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Note: This page contains sample records for the topic "models assessing surface" 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
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1

NOTES AND CORRESPONDENCE Surface Melting over Ice Shelves and Ice Sheets as Assessed from Modeled  

E-Print Network [OSTI]

NOTES AND CORRESPONDENCE Surface Melting over Ice Shelves and Ice Sheets as Assessed from Modeled of ice shelves and their progenitor ice sheets. To explore the magnitude of surface melt occurring over) and most of the Greenland Ice Sheet (GIS) by the year 2500. Capping CO2 concentrations at present

Meissner, Katrin Juliane

2

Surface Water Monitoring and Assessment (Ohio)  

Broader source: Energy.gov [DOE]

This law establishes criteria for three levels of credible data for a surface water quality monitoring and assessment program and establishes the necessary training and experience for persons to...

3

Integrated Assessment Modeling  

SciTech Connect (OSTI)

This paper discusses the role of Integrated Assessment models (IAMs) in climate change research. IAMs are an interdisciplinary research platform, which constitutes a consistent scientific framework in which the large-scale interactions between human and natural Earth systems can be examined. In so doing, IAMs provide insights that would otherwise be unavailable from traditional single-discipline research. By providing a broader view of the issue, IAMs constitute an important tool for decision support. IAMs are also a home of human Earth system research and provide natural Earth system scientists information about the nature of human intervention in global biogeophysical and geochemical processes.

Edmonds, James A.; Calvin, Katherine V.; Clarke, Leon E.; Janetos, Anthony C.; Kim, Son H.; Wise, Marshall A.; McJeon, Haewon C.

2012-10-31T23:59:59.000Z

4

Model Refinement for Economic Assessments of  

E-Print Network [OSTI]

Model Refinement for Economic Assessments of Hawai`i Clean Energy Policies: Scenario Selection agency thereof. #12;Model Refinement for Economic Assessments of Hawaii Clean Energy Policies Selection

5

Utility of Social Modeling for Proliferation Assessment - Preliminary Assessment  

SciTech Connect (OSTI)

This Preliminary Assessment draft report will present the results of a literature search and preliminary assessment of the body of research, analysis methods, models and data deemed to be relevant to the Utility of Social Modeling for Proliferation Assessment research. This report will provide: 1) a description of the problem space and the kinds of information pertinent to the problem space, 2) a discussion of key relevant or representative literature, 3) a discussion of models and modeling approaches judged to be potentially useful to the research, and 4) the next steps of this research that will be pursued based on this preliminary assessment. This draft report represents a technical deliverable for the NA-22 Simulations, Algorithms, and Modeling (SAM) program. Specifically this draft report is the Task 1 deliverable for project PL09-UtilSocial-PD06, Utility of Social Modeling for Proliferation Assessment. This project investigates non-traditional use of social and cultural information to improve nuclear proliferation assessment, including nonproliferation assessment, proliferation resistance assessments, safeguards assessments and other related studies. These assessments often use and create technical information about the State’s posture towards proliferation, the vulnerability of a nuclear energy system to an undesired event, and the effectiveness of safeguards. This project will find and fuse social and technical information by explicitly considering the role of cultural, social and behavioral factors relevant to proliferation. The aim of this research is to describe and demonstrate if and how social science modeling has utility in proliferation assessment.

Coles, Garill A.; Gastelum, Zoe N.; Brothers, Alan J.; Thompson, Sandra E.

2009-06-01T23:59:59.000Z

6

Model Fire Protection Assessment Guide  

Broader source: Energy.gov [DOE]

This Assessment guide covers the implementation of the DOE's responsibility of assuring that DOE and the DOE Contractors have established Fire Protection Programs that are at the level required for the area being assessed.

7

An Impact Assessment Model for Distributed Adaptive Security Situation Assessment*  

E-Print Network [OSTI]

1 An Impact Assessment Model for Distributed Adaptive Security Situation Assessment* Mark Heckman mechanism is not simply to stop attacks, but to protect a computing resource so that the resource can continue to perform its function. A computing resource, however, is only a component of a larger system

California at Davis, University of

8

Minimal model for spoof acoustoelastic surface states  

SciTech Connect (OSTI)

Similar to textured perfect electric conductors for electromagnetic waves sustaining artificial or spoof surface plasmons we present an equivalent phenomena for the case of sound. Aided by a minimal model that is able to capture the complex wave interaction of elastic cavity modes and airborne sound radiation in perfect rigid panels, we construct designer acoustoelastic surface waves that are entirely controlled by the geometrical environment. Comparisons to results obtained by full-wave simulations confirm the feasibility of the model and we demonstrate illustrative examples such as resonant transmissions and waveguiding to show a few examples of many where spoof elastic surface waves are useful.

Christensen, J., E-mail: jochri@fotonik.dtu.dk; Willatzen, M. [Department of Photonics Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Liang, Z. [College of Electronic Science and Technology, Shenzhen University, Shenzhen (China)

2014-12-15T23:59:59.000Z

9

Triazine herbcides: Ecological risk assessment in North American surface waters  

SciTech Connect (OSTI)

The triazine herbicides are some of the most widely used pesticides in North America. Some are found in surface waters in North America and risks to aquatic ecosystems are a possible concern. This paper presents the results of a comprehensive aquatic ecological risk assessment conducted using probabilistic risk assessment techniques. The assessment of exposure data concentrated on Midwestern us watersheds, the area of greatest triazine use in North America and showed that concentrations of some triazines rarely exceeded 20 {mu}g/L in rivers, streams, and reservoirs. The effects assessment showed that phytoplankton were the most sensitive organisms to triazines followed, in decreasing order of sensitivity, by macrophytes, benthic invertebrates, zooplankton and fish. Distribution analysis of sensitivity to atrazine showed 10th percentile of 37 {mu}g/L for LC50s in all organisms and 5.4 {mu}g/L for LC50s in algae and plants. Simazine showed 10th percentiles of 188 {mu}g/L for LC50s in all organisms and 27 {mu}g/L for LC50s in aquatic plants. Comparisons of the exposure and effects distributions showed low probabilities of exceeding the 10th percentiles of the sensitivity distributions. These results will be discussed in relation to the mechanism of action of these substances and other stressors in the environment.

Solomon, K.R. [Univ. of Guelph (Canada)

1996-10-01T23:59:59.000Z

10

Assessment of Molecular Modeling & Simulation  

SciTech Connect (OSTI)

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

None

2002-01-03T23:59:59.000Z

11

ASSESSMENT OF ECONOMIC PERFORMANCE OF MODEL PREDICTIVE  

E-Print Network [OSTI]

ASSESSMENT OF ECONOMIC PERFORMANCE OF MODEL PREDICTIVE CONTROL THROUGH VARIANCE/CONSTRAINT TUNING advanced process control (APC) strategies to deal with multivariable constrained control problems with an ultimate objective towards economic optimization. Any attempt to evaluate MPC performance should therefore

Huang, Biao

12

ORISE: Dose modeling and assessments  

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

or state regulatory compliance requirements are being met during the decontamination and decommissioning of nuclear facilities. Dose modeling is an important step in the...

13

Models and parameters for environmental radiological assessments  

SciTech Connect (OSTI)

This book presents a unified compilation of models and parameters appropriate for assessing the impact of radioactive discharges to the environment. Models examined include those developed for the prediction of atmospheric and hydrologic transport and deposition, for terrestrial and aquatic food-chain bioaccumulation, and for internal and external dosimetry. Chapters have been entered separately into the data base. (ACR)

Miller, C W [ed.] [ed.

1984-01-01T23:59:59.000Z

14

ORISE: Dose modeling and assessments  

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

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

15

Dyadic Green's functions and guided surface waves for a surface conductivity model of graphene  

E-Print Network [OSTI]

Dyadic Green's functions and guided surface waves for a surface conductivity model of graphene current in the presence of a surface conductivity model of graphene. The graphene is represented and transmission is presented, and surface wave propagation along graphene is studied via the poles

Hanson, George

16

Surface Vibrations in a Model Hcp Crystal  

E-Print Network [OSTI]

-1973. R. E. Allen, G. P. Alldredge, and F. W. de Wette, Phys. Rev. B 4, 1661 (3.971). 2R. E. Allen and F. W. de Wette, Phys. Rev. 179, 873 0.969). ..., and F. W. de Wette, Phys. Rev. B4, 1661 (1971). PHYSICA L RE VIE W 8 VOLUME 6, NUMBE R 2 15 JULY 1972 Surface Vibrations in a Model hcp Crystal R. E. Allen Department of Physics, Texas A @ M University, College Station, Texas 77843 and G. P...

Allen, Roland E.; Alldredg, GP; DEWITTE, FW.

1972-01-01T23:59:59.000Z

17

Diuse interface surface tension models in an expanding ow  

E-Print Network [OSTI]

Diuse interface surface tension models in an expanding ow Wangyi Liu, Andrea L. Bertozzi , and Theodore Kolokolnikov November 22, 2010 Abstract We consider a diusive interface surface tension model principle. 1 Background There is a need to develop simple computational models for surface tension

Soatto, Stefano

18

Assessing residential exposure to urban noise using environmental models: does the size of the local living  

E-Print Network [OSTI]

1 Assessing residential exposure to urban noise using environmental models: does the size on the quantification of the exposure level in a surface defined as the subject's exposure area. For residential residential buildings. Twelve noise exposure indicators have been used to assess inhabitants' exposure

Paris-Sud XI, Université de

19

Model assessment of protective barriers: Part 3  

SciTech Connect (OSTI)

Radioactive waste exists at the US Department of Energy's (DOE's) Hanford Site in a variety of locations, including subsurface grout and tank farms, solid waste burial grounds, and contaminated soil sites. Some of these waste sites may need to be isolated from percolating water to minimize the potential for transport of the waste to the ground water, which eventually discharges to the Columbia River. Multilayer protective barriers have been proposed as a means of limiting the flow of water through the waste sites (DOE 1987). A multiyear research program (managed jointly by Pacific Northwest Laboratory (PNL) and Westinghouse Hanford Company for the DOE) is aimed at assessing the performance of these barriers. One aspect of this program involves the use of computer models to predict barrier performance. Three modeling studies have already been conducted and a test plan was produced. The simulation work reported here was conducted by PNL and extends the previous modeling work. The purpose of this report are to understand phenomena that have been observed in the field and to provide information that can be used to improve hydrologic modeling of the protective barrier. An improved modeling capability results in better estimates of barrier performance. Better estimates can be used to improve the design of barriers and the assessment of their long-term performance.

Fayer, M.J.; Rockhold, M.L.; Holford, D.J.

1992-02-01T23:59:59.000Z

20

Numerical Modeling of Nonlinear Surface Waves caused by Surface Effect Ships Dynamics and Kinematics  

E-Print Network [OSTI]

Numerical Modeling of Nonlinear Surface Waves caused by Surface Effect Ships Dynamics and Kinematics Hong Gun Sung½ and Stephan T. Grilli¾ ½ Korea Ocean Research and Development Institute, Daejeon model fully nonlinear free surface waves caused by a translating dis- turbance made of a pressure patch

Grilli, Stéphan T.

Note: This page contains sample records for the topic "models assessing surface" 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

Assessing Uncertainty in Spatial Exposure Models for Air Pollution Health Effects Assessment  

E-Print Network [OSTI]

Holgate S. 2002. Air pollution and health. Lancet Brunekreef2006. Bayesian modeling of air pollution health effects withExposure Models for Air Pollution Health Effects Assessment

2007-01-01T23:59:59.000Z

22

The motion of kelp blades and the surface renewal model  

E-Print Network [OSTI]

We consider how the flapping of kelp blades may enhance the flux of nutrients to a blade, by stripping away the diffusive sub-layer and renewing the fluid at the blade surface. The surface renewal model explains the degree ...

Huang, Ivy

2011-01-01T23:59:59.000Z

23

Model for assessing bronchial mucus transport  

SciTech Connect (OSTI)

The authors propose a scheme for the assessment of regional mucus transport using inhaled Tc-99m aerosol particles and quantitative analysis of serial gamma-camera images. The model treats input to inner and intermediate lung regions as the total of initial deposition there plus subsequent transport into these regions from more peripheral airways. It allows for interregional differences in the proportion of particles deposited on the mucus-bearing conducting airways, and does not require a gamma image 24 hr after particle inhalation. Instead, distribution of particles reaching the respiratory bronchioles or alveoli is determined from a Kr-81m ventilation image, while the total amount of such deposition is obtained from 24-hr Tc-99m retention measured with a sensitive counter system. The model is applicable to transport by mucociliary action or by cough, and has been tested in ten normal and ten asthmatic subjects.

Agnew, J.E.; Bateman, J.R.M.; Pavia, D.; Clarke, S.W.

1984-02-01T23:59:59.000Z

24

Improving land-surface model hydrology: Is an explicit aquifer model better than a deeper soil profile?  

E-Print Network [OSTI]

land-surface model hydrology: Is an explicit aquifer modelAL. : LAND-SURFACE MODEL HYDROLOGY Changnon, S. , et al. (land-surface model hydrology: Is an explicit aquifer model

2007-01-01T23:59:59.000Z

25

Risk assessment compatible fire models (RACFMs)  

SciTech Connect (OSTI)

A suite of Probabilistic Risk Assessment Compatible Fire Models (RACFMs) has been developed to represent the hazard posed by a pool fire to weapon systems transported on the B52-H aircraft. These models represent both stand-off (i.e., the weapon system is outside of the flame zone but exposed to the radiant heat load from fire) and fully-engulfing scenarios (i.e., the object is fully covered by flames). The approach taken in developing the RACFMs for both scenarios was to consolidate, reconcile, and apply data and knowledge from all available resources including: data and correlations from the literature, data from an extensive full-scale fire test program at the Naval Air Warfare Center (NAWC) at China Lake, and results from a fire field model (VULCAN). In the past, a single, effective temperature, T{sub f}, was used to represent the fire. The heat flux to an object exposed to a fire was estimated using the relationship for black body radiation, {sigma}T{sub f}{sup 4}. Significant improvements have been made by employing the present approach which accounts for the presence of temperature distributions in fully-engulfing fires, and uses best available correlations to estimate heat fluxes in stand-off scenarios.

Lopez, A.R.; Gritzo, L.A.; Sherman, M.P.

1998-07-01T23:59:59.000Z

26

Gas Migration from Closed Coal Mines to the Surface RISK ASSESSMENT METHODOLOGY AND PREVENTION MEANS  

E-Print Network [OSTI]

Gas Migration from Closed Coal Mines to the Surface RISK ASSESSMENT METHODOLOGY AND PREVENTION to the surface is especially significant in the context of coal mines. This is because mine gas can migrate of the scheduled closure of all coal mining operations in France, INERIS has drawn up, at the request of national

Paris-Sud XI, Université de

27

ESD.864 Modeling and Assessment for Policy, Spring 2011  

E-Print Network [OSTI]

ESD.864 Modeling and Assessment for Policy explores how scientific information and quantitative models can be used to inform policy decision-making. Students will develop an understanding of quantitative modeling techniques ...

Selin, Noelle

28

Eutrophication risk assessment in coastal embayments using simple statistical models  

E-Print Network [OSTI]

Eutrophication risk assessment in coastal embayments using simple statistical models G. Arhonditsis for assessing the risk of eutrophication in marine coastal embayments. The procedure followed of exogenous nutrient loading. Ã? 2003 Elsevier Ltd. All rights reserved. Keywords: Eutrophication; Coastal

Arhonditsis, George B.

29

assessment models risk: Topics by E-print Network  

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

practice in the use of spreadsheets in business. Butler, Raymond J 2008-01-01 13 Eutrophication risk assessment in coastal embayments using simple statistical models...

30

Modeling superconductors using surface impedance techniques  

E-Print Network [OSTI]

This thesis develops a simulation tool that can be used in conjunction with commercially available electromagnetic simulators to model the behavior of superconductors over a wide range of frequencies. This simulation method ...

Aude, Diana Prado Lopes

2010-01-01T23:59:59.000Z

31

Use of OCA and APOLLO in Heliosat-4 method for the assessment of surface downwelling solar irradiance  

E-Print Network [OSTI]

the German Aerospace Center (DLR), for the assessment of surface downwelling solar irradiance (SSI). Each-based assessments of surface downwelling solar irradiance (SSI) are more and more used in the domain of solar energy, diffuse and direct surface irradiance for use in various domains: solar energy, biomass, agriculture

Paris-Sud XI, Université de

32

A Novel Surface Registration Algorithm with Biomedical Modeling Applications  

E-Print Network [OSTI]

1 A Novel Surface Registration Algorithm with Biomedical Modeling Applications Heng Huang, Li Shen and motion. Matheny et al. [2] used 3D Manuscript received October 19, 2005; revised April 17, 2006. Heng: Heng Huang (heng.huang@dartmouth.edu). and 4D surface harmonics to reconstruct rigid and nonrigid

Huang, Heng

33

Modeling Turbulent Hydraulic Fracture Near a Free Surface  

E-Print Network [OSTI]

Modeling Turbulent Hydraulic Fracture Near a Free Surface Victor C. Tsai Seismological Laboratory consider a hydraulic fracture problem in which the crack grows parallel to a free surface, subject to fully components. wall Wall shear stress. ^· Non-dimensionalized ·. 1 Introduction Hydraulic fracture has been

34

Modeling Turbulent Hydraulic Fracture Near a Free Surface  

E-Print Network [OSTI]

Modeling Turbulent Hydraulic Fracture Near a Free Surface Victor C. Tsai Seismological Laboratory consider a hydraulic fracture problem in which the crack grows parallel to a free surface, subject to fully components. ^· Non-dimensionalized ·. 1 Introduction Hydraulic fracture has been studied for many years

35

FIRST PRINCIPLES MODELING FOR LIDAR SENSING OF COMPLEX ICE SURFACES  

E-Print Network [OSTI]

FIRST PRINCIPLES MODELING FOR LIDAR SENSING OF COMPLEX ICE SURFACES J. Kerekes, A. Goodenough, S of monitoring the dynamics and mass balance of glaciers, ice caps, and ice sheets. However, it is also known that ice surfaces can have complex 3-dimensional structure, which can challenge their accurate retrieval

Kerekes, John

36

Assessing the reliability of linear dynamic transformer thermal modelling  

E-Print Network [OSTI]

Assessing the reliability of linear dynamic transformer thermal modelling X. Mao, D.J. Tylavsky and G.A. McCulla Abstract: Improving the utilisation of transformers requires that the hot-spot and top. An alternative method for assessing transformer model reliability is provided. 1 Introduction The maximally

37

Data for surface ionization and complexation modeling  

SciTech Connect (OSTI)

Objective is to compile the thermodynamic data for using the adsorption subroutines in the MINTEQA2 geochemical simulator. As a test of the applicability of the sorption subroutines to UMTRA (Uranium Mill Tailings Remedical Action) project sites, a test case was run using data from Falls City site. Results suggest that adsorption of uranyl ion onto a mixture of silica (quartz) and goethite has limited the mobility of uranium in the groundwater at Falls City. Given the limited analytical data, variability in pH and alkalinity in groundwater, and variation in sorbent phases, the simulations are reasonable (agree within an order of magnitude). Because thermodynamic data exist for relatively few dissolved constituents and their interactions with even fewer mineral phases, the importance of adsorption for hazardous constituent attenuation is difficult to assess. However, the test case indicates that sorption on even two minerals can contribute to U distribution.

Not Available

1990-10-01T23:59:59.000Z

38

ORNL results for Test Case 1 of the International Atomic Energy Agency`s research program on the safety assessment of Near-Surface Radioactive Waste Disposal Facilities  

SciTech Connect (OSTI)

The International Atomic Energy Agency (IAEA) started the Coordinated Research Program entitled ```The Safety Assessment of Near-Surface Radioactive Waste Disposal Facilities.`` The program is aimed at improving the confidence in the modeling results for safety assessments of waste disposal facilities. The program has been given the acronym NSARS (Near-Surface Radioactive Waste Disposal Safety Assessment Reliability Study) for ease of reference. The purpose of this report is to present the ORNL modeling results for the first test case (i.e., Test Case 1) of the IAEA NSARS program. Test Case 1 is based on near-surface disposal of radionuclides that are subsequently leached to a saturated-sand aquifer. Exposure to radionuclides results from use of a well screened in the aquifer and from intrusion into the repository. Two repository concepts were defined in Test Case 1: a simple earth trench and an engineered vault.

Thorne, D.J.; McDowell-Boyer, L.M.; Kocher, D.C.; Little, C.A. [Oak Ridge National Lab., Grand Junction, CO (United States); Roemer, E.K. [Oak Ridge Inst. for Science and Education, TN (United States)

1993-07-01T23:59:59.000Z

39

Modelling the fate of nonylphenolic compounds in1 the Seine River -part 2: assessing the impact of2  

E-Print Network [OSTI]

with the modelling of the global change10 influence on endocrine disruptor concentrations in surface water. Among1 Modelling the fate of nonylphenolic compounds in1 the Seine River - part 2: assessing the impact.09.0299 10 This study aims at modelling the daily concentrations of nonylphenolic compounds such as 4

Boyer, Edmond

40

Assessment of architectural options for surface power generation and energy storage on human Mars missions  

E-Print Network [OSTI]

of the Martian day). Given the significant policy and sustainability advantages of solar power compared-film photovoltaic arrays and energy storage technologies that is anticipated over the coming decades, solar powerAssessment of architectural options for surface power generation and energy storage on human Mars

de Weck, Olivier L.

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


41

Importance of thermal effects and sea surface roughness for offshore wind resource assessment  

E-Print Network [OSTI]

sites. The first large offshore wind farms are currently being built in several countries in EuropeImportance of thermal effects and sea surface roughness for offshore wind resource assessment National Laboratory, Roskilde, Denmark Abstract The economic feasibility of offshore wind power utilisation

Heinemann, Detlev

42

Modeling surface backgrounds from radon progeny plate-out  

SciTech Connect (OSTI)

The next generation low-background detectors operating deep underground aim for unprecedented low levels of radioactive backgrounds. The surface deposition and subsequent implantation of radon progeny in detector materials will be a source of energetic background events. We investigate Monte Carlo and model-based simulations to understand the surface implantation profile of radon progeny. Depending on the material and region of interest of a rare event search, these partial energy depositions can be problematic. Motivated by the use of Ge crystals for the detection of neutrinoless double-beta decay, we wish to understand the detector response of surface backgrounds from radon progeny. We look at the simulation of surface decays using a validated implantation distribution based on nuclear recoils and a realistic surface texture. Results of the simulations and measured ? spectra are presented.

Perumpilly, G.; Guiseppe, V. E.; Snyder, N. [University of South Dakota, Vermillion, South Dakota 57069 (United States)] [University of South Dakota, Vermillion, South Dakota 57069 (United States)

2013-08-08T23:59:59.000Z

43

ASSESSING FRANCE AS A MODEL OF SOCIETAL SUCCESS  

E-Print Network [OSTI]

of this "French model": the French economy being heavily regulated, the well-oiled state tightly controls market crisis," "The French model: Vive la difference!"2 ), and also from free-market minded internationalASSESSING FRANCE AS A MODEL OF SOCIETAL SUCCESS �loi Laurent Sciences-Po Michèle Lamont Harvard

Boyer, Edmond

44

Wind resource assessment with a mesoscale non-hydrostatic model  

E-Print Network [OSTI]

Wind resource assessment with a mesoscale non- hydrostatic model Vincent Guénard, Center for Energy is developed for assessing the wind resource and its uncertainty. The work focuses on an existing wind farm mast measurements. The wind speed and turbulence fields are discussed. It is shown that the k

Boyer, Edmond

45

Dioxins in San Francisco Conceptual Model/Impairment Assessment  

E-Print Network [OSTI]

FINAL Dioxins in San Francisco Bay Conceptual Model/Impairment Assessment Prepared by Mike Connor Partnership November 12, 2004 SFEI Contribution #309 #12;Dioxins in San Francisco Bay: Impairment Assessment. This CM/IA report examines dioxins in San Francisco Bay. Dioxins comprise a group of several hundred

46

Surface tension in the dilute Ising model. The Wulff construction  

E-Print Network [OSTI]

We study the surface tension and the phenomenon of phase coexistence for the Ising model on $\\mathbbm{Z}^d$ ($d \\geqslant 2$) with ferromagnetic but random couplings. We prove the convergence in probability (with respect to random couplings) of surface tension and analyze its large deviations : upper deviations occur at volume order while lower deviations occur at surface order. We study the asymptotics of surface tension at low temperatures and relate the quenched value $\\tau^q$ of surface tension to maximal flows (first passage times if $d = 2$). For a broad class of distributions of the couplings we show that the inequality $\\tau^a \\leqslant \\tau^q$ -- where $\\tau^a$ is the surface tension under the averaged Gibbs measure -- is strict at low temperatures. We also describe the phenomenon of phase coexistence in the dilute Ising model and discuss some of the consequences of the media randomness. All of our results hold as well for the dilute Potts and random cluster models.

Marc Wouts

2008-04-14T23:59:59.000Z

47

Binaural model-based speech intelligibility enhancement and assessment in  

E-Print Network [OSTI]

#12;Binaural model-based speech intelligibility enhancement and assessment in hearing aids beamforming and the effect on binaural cues and speech intelligibility . . . . . . . . . . 31 2.3.4 Cepstral smoothing of masks . . . . . . . . . . . . . . . . . . 35 2.4 Binaural CASA speech

48

Surface photovoltage measurements and finite element modeling of SAW devices.  

SciTech Connect (OSTI)

Over the course of a Summer 2011 internship with the MEMS department of Sandia National Laboratories, work was completed on two major projects. The first and main project of the summer involved taking surface photovoltage measurements for silicon samples, and using these measurements to determine surface recombination velocities and minority carrier diffusion lengths of the materials. The SPV method was used to fill gaps in the knowledge of material parameters that had not been determined successfully by other characterization methods. The second project involved creating a 2D finite element model of a surface acoustic wave device. A basic form of the model with the expected impedance response curve was completed, and the model is ready to be further developed for analysis of MEMS photonic resonator devices.

Donnelly, Christine

2012-03-01T23:59:59.000Z

49

The Whitham Equation as a Model for Surface Water Waves  

E-Print Network [OSTI]

The Whitham equation was proposed as an alternate model equation for the simplified description of uni-directional wave motion at the surface of an inviscid fluid. As the Whitham equation incorporates the full linear dispersion relation of the water wave problem, it is thought to provide a more faithful description of shorter waves of small amplitude than traditional long wave models such as the KdV equation. In this work, we identify a scaling regime in which the Whitham equation can be derived from the Hamiltonian theory of surface water waves. The Whitham equation is integrated numerically, and it is shown that the equation gives a close approximation of inviscid free surface dynamics as described by the Euler equations. The performance of the Whitham equation as a model for free surface dynamics is also compared to two standard free surface models: the KdV and the BBM equation. It is found that in a wide parameter range of amplitudes and wavelengths, the Whitham equation performs on par with or better than both the KdV and BBM equations.

Daulet Moldabayev; Henrik Kalisch; Denys Dutykh

2014-10-30T23:59:59.000Z

50

A finite difference model for free surface gravity drainage  

SciTech Connect (OSTI)

The unconfined gravity flow of liquid with a free surface into a well is a classical well test problem which has not been well understood by either hydrologists or petroleum engineers. Paradigms have led many authors to treat an incompressible flow as compressible flow to justify the delayed yield behavior of a time-drawdown test. A finite-difference model has been developed to simulate the free surface gravity flow of an unconfined single phase, infinitely large reservoir into a well. The model was verified with experimental results in sandbox models in the literature and with classical methods applied to observation wells in the Groundwater literature. The simulator response was also compared with analytical Theis (1935) and Ramey et al. (1989) approaches for wellbore pressure at late producing times. The seepage face in the sandface and the delayed yield behavior were reproduced by the model considering a small liquid compressibility and incompressible porous medium. The potential buildup (recovery) simulated by the model evidenced a different- phenomenon from the drawdown, contrary to statements found in the Groundwater literature. Graphs of buildup potential vs time, buildup seepage face length vs time, and free surface head and sand bottom head radial profiles evidenced that the liquid refills the desaturating cone as a flat moving surface. The late time pseudo radial behavior was only approached after exaggerated long times.

Couri, F.R.; Ramey, H.J. Jr.

1993-09-01T23:59:59.000Z

51

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

E-Print Network [OSTI]

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

Xu, L.

52

Wetting and free surface flow modeling for potting and encapsulation.  

SciTech Connect (OSTI)

As part of an effort to reduce costs and improve quality control in encapsulation and potting processes the Technology Initiative Project ''Defect Free Manufacturing and Assembly'' has completed a computational modeling study of flows representative of those seen in these processes. Flow solutions are obtained using a coupled, finite-element-based, numerical method based on the GOMA/ARIA suite of Sandia flow solvers. The evolution of the free surface is solved with an advanced level set algorithm. This approach incorporates novel methods for representing surface tension and wetting forces that affect the evolution of the free surface. In addition, two commercially available codes, ProCAST and MOLDFLOW, are also used on geometries representing encapsulation processes at the Kansas City Plant. Visual observations of the flow in several geometries are recorded in the laboratory and compared to the models. Wetting properties for the materials in these experiments are measured using a unique flowthrough goniometer.

