERE)

Dennis L. Nielson, Pisto Larry, C.W. Criswell, R. Gribble, K. Meeker, J.A. Musgrave, T. Smith, D. Wilson (1989) Scientific Core Hole Valles Caldera No. 2B (VC-2B), New Mexico:...

451

The Chemistry of Cold Interstellar Cloud Cores Eric Herbst  

E-Print Network (OSTI)

Chapter 1 The Chemistry of Cold Interstellar Cloud Cores Eric Herbst Department of Physics and Their Chemistry . . . . . . . . . . . . . 4 1.2 Gas-Phase Chemical Processes . . . . . . . . . . . . . . . . . . . . . . . . . . 13 1.2.4 Organic Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 1.2.5 Negative

Millar, Tom

452

The Vital Core Connectivity Problem Sylvia Boyd and Amy Cameron  

E-Print Network (OSTI)

The Vital Core Connectivity Problem Sylvia Boyd and Amy Cameron School of Information Technology. Sylvia Boyd: sylvia@site.uottawa.ca, Amy Cameron: acame097@uottawa.ca Published in: A. Cameron

Boyd, Sylvia

453

www.nasa.gov Core Flight Software System  

E-Print Network (OSTI)

architecture features a plug-and-play software executive called the Core Flight Executive (cFE), a re 2009, certified cFE for flight. Several upcoming missions, including the Global Precipitation

Christian, Eric

454

A Critique of Core--Collapse Supernova Theory Circa 1997  

E-Print Network (OSTI)

There has been a new infusion of ideas in the study of the mechanism and early character of core--collapse supernovae. However, despite recent conceptual and computational progress, fundamental questions remain. Some are summarize herein.

Adam Burrows

1997-03-02T23:59:59.000Z

455

A Critique of Core-Collapse Supernova Theory Circa 1997  

E-Print Network (OSTI)

There has been a new infusion of ideas in the study of the mechanism and early character of core--collapse supernovae. However, despite recent conceptual and computational progress, fundamental questions remain. Some are summarize herein.

Burrows, A

1998-01-01T23:59:59.000Z

456

Mineral Deformation at Earth's Core-Mantle Boundary  

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

Mineral Deformation at Earth's Core-Mantle Boundary Print Mineral Deformation at Earth's Core-Mantle Boundary Print Earth is a dynamic planet in which convection takes place on the scale of thousands of kilometers. Because Earth is mostly solid (except for its liquid-iron outer core), this convection causes deformation of solid rocks by plastic flow. At the core-mantle boundary (CMB), 2900 km deep, seismologists have discovered that seismic waves travel faster in certain directions. This seismic anisotropy appears to be related to the deformation of the constituent minerals. To understand the deformation mechanisms of mineral phases at this depth, researchers from Yale and UC Berkeley re-created the ultrahigh pressures of the deep Earth at ALS Beamline 12.2.2 while conducting in situ x-ray diffraction experiments to probe changes in crystal orientations.

457

Quantum phases of dipolar soft-core bosons  

E-Print Network (OSTI)

We study the phase diagram of a system of soft-core dipolar bosons confined to a two-dimensional optical lattice layer. We assume that dipoles are aligned perpendicular to the layer such that the dipolar interactions are ...

Grimmer, D.

458

Validation of the neutron and gamma fields in the JSI TRIGA reactor using in-core fission and ionization chambers  

Science Journals Connector (OSTI)

Abstract CEA developed fission chambers and ionization chambers were utilized at the JSI TRIGA reactor to measure neutron and gamma fields. The measured axial fission rate distributions in the reactor core are generally in good agreement with the calculated values using the Monte Carlo model of the reactor thus verifying both the computational model and the fission chambers. In future, multiple absolutely calibrated fission chambers could be used for more accurate online reactor thermal power monitoring.