Brooks, Carlton, F.; Brooks, Michael J. (Los Alamos National Laboratory, Los Alamos, NM); Graham, Alan Lyman (Los Alamos National Laboratory, Los Alamos, NM); Noble, David F. (David Frederick) (.; )); Notz, Patrick K.; Hopkins, Matthew Morgan; Castaneda, Jaime N.; Mahoney, Leo James (Kansas City Plant, Kansas City, MO); Baer, Thomas A.; Berchtold, Kathryn (Los Alamos National Laboratory, Los Alamos, NM); Adolf, Douglas Brian; Wilkes, Edward Dean; Rao, Rekha Ranjana; Givler, Richard C.; Sun, Amy Cha-Tien; Cote, Raymond O.; Mondy, Lisa Ann; Grillet, Anne Mary; Kraynik, Andrew Michael

2007-06-01T23:59:59.000Z

53

THE EFFECT OF SURFACE TENSION IN MODELING INTERFACIAL FRACTURE  

E-Print Network [OSTI]

THE EFFECT OF SURFACE TENSION IN MODELING INTERFACIAL FRACTURE By Tsvetanka Sendova and Jay R Fracture Tsvetanka Sendova and Jay R. Walton Institute for Mathematics and Its Applications, University@math.tamu.edu Abstract. In this article the problem of an interface fracture between two isotropic linear elas- tic

54

Model-based Safety Risk Assessment  

E-Print Network [OSTI]

development life-cycle, in order to identify critical system requirements, such as safety requirements their effectiveness, early in the system development life-cycle, on models derived directly from natural language of functional requirements of arbitrary detail ­ whether it is very early in the life-cycle when functions

Lindsay, Peter

55

E-Print Network 3.0 - assessment modeling approach Sample Search...  

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

OF ENGINEERING CYBERNETICS AND ROBOTICS, 60 Summary: , 60 2009 Sofia Service Oriented Architecture of Assessment Model1 Adelina Aleksieva... Assessment Model. To achieve...

56

E-Print Network 3.0 - assessing local model Sample Search Results  

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

OF ENGINEERING CYBERNETICS AND ROBOTICS, 60 Summary: , 60 2009 Sofia Service Oriented Architecture of Assessment Model1 Adelina Aleksieva... Assessment Model. To achieve...

57

Modeling for Free Surface Flow with Phase Change  

SciTech Connect (OSTI)

The development of predictive capability for free surface flow with phase change is essential to evaluate liquid wall protection schemes for various fusion chambers in IFE and MFE. This paper presents a numerical methodology for free surface flow with heat and mass transfer to help resolve feasibility issues encountered in the aforementioned fusion engineering fields. The numerical methodology is conducted within the framework of the incompressible flow with the heat and mass transfer model. We present a new second-order projection method, in conjunction with Approximate-Factorization techniques (AF method) for incompressible Navier-Stokes equations. The level set method was used to capture the free surface of the flow and the deformation of the droplets accurately. This numerical investigation identifies the physics characterizing transient heat and mass transfer of the droplet and the free surface flow. The preliminary results show that the numerical methodology is successful in modeling the free surface with heat and mass transfer, though some severe deformation such as breaking and merging occurs. The versatility of the numerical methodology shows that the work can easily handle complex physical conditions in fusion science and engineering.

Luo Xiaoyong; Ni Mingjiu; Ying, Alice; Abdou, M. [University of California, Los Angeles (United States)

2005-05-15T23:59:59.000Z

58

Models of the solvent-accessible surface of biopolymers  

SciTech Connect (OSTI)

Many biopolymers such as proteins, DNA, and RNA have been studied because they have important biomedical roles and may be good targets for therapeutic action in treating diseases. This report describes how plastic models of the solvent-accessible surface of biopolymers were made. Computer files containing sets of triangles were calculated, then used on a stereolithography machine to make the models. Small (2 in.) models were made to test whether the computer calculations were done correctly. Also, files of the type (.stl) required by any ISO 9001 rapid prototyping machine were written onto a CD-ROM for distribution to American companies.

Smith, R.E.

1996-09-01T23:59:59.000Z

59

Model and Analytic Processes for Export License Assessments  

SciTech Connect (OSTI)

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

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

2011-09-29T23:59:59.000Z

60

Assessment of circuit board surface finishes for electronic assembly with lead-free solders  

SciTech Connect (OSTI)

The suitability of various metallic printed wiring board surface finishes was assessed for new technology applications that incorporate assembly with Lead-free solders. The manufacture of a lead-free product necessitates elimination of lead (Pb) from the solder, the circuit board as well as the component lead termination. It is critical however for the selected interconnect Pb-free solder and the corresponding printed wiring board (PWB) and component lead finishes to be mutually compatible. Baseline compatibility of select Pb-free solders with Pb containing PWB surface finish and components was assessed. This was followed by examining the compatibility of the commercially available CASTIN{trademark} (SnAgCuSb) Pb-free solder with a series of PWB metallic finishes: Ni/Au, Ni/Pd, and Pd/Cu. The compatibility was assessed with respect to assembly performance, solder joint integrity and long term attachment reliability. Solder joint integrity and mechanical behavior of representative 50 mil pitch 20I/O SOICs was determined before and after thermal stress. Mechanical pull test studies demonstrated that the strength of SnAgCuSb solder interconnections is notably greater than that of SnPb interconnections.

Ray, U.; Artaki, I.; Finley, D.W.; Wenger, G.M. [Bell Labs., Princeton, NJ (United States). Lucent Technologies; Pan, T.; Blair, H.D.; Nicholson, J.M. [Ford Motor Co., Dearborn, MI (United States); Vianco, P.T. [Sandia National Labs., Albuquerque, NM (United States)

1996-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" 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

Microfriction studies of model self-lubricating surfaces  

SciTech Connect (OSTI)

Self-lubricating composites consist of at least one structural (matrix) phase and at least one phase to provide lubrication. Modeling the behavior of such composites involves ascertaining the frictional contributions of each constituent phase under varying conditions of lubricating films coverage. The ORNL friction microprobe (FMP), a specialized microcontact tribometer, was used to investigate the frictional behavior of both matrix and lubricant phases to support the development of self-lubricating, surfaces. Polished CVD-silicon carbide deposits and silicon wafers were used as substrates. The wafers were intended to simulate the thin silica films present on SiC surfaces at elevated temperature. Molybdenum disulfide, in both sputtered and burnished forms, was used as the model lubricant. The effects of CVD-SiC substrate surface roughness and method of lubricant film deposition on the substrate were studied for single passes of a spherical silicon nitride slider (NBD 200 material). In contrast to the smooth sliding exhibit by burnished, films, sputtered MoS{sub 2} surfaces exhibited marked stick-slip behavior, indicating that the frictional behavior of solid lubricating coatings can be quite erratic on a microscale, especially when asperity contacts are elastically compliant.

Blau, P.J.; Yust, C.S. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.

1993-05-06T23:59:59.000Z

62

Bayesian Model Averaging in Proportional Hazard Models: Assessing the Risk of a Stroke  

E-Print Network [OSTI]

Bayesian Model Averaging in Proportional Hazard Models: Assessing the Risk of a Stroke Chris T In the context of the Cardiovascular Health Study, a comprehensive investigation into the risk factors for stroke of assessing who is at high risk for stroke. 1 Introduction Stroke is the third leading cause of death among

Volinsky, Chris

63

A comparison of land surface model soil hydraulic properties estimated by inverse modeling and  

E-Print Network [OSTI]

of water in the soil. This in turn plays an important role in the water and energy cycles at the land depths in the soil column controls the partitioning of two key energy fluxes of concern in climate modelsA comparison of land surface model soil hydraulic properties estimated by inverse modeling

Small, Eric

64

Final Report DE-EE0005380: Assessment of Offshore Wind Farm Effects on Sea Surface, Subsurface and Airborne Electronic Systems  

SciTech Connect (OSTI)

Offshore wind energy is a valuable resource that can provide a significant boost to the US renewable energy portfolio. A current constraint to the development of offshore wind farms is the potential for interference to be caused by large wind farms on existing electronic and acoustical equipment such as radar and sonar systems for surveillance, navigation and communications. The US Department of Energy funded this study as an objective assessment of possible interference to various types of equipment operating in the marine environment where offshore wind farms could be installed. The objective of this project was to conduct a baseline evaluation of electromagnetic and acoustical challenges to sea surface, subsurface and airborne electronic systems presented by offshore wind farms. To accomplish this goal, the following tasks were carried out: (1) survey electronic systems that can potentially be impacted by large offshore wind farms, and identify impact assessment studies and research and development activities both within and outside the US, (2) engage key stakeholders to identify their possible concerns and operating requirements, (3) conduct first-principle modeling on the interactions of electromagnetic signals with, and the radiation of underwater acoustic signals from, offshore wind farms to evaluate the effect of such interactions on electronic systems, and (4) provide impact assessments, recommend mitigation methods, prioritize future research directions, and disseminate project findings. This report provides a detailed description of the methodologies used to carry out the study, key findings of the study, and a list of recommendations derived based the findings.

Ling, Hao [The University of Texas at Austin] [The University of Texas at Austin; Hamilton, Mark F. [The University of Texas at Austin Applied Research Laboratories] [The University of Texas at Austin Applied Research Laboratories; Bhalla, Rajan [Science Applications International Corporation] [Science Applications International Corporation; Brown, Walter E. [The University of Texas at Austin Applied Research Laboratories] [The University of Texas at Austin Applied Research Laboratories; Hay, Todd A. [The University of Texas at Austin Applied Research Laboratories] [The University of Texas at Austin Applied Research Laboratories; Whitelonis, Nicholas J. [The University of Texas at Austin] [The University of Texas at Austin; Yang, Shang-Te [The University of Texas at Austin] [The University of Texas at Austin; Naqvi, Aale R. [The University of Texas at Austin] [The University of Texas at Austin

2013-09-30T23:59:59.000Z

65

Assessing streamaquifer interactions through inverse modeling of flow routing q  

E-Print Network [OSTI]

Assessing stream­aquifer interactions through inverse modeling of flow routing q Jozsef Szilagyi a and Nieber, 1977; Troch et al., 1993; Brutsaert and Lopez, 1998; Szilagyi et al., 1998; Par- lange et al., 2001; Szilagyi, 2003a). Knowledge of this inter- action between streamflow and groundwater during flood

Szilagyi, Jozsef

66

Multi-attribute Model for Assessment of SMEs adoption of  

E-Print Network [OSTI]

Multi-attribute Model for Assessment of SMEs adoption of High Performance Computing Cloud Services boosters for SMEs, particularly manufacturing. · Huge amount of and $ are currently being spent on simulation experiments through various initiatives. #12;Introduction · Technology adoptance is in its early

Bohanec, Marko

67

Groundwater Impacts of Radioactive Wastes and Associated Environmental Modeling Assessment  

SciTech Connect (OSTI)

This article provides a review of the major sources of radioactive wastes and their impacts on groundwater contamination. The review discusses the major biogeochemical processes that control the transport and fate of radionuclide contaminants in groundwater, and describe the evolution of mathematical models designed to simulate and assess the transport and transformation of radionuclides in groundwater.

Ma, Rui; Zheng, Chunmiao; Liu, Chongxuan

2012-11-01T23:59:59.000Z

68

New Near-Infrared Surface Brightness Fluctuation Models  

E-Print Network [OSTI]

We present new theoretical models for surface brightness fluctuations in the near-infrared. We show the time evolution of near-infrared brightness fluctuation properties over large age and metallicity ranges, i.e., from 12 Myr to 16 Gyr, and from Z/Zsun=1/50 to Z/Zsun=2.5, for single age, single metallicity stellar populations. All the stellar models are followed from the zero age main sequence to the central carbon ignition for massive stars, or to the end of the thermally pulsing regime of the asymptotic giant branch phase for low and intermediate mass stars. The new models are compared with observed near-infrared fluctuation absolute magnitudes and colours for a sample of Magellanic Cloud star clusters and Fornax Cluster galaxies. For star clusters younger than ~3 Gyr, the predicted near-infrared fluctuation properties are in a satisfactory agreement with observed ones over a wide range of stellar population metallicities. However, for older star clusters, the agreement between the observed and predicted near-IR brightness fluctuations depends on how the surface brightness absolute magnitudes are estimated. The computed set of models are not able to match the observed near-IR fluctuation absolute magnitudes and colours simultaneously. We argue that the observed discrepancies between the predicted and observed properties of old MC superclusters are more likely due to observational reasons.

M. Mouhcine; R. A. Gonzalez; M. C. Liu

2005-11-30T23:59:59.000Z

69

Radionuclide release rates from spent fuel for performance assessment modeling  

SciTech Connect (OSTI)

In a scenario of aqueous transport from a high-level radioactive waste repository, the concentration of radionuclides in water in contact with the waste constitutes the source term for transport models, and as such represents a fundamental component of all performance assessment models. Many laboratory experiments have been done to characterize release rates and understand processes influencing radionuclide release rates from irradiated nuclear fuel. Natural analogues of these waste forms have been studied to obtain information regarding the long-term stability of potential waste forms in complex natural systems. This information from diverse sources must be brought together to develop and defend methods used to define source terms for performance assessment models. In this manuscript examples of measures of radionuclide release rates from spent nuclear fuel or analogues of nuclear fuel are presented. Each example represents a very different approach to obtaining a numerical measure and each has its limitations. There is no way to obtain an unambiguous measure of this or any parameter used in performance assessment codes for evaluating the effects of processes operative over many millennia. The examples are intended to suggest by example that in the absence of the ability to evaluate accuracy and precision, consistency of a broadly based set of data can be used as circumstantial evidence to defend the choice of parameters used in performance assessments.

Curtis, D.B.

1994-11-01T23:59:59.000Z

70

Fuel cycle assessment: A compendium of models, methodologies, and approaches  

SciTech Connect (OSTI)

The purpose of this document is to profile analytical tools and methods which could be used in a total fuel cycle analysis. The information in this document provides a significant step towards: (1) Characterizing the stages of the fuel cycle. (2) Identifying relevant impacts which can feasibly be evaluated quantitatively or qualitatively. (3) Identifying and reviewing other activities that have been conducted to perform a fuel cycle assessment or some component thereof. (4) Reviewing the successes/deficiencies and opportunities/constraints of previous activities. (5) Identifying methods and modeling techniques/tools that are available, tested and could be used for a fuel cycle assessment.

Not Available

1994-07-01T23:59:59.000Z

71

Annual report, October 1980-September 1981 Multimedia radionuclide exposure assessment modeling.  

SciTech Connect (OSTI)

Pacific Northwest Laboratory (PNL) and Los Alamos National Laboratory (LANL) are jointly developing a methodology for assessing exposures of the air, water, and plants to radionuclides as part of an overall development effort of a radionuclide disposal site evaluation methodology. Work in FY-1981 continued the development of the Multimedia Contaminant Environmental Exposure Assessment (MCEA) methodology and initiated an assessment of radionuclide migration in Los Alamos and Pueblo Canyons, New Mexico, using the methodology. The AIRTRAN model was completed, briefly tested, and documented. In addition, a literature search for existing validation data for AIRTRAN was performed. The feasibility and advisability of including the UNSAT moisture flow model as a submodel of the terrestrial code BIOTRAN was assessed. A preliminary application of the proposed MCEA methodology, as it related to the Mortandad-South Mortandad Canyon site in New Mexico is discussed. This preliminary application represented a scaled-down version of the methodology in which only the terrestrial, overland, and surface water components were used. An update describing the progress in the assessment of radionuclide migration in Los Alamos and Pueblo Canyons is presented. 38 references, 47 figures, 11 tables.

Whelan, G.; Onishi, Y.; Simmons, C.S.; Horst, T.W.; Gupta, S.K.; Orgill, M.M.; Newbill, C.A.

1982-12-01T23:59:59.000Z

72

Solar Resource Assessment: Databases, Measurements, Models, and Information Sources (Fact Sheet)  

SciTech Connect (OSTI)

Fact sheet for Solar Resource Assessment Workshop, Denver CO, Oct 29, 2008: ?Solar Resource Assessment Databases, Measurements, Models, and Information Sources

Not Available

2008-10-01T23:59:59.000Z

73

Replication of surface features from a master model to an amorphous metallic article  

DOE Patents [OSTI]

The surface features of an article are replicated by preparing a master model having a preselected surface feature thereon which is to be replicated, and replicating the preselected surface feature of the master model. The replication is accomplished by providing a piece of a bulk-solidifying amorphous metallic alloy, contacting the piece of the bulk-solidifying amorphous metallic alloy to the surface of the master model at an elevated replication temperature to transfer a negative copy of the preselected surface feature of the master model to the piece, and separating the piece having the negative copy of the preselected surface feature from the master model.

Johnson, William L. (Pasadena, CA); Bakke, Eric (Murrieta, CA); Peker, Atakan (Aliso Viejo, CA)

1999-01-01T23:59:59.000Z

74

Surfaces  

E-Print Network [OSTI]

Surfaces is a collection of four individual essays which focus on the characteristics and tactile qualities of surfaces within a variety of perceived landscapes. Each essay concentrates on a unique surface theme and purpose; ...

DeMaio, Ernest Vincent, 1964-

1989-01-01T23:59:59.000Z

75

Probing protein orientation near charged surfaces with an implicit-solvent model and the PyGBe code  

E-Print Network [OSTI]

Protein-surface interactions are ubiquitous in biological processes and bioengineering, yet are not fully understood. In the field of biosensors, a key factor in biosensor performance is the orientation of biomolecules near charged surfaces. The aim of this work is developing and assessing a computational model to study proteins interacting with charged surfaces and obtain orientation data. After extending the implicit-solvent model used in the open-source code PyGBe and deriving an analytical solution for simple geometry, our careful grid-convergence analysis builds confidence on the correctness and value of our approach for probing protein orientation. Further computational experiments support it: they study preferred orientations for protein GB1 D4' and immunoglobulin G. Sampling the free energy for protein GB1 at a range of tilt and rotation angles with respect to the charged surface, we calculated the probability of the protein orientation and observed a dipolar behavior. This result is consistent with p...

Cooper, Christopher D

2015-01-01T23:59:59.000Z

76

Literature Review and Assessment of Plant and Animal Transfer Factors Used in Performance Assessment Modeling  

SciTech Connect (OSTI)

A literature review and assessment was conducted by Pacific Northwest National Laboratory (PNNL) to update information on plant and animal radionuclide transfer factors used in performance-assessment modeling. A group of 15 radionuclides was included in this review and assessment. The review is composed of four main sections, not including the Introduction. Section 2.0 provides a review of the critically important issue of physicochemical speciation and geochemistry of the radionuclides in natural soil-water systems as it relates to the bioavailability of the radionuclides. Section 3.0 provides an updated review of the parameters of importance in the uptake of radionuclides by plants, including root uptake via the soil-groundwater system and foliar uptake due to overhead irrigation. Section 3.0 also provides a compilation of concentration ratios (CRs) for soil-to-plant uptake for the 15 selected radionuclides. Section 4.0 provides an updated review on radionuclide uptake data for animal products related to absorption, homeostatic control, approach to equilibration, chemical and physical form, diet, and age. Compiled transfer coefficients are provided for cow’s milk, sheep’s milk, goat’s milk, beef, goat meat, pork, poultry, and eggs. Section 5.0 discusses the use of transfer coefficients in soil, plant, and animal modeling using regulatory models for evaluating radioactive waste disposal or decommissioned sites. Each section makes specific suggestions for future research in its area.

Robertson, David E.; Cataldo, Dominic A.; Napier, Bruce A.; Krupka, Kenneth M.; Sasser, Lyle B.

2003-07-20T23:59:59.000Z

77

The Paradoxes of Military Risk Assessment: Will the Enterprise Risk Assessment Model, Composite Risk Management and Associated  

E-Print Network [OSTI]

to assess the nation's military preparedness. However, risk management is not a panacea for the problemsThe Paradoxes of Military Risk Assessment: Will the Enterprise Risk Assessment Model, Composite Risk Management and Associated Techniques Provide the Predicted Benefits? Chris. W. Johnson, Glasgow

Johnson, Chris

78

Modeling issues associated with production reactor safety assessment  

SciTech Connect (OSTI)

This paper describes several Probabilistic Safety Assessment (PSA) modeling issues that are related to the unique design and operation of the production reactors. The identification of initiating events and determination of a set of success criteria for the production reactors is of concern because of their unique design. The modeling of accident recovery must take into account the unique operation of these reactors. Finally, a more thorough search and evaluation of common-cause events is required to account for combinations of unique design features and operation that might otherwise not be included in the PSA. It is expected that most of these modeling issues also would be encountered when modeling some of the other more unique reactor and nonreactor facilities that are part of the DOE nuclear materials production complex. 9 refs., 2 figs.

Stack, D.W. (Los Alamos National Lab., NM (USA)); Thomas, W.R. (Science and Engineering Associates, Inc., Albuquerque, NM (USA))

1990-01-01T23:59:59.000Z

79

Assessment of damage to the desert surfaces of Kuwait due to the Gulf War  

SciTech Connect (OSTI)

This is a preliminary report on a joint research project by Boston University and the Kuwait Institute for Scientific Research that commenced in April 1992. The project aim is to establish the extent and nature of environmental damage to the desert surface and coastal zone of Kuwait due to the Gulf War and its aftermath. Change detection image enhancement techniques were employed to enhance environmental change by comparison of Landsat Thematic Mapper images obtained before the wars and after the cessation of the oil and well fires. Higher resolution SPOT images were also utilized to evaluate the nature of the environmental damage to specific areas. The most prominent changes were due to: (1) the deposition of oil and course-grained soot on the desert surface as a result of oil rain'' from the plume that emanated from the oil well fires; (2) the formation of hundreds of oil lakes, from oil seepage at the damaged oil well heads; (3) the mobilization of sand and dust and (4) the pollution of segments of the coastal zone by the deposition of oil from several oil spills. Interpretation of satellite image data are checked in the field to confirm the observations, and to assess the nature of the damage. Final results will be utilized in establishing the needs for remedial action to counteract the harmful effects of the various types of damage to the environment of Kuwait.

El-Baz, F. (Boston Univ., MA (United States). Center for Remote Sensing); Al-Ajmi, D. (Kuwait Inst. for Scientific Research (Kuwait). Environmental and Earth Sciences Div.)

1993-01-01T23:59:59.000Z

80

Surface water drainage system. Environmental assessment and finding of no significant impact  

SciTech Connect (OSTI)

This Environmental Assessment (EA) is written pursuant to the National Environmental Policy Act (NEPA). The document identifies and evaluates the action proposed to correct deficiencies in, and then to maintain, the surface water drainage system serving the Department of Energy`s Rocky Flats Environmental Technology Site (Site), located north of Golden, Colorado. Many of the activities proposed would not normally be subject to this level of NEPA documentation. However, in many cases, maintenance of the system has been deferred to the point that wetlands vegetation has become established in some ditches and culverts, creating wetlands. The proposed activities would damage or remove some of these wetlands in order to return the drainage system to the point that it would be able to fully serve its intended function - stormwater control. The Department of Energy (DOE) regulations require that activities affecting environmentally sensitive areas like wetlands be the subject of an EA. Most portions of the surface water drainage system are presently inadequate to convey the runoff from a 100-year storm event. As a result, such an event would cause flooding across much of the Site and possibly threaten the integrity of the dams at the terminal ponds. Severe flooding would not only cause damage to facilities and equipment, but could also facilitate the transport of contaminants from individual hazardous substance sites (IHSSs). Uncontrolled flow through the A- and B-series ponds could cause contaminated sediments to become suspended and carried downstream. Additionally, high velocity flood flows significantly increase erosion losses.

NONE

1996-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" 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

Improved Formulations for Air-Surface Exchanges Related to National Security Needs: Dry Deposition Models  

SciTech Connect (OSTI)

The Department of Homeland Security and others rely on results from atmospheric dispersion models for threat evaluation, event management, and post-event analyses. The ability to simulate dry deposition rates is a crucial part of our emergency preparedness capabilities. Deposited materials pose potential hazards from radioactive shine, inhalation, and ingestion pathways. A reliable characterization of these potential exposures is critical for management and mitigation of these hazards. A review of the current status of dry deposition formulations used in these atmospheric dispersion models was conducted. The formulations for dry deposition of particulate materials from am event such as a radiological attack involving a Radiological Detonation Device (RDD) is considered. The results of this effort are applicable to current emergency preparedness capabilities such as are deployed in the Interagency Modeling and Atmospheric Assessment Center (IMAAC), other similar national/regional emergency response systems, and standalone emergency response models. The review concludes that dry deposition formulations need to consider the full range of particle sizes including: 1) the accumulation mode range (0.1 to 1 micron diameter) and its minimum in deposition velocity, 2) smaller particles (less than .01 micron diameter) deposited mainly by molecular diffusion, 3) 10 to 50 micron diameter particles deposited mainly by impaction and gravitational settling, and 4) larger particles (greater than 100 micron diameter) deposited mainly by gravitational settling. The effects of the local turbulence intensity, particle characteristics, and surface element properties must also be addressed in the formulations. Specific areas for improvements in the dry deposition formulations are 1) capability of simulating near-field dry deposition patterns, 2) capability of addressing the full range of potential particle properties, 3) incorporation of particle surface retention/rebound processes, and. 4) development of dry deposition formulations applicable to urban areas. Also to improve dry deposition modeling capabilities, atmospheric dispersion models in which the dry deposition formulations are imbedded need better source-term plume initialization and improved in-plume treatment of particle growth processes. Dry deposition formulations used in current models are largely inapplicable to the complex urban environment. An improved capability is urgently needed to provide surface-specific information to assess local exposure hazard levels in both urban and non-urban areas on roads, buildings, crops, rivers, etc. A model improvement plan is developed with a near-term and far-term component. Despite some conceptual limitations, the current formulations for particle deposition based on a resistance approach have proven to provide reasonable dry deposition simulations. For many models with inadequate dry deposition formulations, adding or improving a resistance approach will be the desirable near-term update. Resistance models however are inapplicable aerodynamically very rough surfaces such as urban areas. In the longer term an improved parameterization of dry deposition needs to be developed that will be applicable to all surfaces, and in particular urban surfaces.

Droppo, James G.

2006-07-01T23:59:59.000Z

82

A Physically Based Runoff Routing Model for Land Surface and Earth System Models  

SciTech Connect (OSTI)

A new physically based runoff routing model, called the Model for Scale Adaptive River Transport (MOSART), has been developed to be applicable across local, regional, and global scales. Within each spatial unit, surface runoff is first routed across hillslopes and then discharged along with subsurface runoff into a ‘‘tributary subnetwork’’ before entering the main channel. The spatial units are thus linked via routing through the main channel network, which is constructed in a scale-consistent way across different spatial resolutions. All model parameters are physically based, and only a small subset requires calibration.MOSART has been applied to the Columbia River basin at 1/ 168, 1/ 88, 1/ 48, and 1/ 28 spatial resolutions and was evaluated using naturalized or observed streamflow at a number of gauge stations. MOSART is compared to two other routing models widely used with land surface models, the River Transport Model (RTM) in the Community Land Model (CLM) and the Lohmann routing model, included as a postprocessor in the Variable Infiltration Capacity (VIC) model package, yielding consistent performance at multiple resolutions. MOSART is further evaluated using the channel velocities derived from field measurements or a hydraulic model at various locations and is shown to be capable of producing the seasonal variation and magnitude of channel velocities reasonably well at different resolutions. Moreover, the impacts of spatial resolution on model simulations are systematically examined at local and regional scales. Finally, the limitations ofMOSART and future directions for improvements are discussed.

Li, Hongyi; Wigmosta, Mark S.; Wu, Huan; Huang, Maoyi; Ke, Yinghai; Coleman, Andre M.; Leung, Lai-Yung R.

2013-06-13T23:59:59.000Z

83

Test Plan to Assess Fire Effects on the Function of an Engineered Surface Barrier  

SciTech Connect (OSTI)

Wildfire is a frequent perturbation in shrub steppe ecosystems, altering the flora, fauna, atmosphere, and soil of these systems. Research on the fire effects has focused mostly on natural ecosystems with essentially no attention on engineered systems like surface barriers. The scope of the project is to use a simulated wildfire to induce changes in an engineered surface barrier and document the effects on barrier performance. The main objective is to quantify the effects of burning and the resulting post-fire conditions on alterations in soil physical properties; hydrologic response, particularly the water balance; geochemical properties; and biological properties. A secondary objective is to use the lessons learned to maximize fire protection in the design of long-term monitoring systems based on electronic sensors. A simulated wildfire will be initiated, controlled and monitored at the 200-BP-1 barrier in collaboration with the Hanford Fire Department during the fall of 2008. The north half of the barrier will be divided into nine 12 x 12 m plots, each of which will be randomly assigned a fuel load of 2 kg m-2 or 4 kg m-2. Each plot will be ignited around the perimeter and flames allowed to carry to the centre. Any remaining unburned vegetation will be manually burned off using a drip torch. Progress of the fire and its effects will be monitored using point measurements of thermal, hydrologic, and biotic variables. Three measures of fire intensity will be used to characterize fire behavior: (1) flame height, (2) the maximum temperature at three vertical profile levels, and (3) total duration of elevated temperature at these levels. Pre-burn plant information, including species diversity, plant height, and canopy diameter will be measured on shrubs from the plots to be burned and from control plots at the McGee ranch. General assessments of shrub survival, recovery, and recruitment will be made after the fire. Near-surface soil samples will be collected pre- and post-burn to determine changes in the gravel content of the surface layer so as to quantify inflationary or deflationary responses to fire and to reveal the ability of the surface to resist post-fire erosive stresses. Measures of bulk density, water repellency, water retention, and hydraulic conductivity will be used to characterize changes in infiltration rates and water storage capacity following the fire. Samples will also be analyzed to quantify geochemical changes including changes in soil pH, cation exchange capacity, specific surface area, and the concentration of macro nutrients (e.g. N, P, K) and other elements such as Na, Mg, Ca, that are critical to the post-fire recovery revegetation. Soil CO2 emissions will be measured monthly for one year following the burn to document post-fire stimulation of carbon turnover and soil biogenic emissions. Surface and subsurface temperature measurements at and near monitoring installations will be used to document fire effects on electronic equipment. The results of this study will be used to bridge the gaps in knowledge on the effects of fire on engineered ecosystems (e.g. surface barriers), particularly the hydrologic and biotic characteristics that govern the water and energy balance. These results will also support the development of practical fire management techniques for barriers that are compatible with wildfire suppression strategies. Furthermore, lessons learned will be use to develop installation strategies needed to protect electronic monitoring equipment from the intense heat of fire and the potential damaging effects of smoke and fire extinguishing agents. Such information is needed to better understand long-term barrier performance under extreme conditions, especially if site maintenance and operational funding is lost for activities such as barrier revegetation.