Gašper Žerovnik; Tanja Kaiba; Vladimir Radulovi?; Anže Jazbec; Sebastjan Rupnik; Loïc Barbot; Damien Fourmentel; Luka Snoj

2015-01-01T23:59:59.000Z

459

Modelling elements of Smart Grids – Enhancing the \\{OSeMOSYS\\} (Open Source Energy Modelling System) code  

Science Journals Connector (OSTI)

‘Smart Grids’ are expected to help facilitate a better integration of distributed storage and demand response options into power systems and markets. Quantifying the associated system benefits may provide valuable design and policy insights. Yet many existing energy system models are not able to depict various critical features associated with Smart Grids in a single comprehensive framework. These features may for example include grid stability issues in a system with several flexible demand types and storage options to help balance a high penetration of renewable energy. Flexible and accessible tools have the potential to fill this niche. This paper expands on the Open Source Energy Modelling System (OSeMOSYS). It describes how ‘blocks of functionality’ may be added to represent variability in electricity generation, a prioritisation of demand types, shifting demand, and storage options. The paper demonstrates the flexibility and ease-of-use of \\{OSeMOSYS\\} with regard to modifications of its code. It may therefore serve as a useful test-bed for new functionality in tools with wide-spread use and larger applications, such as MESSAGE, TIMES, MARKAL, or LEAP. As with the core code of OSeMOSYS, the functional blocks described in this paper are available in the public domain.

M. Welsch; M. Howells; M. Bazilian; J.F. DeCarolis; S. Hermann; H.H. Rogner

2012-01-01T23:59:59.000Z

460

Residual strain measurements on drill cores from Reydarfjordur, Iceland  

E-Print Network (OSTI)

RESIDUAL STRAIN MEASUREMENTS ON DRILL CORES FROM REYDARFJORDUR, ICELAND A Thesis BESIM BASLANGIC Submitted to the Office oi' Graduate Studies of Texas A&M University in partial fulfillment of the requirements I' or the degree of MAST...'ER OF SCIENCE May 1989 Major Subject: Geophysics RESIDUAL STRAIN MEASLREMENTS ON DRILL CORES FROM REYDARFJORDUR, ICELAVD A Thesis BESIM BASLANGIC Approved as to style and content by: Earl R. Hoskins (Chair of Committee) Richard L. Carlson (Member...

Baslangic, Besim

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "larger core models" 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

GCRA review and appraisal of HTGR reactor-core-design program. [HTGR-SC, -R, -NHSDR  

SciTech Connect

The reactor-core-design program has as its principal objective and responsibility the design and resolution of major technical issues for the reactor core and core components on a schedule consistent with the plant licensing and construction program. The task covered in this review includes three major design areas: core physics, core thermal and hydraulic performance fuel element design, and in-core fuel performance evaluation.

Not Available

1980-09-01T23:59:59.000Z

462

Magnetic Vortex Core Reversal by Low-Field Excitations  

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

Magnetic Vortex Core Reversal by Magnetic Vortex Core Reversal by Low-Field Excitations Magnetic Vortex Core Reversal by Low-Field Excitations Print Wednesday, 28 March 2007 00:00 In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very strong magnetic fields of around half a tesla (approximately one-third the field of the strongest permanent magnet) were previously thought to be necessary to accomplish this. At the ALS, a team of researchers from Germany, Belgium, and the U.S. has used time-resolved scanning transmission x-ray microscopy (STXM) to observe vortex motion and demonstrate the feasibility of using weak magnetic fields as low as 1.5 millitesla (mT) to reverse the direction of a vortex core. The observed switching mechanism, which can be understood within the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application to data storage technologies.