Ward, Anderson L.; Berlin, Gregory T.; Cammann, Jerry W.; Leary, Kevin D.; Link, Steven O.

2008-09-29T23:59:59.000Z

84

CliCrop: a Crop Water-Stress and Irrigation Demand Model for an Integrated Global Assessment Model Approach  

E-Print Network [OSTI]

This paper describes the use of the CliCrop model in the context of climate change general assessment

Fant, C.A.

85

A Hydro-Economic Approach to Representing Water Resources Impacts in Integrated Assessment Models  

SciTech Connect (OSTI)

Grant Number DE-FG02-98ER62665 Office of Energy Research of the U.S. Department of Energy Abstract Many Integrated Assessment Models (IAM) divide the world into a small number of highly aggregated regions. Non-OECD countries are aggregated geographically into continental and multiple-continental regions or economically by development level. Current research suggests that these large scale aggregations cannot accurately represent potential water resources-related climate change impacts. In addition, IAMs do not explicitly model the flow regulation impacts of reservoir and ground water systems, the economics of water supply, or the demand for water in economic activities. Using the International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT) model of the International Food Policy Research Institute (IFPRI) as a case study, this research implemented a set of methodologies to provide accurate representation of water resource climate change impacts in Integrated Assessment Models. There were also detailed examinations of key issues related to aggregated modeling including: modeling water consumption versus water withdrawals; ground and surface water interactions; development of reservoir cost curves; modeling of surface areas of aggregated reservoirs for estimating evaporation losses; and evaluating the importance of spatial scale in river basin modeling. The major findings include: - Continental or national or even large scale river basin aggregation of water supplies and demands do not accurately capture the impacts of climate change in the water and agricultural sector in IAMs. - Fortunately, there now exist gridden approaches (0.5 X 0.5 degrees) to model streamflows in a global analysis. The gridded approach to hydrologic modeling allows flexibility in aligning basin boundaries with national boundaries. This combined with GIS tools, high speed computers, and the growing availability of socio-economic gridded data bases allows assignment of demands to river basins to create hydro-economic zones that respect as much as possible both political and hydrologic integrity in different models. - To minimize pre-processing of data and add increased flexibility to modeling water resources and uses, it is recommended that water withdrawal demands be modeled, not consumptive requirements even though this makes the IAM more complex. - IAMs must consider changes in water availability for irrigation under climate change; ignoring them is more inaccurate than ignoring yield changes in crops under climate change. - Determining water availability and cost in river basins must include modeling streamflows, reservoirs and their operations, and ground water and its interaction with surface water. - Scale issues are important. The results from condensing demands and supplies in a large complex river basin to one node can be misleading for all uses under low flow conditions and instream flow uses under all conditions. Monthly is generally the most accurate scale for modeling river flows and demands. Challenges remain in integrating hydrologic units with political boundaries but the gridded approach to hydrologic modeling allows flexibility in aligning basin boundaries with political boundaries. - Using minimal reservoir cost data, it is possible to use basin topography to estimate reservoir storage costs. - Reservoir evaporation must be considered when assessing the usable water in a watershed. Several methods are available to estimate the relationship between aggregated storage surface area and storage volume. - For existing or future IAMs that can not use the appropriate aggregation for water, a water preprocessor may be required due the finer scale of hydrologic impacts.

Kirshen, Paul H.; Strzepek, Kenneth, M.

2004-01-14T23:59:59.000Z

86

An international land-biosphere model benchmarking activity for the IPCC Fifth Assessment Report (AR5)  

SciTech Connect (OSTI)

The need to capture important climate feedbacks in general circulation models (GCMs) has resulted in efforts to include atmospheric chemistry and land and ocean biogeochemistry into the next generation of production climate models, called Earth System Models (ESMs). While many terrestrial and ocean carbon models have been coupled to GCMs, recent work has shown that such models can yield a wide range of results (Friedlingstein et al., 2006). This work suggests that a more rigorous set of global offline and partially coupled experiments, along with detailed analyses of processes and comparisons with measurements, are needed. The Carbon-Land Model Intercomparison Project (C-LAMP) was designed to meet this need by providing a simulation protocol and model performance metrics based upon comparisons against best-available satellite- and ground-based measurements (Hoffman et al., 2007). Recently, a similar effort in Europe, called the International Land Model Benchmark (ILAMB) Project, was begun to assess the performance of European land surface models. These two projects will now serve as prototypes for a proposed international land-biosphere model benchmarking activity for those models participating in the IPCC Fifth Assessment Report (AR5). Initially used for model validation for terrestrial biogeochemistry models in the NCAR Community Land Model (CLM), C-LAMP incorporates a simulation protocol for both offline and partially coupled simulations using a prescribed historical trajectory of atmospheric CO2 concentrations. Models are confronted with data through comparisons against AmeriFlux site measurements, MODIS satellite observations, NOAA Globalview flask records, TRANSCOM inversions, and Free Air CO2 Enrichment (FACE) site measurements. Both sets of experiments have been performed using two different terrestrial biogeochemistry modules coupled to the CLM version 3 in the Community Climate System Model version 3 (CCSM3): the CASA model of Fung, et al., and the carbon-nitrogen (CN) model of Thornton. Comparisons of the CLM3 offline results against observational datasets have been performed and are described in Randerson et al. (2009). CLM version 4 has been evaluated using C-LAMP, showing improvement in many of the metrics. Efforts are now underway to initiate a Nitrogen-Land Model Intercomparison Project (N-LAMP) to better constrain the effects of the nitrogen cycle in biosphere models. Presented will be new results from C-LAMP for CLM4, initial N-LAMP developments, and the proposed land-biosphere model benchmarking activity.

Hoffman, Forrest M [ORNL; Randerson, James T [ORNL; Thornton, Peter E [ORNL; Bonan, Gordon [National Center for Atmospheric Research (NCAR); Erickson III, David J [ORNL; Fung, Inez [University of California, Berkeley

2009-12-01T23:59:59.000Z

87

Facet Model and Mathematical Morphology for Surface Characterization  

SciTech Connect (OSTI)

This paper describes an algorithm for the automatic segmentation and representation of surface structures and non-uniformities in an industrial setting. The automatic image processing and analysis algorithm is developed as part of a complete on-line web characterization system of a papermaking process at the wet end. The goal is to: (1) link certain types of structures on the surface of the web to known machine parameter values, and (2) find the connection between detected structures at the beginning of the line and defects seen on the final product. Images of the pulp mixture (slurry), carried by a fast moving table, are obtained using a stroboscopic light and a CCD camera. This characterization algorithm succeeded where conventional contrast and edge detection techniques failed due to a poorly controlled environment. The images obtained have poor contrast and contain noise caused by a variety of sources. After a number of enhancement steps, conventional segmentation methods still f ailed to detect any structures and are consequently discarded. Techniques tried include the Canny edge detector, the Sobel, Roberts, and Prewitt's filters, as well as zero crossings. The facet model algorithm, is then applied to the images with various parameter settings and is found to be successful in detecting the various topographic characteristics of the surface of the slurry. Pertinent topographic elements are retained and a filtered image computed. Carefully tailored morphological operators are then applied to detect and segment regions of interest. Those regions are then selected according to their size, elongation, and orientation. Their bounding rectangles are computed and represented. Also addressed in this paper are aspects of the real time implementation of this algorithm for on-line use. The algorithm is tested on over 500 images of slurry and is found to segment and characterize nonuniformities on all 500 images.

Abidi, B.R.; Goddard, J.S.; Hunt, M.A.; Sari-Sarraf, H.

1999-11-13T23:59:59.000Z

88

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

SciTech Connect (OSTI)

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

Niyogi, Devdutta S. [Purdue

2013-06-07T23:59:59.000Z

89

Review of free-surface MHD experiments and modeling.  

SciTech Connect (OSTI)

This review paper was prepared to survey the present status of analytical and experimental work in the area of free surface MHD and thus provide a well informed starting point for further work by the Advanced Limiter-diverter Plasma-facing Systems (ALPS) program. ALPS were initiated to evaluate the potential for improved performance and lifetime for plasma-facing systems. The main goal of the program is to demonstrate the advantages of advanced limiter/diverter systems over conventional systems in terms of power density capability, component lifetime, and power conversion efficiency, while providing for safe operation and minimizing impurity concerns for the plasma. Most of the work to date has been applied to free surface liquids. A multi-disciplinary team from several institutions has been organized to address the key issues associated with these systems. The main performance goals for advanced limiters and diverters are a peak heat flux of >50 MW/m{sup 2}, elimination of a lifetime limit for erosion, and the ability to extract useful heat at high power conversion efficiency ({approximately}40%). The evaluation of various options is being conducted through a combination of laboratory experiments, modeling of key processes, and conceptual design studies.

Molokov, S.; Reed, C. B.

2000-06-02T23:59:59.000Z

90

Methods for Developing Emissions Scenarios for Integrated Assessment Models  

SciTech Connect (OSTI)

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

Prinn, Ronald [MIT; Webster, Mort [MIT

2007-08-20T23:59:59.000Z

91

Examining emissions policy issues with an integrated assessment model  

SciTech Connect (OSTI)

In the policy analysis process of asking ``What if'' questions, there is considerable advantage in the analyst being able to address the questions directly rather than sending the questions to scientists in particular disciplines and awaiting answers. Obviously the former option is likely to produce speedier results than the latter; in addition, the questions can be easily modified as the issues change or become more focused. The primary potential shortcoming of an analyst addressing questions that may be beyond his or her particular expertise is that the policy analyst may not understand the limitations of the analysis. Here the author briefly describes a peer-reviewed integrated assessment model that can be exercised within minutes in a desktop environment, discuss some of the advantages and limitations of the approach, and exercise portions of the model to compare with observations. Because of the nature of the conference at which this paper is being presented, the discussion focuses on the air pollution modeling components of the integrated assessment.

Shannon, J. D.

1999-10-21T23:59:59.000Z

92

HVAC Modeling for Cost of Ownership Assessment in Biotechnology & Drugs Manufacturing  

E-Print Network [OSTI]

2000 Broomes, Peter. , “HVAC Modeling for Cost of Ownership2000 Broomes, Peter. , “HVAC Results Comparison”, April,HVAC Modeling for Cost of Ownership Assessment in

Broomes, Peter; Dornfeld, David A

2003-01-01T23:59:59.000Z

93

Water Research 38 (2004) 33313339 Testing a surface tension-based model to predict the salting  

E-Print Network [OSTI]

Water Research 38 (2004) 3331­3339 Testing a surface tension-based model to predict the salting out associated with transferring solutes from water to a salt solution to the difference in surface tensions likely reflects the inability of the simple surface tension model to account for all interactions among

Herbert, Bruce

94

SURFACE TENSION AND WULFF SHAPE FOR A LATTICE MODEL WITHOUT SPIN FLIP SYMMETRY  

E-Print Network [OSTI]

SURFACE TENSION AND WULFF SHAPE FOR A LATTICE MODEL WITHOUT SPIN FLIP SYMMETRY T. BODINEAU AND E. PRESUTTI Abstract. We propose a new definition of surface tension and check it in a spin model on the phase transitions line and prove: (i) existence of the surface tension in the thermodynamic limit

95

Why are climate models reproducing the observed global surface warming so well?  

E-Print Network [OSTI]

Why are climate models reproducing the observed global surface warming so well? Reto Knutti1 global surface warming so well?, Geophys. Res. Lett., 35, L18704, doi:10.1029/ 2008GL034932. 1 models reproduce the observed surface warming better than one would expect given the uncertainties

Fischlin, Andreas

96

Western oil-shale development: a technology assessment. Volume 4. Solid waste from mining and surface retorts  

SciTech Connect (OSTI)

The overall objectives of this study were to: review and evaluate published information on the disposal, composition, and leachability of solid wastes produced by aboveground shale oil extraction processes; examine the relationship of development to surface and groundwater quality in the Piceance Creek basin of northwestern Colorado; and identify key areas of research necessary to quantitative assessment of impact. Information is presented under the following section headings: proposed surface retorting developments; surface retorting processes; environmental concerns; chemical/mineralogical composition of raw and retorted oil shale; disposal procedures; water quality; and research needs.

Not Available

1982-01-01T23:59:59.000Z

97

Assessment of skill and portability in regional marine biogeochemical models: Role of multiple planktonic groups  

E-Print Network [OSTI]

radiation, and wind stress in a model simulation of the sea surface temperature seasonally cycle in the tropical Pacific Ocean,

2007-01-01T23:59:59.000Z

98

Assessment of Heliosat-4 surface solar irradiance derived on the basis of SEVIRI-APOLLO cloud products  

E-Print Network [OSTI]

high spatial and temporal resolutions, the APOLLO product is suitable for use in solar energy as their spectral distribution for the uses in various domains: solar energy, biomass, agriculture, human healthAssessment of Heliosat-4 surface solar irradiance derived on the basis of SEVIRI-APOLLO cloud

Boyer, Edmond

99

Modeling the Near-Surface Using High-Resolution Seismic Data  

E-Print Network [OSTI]

In the Arabian Peninsula, the near-surface represents a major challenge in seismic exploration. For accurate deep subsurface reservoir imaging, an accurate near-surface velocity model is required. In this dissertation, I ...

Al-Zayer, Ramzy Mohammed

2010-01-26T23:59:59.000Z

100

THE PENA BLANCA NATURAL ANALOGUE PERFORMANCE ASSESSMENT MODEL  

SciTech Connect (OSTI)

The Nopal I uranium mine in the Sierra Pena Blanca, Chihuahua, Mexico serves as a natural analogue to the Yucca Mountain repository. The Pena Blanca Natural Analogue Performance Assessment Model simulates the mobilization and transport of radionuclides that are released from the mine and transported to the saturated zone. The Pena Blanca Natural Analogue Performance Assessment Model uses probabilistic simulations of hydrogeologic processes that are analogous to the processes that occur at the Yucca Mountain site. The Nopal I uranium deposit lies in fractured, welded, and altered rhyolitic ash-flow tuffs that overlie carbonate rocks, a setting analogous to the geologic formations at the Yucca Mountain site. The Nopal I mine site has the following analogous characteristics as compared to the Yucca Mountain repository site: (1) Analogous source--UO{sub 2} uranium ore deposit = spent nuclear fuel in the repository; (2) Analogous geology--(i.e. fractured, welded, and altered rhyolitic ash-flow tuffs); (3) Analogous climate--Semiarid to arid; (4) Analogous setting--Volcanic tuffs overlie carbonate rocks; and (5) Analogous geochemistry--Oxidizing conditions Analogous hydrogeology: The ore deposit lies in the unsaturated zone above the water table.

G. Saulnier and W. Statham

2006-04-16T23:59:59.000Z

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101

Model Evaluation and Hindcasting: An Experiment with an Integrated Assessment Model  

SciTech Connect (OSTI)

Integrated assessment models have been extensively used for analyzing long term energy and greenhouse emissions trajectories and have influenced key policies on this subject. Though admittedly these models are focused on the long term trajectories, how well these models are able to capture historical dynamics is an open question. In a first experiment of its kind, we present a framework for evaluation of such integrated assessment models. We use Global Change Assessment Model for this zero order experiment, and focus on the building sector results for USA. We calibrate the model for 1990 and run it forward up to 2095 in five year time steps. This gives us results for 1995, 2000, 2005 and 2010 which we compare to observed historical data at both fuel level and service level. We focus on bringing out the key insights for the wider process of model evaluation through our experiment with GCAM. We begin with highlighting that creation of an evaluation dataset and identification of key evaluation metric is the foremost challenge in the evaluation process. Our analysis highlights that estimation of functional form of the relationship between energy service demand, which is an unobserved variable, and its drivers is a significant challenge in the absence of adequate historical data for both the dependent and driver variables. Historical data availability for key metrics is a serious limiting factor in the process of evaluation. Interestingly, service level data against which such models need to be evaluated are itself a result of models. Thus for energy services, the best we can do is compare our model results with other model results rather than observed and measured data. We show that long term models, by the nature of their construction, will most likely underestimate the rapid growth in some services observed in a short time span. Also, we learn that modeling saturated energy services like space heating is easier than modeling unsaturated services like space cooling and understanding that how far a service is from its saturation level is a key question which we probably don’t have an answer to. Finally and most importantly, even if long term models partially miss the short term dynamics, the long term insights provides by these models is fairly robust. We conclude by highlighting that our work is the first step in the much wider process of integrated assessment model evaluation and will hence have its own limitations. Future evaluation research work should build upon this zero order experiment for improving our modeling of human and coupled earth systems.

Chaturvedi, Vaibhav; Kim, Son H.; Smith, Steven J.; Clarke, Leon E.; Zhou, Yuyu; Kyle, G. Page; Patel, Pralit L.

2013-11-01T23:59:59.000Z

102

Discrete Fracture Network Models for Risk Assessment of Carbon Sequestration in Coal  

SciTech Connect (OSTI)

A software package called DFNModeler has been developed to assess the potential risks associated with carbon sequestration in coal. Natural fractures provide the principal conduits for fluid flow in coal-bearing strata, and these fractures present the most tangible risks for the leakage of injected carbon dioxide. The objectives of this study were to develop discrete fracture network (DFN) modeling tools for risk assessment and to use these tools to assess risks in the Black Warrior Basin of Alabama, where coal-bearing strata have high potential for carbon sequestration and enhanced coalbed methane recovery. DFNModeler provides a user-friendly interface for the construction, visualization, and analysis of DFN models. DFNModeler employs an OpenGL graphics engine that enables real-time manipulation of DFN models. Analytical capabilities in DFNModeler include display of structural and hydrologic parameters, compartmentalization analysis, and fluid pathways analysis. DFN models can be exported to third-party software packages for flow modeling. DFN models were constructed to simulate fracturing in coal-bearing strata of the upper Pottsville Formation in the Black Warrior Basin. Outcrops and wireline cores were used to characterize fracture systems, which include joint systems, cleat systems, and fault-related shear fractures. DFN models were constructed to simulate jointing, cleating, faulting, and hydraulic fracturing. Analysis of DFN models indicates that strata-bound jointing compartmentalizes the Pottsville hydrologic system and helps protect shallow aquifers from injection operations at reservoir depth. Analysis of fault zones, however, suggests that faulting can facilitate cross-formational flow. For this reason, faults should be avoided when siting injection wells. DFN-based flow models constructed in TOUGH2 indicate that fracture aperture and connectivity are critical variables affecting the leakage of injected CO{sub 2} from coal. Highly transmissive joints near an injection well have potential to divert a large percentage of an injected CO{sub 2} stream away from a target coal seam. However, the strata-bound nature of Pottsville fracture systems is a natural factor that mitigates the risk of long-range leakage and surface seepage. Flow models indicate that cross-formational flow in strata-bound joint networks is low and is dissipated by about an order of magnitude at each successive bedding contact. These models help confirm that strata-bound joint networks are self-compartmentalizing and that the thick successions of interbedded shale and sandstone separating the Pottsville coal zones are confining units that protect shallow aquifers from injection operations at reservoir depth. DFN models are powerful tools for the simulation and analysis of fracture networks and can play an important role in the assessment of risks associated with carbon sequestration and enhanced coalbed methane recovery. Importantly, the stochastic nature DFN models dictates that they cannot be used to precisely reproduce reservoir conditions in a specific field area. Rather, these models are most useful for simulating the fundamental geometric and statistical properties of fracture networks. Because the specifics of fracture architecture in a given area can be uncertain, multiple realizations of DFN models and DFN-based flow models can help define variability that may be encountered during field operations. Using this type of approach, modelers can inform the risk assessment process by characterizing the types and variability of fracture architecture that may exist in geologic carbon sinks containing natural fractures.

Jack Pashin; Guohai Jin; Chunmiao Zheng; Song Chen; Marcella McIntyre

2008-07-01T23:59:59.000Z

103

Model Test Setup and Program for Experimental Estimation of Surface Loads of the SSG Kvitsy  

E-Print Network [OSTI]

Model Test Setup and Program for Experimental Estimation of Surface Loads of the SSG Kvitsøy Pilot Engineering No. 32 ISSN: 1603-9874 Model Test Setup and Program for Experimental Estimation of Surface Loads University October, 2005 #12;#12;Preface This report presents the preparations done prior to model tests

104

Interfaces and Free Boundaries, 4 : 2002, 7188 A TOTALVARIATION SURFACE ENERGY MODEL FOR THIN FILMS OF  

E-Print Network [OSTI]

Interfaces and Free Boundaries, 4 : 2002, 71­88 A TOTAL­VARIATION SURFACE ENERGY MODEL FOR THIN to model the energy on surfaces separating regions of di#erent variants. We find that the deformation energy modeled by # ## h |# 2 u| 2 dx, where # is a small positive strain­gradient coe#cient,# h

Luskin, Mitchell

105

A simulation model of focus and radial servos in Compact Disc players with Disc surface defects  

E-Print Network [OSTI]

A simulation model of focus and radial servos in Compact Disc players with Disc surface defects P of controllers handling surface defects easier. A simulation model of Compact Disc players playing discs of the controller has been based on trial and error on real test systems since no simulation models of the defects

Wickerhauser, M. Victor

106

Surface Tension Adjustment in a Pseudo-Potential Lattice Boltzmann Model  

E-Print Network [OSTI]

Pseudo-potential lattice Boltzmann models have been widely applied in many multiphase simulations. However, most of these models still suffer from some drawbacks such as spurious velocities and untunable surface tension. In this paper, we aim to discuss the surface tension of a popular pseudo-potential model proposed by Kupershtokh et al., which has attracted much attention due to its simplicity and stability. The influence of a parameter on the surface tension in the model is analyzed. Based on the analysis, we proposed a method to adjust surface tension by changing the parameter in the model. However, the density distribution and the stability of the model also depend on the parameter. To adjust the surface tension independently, the pressure tensor modifying method is introduced and numerically tested. The simulation results show that, by applying the pressure tensor modifying method, the surface tension can be adjusted with little influence on the stability and density distributions.

Hu, Anjie; Uddin, Rizwan

2014-01-01T23:59:59.000Z

107

Tumor Tracking Method Based on a Deformable 4D CT Breathing Motion Model Driven by an External Surface Surrogate  

SciTech Connect (OSTI)

Purpose: To develop a tumor tracking method based on a surrogate-driven motion model, which provides noninvasive dynamic localization of extracranial targets for the compensation of respiration-induced intrafraction motion in high-precision radiation therapy. Methods and Materials: The proposed approach is based on a patient-specific breathing motion model, derived a priori from 4-dimensional planning computed tomography (CT) images. Model parameters (respiratory baseline, amplitude, and phase) are retrieved and updated at each treatment fraction according to in-room radiography acquisition and optical surface imaging. The baseline parameter is adapted to the interfraction variations obtained from the daily cone beam (CB) CT scan. The respiratory amplitude and phase are extracted from an external breathing surrogate, estimated from the displacement of the patient thoracoabdominal surface, acquired with a noninvasive surface imaging device. The developed method was tested on a database of 7 lung cancer patients, including the synchronized information on internal and external respiratory motion during a CBCT scan. Results: About 30 seconds of simultaneous acquisition of CBCT and optical surface images were analyzed for each patient. The tumor trajectories identified in CBCT projections were used as reference and compared with the target trajectories estimated from surface displacement with the a priori motion model. The resulting absolute differences between the reference and estimated tumor motion along the 2 image dimensions ranged between 0.7 and 2.4 mm; the measured phase shifts did not exceed 7% of the breathing cycle length. Conclusions: We investigated a tumor tracking method that integrates breathing motion information provided by the 4-dimensional planning CT with surface imaging at the time of treatment, representing an alternative approach to point-based external–internal correlation models. Although an in-room radiograph-based assessment of the reliability of the motion model is envisaged, the developed technique does not involve the estimation and continuous update of correlation parameters, thus requiring a less intense use of invasive imaging.

Fassi, Aurora, E-mail: aurora.fassi@mail.polimi.it [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Schaerer, Joël; Fernandes, Mathieu [CREATIS, CNRS UMR 5220, INSERM U1044, Université Lyon 1, INSA-Lyon, Villeurbanne (France); Department of Radiotherapy, Centre Léon Bérard, Lyon (France); Riboldi, Marco [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Bioengineering Unit, CNAO Foundation, Pavia (Italy); Sarrut, David [CREATIS, CNRS UMR 5220, INSERM U1044, Université Lyon 1, INSA-Lyon, Villeurbanne (France); Department of Radiotherapy, Centre Léon Bérard, Lyon (France); Baroni, Guido [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Bioengineering Unit, CNAO Foundation, Pavia (Italy)

2014-01-01T23:59:59.000Z

108

A next-generation modeling capability assesses wind turbine array fluid dynamics and aeroelastic simulations  

E-Print Network [OSTI]

A next-generation modeling capability assesses wind turbine array fluid dynamics and aeroelastic of multi-megawatt turbines requires a new generation of modeling capability to assess individual turbine. Key Result The work is generating several models, including actuator line models of several wind

109

Surface tension model for surfactant solutions at the critical micelle concentration  

E-Print Network [OSTI]

A model for the limiting surface tension of surfactant solutions (surface tension at and above the critical micelle concentration, cmc) was developed. This model takes advantage of the equilibrium between the surfactant molecules on the liquid/vacuum surface and in micelles in the bulk at the cmc. An approximate analytical equation for the surface tension at the cmc was obtained. The derived equation contains two parameters, which characterize the intermolecular interactions in the micelles, and the third parameter, which is the surface area per surfactant molecule at the interface. These parameters were calculated using a new atomistic modeling approach. The performed calculations of the limiting surface tension for four simple surfactants show good agreement with experimental data (~30% accuracy). The developed model provides the guidance for design of surfactants with low surface tension values.

S. F. Burlatsky; V. V. Atrazhev; D. V. Dmitriev; V. I. Sultanov; E. N. Timokhina; E. A. Ugolkova; S. Tulyani; A. Vincitore

2013-06-19T23:59:59.000Z

110

Multiobjective calibration and sensitivity of a distributed land surface water and energy balance model  

E-Print Network [OSTI]

identification and energy balance models on a tallgrassdata for surface energy balance evaluation of a semiaridWatershed. We are energy balance components over a semiarid

Houser, Paul R; Gupta, Hoshin V; Shuttleworth, W. James; Famiglietti, James S

2001-01-01T23:59:59.000Z

111

Models for source term, flow, transport and dose assessment in NRC`s Iterative Performance Assessment, Phase 2  

SciTech Connect (OSTI)

The core consequence modules for the recently completed Phase 2 Iterative Performance Assessment (IPA) of the Yucca Mountain repository for high-level nuclear waste depend on models for releases from the engineered barrier system (source term), flow of liquid and gas, transport of radionuclides in the geosphere and assessment of dose to target populations. The source term model includes temperature and moisture phenomena in the near-field environment, general, pitting and crevice corrosion, contact of the waste form by water, dissolution and oxidation of the waste form, and transport of dissolved and gaseous radionuclides from the waste package by advection and diffusion. The liquid flow and transport models describe water flow through fractures and matrix in both the unsaturated and saturated zones. Models for flow of gas and transport of {sup 14}CO{sub 2} released from the engineered barrier system to the atmosphere take into account repository heat and the geothermal gradient. The dose assessment model calculates doses to a regional population and a farm family for an assumed reference biosphere in the vicinity of the repository. The Phase 2 IPA led to a number of suggestions for model improvement: (1) improve the ability of the models to include spatial and temporal variability in the parameters; (2) improve the coupling among processes, especially the effects of changing environments in the waste packages; (3) develop more mechanistic models, but abstracted for use in total system performance assessment; and (4) use more site specific parameters, especially for the dose assessments.

McCartin, T.; Codell, R.; Neel, R.; Ford, W.; Wescott, R.; Bradbury, J. [Nuclear Regulatory Commission, Washington, DC (United States); Sagar, B.; Walton, J. [Center for Nuclear Waste Regulatory Analyses, San Antonio, TX (United States)

1994-12-31T23:59:59.000Z

112

Inverse Modeling of Hydrologic Parameters Using Surface Flux and Runoff Observations in the Community Land Model  

SciTech Connect (OSTI)

This study demonstrates the possibility of inverting hydrologic parameters using surface flux and runoff observations in version 4 of the Community Land Model (CLM4). Previous studies showed that surface flux and runoff calculations are sensitive to major hydrologic parameters in CLM4 over different watersheds, and illustrated the necessity and possibility of parameter calibration. Two inversion strategies, the deterministic least-square fitting and stochastic Markov-Chain Monte-Carlo (MCMC) - Bayesian inversion approaches, are evaluated by applying them to CLM4 at selected sites. The unknowns to be estimated include surface and subsurface runoff generation parameters and vadose zone soil water parameters. We find that using model parameters calibrated by the least-square fitting provides little improvements in the model simulations but the sampling-based stochastic inversion approaches are consistent - as more information comes in, the predictive intervals of the calibrated parameters become narrower and the misfits between the calculated and observed responses decrease. In general, parameters that are identified to be significant through sensitivity analyses and statistical tests are better calibrated than those with weak or nonlinear impacts on flux or runoff observations. Temporal resolution of observations has larger impacts on the results of inverse modeling using heat flux data than runoff data. Soil and vegetation cover have important impacts on parameter sensitivities, leading to the different patterns of posterior distributions of parameters at different sites. Overall, the MCMC-Bayesian inversion approach effectively and reliably improves the simulation of CLM under different climates and environmental conditions. Bayesian model averaging of the posterior estimates with different reference acceptance probabilities can smooth the posterior distribution and provide more reliable parameter estimates, but at the expense of wider uncertainty bounds.

Sun, Yu; Hou, Zhangshuan; Huang, Maoyi; Tian, Fuqiang; Leung, Lai-Yung R.

2013-12-10T23:59:59.000Z

113

A continuous surface tension force formulation for diffuse-interface models  

E-Print Network [OSTI]

A continuous surface tension force formulation for diffuse-interface models Junseok Kim October 2004 Available online 30 November 2004 Abstract We present a new surface tension force formulation field because pressure includes the gradient terms resulting from the modified surface tension term

Frey, Pascal

114

hal00272925, SURFACE TENSION IN THE DILUTE ISING MODEL. THE WULFF  

E-Print Network [OSTI]

hal­00272925, version 1 ­ 14 Apr 2008 SURFACE TENSION IN THE DILUTE ISING MODEL. THE WULFF CONSTRUCTION. MARC WOUTS Abstract. We study the surface tension and the phenomenon of phase coexistence in probability (with respect to random couplings) of surface tension and analyze its large deviations : upper

Paris-Sud XI, Université de

115

Surface Free Energies, Interfacial Tensions and Correlation Lengths of the ABF Models  

E-Print Network [OSTI]

Surface Free Energies, Interfacial Tensions and Correlation Lengths of the ABF Models David L. O. Abstract The surface free energies, interfacial tensions and correlation lengths of the Andrews been established there are various quan- tities of physical interest, such as the surface free energies

Pearce, Paul A.

116

Modeling hydrogen and helium entrapment in flowing liquid metal surfaces as plasma-facing components in  

E-Print Network [OSTI]

Modeling hydrogen and helium entrapment in flowing liquid metal surfaces as plasma the PFC surface (helium and hydrogen isotopes) while accommodating high heat loads. To study this problem rather than requiring a standard vacuum system. Hydrogen isotope (DT) particles that strike the surface

Harilal, S. S.

117

A Formal Model for A System's Attack Surface Pratyusa K. Manadhata Dilsun K. Kaynar  

E-Print Network [OSTI]

A Formal Model for A System's Attack Surface Pratyusa K. Manadhata Dilsun K. Kaynar Jeannette M software [18]. In this paper, we propose to use a software system's attack surface measurement as an indicator of the system's security; the larger the attack surface, the more insecure the system. We

Wing, Jeannette M.

118

Molecular modelling and simulation of the surface tension of real quadrupolar fluids  

E-Print Network [OSTI]

Molecular modelling and simulation of the surface tension of fluids with force fields is discussed. 29 real fluids are studied, including nitrogen, oxygen, carbon dioxide, carbon monoxide, fluorine, chlorine, bromine, iodine, ethane, ethylene, acetylene, propyne, propylene, propadiene, carbon disulfide, sulfur hexafluoride, and many refrigerants. The fluids are represented by two-centre Lennard-Jones plus point quadrupole models from the literature. These models were adjusted only to experimental data of the vapour pressure and saturated liquid density so that the results for the surface tension are predictions. The deviations between the predictions and experimental data for the surface tension are of the order of 20 percent. The surface tension is usually overestimated by the models. For further improvements, data on the surface tension can be included in the model development. A suitable strategy for this is multi-criteria optimization based on Pareto sets. This is demonstrated using the model for carbon dioxide as an example.

Stephan Werth; Katrin Stöbener; Peter Klein; Karl-Heinz Küfer; Martin Horsch; Hans Hasse

2014-08-21T23:59:59.000Z

119

Molecular modelling and simulation of the surface tension of real quadrupolar fluids  

E-Print Network [OSTI]

Molecular modelling and simulation of the surface tension of fluids with force fields is discussed. 29 real fluids are studied, including nitrogen, oxygen, carbon dioxide, carbon monoxide, fluorine, chlorine, bromine, iodine, ethane, ethylene, acetylene, propyne, propylene, propadiene, carbon disulfide, sulfur hexafluoride, and many refrigerants. The fluids are represented by two-centre Lennard-Jones plus point quadrupole models from the literature. These models were adjusted only to experimental data of the vapour pressure and saturated liquid density so that the results for the surface tension are predictions. The deviations between the predictions and experimental data for the surface tension are of the order of 20 percent. The surface tension is usually overestimated by the models. For further improvements, data on the surface tension can be included in the model development. A suitable strategy for this is multi-criteria optimization based on Pareto sets. This is demonstrated using the model for carbon d...

Werth, Stephan; Klein, Peter; Küfer, Karl-Heinz; Horsch, Martin; Hasse, Hans

2014-01-01T23:59:59.000Z

120

Safety Assessment for a Surface Repository in the Chernobyl Exclusion Zone - Methodology for Assessing Disposal under Intervention Conditions - 13476  

SciTech Connect (OSTI)

The Radioactive Waste Disposal Facility (RWDF) Buryakovka was constructed in 1986 as part of the intervention measures after the accident at Chernobyl NPP (ChNPP). Today, RWDF Buryakovka is still being operated but its maximum capacity is nearly reached. Plans for enlargement of the facility exist since more than 10 years but have not been implemented yet. In the framework of an European Commission Project DBE Technology GmbH prepared a safety analysis report of the facility in its current state (SAR) and a preliminary safety analysis report (PSAR) based on the planned enlargement. Due to its history RWDF Buryakovka does not fully comply with today's best international practices and the latest Ukrainian regulations in this area. The most critical aspects are its inventory of long-lived radionuclides, and the non-existent multi-barrier waste confinement system. A significant part of the project was dedicated, therefore, to the development of a methodology for the safety assessment taking into consideration the facility's special situation and to reach an agreement with all stakeholders involved in the later review and approval procedure of the safety analysis reports. Main aspect of the agreed methodology was to analyze the safety, not strictly based on regulatory requirements but on the assessment of the actual situation of the facility including its location within the Exclusion Zone. For both safety analysis reports, SAR and PSAR, the assessment of the long-term safety led to results that were either within regulatory limits or within the limits allowing for a specific situational evaluation by the regulator. (authors)

Haverkamp, B.; Krone, J. [DBE TECHNOLOGY GmbH, Eschenstr. 55, D-31224 Peine (Germany)] [DBE TECHNOLOGY GmbH, Eschenstr. 55, D-31224 Peine (Germany); Shybetskyi, I. [Radioenvironmental Centre at Presidium of National Academy of Sciences of Ukraine, Ul. O. Gonchara 55 b, 01054 Kiev (Ukraine)] [Radioenvironmental Centre at Presidium of National Academy of Sciences of Ukraine, Ul. O. Gonchara 55 b, 01054 Kiev (Ukraine)

2013-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" 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

Modeling of solar thermal selective surfaces and thermoelectric generators  

E-Print Network [OSTI]

A thermoelectric generator is a solid-state device that converts a heat flux into electrical power via the Seebeck effect. When a thermoelectric generator is inserted between a solar-absorbing surface and a heat sink, a ...

McEnaney, Kenneth

2010-01-01T23:59:59.000Z

122

Tradespace model for planetary surface exploration hopping vehicles  

E-Print Network [OSTI]

Robotic planetary surface exploration, which has greatly benefited humankind's scientific knowledge of the solar system, has to date been conducted by sedentary landers or by slow, terrain-limited rovers. However, there ...

Cunio, Phillip M

2012-01-01T23:59:59.000Z

123

Galerkin method to model thin free surface flows  

E-Print Network [OSTI]

Viscoelastic thin films with free surface are important in industry as well as in nature. However, there does not exist a robust and systematic framework to analyze such films. Lubrication approximations, largely successful ...

Lee. Sungyon

2007-01-01T23:59:59.000Z

124

Triangle geometry processing for surface modeling and cartesian grid generation  

DOE Patents [OSTI]

Cartesian mesh generation is accomplished for component based geometries, by intersecting components subject to mesh generation to extract wetted surfaces with a geometry engine using adaptive precision arithmetic in a system which automatically breaks ties with respect to geometric degeneracies. During volume mesh generation, intersected surface triangulations are received to enable mesh generation with cell division of an initially coarse grid. The hexagonal cells are resolved, preserving the ability to directionally divide cells which are locally well aligned.

Aftosmis, Michael J. (San Mateo, CA) [San Mateo, CA; Melton, John E. (Hollister, CA) [Hollister, CA; Berger, Marsha J. (New York, NY) [New York, NY

2002-09-03T23:59:59.000Z

125

IEEE TRANSACTION ON VISUALIZATION AND COMPUTER GRAPHICS 1 Water Surface Modeling from A Single  

E-Print Network [OSTI]

water brings unique challenges [15]. Major difficulties include it- s lack of matchable featuresIEEE TRANSACTION ON VISUALIZATION AND COMPUTER GRAPHICS 1 Water Surface Modeling from A Single and Phillip Willis Abstract--We introduce a video based approach for producing water surface models. Recent

Martin, Ralph R.

126

Spatio-Temporal Modelling of Near-Surface Ocean Winds  

E-Print Network [OSTI]

Introduction Motivation Data Part I: Dynamical Model State-Space Model Kalman Filter Assimilation Algorithm contour map from the Wave Assimilation Model overlaid with satellite mea- surements. #12;Forecasts Overlaid With Satellite Measurements General wave height contour map from the Wave Assimilation Model

Malmberg, Anders

127

Screening model for nanowire surface-charge sensors in liquid  

E-Print Network [OSTI]

The conductance change of nanowire field-effect transistors is considered a highly sensitive probe for surface charge. However, Debye screening of relevant physiological liquid environments challenge device performance due to competing screening from the ionic liquid and nanowire charge carriers. We discuss this effect within Thomas-Fermi and Debye-Huckel theory and derive analytical results for cylindrical wires which can be used to estimate the sensitivity of nanowire surface-charge sensors. We study the interplay between the nanowire radius, the Thomas-Fermi and Debye screening lengths, and the length of the functionalization molecules. The analytical results are compared to finite-element calculations on a realistic geometry.

Martin H. Sorensen; Niels Asger Mortensen; Mads Brandbyge

2007-08-17T23:59:59.000Z

128

3D Statistical Models for Tooth Surface Reconstruction  

E-Print Network [OSTI]

, orthodontists regularly employ plaster casts of the patient's dentition, also known as study models. These plaster models are used to prepare treatment plans and for making accurate measurements. However

Boyer, Edmond

129

Multilayer Perceptron Error Surfaces: Visualization, Structure and Modelling  

E-Print Network [OSTI]

. This is commonly formulated as a multivariate non­linear optimization problem over a very high­dimensional space of analysis are not well­suited to this problem. Visualizing and describ­ ing the error surface are also three related methods. Firstly, Principal Component Analysis (PCA) is proposed as a method

Gallagher, Marcus

130

Multi-layer Perceptron Error Surfaces: Visualization, Structure and Modelling  

E-Print Network [OSTI]

. This is commonly formulated as a multivariate non-linear optimization problem over a very high-dimensional space of analysis are not well-suited to this problem. Visualizing and describ- ing the error surface are also three related methods. Firstly, Principal Component Analysis (PCA) is proposed as a method

Gallagher, Marcus

131

AN URBAN SURFACE EXCHANGE PARAMETERISATION FOR MESOSCALE MODELS  

E-Print Network [OSTI]

boundary layer, Urban climato- logy, Urban energy balance. 1. Introduction The main reason floor) and vertical (walls) surfaces on the wind speed, temperature and turbulent kinetic energy in a bidimensional case of a city over flat terrain. The new parameterisation is shown to be able to reproduce

132

Automated Software Engineering Process Assessment: Supporting Diverse Models using an Ontology  

E-Print Network [OSTI]

, ISO 9001). It also provides an in-the-loop automated process assessment capability that can help, ISO 9001), and suitable performance and scalability. The approach can reduce the effort required assessment while simultaneously supporting diverse process assessment reference models (CMMI, ISO/IEC 15504

Ulm, Universität

133

Modelling of Stochastic Hybrid Systems with Applications to Accident Risk Assessment  

E-Print Network [OSTI]

Modelling of Stochastic Hybrid Systems with Applications to Accident Risk Assessment #12;The SYSTEMS WITH APPLICATIONS TO ACCIDENT RISK ASSESSMENT DISSERTATION to obtain the doctor's degree promotor Prof. dr. A. Bagchi #12;Contents 1 Introduction 3 1.1 Accident risk assessment

Del Moral , Pierre

134

Probing protein orientation near charged surfaces with an implicit-solvent model and the PyGBe code  

E-Print Network [OSTI]

Protein-surface interactions are ubiquitous in biological processes and bioengineering, yet are not fully understood. In the field of biosensors, a key factor in biosensor performance is the orientation of biomolecules near charged surfaces. The aim of this work is developing and assessing a computational model to study proteins interacting with charged surfaces and obtain orientation data. After extending the implicit-solvent model used in the open-source code PyGBe and deriving an analytical solution for simple geometry, our careful grid-convergence analysis builds confidence on the correctness and value of our approach for probing protein orientation. Further computational experiments support it: they study preferred orientations for protein GB1 D4' and immunoglobulin G. Sampling the free energy for protein GB1 at a range of tilt and rotation angles with respect to the charged surface, we calculated the probability of the protein orientation and observed a dipolar behavior. This result is consistent with published molecular-dynamics simulations and experimental studies using this protein. The case of immunoglobulin G is more challenging due to the large size of the molecule, but it is also more relevant to biosensor technology. The probability distribution of orientations for this protein at varying surface charge and salt concentration suggests that it is easier to control the antibody orientation with low salt concentration and high surface charge. The results also show that local interactions dominate over dipole moment for this protein. In view of its capacity to deal with much larger biomolecules than direct simulation, this implicit-solvent model can offer a valuable approach in biosensor studies.

Christopher D. Cooper; Lorena A. Barba

2015-03-31T23:59:59.000Z

135

Integrated Assessment Modeling of Carbon Sequestration and Land Use Emissions Using Detailed Model Results and Observations  

SciTech Connect (OSTI)

This report outlines the progress on the development and application of Integrated Assessment Modeling of Carbon Sequestrations and Land Use Emissions supported by the DOE Office of Biological and Environmental Research (OBER), U.S. Department of Energy, Grant No. DOE-DE-FG02-01ER63069. The overall objective of this collaborative project between the University of Illinois at Urbana-Champaign (UIUC), Oak Ridge National Laboratory (ORNL), Lawrence Livermore National Laboratory (LLNL), and Pacific Northwest National Laboratory (PNNL) was to unite the latest advances in carbon cycle research with scientifically based models and policy-related integrated assessment tools that incorporate computationally efficient representations of the latest knowledge concerning science and emission trajectories, and their policy implications. As part of this research we accomplished the following tasks that we originally proposed: (1) In coordination with LLNL and ORNL, we enhanced the Integrated Science Assessment Model's (ISAM) parametric representation of the ocean and terrestrial carbon cycles that better represent spatial and seasonal variations, which are important to study the mechanisms that influence carbon sequestration in the ocean and terrestrial ecosystems; (2) Using the MiniCAM modeling capability, we revised the SRES (IPCC Special Report on Emission Scenarios; IPCC, 2000) land use emission scenarios; and (3) On the application front, the enhanced version of ISAM modeling capability is applied to understand how short- and long-term natural carbon fluxes, carbon sequestration, and human emissions contribute to the net global emissions (concentrations) trajectories required to reach various concentration (emission) targets. Under this grant, 21 research publications were produced. In addition, this grant supported a number of graduate and undergraduate students whose fundamental research was to learn a disciplinary field in climate change (e.g., ecological dynamics and ocean circulations) and then complete research on how this field could be linked to the other factors we need to consider in its dynamics (e.g., land use, ocean and terrestrial carbon sequestration and climate change).

Dr. Atul Jain

2005-04-17T23:59:59.000Z

136

Modeling Exposure to Persistent Chemicals in Hazard and Risk Assessment  

E-Print Network [OSTI]

of organohalogen contaminants (dioxins, PCB, PBDE andInvestigation into levels of dioxins, furans, PCBs and PBDEsfor risk assessment of dioxin-contaminated sites. Ambio 36:

Cowan-Ellsberry, Christina E.

2010-01-01T23:59:59.000Z

137

Assessing the Accuracy of Contact Angle Measurements for Sessile Drops on Liquid-Repellent Surfaces  

E-Print Network [OSTI]

Gravity-induced sagging can amplify variations in goniometric measurements of the contact angles of sessile drops on super-liquid-repellent surfaces. The very large value of the effective contact angle leads to increased ...

Srinivasan, Siddarth

138

A phenomenological muscle model to assess history dependent effects in human movement  

E-Print Network [OSTI]

A phenomenological muscle model to assess history dependent effects in human movement C.P. Mc of the history dependent effects. The phenomenological model of stretch-induced force enhancement was dependent

Ben-Yakar, Adela

139

Assessing the Potential of Using Traffic Simulation Model Results for Evaluating Automatic Incident Detection Algorithms  

E-Print Network [OSTI]

Assessing the Potential of Using Traffic Simulation Model Results for Evaluating Automatic Incident of such a test-bed would be the ability to incorporate synthetic data produced by a simulation model since

Hellinga, Bruce

140

Langasite Surface Acoustic Wave Gas Sensors: Modeling and Verification  

SciTech Connect (OSTI)

We report finite element simulations of the effect of conductive sensing layers on the surface wave velocity of langasite substrates. The simulations include both the mechanical and electrical influences of the conducting sensing layer. We show that three-dimensional simulations are necessary because of the out-of-plane displacements of the commonly used (0, 138.5, 26.7) Euler angle. Measurements of the transducer input admittance in reflective delay-line devices yield a value for the electromechanical coupling coefficient that is in good agreement with the three-dimensional simulations on bare langasite substrate. The input admittance measurements also show evidence of excitation of an additional wave mode and excess loss due to the finger resistance. The results of these simulations and measurements will be useful in the design of surface acoustic wave gas sensors.

Zheng, Peng; Greve, David W.; Oppenheim, Irving J.

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" 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

Surface spectroscopic studies of mono- and bimetallic model catalysts  

E-Print Network [OSTI]

This dissertation is focused on understanding heterogeneous bimetallic catalysts using model catalyst systems, such as Pd-Au/Mo(110), Pd/Au(111) and Pd/Au(100). Monometallic and bimetallic model catalysts, composed of Pd and Au, were prepared...

Yi, Cheol-Woo

2007-04-25T23:59:59.000Z

142

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

143

Assessment of Managed Aquifer Recharge Site Suitability Using a GIS and Modeling  

E-Print Network [OSTI]

with a regional groundwater model to assess the hydrologic impact of potential MAR placement and operating planning, including evaluation of options for enhancing groundwater resources. Introduction ManagedAssessment of Managed Aquifer Recharge Site Suitability Using a GIS and Modeling by Tess A. Russo1

Fisher, Andrew

144

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

E-Print Network [OSTI]

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

Winter, Jonathan (Jonathan Mark)

2010-01-01T23:59:59.000Z

145

Computation Modeling and Assessment of Nanocoatings for Ultra Supercritical Boilers  

SciTech Connect (OSTI)

Forced outages and boiler unavailability of coal-fired fossil plants is most often caused by fire-side corrosion of boiler waterwalls and tubing. Reliable coatings are required for Ultrasupercritical (USC) application to mitigate corrosion since these boilers will operate at a much higher temperatures and pressures than in supercritical (565 C {at} 24 MPa) boilers. Computational modeling efforts have been undertaken to design and assess potential Fe-Cr-Ni-Al systems to produce stable nanocrystalline coatings that form a protective, continuous scale of either Al{sub 2}O{sub 3} or Cr{sub 2}O{sub 3}. The computational modeling results identified a new series of Fe-25Cr-40Ni with or without 10 wt.% Al nanocrystalline coatings that maintain long-term stability by forming a diffusion barrier layer at the coating/substrate interface. The computational modeling predictions of microstructure, formation of continuous Al{sub 2}O{sub 3} scale, inward Al diffusion, grain growth, and sintering behavior were validated with experimental results. Advanced coatings, such as MCrAl (where M is Fe, Ni, or Co) nanocrystalline coatings, have been processed using different magnetron sputtering deposition techniques. Several coating trials were performed and among the processing methods evaluated, the DC pulsed magnetron sputtering technique produced the best quality coating with a minimum number of shallow defects and the results of multiple deposition trials showed that the process is repeatable. scale, inward Al diffusion, grain growth, and sintering behavior were validated with experimental results. The cyclic oxidation test results revealed that the nanocrystalline coatings offer better oxidation resistance, in terms of weight loss, localized oxidation, and formation of mixed oxides in the Al{sub 2}O{sub 3} scale, than widely used MCrAlY coatings. However, the ultra-fine grain structure in these coatings, consistent with the computational model predictions, resulted in accelerated Al diffusion from the coating into the substrate. An effective diffusion barrier interlayer coating was developed to prevent inward Al diffusion. The fire-side corrosion test results showed that the nanocrystalline coatings with a minimum number of defects have a great potential in providing corrosion protection. The coating tested in the most aggressive environment showed no evidence of coating spallation and/or corrosion attack after 1050 hours exposure. In contrast, evidence of coating spallation in isolated areas and corrosion attack of the base metal in the spalled areas were observed after 500 hours. These contrasting results after 500 and 1050 hours exposure suggest that the premature coating spallation in isolated areas may be related to the variation of defects in the coating between the samples. It is suspected that the cauliflower-type defects in the coating were presumably responsible for coating spallation in isolated areas. Thus, a defect free good quality coating is the key for the long-term durability of nanocrystalline coatings in corrosive environments. Thus, additional process optimization work is required to produce defect-free coatings prior to development of a coating application method for production parts.

J. Shingledecker; D. Gandy; N. Cheruvu; R. Wei; K. Chan

2011-06-21T23:59:59.000Z

146

Information on Hydrologic Conceptual Models, Parameters, Uncertainty Analysis, and Data Sources for Dose Assessments at Decommissioning Sites  

SciTech Connect (OSTI)

This report addresses issues related to the analysis of uncertainty in dose assessments conducted as part of decommissioning analyses. The analysis is limited to the hydrologic aspects of the exposure pathway involving infiltration of water at the ground surface, leaching of contaminants, and transport of contaminants through the groundwater to a point of exposure. The basic conceptual models and mathematical implementations of three dose assessment codes are outlined along with the site-specific conditions under which the codes may provide inaccurate, potentially nonconservative results. In addition, the hydrologic parameters of the codes are identified and compared. A methodology for parameter uncertainty assessment is outlined that considers the potential data limitations and modeling needs of decommissioning analyses. This methodology uses generic parameter distributions based on national or regional databases, sensitivity analysis, probabilistic modeling, and Bayesian updating to incorporate site-specific information. Data sources for best-estimate parameter values and parameter uncertainty information are also reviewed. A follow-on report will illustrate the uncertainty assessment methodology using decommissioning test cases.

Meyer, Philip D.; Gee, Glendon W.; Nicholson, Thomas J.

2000-02-28T23:59:59.000Z

147

Bias Correction and Bayesian Model Averaging for Ensemble Forecasts of Surface Wind Direction  

E-Print Network [OSTI]

from numerical weather prediction models, which is based on a state-of-the-art circular-processing techniques for forecasts from numerical weather prediction models tend to become ineffective or inapplicableBias Correction and Bayesian Model Averaging for Ensemble Forecasts of Surface Wind Direction Le

Washington at Seattle, University of

148

MODELLING SURFACE HOAR FORMATION AND EVOLUTION ON MOUNTAIN SLOPES Simon Horton1  

E-Print Network [OSTI]

. Weather station data and forecasted data from the GEM15 numerical weather prediction model were used evaluates surface hoar size predictions made with empirical weather based models and discusses how buried and south facing slopes in the Columbia Mountains. Two models were developed to predict crystal size, one

Jamieson, Bruce

149

Risk assessment of surface vs subsea blowout preventers (bops) on mobile offshore drilling units focusing on riser failure and the use of subsea shear rams  

E-Print Network [OSTI]

The use of a slim, high-pressure drilling riser for surface blowout preventer operations in the deepwater Gulf of Mexico was assessed as an alternative to conventional drilling procedures from floating units. Comparison of the low- and high...

Melendez, Jorge Luis

2006-08-16T23:59:59.000Z

150

A Subbasin-based framework to represent land surface processes in an Earth System Model  

SciTech Connect (OSTI)

Realistically representing spatial heterogeneity and lateral land surface processes within and between modeling units in earth system models is important because of their implications to surface energy and water exchange. The traditional approach of using regular grids as computational units in land surface models and earth system models may lead to inadequate representation of lateral movements of water, energy and carbon fluxes, especially when the grid resolution increases. Here a new subbasin-based framework is introduced in the Community Land Model (CLM), which is the land component of the Community Earth System Model (CESM). Local processes are represented assuming each subbasin as a grid cell on a pseudo grid matrix with no significant modifications to the existing CLM modeling structure. Lateral routing of water within and between subbasins is simulated with the subbasin version of a recently-developed physically based routing model, Model for Scale Adaptive River Routing (MOSART). As an illustration, this new framework is implemented in the topographically diverse region of the U.S. Pacific Northwest. The modeling units (subbasins) are delineated from high-resolution Digital Elevation Model while atmospheric forcing and surface parameters are remapped from the corresponding high resolution datasets. The impacts of this representation on simulating hydrologic processes are explored by comparing it with the default (grid-based) CLM representation. In addition, the effects of DEM resolution on parameterizing topography and the subsequent effects on runoff processes are investigated. Limited model evaluation and comparison showed that small difference between the averaged forcing can lead to more significant difference in the simulated runoff and streamflow because of nonlinear horizontal processes. Topographic indices derived from high resolution DEM may not improve the overall water balance, but affect the partitioning between surface and subsurface runoff. More systematic analyses are needed to determine the relative merits of the subbasin representation compared to the commonly used grid-based representation, especially when land surface models are approaching higher resolutions.

Tesfa, Teklu K.; Li, Hongyi; Leung, Lai-Yung R.; Huang, Maoyi; Ke, Yinghai; Sun, Yu; Liu, Ying

2014-05-20T23:59:59.000Z

151

Inverse modeling of surface emissions for local pollution: A new methodology applied to academic test cases  

E-Print Network [OSTI]

Inverse modeling of surface emissions for local pollution: A new methodology applied to academic; (2) LISA Creteil France Needs: Optimize surface emissions using daily recorded ozone and NOX by PRIMEQUAL2, program of the french ministry of environment Firstguess emissions inventory for the Paris

Menut, Laurent

152

Modeling the free energy surfaces of electron transfer in condensed phases  

E-Print Network [OSTI]

PROOF COPY 509037JCP Modeling the free energy surfaces of electron transfer in condensed phases analytical solution for the ET free energy surfaces demonstrates the following features: i the range of ET reaction coordinates is limited by a one-sided fluctuation band, ii the ET free energies are infinite

Matyushov, Dmitry

153

Water at the Surfaces of Aligned Phospholipid Multibilayer Model Membranes Probed with Ultrafast Vibrational  

E-Print Network [OSTI]

Water at the Surfaces of Aligned Phospholipid Multibilayer Model Membranes Probed with Ultrafast@stanford.edu Abstract: The dynamics of water at the surface of artificial membranes composed of aligned multibilayers pump-probe spectroscopy. The experiments are performed at various hydration levels, x ) 2 - 16 water

Fayer, Michael D.

154

Discrepancies in the Prediction of Solar Wind using Potential Field Source Surface Model: An  

E-Print Network [OSTI]

Discrepancies in the Prediction of Solar Wind using Potential Field Source Surface Model. This inverse relation has been made use of in the prediction of solar wind speed at 1 AU using a potential between the magnetic flux tube expansion factor (FTE) at the source surface and the solar wind speed

Zhao, Xuepu

155

Soil moisture and soil-litter mixing effects on surface litter decomposition: A controlled environment assessment  

E-Print Network [OSTI]

temperature and radiant energy levels and soil-litter mixing. Temperature and radiant energy effects on litterSoil moisture and soil-litter mixing effects on surface litter decomposition: A controlled University, Las Cruces, NM 88003, USA c Department of Plant and Soil Sciences, University of Kentucky

Archer, Steven R.

156

Model for a web based medical technology assessment system  

E-Print Network [OSTI]

will form the backbone of this system. Various queries can be run to produce the desired results. This system will provide a means for assessing the currently available medical technology. Based on the information present in the system clinical engineers...

Prabhu, Gopal

1999-01-01T23:59:59.000Z

157

Modeling toxic endpoints for improving human health risk assessment  

E-Print Network [OSTI]

Risk assessment procedures for mixtures of polycyclic aromatic hydrocarbons (PAHs) present a problem due to the lack of available potency and toxicity data on mixtures and individual compounds. This study examines the toxicity of parent compound...

Bruce, Erica Dawn

2009-05-15T23:59:59.000Z

158

Mapping surface fuels using LIDAR and multispectral data fusion for fire behavior modeling  

E-Print Network [OSTI]

, LIDAR derived data provides accurate estimates of surface fuel parameters efficiently and accurately over extensive areas of forests. This study demonstrates the importance of using accurate maps of fuel models derived using new LIDAR remote sensing...