463

A MASSIVE PROTOSTAR FORMING BY ORDERED COLLAPSE OF A DENSE, MASSIVE CORE  

SciTech Connect

We present 30 and 40 {mu}m imaging of the massive protostar G35.20-0.74 with SOFIA-FORCAST. The high surface density of the natal core around the protostar leads to high extinction, even at these relatively long wavelengths, causing the observed flux to be dominated by that emerging from the near-facing outflow cavity. However, emission from the far-facing cavity is still clearly detected. We combine these results with fluxes from the near-infrared to mm to construct a spectral energy distribution (SED). For isotropic emission the bolometric luminosity would be 3.3 Multiplication-Sign 10{sup 4} L{sub Sun }. We perform radiative transfer modeling of a protostar forming by ordered, symmetric collapse from a massive core bounded by a clump with high-mass surface density, {Sigma}{sub cl}. To fit the SED requires protostellar masses {approx}20-34 M{sub Sun} depending on the outflow cavity opening angle (35 Degree-Sign -50 Degree-Sign ), and {Sigma}{sub cl} {approx} 0.4-1 g cm{sup -2}. After accounting for the foreground extinction and the flashlight effect, the true bolometric luminosity is {approx}(0.7-2.2) Multiplication-Sign 10{sup 5} L{sub Sun }. One of these models also has excellent agreement with the observed intensity profiles along the outflow axis at 10, 18, 31, and 37 {mu}m. Overall our results support a model of massive star formation involving the relatively ordered, symmetric collapse of a massive, dense core and the launching bipolar outflows that clear low-density cavities. Thus a unified model may apply for the formation of both low- and high-mass stars.

Zhang, Yichen; Tan, Jonathan C.; Telesco, Charles [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States)] [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); De Buizer, James M.; Sandell, Goeran; Shuping, Ralph [SOFIA-USRA, NASA Ames Research Center, MS 232-12, Building N232, P.O. Box 1, Moffett Field, CA 94035 (United States)] [SOFIA-USRA, NASA Ames Research Center, MS 232-12, Building N232, P.O. Box 1, Moffett Field, CA 94035 (United States); Beltran, Maria T. [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, Firenze I-50125 (Italy)] [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, Firenze I-50125 (Italy); Churchwell, Ed; Whitney, Barbara [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States)] [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States); McKee, Christopher F. [Department of Astronomy and Astrophysics, University of California, Berkeley, CA 94720 (United States)] [Department of Astronomy and Astrophysics, University of California, Berkeley, CA 94720 (United States); Staff, Jan E., E-mail: yc.zhang@astro.ufl.edu [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States)

2013-04-10T23:59:59.000Z

464

IceCube, DeepCore, PINGU and the indirect search for supersymmetric dark matter  

E-Print Network (OSTI)

The discovery of a particle that could be the lightest CP-even Higgs of the minimal supersymmetric extension of the Standard Model (MSSM) and the lack of evidence so far for supersymmetry at the LHC have many profound implications, including for the phenomenology of supersymmetric dark matter. In this study, we re-evaluate and give an update on the prospects for detecting supersymmetric neutralinos with neutrino telescopes, focussing in particular on the IceCube/DeepCore Telescope as well as on its proposed extension, PINGU. Searches for high-energy neutrinos from the Sun with IceCube probe MSSM neutralino dark matter models with the correct Higgs mass in a significant way. This is especially the case for neutralino dark matter models producing hard neutrino spectra, across a wide range of masses, while PINGU is anticipated to improve the detector sensitivity especially for models in the low neutralino mass range.

Paul Bergeron; Stefano Profumo

2013-12-16T23:59:59.000Z

465

Efficiency of static core turn-off in a system-on-a-chip with variation  

DOE Patents (OSTI)

A processor-implemented method for improving efficiency of a static core turn-off in a multi-core processor with variation, the method comprising: conducting via a simulation a turn-off analysis of the multi-core processor at the multi-core processor's design stage, wherein the turn-off analysis of the multi-core processor at the multi-core processor's design stage includes a first output corresponding to a first multi-core processor core to turn off; conducting a turn-off analysis of the multi-core processor at the multi-core processor's testing stage, wherein the turn-off analysis of the multi-core processor at the multi-core processor's testing stage includes a second output corresponding to a second multi-core processor core to turn off; comparing the first output and the second output to determine if the first output is referring to the same core to turn off as the second output; outputting a third output corresponding to the first multi-core processor core if the first output and the second output are both referring to the same core to turn off.

Cher, Chen-Yong; Coteus, Paul W; Gara, Alan; Kursun, Eren; Paulsen, David P; Schuelke, Brian A; Sheets, II, John E; Tian, Shurong

2013-10-29T23:59:59.000Z

466