Mutlu, Muge

2009-05-15T23:59:59.000Z

159

The Surface-Pressure Signature of Atmospheric Tides in Modern Climate Models  

E-Print Network [OSTI]

Although atmospheric tides driven by solar heating are readily detectable at the earth’s surface as variations in air pressure, their simulations in current coupled global climate models have not been fully examined. This ...

Covey, Curt

160

IEEE JOURNAL OF OCEANIC ENGINEERING, VOL. 34, NO. 3, JULY 2009 239 Modeling Surface Multipath Effects  

E-Print Network [OSTI]

IEEE JOURNAL OF OCEANIC ENGINEERING, VOL. 34, NO. 3, JULY 2009 239 Modeling Surface Multipath_davis@hotmail.com; bryn@uiuc.edu). P. T. Gough is with the Electrical and Computer Engineering Depart- ment, University

Bhargava, Rohit

Note: This page contains sample records for the topic "models assessing surface" 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

Modeling of surface oxidation and oxidation induced damage in metal matrix composites  

E-Print Network [OSTI]

Surface oxidation in metal matrix composites (MMC's) is modeled by Fickian diffusion of oxygen in both the oxide layer and metal matrix. The oxidation process and the resulting immobilized oxygen at the interface is accounted for by the introduction...

Ma, Xinzheng

1995-01-01T23:59:59.000Z

162

Development of legged, wheeled, and hybrid rover mobility models to facilitate planetary surface exploration mission analysis  

E-Print Network [OSTI]

This work discusses the Mars Surface Exploration (MSE) tool and its adaptation to model rovers featuring legged, wheeled, and hybrid mobility. MSE is a MATLAB based systems engineering tool that is capable of rapidly ...

McCloskey, Scott H. (Scott Haddon)

2007-01-01T23:59:59.000Z

163

Parameter estimation of coupled water and energy balance models based on stationary constraints of surface states  

E-Print Network [OSTI]

[1] We use a conditional averaging approach to estimate the parameters of a land surface water and energy balance model and then use the estimated parameters to partition net radiation into latent, sensible, and ground ...

Sun, Jian

164

[10-386] Assessing and Improving the Scale Dependence of Ecosystem Processes in Earth System Models  

E-Print Network [OSTI]

. Goodale Cornell U. *Overall Project Lead *Lead Institution Intellectual Merit: Earth system models include policies. Our research assesses and improves Earth system model simulations of the carbon cycle, ecosystem of the Community Climate System Model/Community Earth System Model, which includes statistical meteorological

165

United: How one computer model makes Texas surface water management possible  

E-Print Network [OSTI]

Story by Leslie Lee Summer 2013 tx H2O 3 Photo by Kathleen Phillips, Texas A&M AgriLife UNITED How one computer model makes Texas surface water management possible Managing surface water supplies in Texas is complex, to say the least. Multiple... of conditions. W#15;P enables surface water managers throughout Texas to allocate water resources, plan for the future and ensure there is enough water for environmental as well as human needs. A statewide surface water permitting system is born Prior...

Lee, Leslie

2013-01-01T23:59:59.000Z

166

Direct releases to the surface and associated complementary cumulative distribution functions in the 1996 performance assessment for the Waste Isolation Pilot Plant: Cuttings, cavings and spallings  

SciTech Connect (OSTI)

The following topics related to the treatment of cuttings, cavings and spallings releases to the surface environment in the 1996 performance assessment for the Waste Isolation Pilot Plant (WIPP) are presented: (1) mathematical description of models. (2) uncertainty and sensitivity analysis results arising from subjective (i.e., epistemic) uncertainty for individual releases, (3) construction of complementary cumulative distribution functions (CCDFs) arising from stochastic (i.e., aleatory) uncertainty, and (4) uncertainty and sensitivity analysis results for CCDFs. The presented results indicate that direct releases due to cuttings, cavings and spallings do not constitute a serious threat to the effectiveness of the WIPP as a disposal facility for transuranic waste. Even when the effects of uncertain analysis inputs are taken into account, the CCDFs for cuttings, cavings and spallings releases fall substantially to the left of the boundary line specified in the US Environmental Protection Agency standard for the geologic disposal of radioactive waste (40 CFR 191, 40 CFR 194).

BERGLUND,J.W.; GARNER,J.W.; HELTON,JON CRAIG; JOHNSON,J.D.; SMITH,L.N.; ANDERSON,R.P.

2000-05-22T23:59:59.000Z

167

Direct releases to the surface and associated complementary cumulative distribution functions in the 1996 performance assessments for the Waste Isolation Pilot Plant: Direct brine release  

SciTech Connect (OSTI)

The following topics related to the treatment of direct brine releases to the surface environment in the 1996 performance assessment for the Waste Isolation Pilot Plant (WIPP) are presented (1) mathematical description of models, (2) uncertainty and sensitivity analysis results arising from subjective (i.e., epistemic) uncertainty for individual releases, (3) construction of complementary cumulative distribution functions (CCDFs) arising from stochastic (i.e., aleatory) uncertainty, and (4) uncertainty and sensitivity analysis results for CCDFs. The presented analyses indicate that direct brine releases do not constitute a serious threat to the effectiveness of the WIPP as a disposal facility for transuranic waste. Even when the effects of uncertain analysis inputs are taken into account, the CCDFs for direct brine releases fall substantially to the left of the boundary line specified in the US Environmental Protection Agency's standard for the geologic disposal of radioactive waste (4O CFR 191.40 CFR 194).

STOELZEL,D.M.; O'BRIEN,D.G.; GARNER,J.W.; HELTON,JON CRAIG; JOHNSON,J.D.; SCOTT,L.N.

2000-05-19T23:59:59.000Z

168

An anticipatory integrated assessment of regional acidification: The RAINS-Asia model  

SciTech Connect (OSTI)

Across large parts of Asia, air pollution problems are becoming more and more evident. Rainfall in some areas, including China, Japan, and Thailand, has been measured to be 10 times more acidic than unpolluted rain. Increasing evidence of acidification damage to ecosystems such as surface waters, soils, and economically important crops, is beginning to appear. In addition, urban air quality in many areas of the region continues to decrease. Current economic forecasts predict continued rapid economic growth in the region, which will bring with it increasing emissions of air pollutants, especially sulfur. The total primary energy demand in Asia currently doubles every twelve years (as compared to a world average of every 28 years). Coal is expected to continue to be the dominant energy source, with coal demand projected to increase by 65 percent per year, a rate that outpaces regional economic growth. If current trends in economic development and energy use in Asia continue, emissions of sulfur dioxide, one of the key components in acid rain, will more than triple within the next 30 years. Many ecosystems will be unable to continue to absorb these increased levels of pollution without harmful effects, thus creating a potential danger for irreversible environmental damage in many areas. In view of the potential environmental consequences of projected growth in Asian energy consumption, emissions, and air pollution, the World Bank, together with the Asian Development Bank, have funded a project to develop and implement an integrated assessment model for the acid deposition phenomenon in Asia. The Regional Air Pollution INformation and Simulation model for Asia (RAINS-Asia) is a software tool to help decision makers assess and project future trends in emissions, transport, and deposition of air pollutants, and their potential environmental effects.

Amann, M. [International Institute for Applied Systems Analysis, Laxenburg (Austria); Carmichael, G.R. [Univ. of Iowa, Iowa City, IA (United States); Foell, W. [Resource Management Associates, Madison, WI (United States)] [and others

1996-12-31T23:59:59.000Z

169

Simulating the Transverse Ising Model on a Quantum Computer: Error Correction with the Surface Code  

E-Print Network [OSTI]

We estimate the resource requirements for the quantum simulation of the ground state energy of the one dimensional quantum transverse Ising model (TIM), based on the surface code implementation of a fault tolerant quantum computer. The surface code approach has one of the highest known tolerable error rates (1%) which makes it currently one of the most practical quantum computing schemes. Compared to results of the same model using the concatenated Steane code, the current results indicate that the simulation time is comparable but the number of physical qubits for the surface code is 2-3 orders of magnitude larger than that of the concatenation code. Considering that the error threshold requirements of the surface code is four orders of magnitude higher than the concatenation code, building a quantum computer with a surface code implementation appears more promising given current physical hardware capabilities.

Hao You; Michael R. Geller; P. C. Stancil

2013-03-29T23:59:59.000Z

170

A stochastic model to mimic periodic surface currents in embayments  

E-Print Network [OSTI]

instruments are needing to accurately determine how the tide moves throughout the bay. In addition wind can pile up water in areas adding to the tidal height. Tidal currents are even more difficult to measure. Since wind along coasts is usually persistent... dynamics, some locations have very strong tidal currents (narrow straits or resonant bays). Elsewhere within an embayment, the tidal component may be a fraction of the total current, in any case, a wind-only current model will eventually diverge from...

Paternostro, Christopher Lee

2001-01-01T23:59:59.000Z

171

A new analytic-adaptive model for EGS assessment, development...  

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

Categorical Exclusion Determination Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs Predicting Stimulation Response...

172

The Niobrara River Basin Study: Using Various Models to Assess  

E-Print Network [OSTI]

Seminar Series Brandi Flyr, Ph.D. Integrated Water Management Division Nebraska Department of Natural;#12;Integrated Water Management Identify Management Setting Assess Water Resources Understand & Predict Set effects of various water management strategies in order to develop water management tools #12;Goals

Farritor, Shane

173

Models used to assess the performance of photovoltaic systems.  

SciTech Connect (OSTI)

This report documents the various photovoltaic (PV) performance models and software developed and utilized by researchers at Sandia National Laboratories (SNL) in support of the Photovoltaics and Grid Integration Department. In addition to PV performance models, hybrid system and battery storage models are discussed. A hybrid system using other distributed sources and energy storage can help reduce the variability inherent in PV generation, and due to the complexity of combining multiple generation sources and system loads, these models are invaluable for system design and optimization. Energy storage plays an important role in reducing PV intermittency and battery storage models are used to understand the best configurations and technologies to store PV generated electricity. Other researcher's models used by SNL are discussed including some widely known models that incorporate algorithms developed at SNL. There are other models included in the discussion that are not used by or were not adopted from SNL research but may provide some benefit to researchers working on PV array performance, hybrid system models and energy storage. The paper is organized into three sections to describe the different software models as applied to photovoltaic performance, hybrid systems, and battery storage. For each model, there is a description which includes where to find the model, whether it is currently maintained and any references that may be available. Modeling improvements underway at SNL include quantifying the uncertainty of individual system components, the overall uncertainty in modeled vs. measured results and modeling large PV systems. SNL is also conducting research into the overall reliability of PV systems.

Stein, Joshua S.; Klise, Geoffrey T.

2009-12-01T23:59:59.000Z

174

Modelling of a captive unmanned aerial system teledetecting oil pollution on sea surface  

E-Print Network [OSTI]

-Water Horizon crisis in the Gulf of Mexico, numerous aerial means were used to detect oil pollution locationsModelling of a captive unmanned aerial system teledetecting oil pollution on sea surface F. Muttin-spill, detection, dynamic modelling, winch, maritime pollution. 1 Introduction During 2010, and the Deep

Paris-Sud XI, Université de

175

Electric field noise above surfaces: a model for heating rate scaling law in ion traps  

E-Print Network [OSTI]

We present a model for the scaling laws of the electric field noise spectral density as a function of the distance, $d$, above a conducting surface. Our analytical approach models the patch potentials by introducing a correlation length, $\\zeta$, of the electric potential on the surface. The predicted scaling laws are in excellent agreement with two different classes of experiments (cold trapped ions and cantilevers), that span at least four orders of magnitude of $d$. According to this model, heating rate in miniature ion traps could be greatly reduced by proper material engineering.

Romain Dubessy; Thomas Coudreau; Luca Guidoni

2008-12-17T23:59:59.000Z

176

Conceptual design of an integrated technology model for carbon policy assessment.  

SciTech Connect (OSTI)

This report describes the conceptual design of a technology choice model for understanding strategies to reduce carbon intensity in the electricity sector. The report considers the major modeling issues affecting technology policy assessment and defines an implementable model construct. Further, the report delineates the basis causal structure of such a model and attempts to establish the technical/algorithmic viability of pursuing model development along with the associated analyses.

Backus, George A.; Dimotakes, Paul E. (NASA Jet Propulsion Laboratory, Pasadena, CA)

2011-01-01T23:59:59.000Z

177

Assessing the protective effect of mountain forests against rockfall using a 3D simulation model  

E-Print Network [OSTI]

Assessing the protective effect of mountain forests against rockfall using a 3D simulation model and compared the results obtained with the 3D simulation model RockyFor with empirical data on tree impacts; Rockfall; 3D simulation model; Swiss Alps 1. Introduction Many mountain forests effectively protect people

Stoffel, Markus

178

Cognitive Assessment Models with Few Assumptions, and Connections with Nonparametric IRT  

E-Print Network [OSTI]

Cognitive Assessment Models with Few Assumptions, and Connections with Nonparametric IRT Brian of the monotonicity conditions discussed in Section 4. #12; Abstract In recent years, as cognitive theories and other cognitive features needed to perform tasks in a particular assess­ ment domain. Cognitive

Junker, Brian

179

Assessing resilience and state-transition models with historical records of cheatgrass Bromus tectorum  

E-Print Network [OSTI]

Assessing resilience and state-transition models with historical records of cheatgrass Bromus. Bestelmeyer2 and X. Ben Wu1 1 Department of Ecosystem Science and Management, Texas A&M University, 2138 TAMU. This requires management frameworks that can assess ecosystem dynamics, both within and between alternative

180

A simplified physical model for assessing solar radiation over Brazil using GOES 8 visible imagery  

E-Print Network [OSTI]

A simplified physical model for assessing solar radiation over Brazil using GOES 8 visible imagery; published 30 January 2004. [1] Solar radiation assessment by satellite is constrained by physical Composition and Structure: Transmission and scattering of radiation; KEYWORDS: solar radiation, satellite

Note: This page contains sample records for the topic "models assessing surface" 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

U.S. GEOLOGICAL SURVEY ASSESSMENT MODEL FOR UNDISCOVERED CONVENTIONAL OIL, GAS, AND NGL  

E-Print Network [OSTI]

AM-i Chapter AM U.S. GEOLOGICAL SURVEY ASSESSMENT MODEL FOR UNDISCOVERED CONVENTIONAL OIL, GAS Survey (USGS) periodically conducts assessments of the oil, gas, and natural-gas liquids (NGL) resources by the USGS in1998 for undiscovered oil, gas, and NGL resources that reside in conventional accumulations

Laughlin, Robert B.

182

Climate Change Modeling and Downscaling Issues and Methodological Perspectives for the U.S. National Climate Assessment  

SciTech Connect (OSTI)

This is the full workshop report for the modeling workshop we did for the National Climate Assessment, with DOE support.

Janetos, Anthony C.; Collins, William D.; Wuebbles, D.J.; Diffenbaugh, Noah; Hayhoe, Katharine; Hibbard, Kathleen A.; Hurtt, George

2012-03-31T23:59:59.000Z

183

Application of a Hydrodynamic Model for Assessing the Hydraulic Capacity and Flow Field at Willamette Falls Dam, Oregon  

SciTech Connect (OSTI)

The Willamette Falls Hydroelectric Power Dam, operated by Portland General Electric (PGE), is located on the Willamette River, Oregon. The Project site consists of T.W. Sullivan Power Plant and a 2,950-ft-long spillway located on the top of the Willamette Falls Dam. As part of the effort of protection and enhancement of environmental resources, a flow control structure at the dam was proposed to improve the flow field and enhance the downstream juvenile fish passage in the region just upstream of the forebay (pre-forebay). The flow in the pre-forebay of Willamette Falls Dam is affected by the complex geometry and bathymetry, powerhouse flow, fish ladder flow and the spillway around the dam. The expectation was that the flow would be sensitive to the proposed flow control structures and could be modified to enhance downstream migration. In this study, a three-dimensional, free-surface hydrodynamic model (EFDC) was developed for the pre-forebay region of Willamette Falls to evaluate the feasibility of the proposed alternative and its effect on the flow field in two different flow regimes (low and high river flow), as well as to assess the hydraulic capacity of flow control structures. One of the key challenges in this modeling study was to properly specify the free open boundary conditions along the 2,950-feet-long spillway. In this study, a pressure boundary condition based on hydraulic head rating curves was applied to the free spillway boundary. The numerical model was calibrated with ADP velocity measurements at 17 stations for the existing low flow condition. Good agreements between model results and measured data were obtained, indicating the successful application of pressure boundary condition on the free spillway boundary. The calibrated model was applied to simulate the flow field and free surface elevation in the high flow region near the control flow structures under different alternative conditions. The model results were used to evaluate the effectiveness of flow control structure alternative for downstream fish passage. The model was also used to estimate the hydraulic capacity based on the water surface head drops upstream of the structures. This model application demonstrated that a free surface coastal model can be used successfully to examine free surface hydraulic problems near high velocity regions upstream of spillways at dams.

Lee, Cheegwan; Yang, Zhaoqing; Khangaonkar, Tarang P.; Divers, Arya-Behbehani

2006-08-03T23:59:59.000Z

184

Using species distribution models to inform IUCN Red List assessments  

E-Print Network [OSTI]

to these as “SRLI species” because the occurrence data for these came from the plant component of the Sampled Red List Index (SRLI), an indicator to measure the current rate of loss of biodiversity by tracking trends in the conservation status of 6 a randomly... the Mesoamerica biodiversity hotspot (Myers et al. 2000). Many species in this region are poorly represented in the world’s herbaria, so limited knowledge of their true distribution exists; nonetheless, conservation assessments are urgently needed...

Syfert, Mindy M.; Joppa, Lucas; Smith, Matthew J.; Coomes, David A.; Bachman, Steven P.; Brummitt, Neil A.

2014-07-26T23:59:59.000Z

185

A Statistical Model to Assess Indirect CO2 Emissions of the UAE Residential Sector  

E-Print Network [OSTI]

. Determination of household energy using ?fingerprints? from energy billing data. Energy Research 10(4), pp: 393?405. [5] Snakin JPA, 2000. An engineering model for heating energy and emission assessment The case of North Karelia, Finland. Applied Energy...

Radhi, H.; Fikry, F.

2010-01-01T23:59:59.000Z

186

Integrated modelling and assessment of regional groundwater resources in Germany and Benin, West Africa  

E-Print Network [OSTI]

1 Integrated modelling and assessment of regional groundwater resources in Germany and Benin, West.J.S. SONNEVELD [1] Institute of Hydraulic Engineering, Universitaet Stuttgart, Germany (Roland Conservation University of Bonn, Germany [3] Institute of Landscape Planning and Ecology, University

Cirpka, Olaf Arie

187

Using Noncompensatory Models in Cognitive Diagnostic Mathematics Assessments: An Evaluation Based on Empirical Data  

E-Print Network [OSTI]

The present study evaluates the performance of four noncompensatory cognitive diagnostic models -- AHM, DINA, Fusion, and Bayesian Networks -- using both formative and large-scale mathematics assessments (Fraction dataset, ...

Zhao, Fei

2013-08-31T23:59:59.000Z

188

A new analytic-adaptive model for EGS assessment, development...  

Open Energy Info (EERE)

Investigator(s) George Danko, UNR Other Principal Investigators Jens Birkholzer, LBNL; Jaak Daemen, UNR Targets Milestones The model development work follows three main...

189

assessment models version: Topics by E-print Network  

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

Szilagyi a is modeled with a spatially and temporally discretized version of the linear kinematic wave equation written-aquifer interactions; Baseflow separation; Flow routing;...

190

assessment model version: Topics by E-print Network  

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

Szilagyi a is modeled with a spatially and temporally discretized version of the linear kinematic wave equation written-aquifer interactions; Baseflow separation; Flow routing;...

191

Modeling Exposure to Persistent Chemicals in Hazard and Risk Assessment  

E-Print Network [OSTI]

chlorinated pesticides, e.g. , DDT) based on Swedish marketInvestigating the global fate of DDT: Model evaluation anddichlorodiphenyltrichloroethane (DDT), and its degradation

Cowan-Ellsberry, Christina E.

2010-01-01T23:59:59.000Z

192

Assessment of Combustion and Turbulence Models for the Simulation...  

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

models were investigated along with chemical kinetic mechanisms simulating a biodiesel-fueled engine deer09ren.pdf More Documents & Publications Low Temperature...

193

An investigation into the use of biokinetic models when assessing intakes of plutonium  

E-Print Network [OSTI]

AN INVESTIGATION INTO THE USE OF BIOKINETIC MODELS WHEN ASSESSING INTAKES OF PLUTONIUM A Thesis by BRIAN ANDREW HRYCUSHKO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 2008 Major Subject: Health Physics AN INVESTIGATION INTO THE USE OF BIOKINETIC MODELS WHEN ASSESSING INTAKES OF PLUTONIUM A Thesis by BRIAN ANDREW HRYCUSHKO Submitted...

Hrycushko, Brian Andrew

2008-10-10T23:59:59.000Z

194

Statewide and Electricity-Sector Models for Economic Assessments of  

E-Print Network [OSTI]

economic models applied to such diverse fields as climate change policy, alternative- fueled vehicles, fuel Economic Research Organization and Affiliate Faculty with the Public Policy Center UHM. Paul Bernstein, Ph....................................................................................................................... 6 2. The Hawaii Computable General Equilibrium Model (H-CGE)............................ 8 2.a. Data

195

Implementation of surface tension with wall adhesion effects in a three-dimensional finite element model for fluid flow  

E-Print Network [OSTI]

- 1 - Implementation of surface tension with wall adhesion effects in a three-dimensional finite element modelling of surface tension. The external stress vectors associated with surface tension a drop of liquid on a plane is treated. Keywords : surface tension, finite element method, average

Boyer, Edmond

196

Surface tension and curvature energy of quark matter in the NJL model  

E-Print Network [OSTI]

In this paper we study the surface tension and the curvature energy of three-flavor quark matter in equilibrium under weak interactions within the Nambu-Jona-Lasinio model. We include the effect of color superconductivity and describe finite size effects within the multiple reflection expansion (MRE) framework. Our calculations result in large values of the surface tension which disfavor the formation of mixed phases at the hadron-quark inter-phase inside a hybrid star.

G. Lugones; A. G. Grunfeld; M. Al Ajmi

2013-10-14T23:59:59.000Z

197

Chaotic Vibration of a Quarter-Car Model Excited by the Road Surface Profile  

E-Print Network [OSTI]

The Melnikov criterion is used to examine a global homoclinic bifurcation and transition to chaos in the case of a quarter car model excited kinematically by the road surface profile. By analyzing the potential an analytic expression is found for the homoclinic orbit. By introducing an harmonic excitation term and damping as perturbations, the critical Melnikov amplitude of the road surface profile is found, above which the system can vibrate chaotically.

Grzegorz Litak; Marek Borowiec; Michael I. Friswell; Kazimierz Szabelski

2006-01-14T23:59:59.000Z

198

Utility of Social Modeling in Assessment of a State’s Propensity for Nuclear Proliferation  

SciTech Connect (OSTI)

This report is the third and final report out of a set of three reports documenting research for the U.S. Department of Energy (DOE) National Security Administration (NASA) Office of Nonproliferation Research and Development NA-22 Simulations, Algorithms, and Modeling program that investigates how social modeling can be used to improve proliferation assessment for informing nuclear security, policy, safeguards, design of nuclear systems and research decisions. Social modeling has not to have been used to any significant extent in a proliferation studies. This report focuses on the utility of social modeling as applied to the assessment of a State's propensity to develop a nuclear weapons program.

Coles, Garill A.; Brothers, Alan J.; Whitney, Paul D.; Dalton, Angela C.; Olson, Jarrod; White, Amanda M.; Cooley, Scott K.; Youchak, Paul M.; Stafford, Samuel V.

2011-06-01T23:59:59.000Z

199

The effect of ozone on nicotine desorption from model surfaces:evidence for heterogeneous chemistry  

SciTech Connect (OSTI)

Assessment of secondhand tobacco smoke exposure using nicotine as a tracer or biomarker is affected by sorption of the alkaloid to indoor surfaces and by its long-term re-emission into the gas phase. However, surface chemical interactions of nicotine have not been sufficiently characterized. Here, the reaction of ozone with nicotine sorbed to Teflon and cotton surfaces was investigated in an environmental chamber by monitoring nicotine desorption over a week following equilibration in dry or humid air (65-70 % RH). The Teflon and cotton surfaces had N{sub 2}-BET surface areas of 0.19 and 1.17 m{sup 2} g{sup -1}, and water mass uptakes (at 70 % RH) of 0 and 7.1 % respectively. Compared with dry air baseline levels in the absence of O{sub 3}, gas phase nicotine concentrations decrease, by 2 orders of magnitude for Teflon after 50 h at 20-45 ppb O{sub 3}, and by a factor of 10 for cotton after 100 h with 13-15 ppb O{sub 3}. The ratios of pseudo first-order rate constants for surface reaction (r) to long-term desorption (k) were r/k = 3.5 and 2.0 for Teflon and cotton surfaces, respectively. These results show that surface oxidation was competitive with desorption. Hence, oxidative losses could significantly reduce long-term re-emissions of nicotine from indoor surfaces. Formaldehyde, N-methylformamide, nicotinaldehyde and cotinine were identified as oxidation products, indicating that the pyrrolidinic N was the site of electrophilic attack by O{sub 3}. The presence of water vapor had no effect on the nicotine-O{sub 3} reaction on Teflon surfaces. By contrast, nicotine desorption from cotton in humid air was unaffected by the presence of ozone. These observations are consistent with complete inhibition of ozone-nicotine surface reactions in an aqueous surface film present in cotton but not in Teflon surfaces.

Destaillats, Hugo; Singer, Brett C.; Lee, Sharon K.; Gundel, LaraA.

2005-05-01T23:59:59.000Z

200

Physical Stability of Long-Term Surface Barriers-Assessment of Potentially Disruptive Natural Events  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006Photovoltaic Theory and Modeling Los AlamosAerosol. |] a -" m

Note: This page contains sample records for the topic "models assessing surface" 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

Assessment of reduced mechanisms using One Dimensional Stochastic Turbulence model  

E-Print Network [OSTI]

turbulence model for a syngas jet flame. Proceeding of FallKerstein 2002), a turbulent syngas (CO/H2/NO) jet flame wasand DNS results of the syngas jet flame was recently done

Chien, Li-Chun

2010-01-01T23:59:59.000Z

202

Inverse modeling of CO2 sources and sinks using satellite observations of CO2 from TES and surface flask measurements  

SciTech Connect (OSTI)

We infer CO2 surface fluxes using satellite observations of mid-tropospheric CO2 from the Tropospheric Emission Spectrometer (TES) and measurements of CO2 from surface flasks in a time-independent inversion analysis based on the GEOS-Chem model. Using TES CO2 observations over oceans, spanning 40 S 40 N, we find that the horizontal and vertical coverage of the TES and flask data are complementary. This complementarity is demonstrated by combining the datasets in a joint inversion, which provides better constraints than from either dataset alone, when a posteriori CO2 distributions are evaluated against independent ship and aircraft CO2 data. In particular, the joint inversion offers improved constraints in the tropics where surface measurements are sparse, such as the tropical forests of South America. Aggregating the annual surface-to-atmosphere fluxes from the joint inversion for the year 2006 yields 1.13 0.21 PgC for the global ocean, 2.77 0.20 PgC for the global land biosphere and 3.90 0.29 PgC for the total global natural flux (defined as the sum of all biospheric, oceanic, and biomass burning contributions but excluding CO2 emissions from fossil fuel combustion). These global ocean and global land fluxes are shown to be near the median of the broad range of values from other inversion results for 2006. To achieve these results, a bias in TES CO2 in the Southern Hemisphere was assessed and corrected using aircraft flask data, and we demonstrate that our results have low sensitivity to variations in the bias correction approach. Overall, this analysis suggests that future carbon data assimilation systems can benefit by integrating in situ and satellite observations of CO2 and that the vertical information provided by satellite observations of mid-tropospheric CO2 combined with measurements of surface CO2, provides an important additional constraint for flux inversions.

Nassar, Ray [University of Toronto; Jones, DBA [University of Toronto; Kulawik, SS [Jet Propulsion Laboratory, Pasadena, CA; Worden, JR [Jet Propulsion Laboratory, Pasadena, CA; Bowman, K [Jet Propulsion Laboratory, Pasadena, CA; Andres, Robert Joseph [ORNL; Suntharalingam, P [University of East Anglia, Norwich, United Kingdom; Chen, j. [University of Toronto; Brenninkmeijer, CAM [Max Planck Institut fur Chemie, Mainz; Schuck, TJ [Max Planck Institut fur Chemie, Mainz; Conway, T.J. [NOAA, Boulder, CO; Worthy, DE [Environment Canada

2011-01-01T23:59:59.000Z

203

A comparison of radiological risk assessment models: Risk assessment models used by the BEIR V Committee, UNSCEAR, ICRP, and EPA (for NESHAP)  

SciTech Connect (OSTI)

Radiological risk assessments and resulting risk estimates have been developed by numerous national and international organizations, including the National Research Council`s fifth Committee on the Biological Effects of Ionizing Radiations (BEIR V), the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), and the International Commission on Radiological Protection (ICRP). A fourth organization, the Environmental Protection Agency (EPA), has also performed a risk assessment as a basis for the National Emission Standards for Hazardous Air Pollutants (NESHAP). This paper compares the EPA`s model of risk assessment with the models used by the BEIR V Committee, UNSCEAR, and ICRP. Comparison is made of the values chosen by each organization for several model parameters: populations used in studies and population transfer coefficients, dose-response curves and dose-rate effects, risk projection methods, and risk estimates. This comparison suggests that the EPA has based its risk assessment on outdated information and that the organization should consider adopting the method used by the BEIR V Committee, UNSCEAR, or ICRP.

Wahl, L.E.

1994-03-01T23:59:59.000Z

204

Surface Modes of Vibration in Rigid-Ion Model of Nacl  

E-Print Network [OSTI]

SURFACE MEAN-SQUARE AMPLITUDES OF VIBRATION FOR NaC1 627 A78 (1965). A. A. Lucas, J. Chem. Phys. 48, 3156 (1968). Benson and co-workers have found that oversimplified models which allow different displacements for different ions tend... and T. Paakkari, Acta Cryst. ~23 1107 (1967). PHYSICAL REVIEW B VOLUME 6, NUMBER 2 15 JULY 1972 Surface Modes of Vibration in the Rigid-Ion Model of NaC1~ T. S. Chen, G. P. Alldredge, and F. W. de Wette Department of Physics, University of Texas...

CHEN, TS; Allen, Roland E.; Alldredg, GP; WETTE, FWD.

1972-01-01T23:59:59.000Z

205

A surface renewal model to analyze infrared image sequences of the ocean surface for the study of air-sea heat  

E-Print Network [OSTI]

A surface renewal model to analyze infrared image sequences of the ocean surface for the study of air-sea heat and gas exchange C. S. Garbe Interdisciplinary Center for Scientific Computing renewal, the net heat flux, and the heat transfer velocity during nighttime. The techniques are based

Garbe, Christoph S.

206

Geometric effects modelling for the PJM interconnection system. Part 1; Earth surface potentials computation  

SciTech Connect (OSTI)

This paper describes an ionospheric source current model and development of an earth resistivity model used to calculate geomagnetic induced currents (GIC) on the Pennsylvania-New Jersey-Maryland Interconnection (PJM). Ionospheric current is modelled as a gaussian distributed current sheet above the earth. Geological details are included by dividing the PJM service area into 11 different earth resistivity regions. The resulting earth surface potential (ESP) at each power system substation is then calculated. A companion paper describes how this ESP is applied to the power system model to calculate the geomagnetic induced current in the power system equipment and facilities.

Towle, J.N. (Diversified EM, Seattle, WA (US)); Prabhakara, F.S. (Power Technologies, Inc., Schenectady, NY (US)); Ponder, J.Z. (PJM Interconnection, Norristown, PA (US))

1992-07-01T23:59:59.000Z

207

Towards an assessment of skill acquisition in student modelling  

E-Print Network [OSTI]

/her operational skill in dynamic and highly risky domains, such as Air Traffic Control, nuclear plant operations,leila]@cmis.csiro.au Abstract: This paper presents an approach to student modelling in the context of a simulation-based ITS of the expertise. Examples are given in the domain of Air Traffic Control simulation training for conflict

Yacef, Kalina

208

Random Forest-Based Protein Model Quality Assessment (RFMQA) Using Structural Features and Potential Energy  

E-Print Network [OSTI]

Random Forest-Based Protein Model Quality Assessment (RFMQA) Using Structural Features and Potential Energy Terms Balachandran Manavalan, Juyong Lee, Jooyoung Lee* Center for In Silico Protein in protein structure prediction. In this study, we present the first application of random forest based model

Lee, Jooyoung

209

A flow resistance model for assessing the impact of vegetation on flood routing mechanics  

E-Print Network [OSTI]

control in urban storm water runoff [Kirby et al., 2005], and linking tidal hydrodynamic forcing to flow and field studies. The proposed model asymptotically recovers the flow resistance formulation when the waterA flow resistance model for assessing the impact of vegetation on flood routing mechanics Gabriel G

Katul, Gabriel

210

An Assessment of Converter Modelling Needs for Offshore Wind Power Plants Connected via VSC-  

E-Print Network [OSTI]

An Assessment of Converter Modelling Needs for Offshore Wind Power Plants Connected via VSC- HVDC high voltage direct current (HVDC) transmission is technically superior to other technologies of such complex devices. This paper presents an investigation of the modelling requirements of the MMCC HVDC

Bak, Claus Leth

211

Assessment of Transition Model and CFD Methodology for Wind Turbine Flows  

E-Print Network [OSTI]

as fossil fuels are replaced by renewable alternatives. In the U.S., the Department of Energy has publishedAssessment of Transition Model and CFD Methodology for Wind Turbine Flows Aniket C. Aranake Vinod K Navier Stokes (RANS) solver with a transition model is performed for wind turbine applications

Alonso, Juan J.

212

Update and assessment of geothermal economic models, geothermal fluid flow and heat distribution models, and geothermal data bases  

SciTech Connect (OSTI)

Numerical simulation models and data bases that were developed for DOE as part of a number of geothermal programs have been assessed with respect to their overall stage of development and usefulness. This report combines three separate studies that focus attention upon: (1) economic models related to geothermal energy; (2) physical geothermal system models pertaining to thermal energy and the fluid medium; and (3) geothermal energy data bases. Computerized numerical models pertaining to the economics of extracting and utilizing geothermal energy have been summarized and catalogued with respect to their availability, utility and function. The 19 models that are discussed in detail were developed for use by geothermal operators, public utilities, and lending institutions who require a means to estimate the value of a given resource, total project costs, and the sensitivity of these values to specific variables. A number of the models are capable of economically assessing engineering aspects of geothermal projects. Computerized simulations of heat distribution and fluid flow have been assessed and are presented for ten models. Five of the models are identified as wellbore simulators and five are described as reservoir simulators. Each model is described in terms of its operational characteristics, input, output, and other pertinent attributes. Geothermal energy data bases are reviewed with respect to their current usefulness and availability. Summaries of eight data bases are provided in catalogue format, and an overall comparison of the elements of each data base is included.

Kenkeremath, D. (ed.)

1985-05-01T23:59:59.000Z

213

A viscoplasticity model with an enhanced control of the yield surface distortion  

E-Print Network [OSTI]

A new model of metal viscoplasticity, which takes combined isotropic, kinematic, and distortional hardening into account, is presented. The basic modeling assumptions are illustrated using a new two-dimensional rheological analogy. This demonstrative rheological model is used as a guideline for the construction of constitutive relations. The nonlinear kinematic hardening is captured using the well-known Armstrong-Frederick approach. The distortion of the yield surface is described with the help of a so-called distortional backstress. A distinctive feature of the model is that any smooth convex saturated form of the yield surface which is symmetric with respect to the loading direction can be captured. In particular, an arbitrary sharpening of the saturated yield locus in the loading direction combined with a flattening on the opposite side can be covered. Moreover, the yield locus evolves smoothly and its convexity is guaranteed at each hardening stage. A strict proof of the thermodynamic consistency is provi...

Shutov, A V

2012-01-01T23:59:59.000Z

214

The structure of the free energy surface of coarse-grained off-lattice protein models  

E-Print Network [OSTI]

We have performed multicanonical simulations of hydrophobic-hydrophilic heteropolymers with a simple effective, coarse-grained off-lattice model to study the structure and the topology of the energy surface. The multicanonical method samples the whole rugged energy landscape, in particular the low-energy part, and enables one to better understand the critical behaviors and visualize the folding pathways of the considered protein model.

E. Akturk; H. Arkin Olgar; T. Celik

2007-03-23T23:59:59.000Z

215

Simulation of ultrasonic surface waves with multi-Gaussian and point source beam models  

SciTech Connect (OSTI)

In the past decade, multi-Gaussian beam models have been developed to solve many complicated bulk wave propagation problems. However, to date those models have not been extended to simulate the generation of Rayleigh waves. Here we will combine Gaussian beams with an explicit high frequency expression for the Rayleigh wave Green function to produce a three-dimensional multi-Gaussian beam model for the fields radiated from an angle beam transducer mounted on a solid wedge. Simulation results obtained with this model are compared to those of a point source model. It is shown that the multi-Gaussian surface wave beam model agrees well with the point source model while being computationally much more efficient.

Zhao, Xinyu [Center for NDE, Iowa State University, Ames, IA, 50011, USA and Dept. of Mechanical Eng., Beijing Institute of Technology, Beijing, 100081 (China); Schmerr, Lester W. Jr.; Li, Xiongbing [Center for NDE, Iowa State University, Ames, IA, 50011 (United States); Sedov, Alexander [Dept. of Mechanical Eng., Lakehead University, Thunder Bay, ON (Canada)

2014-02-18T23:59:59.000Z

216

The effect of soil hydraulic properties vs. soil texture in land surface models  

E-Print Network [OSTI]

depths in the soil column controls the partitioning of the two key energy fluxes of concern in climateThe effect of soil hydraulic properties vs. soil texture in land surface models E. D. Gutmann and E and difficulties in scaling existing data. In particular, the spatial distribution of Soil Hydraulic Properties

Small, Eric

217

Shell Model Dynamics of HCl on the MgO(001) Surface Terrace Andreas Markmann,1  

E-Print Network [OSTI]

are then used to aid the analysis of MD calculations. After equilibrium dynamics, a sudden excitation of the OH of molecular dynamics using specially tailored laser fields. The reaction of hydrogen chloride moleculesShell Model Dynamics of HCl on the MgO(001) Surface Terrace Andreas Markmann,1 Jacob L. Gavartin,2

Markmann, Andreas

218

The influence of the land surface on hydrometeorology and ecology: new advances from modeling and satellite  

E-Print Network [OSTI]

Resolution Imaging Spectroradiometer (MODIS) and EOS Advanced Microwave Scanning Radiometer (AMSR and through model initialization of soil moisture from High Resolution Land Data Assimilation System (HRLDAS moisture and sensible heat fluxes. For example, the variations of surface energy and moisture fluxes

Small, Eric

219

Developing a TeraGrid Based Land Surface Hydrology and Weather Modeling Interface  

E-Print Network [OSTI]

Developing a TeraGrid Based Land Surface Hydrology and Weather Modeling Interface Hsin-I Chang1 iclimate@purdue.edu -------------------- -------------------- 1 INTRODUCTION Real world hydrologic cyberinfrastructure (CI) has been articulated in many workshops and meetings of the environmental and hydrologic

Jiang, Wen

220

Effect of One-Dimensional Field Data Assimilation on Land Surface Model Flux Estimates with Implications  

E-Print Network [OSTI]

.W. Western1 1 Department of Civil and Environmental Engineering, The University of Melbourne, Victoria, Australia 2 CSIRO Marine and Atmospheric Research, Aspendale, Victoria, Australia Email: r Model (CBM) represent the exchange of energy and water between the earth's surface and lower atmosphere

Walker, Jeff

Note: This page contains sample records for the topic "models assessing surface" 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

SURFACE ELASTICITY MODELS FOR STATIC AND DYNAMIC RESPONSE OF NANOSCALE BEAMS  

E-Print Network [OSTI]

SURFACE ELASTICITY MODELS FOR STATIC AND DYNAMIC RESPONSE OF NANOSCALE BEAMS by Chang Liu B) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) February 2010 © Chang Liu, 2010 #12;ii Abstract Nanoscale beam of nanoscale beams. The objective is to provide NEMS designers with an efficient set of tools that can predict

Phani, A. Srikantha

222

REGION-BASED ACTIVE SURFACE MODELLING AND ALPHA MATTING FOR UNSUPERVISED TUMOUR SEGMENTATION IN PET  

E-Print Network [OSTI]

REGION-BASED ACTIVE SURFACE MODELLING AND ALPHA MATTING FOR UNSUPERVISED TUMOUR SEGMENTATION IN PET University, UK. 3. Adobe Systems, Seattle, USA. 4. Turku PET Center and Department of Oncology imaging. We have validated our method on real PET images of head-and-neck cancer patients as well

Wang, Jue

223

Control of surface gravity waves by variable fluid injection in a model of a copper  

E-Print Network [OSTI]

Control of surface gravity waves by variable fluid injection in a model of a copper converter splashing appears in copper converters when air is injected into the molten matte in order to carry out to the opposite extreme to where the nozzle injection is placed. Key words: Copper converter, gravity waves

Osses, Axel

224

Risk-based modelling of surface water quality: a case study of the Charles River, Massachusetts  

E-Print Network [OSTI]

: Water quality; Risk; Monte Carlo; Sensitivity analysis; Eutrophication 1. Introduction 1.1. Motivation recognised in the development of some decision-support tools, for example, QUAL2E- UNCAS (Brown and BarnwellRisk-based modelling of surface water quality: a case study of the Charles River, Massachusetts

Wagener, Thorsten

225

Surface kinetics and plasma equipment model for Si etching by fluorocarbon plasmas  

E-Print Network [OSTI]

Surface kinetics and plasma equipment model for Si etching by fluorocarbon plasmas Da Zhanga of fluorocarbon radicals on the reactor walls, polymer erosion rates and F atom diffusion through the polymer during Si etching using fluorocarbon gases in an induc- tively coupled plasma ICP reactor.4 They observed

Kushner, Mark

226

A FETCH DEPENDENT MODEL OF SEA SURFACE ROUGHNESS FOR OFFSHORE WIND POWER UTILISATION  

E-Print Network [OSTI]

, Resources, Roughness, Coastal Sea Areas, Waves, Rødsand 1 INTRODUCTION Large offshore wind farms are beingA FETCH DEPENDENT MODEL OF SEA SURFACE ROUGHNESS FOR OFFSHORE WIND POWER UTILISATION Bernhard Lange wind conditions of offshore sites, since the higher energy yield has to compensate the additional

Heinemann, Detlev

227

Inferring surface heat flux distributions guided by a global seismic model: particular application to Antarctica  

E-Print Network [OSTI]

-flow measurements are rare or entirely absent. This will result in a smooth global heat-flow map that may proveInferring surface heat flux distributions guided by a global seismic model: particular application to Antarctica Nikolai M. Shapiro*, Michael H. Ritzwoller Department of Physics, Center for Imaging the Earth

Shapiro, Nikolai

228

A Preliminary Study to Assess Model Uncertainties in Fluid Flows  

E-Print Network [OSTI]

of the fluid. ? The sound speed, c, is assumed to be constant even if it usually depends on the temperature and the pressure. This is a good approximation for liquids but not for gases. The sound speed is reactor-dependent. ? The Equation Of State (EOS... to the temperature. This parameter is assumed constant in this model. 7 ? ???P is the dilatation of the density due to the pressure. This parameter is also assumed constant but is different for different sound speeds. Its expression is as follows: ?? ?P = 1...

Delchini, Marc Olivier

2011-08-08T23:59:59.000Z

229

Review and perspectives on spallings release models in the 1996 performance assessment for the Waste Isolation Pilot Plant  

SciTech Connect (OSTI)

The Waste Isolation Pilot Plant was licensed for disposal of transuranic wastes generated by the US Department of Energy. The facility consists of a repository mined in a bedded salt formation, approximately 650 m below the surface. Regulations promulgated by the US Environmental Protection Agency require that performance assessment calculations for the repository include the possibility that an exploratory drilling operation could penetrate the waste disposal areas at some time in the future. Release of contaminated solids could reach the surface during a drilling intrusion. One of the mechanisms for release, known as spallings, can occur if gas pressures in the repository exceed the hydrostatic pressure of a column of drilling mud. Calculation of solids releases for spallings depends critically on the conceptual models for the waste, for the spallings process, and assumptions regarding driller parameters and practices. The paper presents a review of the evolution of these models during regulatory review of the Compliance Certification Application for the repository. A summary and perspectives on the implementation of conservative assumptions in model development are also provided.

Knowles, M.K; Hansen, F.D.; Thompson, T.W.; Schatz, J.F.; Gross, M.

2000-05-22T23:59:59.000Z

230

Improvement of modelling capabilities for assessing urban contamination : The EMRAS Urban Remediation Working Group.  

SciTech Connect (OSTI)

The Urban Remediation Working Group of the International Atomic Energy Agency's Environmental Modeling for Radiation Safety (EMRAS) programme was established to improve modeling and assessment capabilities for radioactively contaminated urban situations, including the effects of countermeasures. An example of the Working Group's activities is an exercise based on Chernobyl fallout data in Ukraine, which has provided an opportunity to compare predictions among several models and with available measurements, to discuss reasons for discrepancies, and to identify areas where additional information would be helpful.

Thiessen, K. M.; Batandjieva, B.; Andersson, K. G.; Arkhipov, A.; Charnock, T. W.; Gallay, F.; Gaschak, S.; Golikov, V.; Hwang, W. T.; Kaiser, J. C.; Kamboj, S.; Steiner, M.; Tomas, J.; Trifunovic, D.; Yu, C.; Ziemer, R. L.; Zlobenko, B.; Environmental Science Division; SENES Oak Ridge; IAEA; Riso National Lab.; Chernobyl Center for Nuclear Safety; Health Protection Agency; IRSN; Inst. of Radiation Hygene of the Ministry of Public Health, Russian Federation; KAERI, Republic of Korea; GSF, Germany; BfS, Germany; CPHR, Cuba; State Office for Radiation Protection, Croatia; AECL, Canada; National Academy of Science, Ukraine

2008-01-01T23:59:59.000Z

231

Comparative evaluation of life cycle assessment models for solid waste management  

SciTech Connect (OSTI)

This publication compares a selection of six different models developed in Europe and America by research organisations, industry associations and governmental institutions. The comparison of the models reveals the variations in the results and the differences in the conclusions of an LCA study done with these models. The models are compared by modelling a specific case - the waste management system of Dresden, Germany - with each model and an in-detail comparison of the life cycle inventory results. Moreover, a life cycle impact assessment shows if the LCA results of each model allows for comparable and consecutive conclusions, which do not contradict the conclusions derived from the other models' results. Furthermore, the influence of different level of detail in the life cycle inventory of the life cycle assessment is demonstrated. The model comparison revealed that the variations in the LCA results calculated by the models for the case show high variations and are not negligible. In some cases the high variations in results lead to contradictory conclusions concerning the environmental performance of the waste management processes. The static, linear modelling approach chosen by all models analysed is inappropriate for reflecting actual conditions. Moreover, it was found that although the models' approach to LCA is comparable on a general level, the level of detail implemented in the software tools is very different.

Winkler, Joerg [Institute for Waste Management and Contaminated Sites Treatment, TU Dresden Faculty of Forestry, Geo and Hydro Sciences, Pratzschwitzer Str. 15, 01796 Pirna (Germany); Bilitewski, Bernd [Institute for Waste Management and Contaminated Sites Treatment, TU Dresden Faculty of Forestry, Geo and Hydro Sciences, Pratzschwitzer Str. 15, 01796 Pirna (Germany)], E-mail: abfall@rcs.urz.tu-dresden.de

2007-07-01T23:59:59.000Z

232

Surface Complexation Model for Strontium Sorption to Amorphous Silica and Goethite  

SciTech Connect (OSTI)

Strontium sorption to amorphous silica and goethite was measured as a function of pH and dissolved strontium and carbonate concentrations at 25 C. Strontium sorption gradually increases from 0 to 100% from pH 6 to 10 for both phases and requires multiple outer-sphere surface complexes to fit the data. All data are modeled using the triple layer model and the site-occupancy standard state; unless stated otherwise all strontium complexes are mononuclear. Strontium sorption to amorphous silica in the presence and absence of dissolved carbonate can be fit with tetradentate Sr{sup 2+} and SrOH{sup +} complexes on the {beta}-plane and a monodentate Sr{sup 2+} complex on the diffuse plane to account for strontium sorption at low ionic strength. Strontium sorption to goethite in the absence of dissolved carbonate can be fit with monodentate and tetradentate SrOH{sup +} complexes and a tetradentate binuclear Sr{sup 2+} species on the {beta}-plane. The binuclear complex is needed to account for enhanced sorption at high strontium surface loadings. In the presence of dissolved carbonate additional monodentate Sr{sup 2+} and SrOH{sup +} carbonate surface complexes on the {beta}-plane are needed to fit strontium sorption to goethite. Modeling strontium sorption as outer-sphere complexes is consistent with quantitative analysis of extended X-ray absorption fine structure (EXAFS) on selected sorption samples that show a single first shell of oxygen atoms around strontium indicating hydrated surface complexes at the amorphous silica and goethite surfaces. Strontium surface complexation equilibrium constants determined in this study combined with other alkaline earth surface complexation constants are used to recalibrate a predictive model based on Born solvation and crystal-chemistry theory. The model is accurate to about 0.7 log K units. More studies are needed to determine the dependence of alkaline earth sorption on ionic strength and dissolved carbonate and sulfate concentrations for the development of a robust surface complexation database to estimate alkaline earth sorption in the environment.

Carroll, S; Robers, S; Criscenti, L; O'Day, P

2007-11-30T23:59:59.000Z

233

Assimilation of surface data in a one-dimensional physical-biogeochemical model of the surface ocean: 2. Adjusting a simple trophic model to chlorophyll, temperature, nitrate, and pCO{sub 2} data  

SciTech Connect (OSTI)

This paper builds on a previous work which produced a constrained physical-biogeochemical model of the carbon cycle in the surface ocean. Three issues are addressed: (1) the results of chlorophyll assimilation using a simpler trophic model, (2) adjustment of parameters using the simpler model and data other than surface chlorophyll concentrations, and (3) consistency of the main carbon fluxes derived by the simplified model with values from the more complex model. A one-dimensional vertical model coupling the physics of the ocean mixed layer and a description of biogeochemical processes with a simple trophic model was used to address these issues. Chlorophyll concentration, nitrate concentration, and temperature were used to constrain the model. The surface chlorophyll information was shown to be sufficient to constrain primary production within the photic layer. The simultaneous assimilation of chlorophyll, nitrate, and temperature resulted in a significant improvement of model simulation for the data used. Of the nine biological and physical parameters which resulted in significant variations of the simulated chlorophyll concentration, seven linear combinations of the mode parameters were constrained. The model fit was an improvement on independent surface chlorophyll and nitrate data. This work indicates that a relatively simple biological model is sufficient to describe carbon fluxes. Assimilation of satellite or climatological data coulc be used to adjust the parameters of the model for three-dimensional models. It also suggests that the main carbon fluxes driving the carbon cycle within surface waters could be derived regionally from surface information. 38 refs., 16 figs., 7 tabs.

Prunet, P.; Minster, J.F.; Echevin, V. [Laboratoire CNES-CNRS, Toulouse (France)] [and others] [Laboratoire CNES-CNRS, Toulouse (France); and others

1996-03-01T23:59:59.000Z

234

Planetary boundary layer depth in Global climate models induced biases in surface climatology  

E-Print Network [OSTI]

The Earth has warmed in the last century with the most rapid warming occurring near the surface in the arctic. This enhanced surface warming in the Arctic is partly because the extra heat is trapped in a thin layer of air near the surface due to the persistent stable-stratification found in this region. The warming of the surface air due to the extra heat depends upon the amount of turbulent mixing in the atmosphere, which is described by the depth of the atmospheric boundary layer (ABL). In this way the depth of the ABL determines the effective response of the surface air temperature to perturbations in the climate forcing. The ABL depth can vary from tens of meters to a few kilometers which presents a challenge for global climate models which cannot resolve the shallower layers. Here we show that the uncertainties in the depth of the ABL can explain up to 60 percent of the difference between the simulated and observed surface air temperature trends and 50 percent of the difference in temperature variability...

Davy, Richard

2014-01-01T23:59:59.000Z

235

Modeling and Simulation of Long-Term Performance of Near-Surface Barriers  

SciTech Connect (OSTI)

Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone's back yard); most of these storage sites include a surface barrier (cap) to prevent migration of the waste due to infiltration of surface water. The design lifespan for such barriers ranges from 30 to 1000 years, depending on hazard and regulations. In light of historical performance, society needs a better basis for predicting barrier performance over long time periods and tools for optimizing maintenance of barriers while in service. We believe that, as in other industries, better understanding of the dynamics of barrier system degradation will enable improved barriers (cheaper, longer-lived, simpler, easier to maintain) and improved maintenance. We are focusing our research on earthen caps, especially those with evapo-transpiration and capillary breaks. Typical cap assessments treat the barrier's structure as static prior to some defined lifetime. Environmental boundary conditions such as precipitation and temperature are treated as time dependent. However, other key elements of the barrier system are regarded as constant, including engineered inputs (e.g., fire management strategy, irrigation, vegetation control), surface ecology (critical to assessment of plant transpiration), capillary break interface, material properties, surface erosion rate, etc. Further, to be conservative, only harmful processes are typically considered. A more holistic examination of both harmful and beneficial processes will provide more realistic pre-service prediction and in-service assessment of performance as well as provide designers a tool to encourage beneficial processes while discouraging harmful processes. Thus, the INEEL started a new project on long-term barrier integrity in April 2002 that aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late, prior to system-level failure). This paper describes our computer simulation approach for better understanding the relationships and dynamics between the various components and management decisions in a cap. The simulation is designed to clarify the complex relationships between the various components within the cap system and the various management practices that affect the barrier performance. We have also conceptualized a time-dependent 3-D simulation with rigorous solution to unsaturated flow physics with complex surface boundary conditions.

Piet, S. J.; Jacobson, J. J.; Martian, P.; Martineau, R.; Soto, R.

2003-02-25T23:59:59.000Z

236

Modeling and Simulation of Long-Term Performance of Near-Surface Barriers  

SciTech Connect (OSTI)

Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone’s back yard); most of these storage sites include a surface barrier (cap) to prevent migration of the waste due to infiltration of surface water. The design lifespan for such barriers ranges from 30 to 1000 years, depending on hazard and regulations. In light of historical performance, society needs a better basis for predicting barrier performance over long time periods and tools for optimizing maintenance of barriers while in service. We believe that, as in other industries, better understanding of the dynamics of barrier system degradation will enable improved barriers (cheaper, longer-lived, simpler, easier to maintain) and improved maintenance. We are focusing our research on earthen caps, especially those with evapo-transpiration and capillary breaks. Typical cap assessments treat the barrier’s structure as static prior to some defined lifetime. Environmental boundary conditions such as precipitation and temperature are treated as time dependent. However, other key elements of the barrier system are regarded as constant, including engineered inputs (e.g., fire management strategy, irrigation, vegetation control), surface ecology (critical to assessment of plant transpiration), capillary break interface, material properties, surface erosion rate, etc. Further, to be conservative, only harmful processes are typically considered. A more holistic examination of both harmful and beneficial processes will provide more realistic pre-service prediction and in-service assessment of performance as well as provide designers a tool to encourage beneficial processes while discouraging harmful processes. Thus, the INEEL started a new project on long-term barrier integrity in April 2002 that aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late, prior to system-level failure). This paper describes our computer simulation approach for better understanding the relationships and dynamics between the various components and management decisions in a cap. The simulation is designed to clarify the complex relationships between the various components within the cap system and the various management practices that affect the barrier performance. We have also conceptualized a time-dependent 3-D simulation with rigorous solution to unsaturated flow physics with complex surface boundary conditions.

Piet, Steven James; Jacobson, Jacob Jordan; Soto, Rafael; Martian, Pete; Martineau, Richard Charles

2003-02-01T23:59:59.000Z

237

Computational Modeling and Assessment Of Nanocoatings for Ultra Supercritical Boilers  

SciTech Connect (OSTI)

Forced outages and boiler unavailability in conventional coal-fired fossil power plants is most often caused by fireside corrosion of boiler waterwalls. Industry-wide, the rate of wall thickness corrosion wastage of fireside waterwalls in fossil-fired boilers has been of concern for many years. It is significant that the introduction of nitrogen oxide (NOx) emission controls with staged burners systems has increased reported waterwall wastage rates to as much as 120 mils (3 mm) per year. Moreover, the reducing environment produced by the low-NOx combustion process is the primary cause of accelerated corrosion rates of waterwall tubes made of carbon and low alloy steels. Improved coatings, such as the MCrAl nanocoatings evaluated here (where M is Fe, Ni, and Co), are needed to reduce/eliminate waterwall damage in subcritical, supercritical, and ultra-supercritical (USC) boilers. The first two tasks of this six-task project-jointly sponsored by EPRI and the U.S. Department of Energy (DE-FC26-07NT43096)-have focused on computational modeling of an advanced MCrAl nanocoating system and evaluation of two nanocrystalline (iron and nickel base) coatings, which will significantly improve the corrosion and erosion performance of tubing used in USC boilers. The computational model results showed that about 40 wt.% is required in Fe based nanocrystalline coatings for long-term durability, leading to a coating composition of Fe-25Cr-40Ni-10 wt.% Al. In addition, the long term thermal exposure test results further showed accelerated inward diffusion of Al from the nanocrystalline coatings into the substrate. In order to enhance the durability of these coatings, it is necessary to develop a diffusion barrier interlayer coating such TiN and/or AlN. The third task 'Process Advanced MCrAl Nanocoating Systems' of the six-task project jointly sponsored by the Electric Power Research Institute, EPRI and the U.S. Department of Energy (DE-FC26-07NT43096)- has focused on processing of advanced nanocrystalline coating systems and development of diffusion barrier interlayer coatings. Among the diffusion interlayer coatings evaluated, the TiN interlayer coating was found to be the optimum one. This report describes the research conducted under the Task 3 workscope.

David W. Gandy; John P. Shingledecker

2011-04-11T23:59:59.000Z

238

hal-00272925,version1-14Apr2008 SURFACE TENSION IN THE DILUTE ISING MODEL. THE WULFF  

E-Print Network [OSTI]

hal-00272925,version1-14Apr2008 SURFACE TENSION IN THE DILUTE ISING MODEL. THE WULFF CONSTRUCTION. MARC WOUTS Abstract. We study the surface tension and the phenomenon of phase coexistence for the Ising respect to random couplings) of surface tension and analyze its large deviations : upper deviations occur

Paris-Sud XI, Université de

239

Response Surface Energy Modeling of an Electric Vehicle over a Reduced Composite Drive Cycle  

SciTech Connect (OSTI)

Response surface methodology (RSM) techniques were applied to develop a predictive model of electric vehicle (EV) energy consumption over the Environmental Protection Agency's (EPA) standardized drive cycles. The model is based on measurements from a synthetic composite drive cycle. The synthetic drive cycle is a minimized statistical composite of the standardized urban (UDDS), highway (HWFET), and US06 cycles. The composite synthetic drive cycle is 20 minutes in length thereby reducing testing time of the three standard EPA cycles by over 55%. Vehicle speed and acceleration were used as model inputs for a third order least squared regression model predicting vehicle battery power output as a function of the drive cycle. The approach reduced three cycles and 46 minutes of drive time to a single test of 20 minutes. Application of response surface modeling to the synthetic drive cycle is shown to predict energy consumption of the three EPA cycles within 2.6% of the actual measured values. Additionally, the response model may be used to predict energy consumption of any cycle within the speed/acceleration envelope of the synthetic cycle. This technique results in reducing test time, which additionally provides a model that may be used to expand the analysis and understanding of the vehicle under consideration.

Jehlik, Forrest [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); LaClair, Tim J [ORNL] [ORNL

2014-01-01T23:59:59.000Z

240

Development of High Resolution Land Surface Parameters for the Community Land Model  

SciTech Connect (OSTI)

There is a growing need for high-resolution land surface parameters as land surface models are being applied at increasingly higher spatial resolution offline as well as in regional and global models. The default land surface parameters for the most recent version of the Community Land Model (i.e. CLM 4.0) are at 0.5° or coarser resolutions, released with the Community Earth System Model (CESM). Plant Functional Types (PFTs), vegetation properties such as Leaf Area Index (LAI), Stem Area Index (SAI), and non-vegetated land covers were developed using remotely sensed datasets retrieved in late 1990’s and the beginning of this century. In this study, we developed new land surface parameters for CLM 4.0, specifically PFTs, LAI, SAI and non-vegetated land cover composition, at 0.05° resolution globally based on the most recent MODIS land cover and improved MODIS LAI products. Compared to the current CLM 4.0 parameters, the new parameters produced a decreased coverage by bare soil and trees, but an increased coverage by shrub, grass, and cropland. The new parameters result in a decrease in global seasonal LAI, with the biggest decrease in boreal forests; however, the new parameters also show a large increase in LAI in tropical forest. Differences between the new and the current parameters are mainly caused by changes in the sources of remotely sensed data and the representation of land cover in the source data. Advantages and disadvantages of each dataset were discussed in order to provide guidance on the use of the data. The new high-resolution land surface parameters have been used in a coupled land-atmosphere model (WRF-CLM) applied to the western U.S. to demonstrate their use in high-resolution modeling. A remapping method from the latitude/longitude grid of the CLM data to the WRF grids with map projection was also demonstrated. Future work will include global offline CLM simulations to examine the impacts of source data resolution and subsequent land parameter changes on simulated land surface processes.

Ke, Yinghai; Leung, Lai-Yung R.; Huang, Maoyi; Coleman, Andre M.; Li, Hongyi; Wigmosta, Mark S.

2012-11-06T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" 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

Modified two-fluid model of conductivity for superconducting surface resistance calculation. Master's thesis  

SciTech Connect (OSTI)

The traditional two-fluid model of superconducting conductivity was modified to make it accurate, while remaining fast, for designing and simulating microwave devices. The modification reflects the BCS coherence effects in the conductivity of a superconductor, and is incorporated through the ratio of normal to superconducting electrons. This modified ratio is a simple analytical expression which depends on frequency, temperature and material parameters. This modified two-fluid model allows accurate and rapid calculation of the microwave surface impedance of a superconductor in the clean and dirty limits and in the weak- and strong-coupled regimes. The model compares well with surface resistance data for Nb and provides insight into Nb3Sn and Y1Ba2Cu3O(7-delta). Numerical calculations with the modified two-fluid model are an order of magnitude faster than the quasi-classical program by Zimmermann (1), and two to five orders of magnitude faster than Halbritter's BCS program (2) for surface resistance.

Linden, D.S.

1993-05-01T23:59:59.000Z

242

Theoretical model for methanol formation from CO and H/sub 2/ on zinc oxide surfaces  

SciTech Connect (OSTI)

Models are developed for the polar (0001) and nonpolar (1010) surfaces of ZnO in order to consider methanol formation from adsorbed carbon monoxide and hydrogen atoms. The heats of adsorption of H/sub x/CO and OH/sub x/CO (x = 0-3) species involved in methanol formation are computed to determine the enthalpy changes of reaction. Reaction sequences involving formyl or formate intermediates are considered. The reaction mechanism is catalyzed by the Cu/sup +/ to proceed through a methoxy intermediate on Cu/sup +//ZnO with a lower of the energy pathway. The ZnO surfaces are poor donors and function primarily as acceptors of electron density from CO. The donor role of Cu/sup +/ is demonstrated on the polar surface by increasing the heat of adsorption of acceptor adspecies and decreasing the heat of adsorption of donor adspecies. 22 references, 8 figures, 4 tables.

Baetzold, R.C.

1985-09-12T23:59:59.000Z

243

One-way coupling of an integrated assessment model and a water resources model: evaluation and implications of future changes over the US Midwest  

SciTech Connect (OSTI)

An integrated model is being developed to advance our understanding of the interactions between human activities, terrestrial system and water cycle, and how system interactions will be affected by a changing climate at the regional scale. As a first step towards that goal, a global integrated assessment model including a waterdemand model is coupled offline with a land surface hydrology – routing – water resources management model. A spatial and temporal disaggregation approach is developed to project the annual regional water demand simulations into a daily time step and subbasin representation. The model demonstrated reasonable ability to represent the historical flow regulation and water supply over the Midwest (Missouri, Upper Mississippi and Ohio). Implications for the future flow regulation, water supply and supply deficit are investigated using a climate change projection with the B1 emission scenario which affects both natural flow and water demand. Over the Midwest, changes in flow regulation are mostly driven by the change in natural flow due to the limited storage capacity over the Ohio and Upper Mississippi river basins. The changes in flow and demand have a combined effect on the Missouri Summer regulated flow. The supply deficit tends to be driven by the change in flow over the region. Spatial analysis demonstrates the relationship between the supply deficit and the change in demand over urban areas not along a main river or with limited storage, and over areas upstream of groundwater dependent fields with therefore overestimated demand.

Voisin, Nathalie; Liu, Lu; Hejazi, Mohamad I.; Tesfa, Teklu K.; Li, Hongyi; Huang, Maoyi; Liu, Ying; Leung, Lai-Yung R.

2013-11-18T23:59:59.000Z

244

SUMO, System performance assessment for a high-level nuclear waste repository: Mathematical models  

SciTech Connect (OSTI)

Following completion of the preliminary risk assessment of the potential Yucca Mountain Site by Pacific Northwest Laboratory (PNL) in 1988, the Office of Civilian Radioactive Waste Management (OCRWM) of the US Department of Energy (DOE) requested the Performance Assessment Scientific Support (PASS) Program at PNL to develop an integrated system model and computer code that provides performance and risk assessment analysis capabilities for a potential high-level nuclear waste repository. The system model that has been developed addresses the cumulative radionuclide release criteria established by the US Environmental Protection Agency (EPA) and estimates population risks in terms of dose to humans. The system model embodied in the SUMO (System Unsaturated Model) code will also allow benchmarking of other models being developed for the Yucca Mountain Project. The system model has three natural divisions: (1) source term, (2) far-field transport, and (3) dose to humans. This document gives a detailed description of the mathematics of each of these three divisions. Each of the governing equations employed is based on modeling assumptions that are widely accepted within the scientific community.

Eslinger, P.W.; Miley, T.B.; Engel, D.W.; Chamberlain, P.J. II

1992-09-01T23:59:59.000Z

245

Scalability of grid- and subbasin-based land surface modeling approaches for hydrologic simulations  

SciTech Connect (OSTI)

This paper investigates the relative merits of grid- and subbasin-based land surface modeling approaches for hydrologic simulations, with a focus on their scalability (i.e., abilities to perform consistently across a range of spatial resolutions) in simulating runoff generation. Simulations produced by the grid- and subbasin-based configurations of the Community Land Model (CLM) are compared at four spatial resolutions (0.125o, 0.25o, 0.5o and 1o) over the topographically diverse region of the U.S. Pacific Northwest. Using the 0.125o resolution simulation as the “reference”, statistical skill metrics are calculated and compared across simulations at 0.25o, 0.5o and 1o spatial resolutions of each modeling approach at basin and topographic region levels. Results suggest significant scalability advantage for the subbasin-based approach compared to the grid-based approach for runoff generation. Basin level annual average relative errors of surface runoff at 0.25o, 0.5o, and 1o compared to 0.125o are 3%, 4%, and 6% for the subbasin-based configuration and 4%, 7%, and 11% for the grid-based configuration, respectively. The scalability advantages of the subbasin-based approach are more pronounced during winter/spring and over mountainous regions. The source of runoff scalability is found to be related to the scalability of major meteorological and land surface parameters of runoff generation. More specifically, the subbasin-based approach is more consistent across spatial scales than the grid-based approach in snowfall/rainfall partitioning, which is related to air temperature and surface elevation. Scalability of a topographic parameter used in the runoff parameterization also contributes to improved scalability of the rain driven saturated surface runoff component, particularly during winter. Hence this study demonstrates the importance of spatial structure for multi-scale modeling of hydrological processes, with implications to surface heat fluxes in coupled land-atmosphere modeling.

Tesfa, Teklu K.; Leung, Lai-Yung R.; Huang, Maoyi; Li, Hongyi; Voisin, Nathalie; Wigmosta, Mark S.

2014-03-27T23:59:59.000Z

246

An idealised experimental model of ocean surface wave transmission by an ice floe  

E-Print Network [OSTI]

An experimental model of transmission of ocean waves by an ice floe is presented. Thin plastic plates with different material properties and thicknesses are used to model the floe. Regular incident waves with different periods and steepnesses are used, ranging from gently-sloping to storm-like conditions. A wave gauge is used to measure the water surface elevation in the lee of the floe. The depth of wave overwash on the floe is measured by a gauge in the centre of the floe's upper surface. Results show transmitted waves are regular for gently-sloping incident waves but irregular for storm-like incident waves. The proportion of the incident wave transmitted is shown to decrease as incident wave steepness increases, and to be at its minimum for an incident wavelength equal to the floe length. Further, a trend is noted for transmission to decrease as the mean wave height in the overwash region increases.

Bennetts, Luke; Meylan, Michael; Cavaliere, Claudio; Babanin, Alexander; Toffoli, Alessandro

2015-01-01T23:59:59.000Z

247

Assessment of PWR Steam Generator modelling in RELAP5/MOD2. International Agreement Report  

SciTech Connect (OSTI)

An assessment of Steam Generator (SG) modelling in the PWR thermal-hydraulic code RELAP5/MOD2 is presented. The assessment is based on a review of code assessment calculations performed in the UK and elsewhere, detailed calculations against a series of commissioning tests carried out on the Wolf Creek PWR and analytical investigations of the phenomena involved in normal and abnormal SG operation. A number of modelling deficiencies are identified and their implications for PWR safety analysis are discussed -- including methods for compensating for the deficiencies through changes to the input deck. Consideration is also given as to whether the deficiencies will still be present in the successor code RELAP5/MOD3.

Putney, J.M.; Preece, R.J. [National Power, Leatherhead (GB). Technology and Environment Centre

1993-06-01T23:59:59.000Z

248

Modeling surfaces in the context of pulsed-power : work functions, electron emission and dynamic response.  

SciTech Connect (OSTI)

The ability to quickly understand and deal with issues on ZR, or to virtually design a future ZX accelerator, requires a physics-based capability to simulate all key pulsed power components. Highly important for gas switches and transmission lines are surface phenomena: thermionic emission, photoemission, field emission, and ion-surface dynamics. These are complex processes even at normal conditions, when coupled to the dynamic environment in pulsed power components, the current state of the art of understanding is not at the level of science based predictive modeling. Modeling efforts at the macroscopic level (finite element based hydrodynamic simulations) require detailed information of these processes to yield more reliable results. This is the final report of an LDRD project in the science of extreme environments investment area; the project was focused on describing the physics of surfaces of materials of interest in pulsed-power components. We have calculated the temperature dependence of work functions for metals from first principles using density functional theory (DFT) as well as investigated the effect of initial oxidation and alloying. By using the GW method, we have gone beyond DFT to calculate work functions for Al. The GW work required base-lining the GW results for different systems, since GW lacks a description of total energy. Lastly, we investigated the more macroscopic physics of how a surface and bulk material responds to a very high current under a short time, representative for current loads in pulsed-power components, with emphasis on materials modeling. These simulations were made using two hydrodynamic codes, ALEGRA and MACH2, in order to focus on the materials models themselves.

Cochrane, Kyle Robert (Ktech Corporation, Albuquerque, NM); Chantrenne, Sophie (SAIC, Albuquerque, NM); Mattsson, Thomas Kjell Rene; Faleev, Sergey V. (SNAMI Inc., AL)

2009-09-01T23:59:59.000Z

249

The critical indices of the Quark-Gluon Bags with Surface Tension Model with tricritical endpoint  

E-Print Network [OSTI]

The critical indices \\alpha', \\beta, \\gamma' and \\delta of the Quark Gluon Bags with Surface Tension Model with the tricritical endpoint are calculated as functions of the usual parameters of this model and two newly introduces parameters (indices). They are compared with the critical exponents of other models. It is shown that for the newly introduced indices \\chi = 0 and \\xi^T < 1 there is a branch of solutions for which the critical exponents of the present model and the statistical multifragmentation model coincide, otherwise these models belong to different universality classes. It is shown that for realistic values of the parameter \\varkappa the critical exponents \\alpha', \\beta, \\gamma' and \\delta of simple liquids and 3-dimensional Ising model can be only described by the branch of solutions in which all indices except for \\alpha' correspond to their values within the statistical multifragmentation model. The scaling relations for the found critical exponents are verified and it is demonstrated that for the standard definition of the index \\alpha' the Fisher and Griffiths scaling inequalities are not fulfilled for some values of the model parameters, whereas the Liberman scaling inequality is always obeyed. Although it is shown that the specially defined index \\alpha'_s recovers the scaling relations, another possibility, an existence of the non-Fisher universality classes, is also discussed.

A. I. Ivanytskyi

2011-04-11T23:59:59.000Z

250

Solving the problem of inadequate scoring rules for assessing probabilistic football forecast models  

E-Print Network [OSTI]

Solving the problem of inadequate scoring rules for assessing probabilistic football forecast forecasting models, and the relative simplicity of the outcome of such forecasts (they require only three their forecast accuracy. Moreover, the various scoring rules used for validation in previous studies

Fenton, Norman

251

Use of models and observations to assess trends in the 19502005 water balance and climate  

E-Print Network [OSTI]

) was about 50% of normal during 2000­2001. The ensuing drought-related water shortage led to seriousUse of models and observations to assess trends in the 1950­2005 water balance and climate of Upper-driven interannual (and longer) variability is evident. Evaporation and the other components of the water balance

252

Refinement of weed risk assessments for biofuels using Camelina sativa as a model species  

E-Print Network [OSTI]

Refinement of weed risk assessments for biofuels using Camelina sativa as a model species Philip B and Environmental Sciences, Montana State University, PO Box 173120, Bozeman, MT 59717-3120, USA Summary 1. Biofuel. However, concerns have been raised on the invasiveness of biofuel feedstocks. Estimating invasion

Peterson, Robert K. D.

253

Cognitive Assessment Models with Few Assumptions, and Connections with Nonparametric IRT  

E-Print Network [OSTI]

Cognitive Assessment Models with Few Assumptions, and Connections with Nonparametric IRT Brian of the monotonicity conditions discussed in Section 4. #12;Abstract In recent years, as cognitive theories of learning" on student achievement relative to theory-driven lists of examinee skills, beliefs and other cognitive

Junker, Brian

254

Assessing Seasonal Confounding and Model Selection Bias in Air Pollution Epidemiology Using Positive and  

E-Print Network [OSTI]

July 15, 1999 #12;Abstract Much of the evidence for health e ects of particulate air pollution has come. We thus refer to the `air pollution hypothesis' to describe increased risk of health outcomes dueAssessing Seasonal Confounding and Model Selection Bias in Air Pollution Epidemiology Using

Washington at Seattle, University of

255

Ex-plant consequence assessment for NUREG-1150: Models, typical results, uncertainties  

SciTech Connect (OSTI)

The assessment of ex-plant consequences for NUREG-1150 source terms was performed using the MELCOR Accident Consequence Code System (MACCS). This paper will briefly discuss the following elements of MACCS consequence calculations: input data, phenomena modeled, computational framework, typical results, controlling phenomena, and uncertainties. Wherever possible, NUREG-1150 results will be used to illustrate the discussion. 28 refs., 14 figs., 6 tabs.

Sprung, J.L.

1987-01-01T23:59:59.000Z

256

A Multi-Model Assessment of Regional Climate Disparities Caused by Solar Geoengineering  

E-Print Network [OSTI]

1 A Multi-Model Assessment of Regional Climate Disparities Caused by Solar Geoengineering Normal University, Beijing, China. 9 School of Engineering and Applied Sciences, Harvard University levels. G1 involves a reduction in solar irradiance to counteract the radiative forcing5 in abrupt4xCO2

Robock, Alan

257

Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines  

E-Print Network [OSTI]

Turbines by Michael Robert Shives B.Eng., Carleton University, 2008 A Thesis Submitted in Partial Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines examines methods for designing and analyzing kinetic turbines based on blade element momentum (BEM) theory

Victoria, University of

258

Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines  

E-Print Network [OSTI]

Turbines by Michael Robert Shives B.Eng., Carleton University, 2008 A Dissertation Submitted in Partial Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines) #12;iii ABSTRACT This thesis examines methods for designing and analyzing kinetic turbines based

Pedersen, Tom

259

Greenland ice sheet surface mass-balance modeling in a 131-year perspective, 1950-2080  

SciTech Connect (OSTI)

Fluctuations in the Greenland Ice Sheet (GrIS) surface mass-balance (SMB) and freshwater influx to the surrounding oceans closely follow climate fluctuations and are of considerable importance to the global eustatic sea level rise. SnowModel, a state-of-the-art snow-evolution modeling system, was used to simulate variations in the GrIS melt extent, surface water balance components, changes in SMB, and freshwater influx to the ocean. The simulations are based on the IPCC scenario AlB modeled by the HIRHAM4 RCM (using boundary conditions from ECHAM5 AOGCM) from 1950 through 2080. In-situ meteorological station (GC-Net and WMO DMI) observations from inside and outside the GrIS were used to validate and correct RCM output data before it was used as input for SnowModel. Satellite observations and independent SMB studies were used to validate the SnowModel output and confirm the model's robustness. We simulated a {approx}90% increase in end-of-summer surface melt extent (0.483 x 10{sup 6} km{sup 2}) from 1950 to 2080, and a melt index (above 2,000-m elevation) increase of 138% (1.96 x 10{sup 6} km{sup 2} x days). The greatest difference in melt extent occured in the southern part of the GrIS, and the greatest changes in the number of melt days was seen in the eastern part of the GrIS ({approx}50-70%) and was lowest in the west ({approx}20-30%). The rate of SMB loss, largely tied to changes in ablation processes, lead to an enhanced average loss of 331 km{sup 3} from 1950 to 2080, an average 5MB level of -99 km{sup 3} for the period 2070-2080. GrIS surface freshwater runoff yielded an eustatic rise in sea level from 0.8 {+-} 0.1 (1950-1959) to 1.9 {+-} 0.1 mm (2070-2080) sea level equivalent (SLE) y{sup -1}. The accumulated GrIS freshwater runoff contribution from surface melting equaled 160 mm SLE from 1950 through 2080.

Mernild, Sebastian Haugard [Los Alamos National Laboratory; Liston, Glen [COLORADO STATE UNIV.; Hiemstra, Christopher [COLORADO STATE UNIV.; Christensen, Jens [DANISH METEOROLOGICAL INS.

2009-01-01T23:59:59.000Z

260

A viscoplasticity model with an enhanced control of the yield surface distortion  

E-Print Network [OSTI]

A new model of metal viscoplasticity, which takes combined isotropic, kinematic, and distortional hardening into account, is presented. The basic modeling assumptions are illustrated using a new two-dimensional rheological analogy. This demonstrative rheological model is used as a guideline for the construction of constitutive relations. The nonlinear kinematic hardening is captured using the well-known Armstrong-Frederick approach. The distortion of the yield surface is described with the help of a so-called distortional backstress. A distinctive feature of the model is that any smooth convex saturated form of the yield surface which is symmetric with respect to the loading direction can be captured. In particular, an arbitrary sharpening of the saturated yield locus in the loading direction combined with a flattening on the opposite side can be covered. Moreover, the yield locus evolves smoothly and its convexity is guaranteed at each hardening stage. A strict proof of the thermodynamic consistency is provided. Finally, the predictive capabilities of the material model are verified using the experimental data for a very high work hardening annealed aluminum alloy 1100 Al.

A. V. Shutov; J. Ihlemann

2012-03-31T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" 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

Surface Wave Effects in the NEMO Ocean Model: Forced and Coupled Experiments  

E-Print Network [OSTI]

The NEMO general circulation ocean model is extended to incorporate three physical processes related to ocean surface waves, namely the surface stress (modified by growth and dissipation of the oceanic wave field), the turbulent kinetic energy flux from breaking waves, and the Stokes-Coriolis force. Experiments are done with NEMO in ocean-only (forced) mode and coupled to the ECMWF atmospheric and wave models. Ocean-only integrations are forced with fields from the ERA-Interim reanalysis. All three effects are noticeable in the extra-tropics, but the sea-state dependent turbulent kinetic energy flux yields by far the largest difference. This is partly because the control run has too vigorous deep mixing due to an empirical mixing term in NEMO. We investigate the relation between this ad hoc mixing and Langmuir turbulence and find that it is much more effective than the Langmuir parameterization used in NEMO. The biases in sea surface temperature as well as subsurface temperature are reduced, and the total oce...

Breivik, Øyvind; Bidlot, Jean-Raymond; Balmaseda, Magdalena Alonso; Janssen, Peter A E M

2015-01-01T23:59:59.000Z

262

Research priorities in land use and land-cover change for the Earth system and integrated assessment modelling  

E-Print Network [OSTI]

). Copyright ? 2010 Royal Meteorological Society and Crown Copyright. KEY WORDS land use; land cover; Earth system models; integrated assessment models; research priorities Received 12 January 2009; Revised 9 March 2010; Accepted 14 March 2010 1. Introduction 1... biogeophysical, socio- economic and human decision-making perspectives. The Earth System Modeling (ESM) and the Integrated Assessment Modeling (IAM) communities play an impor- tant role in understanding and quantifying Earth system analysis and, specifically...

Hibbard, Kathy; Janetos, Anthony; van Vuuren, Detlef P.; Pongtatz, Julia; Rose, Steven K.; Betts, Richard; Herold, Martin; Feddema, Johannes J.

2010-01-01T23:59:59.000Z

263

On the Use of Computational Models for Wave Climate Assessment in Support of the Wave Energy Industry  

E-Print Network [OSTI]

Effective, economic extraction of ocean wave energy requires an intimate under- standing of the ocean waveOn the Use of Computational Models for Wave Climate Assessment in Support of the Wave Energy On the Use of Computational Models for Wave Climate Assessment in Support of the Wave Energy Industry

Victoria, University of

264

MHD modelling of liquid metal films for fusion divertor surface protection  

SciTech Connect (OSTI)

In order to counter adverse effects resulting from the impingement of high energy plasmas on solid material surfaces, especially as this relates to fusion reactor high heat flux components, the idea of protecting the material surface with a thin film of liquid metal has been advanced. In principle, this film would protect the underlying substrate from physical sputtering and reduce thermal stresses in the structure. However, serious concerns related to establishing such a liquid metal flow and its performance in a fusion environment need to be addressed. In particular, the interaction of the conducting metal film with the complicated magnetic fields typical of a diverted reactor plasma may lead to retardation of the film resulting in channel flooding, velocity profiles not conducive to effective heat transfer, and possibly even detachment of the film from the substrate. In addition, the momentum carried by the plasma particles may deform the film shape to a significant extent, possibly disrupting the flow or leaving sections on the substrate inadequately protected. Proposed here are several mathematical and experimental models intended to address these specific questions. Mathematical models will be derived from the basic set of incompressible magnetohydrodynamic equations for the cases of fully developed and developing film flow. The fully developed flow model allows simplification of the governing equations to two dimensions, facilitating their solution. The data obtained from this formulation will yield the velocity, induced magnetic field, and height of the film as a function of space and flow parameters. From this data the effect of the plasma momentum on the shape of the surface will be seen, as will the velocity structure across the channel, a structure that is only assumed in previous modeling attempts. The developing film model, based on simplifying assumptions for the height and velocity profiles determined from the previous model for the fully developed case, will account for spatial and temporal varying magnetic fields. In this way it will be possible to model more fusion relevant field distributions and establish their effect on the evolution of the film and its possible flooding or detachment as it flows along the substrate.

Morley, N.B.

1991-12-31T23:59:59.000Z

265

Model Components of the Certification Framework for Geologic Carbon Sequestration Risk Assessment  

SciTech Connect (OSTI)

We have developed a framework for assessing the leakage risk of geologic carbon sequestration sites. This framework, known as the Certification Framework (CF), emphasizes wells and faults as the primary potential leakage conduits. Vulnerable resources are grouped into compartments, and impacts due to leakage are quantified by the leakage flux or concentrations that could potentially occur in compartments under various scenarios. The CF utilizes several model components to simulate leakage scenarios. One model component is a catalog of results of reservoir simulations that can be queried to estimate plume travel distances and times, rather than requiring CF users to run new reservoir simulations for each case. Other model components developed for the CF and described here include fault characterization using fault-population statistics; fault connection probability using fuzzy rules; well-flow modeling with a drift-flux model implemented in TOUGH2; and atmospheric dense-gas dispersion using a mesoscale weather prediction code.

Oldenburg, Curtis M.; Bryant, Steven L.; Nicot, Jean-Philippe; Kumar, Navanit; Zhang, Yingqi; Jordan, Preston; Pan, Lehua; Granvold, Patrick; Chow, Fotini K.

2009-06-01T23:59:59.000Z

266

Phase diagram and surface tension in the three-flavor Polyakov-quark-meson model  

E-Print Network [OSTI]

We obtain the in-medium effective potential of the three-flavor Polyakov-Quark-Meson model as a real function of real variables in the Polyakov loop variable, to allow for the study of all possible minima of the model. At finite quark chemical potential, the real and imaginary parts of the effective potential, in terms of the Polyakov loop variables, are made apparent, showing explicitly the fermion sign problem of the theory. The phase diagram and other equilibrium observables, obtained from the real part of the effective potential, are calculated in the mean-field approximation. The obtained results are compared to those found with the so-called saddle-point approach. Our procedure also allows the calculation of the surface tension between the chirally broken and confined phase, and the chirally restored and deconfined phase. The values of surface tension we find for low temperatures are very close to the ones recently found for two-flavor chiral models. Some consequences of our results for the early Universe, for heavy-ion collisions, and for proto-neutron stars are briefly discussed.

Bruno W. Mintz; Rudnei O. Ramos; Juergen Schaffner-Bielich; Rainer Stiele

2013-02-28T23:59:59.000Z

267

Analytical modeling of localized surface plasmon resonance in heterostructure copper sulfide nanocrystals  

SciTech Connect (OSTI)

Localized surface plasmon resonance (LSPR) in semiconductor nanocrystals is a relatively new field of investigation that promises greater tunability of plasmonic properties compared to metal nanoparticles. A novel process by which the LSPR in semiconductor nanocrystals can be altered is through heterostructure formation arising from solution-based cation exchange. Herein, we describe the development of an analytical model of LSPR in heterostructure copper sulfide-zinc sulfide nanocrystals synthesized via a cation exchange reaction between copper sulfide (Cu{sub 1.81}S) nanocrystals and Zn ions. The cation exchange reaction produces dual-interface, heterostructure nanocrystals in which the geometry of the copper sulfide phase can be tuned from a sphere to a thin disk separating symmetrically-grown sulfide (ZnS) grains. Drude model electronic conduction and Mie-Gans theory are applied to describe how the LSPR wavelength changes during cation exchange, taking into account the morphology evolution and changes to the local permittivity. The results of the modeling indicate that the presence of the ZnS grains has a significant effect on the out-of-plane LSPR mode. By comparing the results of the model to previous studies on solid-solid phase transformations of copper sulfide in these nanocrystals during cation exchange, we show that the carrier concentration is independent of the copper vacancy concentration dictated by its atomic phase. The evolution of the effective carrier concentration calculated from the model suggests that the out-of-plane resonance mode is dominant. The classical model was compared to a simplified quantum mechanical model which suggested that quantum mechanical effects become significant when the characteristic size is less than ?8 nm. Overall, we find that the analytical models are not accurate for these heterostructured semiconductor nanocrystals, indicating the need for new model development for this emerging field.

Caldwell, Andrew H.; Ha, Don-Hyung; Robinson, Richard D., E-mail: rdr82@cornell.edu [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853 (United States); Ding, Xiaoyue [School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853 (United States)

2014-10-28T23:59:59.000Z

268

Modelling risk and risking models: the diffusive boundary between science and policy in volcanic risk assessment  

E-Print Network [OSTI]

to the appreciation that the eruptions may continue for 282 decades and should be regarded as a “chronic” problem for planning purposes (Donovan and 283 Oppenheimer, 2014). Managing this transition has required consistent yet innovative 284 approaches to scientific... to their advice. 524 There is abundant evidence of the political challenges of risk assessment and management on 525 Montserrat, and the complex boundaries and connectivities involved (Aspinall et al., 2002; 526 Haynes et al., 2007; Donovan and Oppenheimer...

Donovan, Amy R.; Oppenheimer, Clive

2014-11-27T23:59:59.000Z

269

Modeling threat assessments of water supply systems using markov latent effects methodology.  

SciTech Connect (OSTI)

Recent amendments to the Safe Drinking Water Act emphasize efforts toward safeguarding our nation's water supplies against attack and contamination. Specifically, the Public Health Security and Bioterrorism Preparedness and Response Act of 2002 established requirements for each community water system serving more than 3300 people to conduct an assessment of the vulnerability of its system to a terrorist attack or other intentional acts. Integral to evaluating system vulnerability is the threat assessment, which is the process by which the credibility of a threat is quantified. Unfortunately, full probabilistic assessment is generally not feasible, as there is insufficient experience and/or data to quantify the associated probabilities. For this reason, an alternative approach is proposed based on Markov Latent Effects (MLE) modeling, which provides a framework for quantifying imprecise subjective metrics through possibilistic or fuzzy mathematics. Here, an MLE model for water systems is developed and demonstrated to determine threat assessments for different scenarios identified by the assailant, asset, and means. Scenario assailants include terrorists, insiders, and vandals. Assets include a water treatment plant, water storage tank, node, pipeline, well, and a pump station. Means used in attacks include contamination (onsite chemicals, biological and chemical), explosives and vandalism. Results demonstrated highest threats are vandalism events and least likely events are those performed by a terrorist.

Silva, Consuelo Juanita

2006-12-01T23:59:59.000Z

270

Water balance in the Amazon basin from a land surface model ensemble  

SciTech Connect (OSTI)

Despite recent advances in modeling and remote sensing of land surfaces, estimates of the global water budget are still fairly uncertain. The objective of this study is to evaluate the water budget of the Amazon basin based on several state-of-the-art land surface model (LSM) outputs. Water budget variables [total water storage (TWS), evapotranspiration (ET), surface runoff (R) and baseflow (B)] are evaluated at the basin scale using both remote sensing and in situ data. Fourteen LSMs were run using meteorological forcings at a 3-hourly time step and 1-degree spatial resolution. Three experiments are performed using precipitation which has been rescaled to match monthly global GPCP and GPCC datasets and the daily HYBAM dataset for the Amazon basin. R and B are used to force the Hydrological Modeling and Analysis Platform (HyMAP) river routing scheme and simulated discharges are compared against observations at 165 gauges. Simulated ET and TWS are compared against FLUXNET and MOD16A2 evapotranspiration, and GRACE TWS estimates in different catchments. At the basin scale, simulated ET ranges from 2.39mm.d-1 to 3.26mm.d-1 and a low spatial correlation between ET and P indicates that evapotranspiration does not depend on water availability over most of the basin. Results also show that other simulated water budget variables vary significantly as a function of both the LSM and precipitation used, but simulated TWS generally agree at the basin scale. The best water budget simulations resulted from experiments using the HYBAM dataset, mostly explained by a denser rainfall gauge network the daily rescaling.

Getirana, Augusto; Dutra, Emanuel; Guimberteau, Matthieu; Kam, Jonghun; Li, Hongyi; Decharme, Bertrand; Zhang, Zhengqiu J.; Ducharne, Agnes; Boone, Aaron; Balsamo, Gianpaolo; Rodell, Matthew; Mounirou Toure, Ally; Xue, Yongkang; Peters-Lidard, Christa D.; Kumar, Sujay V.; Arsenault, Kristi Rae; Drapeau, Guillaume; Leung, Lai-Yung R.; Ronchail, Josyane; Sheffield, Justin

2014-12-06T23:59:59.000Z

271

Towards a tool to design vegetated strips for mitigation of pesticides transfers in surface runoff. Assessment of different  

E-Print Network [OSTI]

(Simunek et al,1999) coupled with a kinematic wave equation, which represents both surface runoff pollutions. Water pollution control division. Cemagref. 3 Bis Quai Chauveau. 69 336 LYON 09. France. * nadia fields towards surface waters. However, as the efficiency of these structures is closely related

Paris-Sud XI, Université de

272

Performance Assessment Modeling and Sensitivity Analyses of Generic Disposal System Concepts.  

SciTech Connect (OSTI)

directly, rather than through simplified abstractions. It also a llows for complex representations of the source term, e.g., the explicit representation of many individual waste packages (i.e., meter - scale detail of an entire waste emplacement drift). This report fulfills the Generic Disposal System Analysis Work Packa ge Level 3 Milestone - Performance Assessment Modeling and Sensitivity Analyses of Generic Disposal System Concepts (M 3 FT - 1 4 SN08080 3 2 ).

Sevougian, S. David; Freeze, Geoffrey A. [Sandia National Laboratories, Albuquerque, NM; Gardner, William Payton [Sandia National Laboratories, Albuquerque, NM; Hammond, Glenn Edward [Sandia National Laboratories, Albuquerque, NM; Mariner, Paul [Sandia National Laboratories, Albuquerque, NM

2014-09-01T23:59:59.000Z

273

Global estimation of evapotranspiration using a leaf area index-based surface energy and water balance model  

E-Print Network [OSTI]

using Advanced Very High Res- olution Radiometer Lai data, Climate Research Unit climate dataGlobal estimation of evapotranspiration using a leaf area index-based surface energy and water-relative-humidity-based two-source (ARTS) E model that simulates the surface energy balance, soil water balance

Martin, Timothy

274

Discrepancies in the prediction of solar wind using potential field source surface model: An investigation of possible sources  

E-Print Network [OSTI]

Discrepancies in the prediction of solar wind using potential field source surface model expansion factor (FTE) at the source surface and the solar wind speed (SWS) observed at Earth, which has been made use of in the prediction of solar wind speed near the Earth with reasonable accuracy. However

California at Berkeley, University of

275

Assimilation of surface data in a one-dimensional physical-biogeochemical model of the surface ocean: 1. Method and preliminary results  

SciTech Connect (OSTI)

This paper describes a method to estimate parameters of complex ocean carbon cycle models and to estimate carbon fluxes other than primary production from satellite data. A one-dimensional vertical model, which couples the physics of the ocean mixed layer and biogeochemical processes, was used to simulate the carbon cycle. Variational assimilation was applied to globally adjust the model solution. Consistent results were found for the grazing rate, the phytoplankton mortality rate, and the minimum concentration of zooplankton in winter. Some carbon fluxes appeared to be robustly constrained; however, primary production is apparently underestimated. The study results suggest that a simplified biological model would adequately the seasonal evolution of surface chlorophyll concentration, and would be more adapted to transform satellite data into carbon fluxes. Analysis of model behavior during assimilation experiments also provided information for other possible simplifications of the trophic model. 49 refs., 17 figs., 5 tabs.

Prunet, P.; Minster, J.F. [Laboratoire CNES-CNRS, Toulouse (France)] [Laboratoire CNES-CNRS, Toulouse (France); Ruiz-Pino, D. [Universite Pierre et Marie Curie, Paris (France)] [Universite Pierre et Marie Curie, Paris (France)

1996-03-01T23:59:59.000Z

276

Impact of Hillslope-Scale Organization of Topography, Soil Moisture, Soil Temperature, and Vegetation on Modeling Surface Microwave Radiation Emission  

E-Print Network [OSTI]

Microwave radiometry will emerge as an important tool for global remote sensing of near-surface soil moisture in the coming decade. In this modeling study, we find that hillslope-scale topography (tens of meters) influences ...

Flores, Alejandro N.

277

Development of Simplified Probabilistic Risk Assessment Model for Seismic Initiating Event  

SciTech Connect (OSTI)

ABSTRACT This paper discusses a simplified method to evaluate seismic risk using a methodology built on dividing the seismic intensity spectrum into multiple discrete bins. The seismic probabilistic risk assessment model uses Nuclear Regulatory Commission’s (NRC’s) full power Standardized Plant Analysis Risk (SPAR) model as the starting point for development. The seismic PRA models are integrated with their respective internal events at-power SPAR model. This is accomplished by combining the modified system fault trees from the full power SPAR model with seismic event tree logic. The peak ground acceleration is divided into five bins. The g-value for each bin is estimated using the geometric mean of lower and upper values of that particular bin and the associated frequency for each bin is estimated by taking the difference between upper and lower values of that bin. The component’s fragilities are calculated for each bin using the plant data, if available, or generic values of median peak ground acceleration and uncertainty values for the components. For human reliability analysis (HRA), the SPAR HRA (SPAR-H) method is used which requires the analysts to complete relatively straight forward worksheets that include the performance shaping factors (PSFs). The results are then used to estimate human error probabilities (HEPs) of interest. This work is expected to improve the NRC’s ability to include seismic hazards in risk assessments for operational events in support of the reactor oversight program (e.g., significance determination process).

S. Khericha; R. Buell; S. Sancaktar; M. Gonzalez; F. Ferrante

2012-06-01T23:59:59.000Z

278

Model assessment of protective barriers: Part 3. Status of FY 1990 work  

SciTech Connect (OSTI)

Radioactive waste exists at the US Department of Energy`s (DOE`s) Hanford Site in a variety of locations, including subsurface grout and tank farms, solid waste burial grounds, and contaminated soil sites. Some of these waste sites may need to be isolated from percolating water to minimize the potential for transport of the waste to the ground water, which eventually discharges to the Columbia River. Multilayer protective barriers have been proposed as a means of limiting the flow of water through the waste sites (DOE 1987). A multiyear research program [managed jointly by Pacific Northwest Laboratory (PNL) and Westinghouse Hanford Company for the DOE] is aimed at assessing the performance of these barriers. One aspect of this program involves the use of computer models to predict barrier performance. Three modeling studies have already been conducted and a test plan was produced. The simulation work reported here was conducted by PNL and extends the previous modeling work. The purpose of this report are to understand phenomena that have been observed in the field and to provide information that can be used to improve hydrologic modeling of the protective barrier. An improved modeling capability results in better estimates of barrier performance. Better estimates can be used to improve the design of barriers and the assessment of their long-term performance.

Fayer, M.J.; Rockhold, M.L.; Holford, D.J.

1992-02-01T23:59:59.000Z

279

Modeling Electrochemical Decomposition of Fluoroethylene Carbonate on Silicon Anode Surfaces in Lithium Ion Batteries  

E-Print Network [OSTI]

Fluoroethylene carbonate (FEC) shows promise as an electrolyte additive for improving passivating solid-electrolyte interphase (SEI) films on silicon anodes used in lithium ion batteries (LIB). We apply density functional theory (DFT), ab initio molecular dynamics (AIMD), and quantum chemistry techniques to examine excess-electron-induced FEC molecular decomposition mechanisms that lead to FEC-modified SEI. We consider one- and two-electron reactions using cluster models and explicit interfaces between liquid electrolyte and model Li(x)Si(y) surfaces, respectively. FEC is found to exhibit more varied reaction pathways than unsubstituted ethylene carbonate. The initial bond-breaking events and products of one- and two-electron reactions are qualitatively similar, with a fluoride ion detached in both cases. However, most one-electron products are charge-neutral, not anionic, and may not coalesce to form effective Li+-conducting SEI unless they are further reduced or take part in other reactions. The implication...

Leung, Kevin; Foster, Michael E; Ma, Yuguang; del la Hoz, Julibeth M Martinez; Sai, Na; Balbuena, Perla B

2014-01-01T23:59:59.000Z

280

Production of excitons in grazing collisions of protons with LiF surfaces: An onion model  

SciTech Connect (OSTI)

In this work we evaluate the production of excitons of a lithium fluoride crystal induced by proton impact in the intermediate and high energy regime (from 100 keV to 1 MeV). A simple model is proposed to account for the influence of the Coulomb grid of the target by dressing crystal ions to transform them in what we call onions. The excited states of these onions can be interpreted as excitons. Within this model, total cross section and stopping power are calculated by using the first Born and the continuum distorted-wave (CDW) eikonal initial-state (EIS) approximations. We found that between 7 and 30 excitons per incident proton are produced in grazing collisions with LiF surfaces, becoming a relevant mechanism of inelastic transitions.

Miraglia, J. E.; Gravielle, M. S. [Instituto de Astronomia y Fisica del Espacio, Consejo Nacional de Investigaciones Cientificas y Tecnicas and Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Casilla de Correo 67, Sucursal 28, (C1428EGA) Buenos Aires (Argentina)

2011-12-15T23:59:59.000Z

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281

CHEMICAL MODELING OF INFRARED DARK CLOUDS: THE ROLE OF SURFACE CHEMISTRY  

SciTech Connect (OSTI)

We simulate the chemistry of infrared dark clouds (IRDCs) with a model in which the physical conditions are homogeneous and time independent. The chemistry is solved as a function of time with three networks: one purely gas phase, one that includes accretion and desorption, and one, the complete gas-grain network, that includes surface chemistry in addition. We compare our results with observed molecular abundances for two representative IRDCs-IRDC013.90-1 and IRDC321.73-1-using the molecular species N{sub 2}H{sup +}, HC{sub 3}N, HNC, HCO{sup +}, HCN, C{sub 2}H, NH{sub 3}, and CS. IRDC013.90-1 is a cold IRDC, with a temperature below 20 K, while IRDC321.73-1 is somewhat warmer, in the range 20-30 K. We find that the complete gas-grain model fits the data very well, but that the goodness of fit is not sharply peaked at a particular temperature. Surface processes are important for the explanation of the high gas-phase abundance of N{sub 2}H{sup +} in IRDC321.73-1. The general success of the zero-dimensional model in reproducing single-dish observations of our limited sample of eight species shows that it is probably sufficient for an explanation of this type of data. To build and justify more complicated models, including spatial temperature and density structure, contraction, and heating, we require high-resolution interferometric data.

Vasyunina, T.; Vasyunin, A. I.; Herbst, Eric [Department of Chemistry, University of Virginia, Charlottesville, VA 22904 (United States); Linz, H. [Max Planck Institute for Astronomy (MPIA), Koenigstuhl 17, D-69117 Heidelberg (Germany)

2012-06-01T23:59:59.000Z

282

Assessment of clear and cloudy sky parameterizations for daily downwelling longwave radiation over different land surfaces in  

E-Print Network [OSTI]

meteorological data, resulting in reliable quantification of net radiation and evapotranspiration in FloridaAssessment of clear and cloudy sky parameterizations for daily downwelling longwave radiation over sky downwelling longwave radiation (Rldc) and cloudy sky downwelling longwave radiation (Rld) formulas

283

Modeling of Near-Surface Leakage and Seepage of CO2 for Risk Characterization  

SciTech Connect (OSTI)

The injection of carbon dioxide (CO2) into deep geologic carbon sequestration sites entails risk that CO2 will leak away from the primary storage formation and migrate upwards to the unsaturated zone from which it can seep out of the ground. We have developed a coupled modeling framework called T2CA for simulating CO2 leakage and seepage in the subsurface and in the atmospheric surface layer. The results of model simulations can be used to calculate the two key health, safety, and environmental (HSE) risk drivers, namely CO2 seepage flux and nearsurface CO2 concentrations. Sensitivity studies for a subsurface system with a thick unsaturated zone show limited leakage attenuation resulting in correspondingly large CO2 concentrations in the shallow subsurface. Large CO2 concentrations in the shallow subsurface present a risk to plant and tree roots, and to humans and other animals in subsurface structures such as basements or utility vaults. Whereas CO2 concentrations in the subsurface can be high, surfacelayer winds reduce CO2 concentrations to low levels for the fluxes investigated. We recommend more verification and case studies be carried out with T2CA, along with the development of extensions to handle additional scenarios such as calm conditions, topographic effects, and catastrophic surface-layer discharge events.

Oldenburg, Curtis M.; Unger, Andre A.J.

2004-02-18T23:59:59.000Z

284

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

SciTech Connect (OSTI)

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

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

2004-07-01T23:59:59.000Z

285

An Integrated Model for Assessment of Sustainable Agricultural Residue Removal Limits for Bioenergy Systems  

SciTech Connect (OSTI)

Agricultural residues have been identified as a significant potential resource for bioenergy production, but serious questions remain about the sustainability of harvesting residues. Agricultural residues play an important role in limiting soil erosion from wind and water and in maintaining soil organic carbon. Because of this, multiple factors must be considered when assessing sustainable residue harvest limits. Validated and accepted modeling tools for assessing these impacts include the Revised Universal Soil Loss Equation Version 2 (RUSLE2), the Wind Erosion Prediction System (WEPS), and the Soil Conditioning Index. Currently, these models do not work together as a single integrated model. Rather, use of these models requires manual interaction and data transfer. As a result, it is currently not feasible to use these computational tools to perform detailed sustainable agricultural residue availability assessments across large spatial domains or to consider a broad range of land management practices. This paper presents an integrated modeling strategy that couples existing datasets with the RUSLE2 water erosion, WEPS wind erosion, and Soil Conditioning Index soil carbon modeling tools to create a single integrated residue removal modeling system. This enables the exploration of the detailed sustainable residue harvest scenarios needed to establish sustainable residue availability. Using this computational tool, an assessment study of residue availability for the state of Iowa was performed. This study included all soil types in the state of Iowa, four representative crop rotation schemes, variable crop yields, three tillage management methods, and five residue removal methods. The key conclusions of this study are that under current management practices and crop yields nearly 26.5 million Mg of agricultural residue are sustainably accessible in the state of Iowa, and that through the adoption of no till practices residue removal could sustainably approach 40 million Mg. However, when considering the economics and logistics of residue harvest, yields below 2.25 Mg ha-1 are generally considered to not be viable for a commercial bioenergy system. Applying this constraint, the total agricultural residue resource available in Iowa under current management practices is 19 million Mg. Previously published results have shown residue availability from 22 million Mg to over 50 million Mg in Iowa.

D. Muth; K. M. Bryden

2003-12-01T23:59:59.000Z

286

Waste package performance assessment: Deterministic system model, program scope and specification  

SciTech Connect (OSTI)

Integrated assessments of the performance of nuclear waste package designs must be made in order to qualify waste package designs with respect to containment time and release-rate requirements. PANDORA is a computer-based model of the waste package and of the processes affecting it over the long terms, specific to conditions at the proposed Yucca Mountain, Nevada, site. The processes PANDORA models include: changes in inventories due to radioactive decay, gamma radiation dose rate in and near the package, heat transfer, mechanical behavior, groundwater contact, corrosion, waste form alteration, and radionuclide release. The model tracks the development and coupling of these processes over time. The process models are simplified ones that focus on major effects and on coupling. This report documents our conceptual model development and provides a specification for the computer program. The current model is the first in a series. Succeeding models will use guidance from results of preceding models in the PANDORA series and will incorporate results of recently completed experiments and calculations on processes affecting performance. 22 refs., 21 figs., 9 tabs.

O`Connell, W.J.; Drach, R.S.

1986-10-02T23:59:59.000Z

287

Soil-to-Plant Concentration Ratios for Assessing Food Chain Pathways in Biosphere Models  

SciTech Connect (OSTI)

This report describes work performed for the U.S. Nuclear Regulatory Commission’s project Assessment of Food Chain Pathway Parameters in Biosphere Models, which was established to assess and evaluate a number of key parameters used in the food-chain models used in performance assessments of radioactive waste disposal facilities. Section 2 of this report summarizes characteristics of samples of soils and groundwater from three geographical regions of the United States, the Southeast, Northwest, and Southwest, and analyses performed to characterize their physical and chemical properties. Because the uptake and behavior of radionuclides in plant roots, plant leaves, and animal products depends on the chemistry of the water and soil coming in contact with plants and animals, water and soil samples collected from these regions of the United States were used in experiments at Pacific Northwest National Laboratory to determine radionuclide soil-to-plant concentration ratios. Crops and forage used in the experiments were grown in the soils, and long-lived radionuclides introduced into the groundwater provide the contaminated water used to water the grown plants. The radionuclides evaluated include 99Tc, 238Pu, and 241Am. Plant varieties include alfalfa, corn, onion, and potato. The radionuclide uptake results from this research study show how regional variations in water quality and soil chemistry affect radionuclide uptake. Section 3 summarizes the procedures and results of the uptake experiments, and relates the soil-to-plant uptake factors derived. In Section 4, the results found in this study are compared with similar values found in the biosphere modeling literature; the study’s results are generally in line with current literature, but soil- and plant-specific differences are noticeable. This food-chain pathway data may be used by the NRC staff to assess dose to persons in the reference biosphere (e.g., persons who live and work in an area potentially affected by radionuclide releases) of waste disposal facilities and decommissioning sites.

Napier, Bruce A.; Fellows, Robert J.; Krupka, Kenneth M.

2007-10-01T23:59:59.000Z

288

Hydrophobic force field as molecular alternative to surface-area models  

SciTech Connect (OSTI)

An effective force field for hydrophobic interactions is developed based on a modified potential-of-mean-force (PMF) expansion of the effective many-body interactions between nonpolar molecules in water. For the simplest nonpolar solutes in water, hard particles, the modified PMF expansion is exact in both limiting cases of infinite separation and perfect overlap. The hydrophobic interactions are parametrized by using the information-theory model of hydrophobic hydration. The interactions between nonpolar solutes are short-ranged and can be evaluated efficiently on a computer. The force field is compared with simulation data for alkane conformational equilibria in water as well as a model for the formation of a hydrophobic core of a protein. The modified PMF expansion can be extended to solutes with attractive interactions. The observed accuracy, computational efficiency, and atomic detail of the model suggest that this simple hydrophobic force field can lead to a molecular alternative for phenomenological surface-area models with applications in ligand-binding and protein-folding studies.

Hummer, G.

1999-07-07T23:59:59.000Z

289

Assessment of Food Chain Pathway Parameters in Biosphere Models: Annual Progress Report for Fiscal Year 2004  

SciTech Connect (OSTI)

This Annual Progress Report describes the work performed and summarizes some of the key observations to date on the U.S. Nuclear Regulatory Commission’s project Assessment of Food Chain Pathway Parameters in Biosphere Models, which was established to assess and evaluate a number of key parameters used in the food-chain models used in performance assessments of radioactive waste disposal facilities. Section 2 of this report describes activities undertaken to collect samples of soils from three regions of the United States, the Southeast, Northwest, and Southwest, and perform analyses to characterize their physical and chemical properties. Section 3 summarizes information gathered regarding agricultural practices and common and unusual crops grown in each of these three areas. Section 4 describes progress in studying radionuclide uptake in several representative crops from the three soil types in controlled laboratory conditions. Section 5 describes a range of international coordination activities undertaken by Project staff in order to support the underlying data needs of the Project. Section 6 provides a very brief summary of the status of the GENII Version 2 computer program, which is a “client” of the types of data being generated by the Project, and for which the Project will be providing training to the US NRC staff in the coming Fiscal Year. Several appendices provide additional supporting information.

Napier, Bruce A.; Krupka, Kenneth M.; Fellows, Robert J.; Cataldo, Dominic A.; Valenta, Michelle M.; Gilmore, Tyler J.

2004-12-02T23:59:59.000Z

290

On the Sensitivity of Atmospheric Model Implied Ocean Heat Transport to the Dominant Terms of the Surface Energy Balance  

SciTech Connect (OSTI)

The oceanic meridional heat transport (T{sub o}) implied by an atmospheric General Circulation Model (GCM) can help evaluate a model's readiness for coupling with an ocean GCM. In this study we examine the T{sub o} from benchmark experiments of the Atmospheric Model Intercomparison Project, and evaluate the sensitivity of T{sub o} to the dominant terms of the surface energy balance. The implied global ocean TO in the Southern Hemisphere of many models is equatorward, contrary to most observationally-based estimates. By constructing a hybrid (model corrected by observations) T{sub o}, an earlier study demonstrated that the implied heat transport is critically sensitive to the simulated shortwave cloud radiative effects, which have been argued to be principally responsible for the Southern Hemisphere problem. Systematic evaluation of one model in a later study suggested that the implied T{sub o} could be equally as sensitive to a model's ocean surface latent heat flux. In this study we revisit the problem with more recent simulations, making use of estimates of ocean surface fluxes to construct two additional hybrid calculations. The results of the present study demonstrate that indeed the implied T{sub o} of an atmospheric model is very sensitive to problems in not only the surface net shortwave, but the latent heat flux as well. Many models underestimate the shortwave radiation reaching the surface in the low latitudes, and overestimate the latent heat flux in the same region. The additional hybrid transport calculations introduced here could become useful model diagnostic tests as estimates of implied ocean surface fluxes are improved.

Gleckler, P J

2004-11-03T23:59:59.000Z

291

Modeling gas and brine migration for assessing compliance of the Waste Isolation Pilot Plant  

SciTech Connect (OSTI)

At the request of the WIPP Project Integration Office (WPIO) of the DOE, the WIPP Performance Assessment (PA) Department of Sandia National Laboratories (SNL) has completed preliminary uncertainty and sensitivity analyses of gas and brine migration away from the undisturbed repository. This paper contains descriptions of the numerical model and simulations, including model geometries and parameter values, and a summary of major conclusions from sensitivity analyses. Because significant transport of contaminants can only occur in a fluid (gas or brine) medium, two-phase flow modeling can provide an estimate of the distance to which contaminants can migrate. Migration of gas or brine beyond the RCRA ``disposal-unit boundary`` or the Standard`s accessible environment constitutes a potential, but not certain, violation and may require additional evaluations of contaminant concentrations.

Vaughn, P. [Applied Physics, Inc., Albuquerque, NM (United States); Butcher, B. [Sandia National Labs., Albuquerque, NM (United States); Helton, J. [Arizona State Univ., Tempe, AZ (United States); Swift, P. [Tech. Reps., Inc., Albuquerque, NM (United States)

1993-10-01T23:59:59.000Z

292

Molecular adsorption of alkanes on platinum surfaces: A predictive theoretical model  

SciTech Connect (OSTI)

The adsorption probabilities of methane and propane on Pt(111), and propane on Pt(110)-(1{times}2) have been successfully predicted for a wide range of incident energies and angles with classical stochastic trajectory simulations, using a pairwise additive Morse methyl{endash}platinum potential previously developed from the measured trapping probabilities of ethane on Pt(111). These predictions, along with those for ethane adsorption on Pt(110){endash}(1{times}2), comprise a unified model for the molecular adsorption of alkanes on platinum surfaces. The simulations show the initial trapping probabilities of methane and propane on Pt(111) are determined to within approximately 10{percent} by the fate of the first bounce. They also indicate that at normal incidence on Pt(111) energy conversions from perpendicular translational motion to both cartwheeling rotation and lattice phonons play increasingly important roles in increasing the trapping probability as the alkane increases in size and molecular weight. For methane itself excitation of parallel translational momentum after the first bounce serves as the most effective energy storage mechanism which facilitates trapping, whereas for propane cartwheel rotational motion plays the dominant role. Excessive excitation of these modes of motion, however, can cause scattering on subsequent bounces by reconversion of the energy into perpendicular translational energy. Collisions of methane with the hollow and bridge sites on the Pt(111) surface appear less effective in trapping than do atop sites. The simulations also suggest excitation of the C{endash}C{endash}C bending mode of propane has little effect on the trapping of propane on platinum surfaces for beam energies below 55 kJ/mol. {copyright} {ital 1996 American Institute of Physics.}

Stinnett, J.A.; Madix, R.J. [Department of Chemical Engineering, Stanford University, Stanford, California 94305 (United States)] [Department of Chemical Engineering, Stanford University, Stanford, California 94305 (United States)

1996-07-01T23:59:59.000Z

293

Optimization of the GB/SA Solvation Model for Predicting the Structure of Surface Loops in Proteins  

E-Print Network [OSTI]

Optimization of the GB/SA Solvation Model for Predicting the Structure of Surface Loops in ProteinsVed: October 10, 2005; In Final Form: December 1, 2005 Implicit solvation models are commonly optimized the force field is sometimes not considered. In previous studies, we have developed an optimization

Meirovitch, Hagai

294

Modeling and Quantification of Team Performance in Human Reliability Analysis for Probabilistic Risk Assessment  

SciTech Connect (OSTI)

Probabilistic Risk Assessment (PRA) and Human Reliability Assessment (HRA) are important technical contributors to the United States (U.S.) Nuclear Regulatory Commission’s (NRC) risk-informed and performance based approach to regulating U.S. commercial nuclear activities. Furthermore, all currently operating commercial NPPs in the U.S. are required by federal regulation to be staffed with crews of operators. Yet, aspects of team performance are underspecified in most HRA methods that are widely used in the nuclear industry. There are a variety of "emergent" team cognition and teamwork errors (e.g., communication errors) that are 1) distinct from individual human errors, and 2) important to understand from a PRA perspective. The lack of robust models or quantification of team performance is an issue that affects the accuracy and validity of HRA methods and models, leading to significant uncertainty in estimating HEPs. This paper describes research that has the objective to model and quantify team dynamics and teamwork within NPP control room crews for risk informed applications, thereby improving the technical basis of HRA, which improves the risk-informed approach the NRC uses to regulate the U.S. commercial nuclear industry.

Jeffrey C. JOe; Ronald L. Boring

2014-06-01T23:59:59.000Z

295

A Home Ignition Assessment Model Applied to Structures in the Wildland-Urban Interface  

SciTech Connect (OSTI)

The issue of exterior fire threat to buildings, from either wildfires in the wildland-urban interface or neighboring structure fires, is critically important. To address this, theWildfire Ignition Resistant Home Design (WIRHD) program was initiated. The WIRHD program developed a tool, theWildFIREWizard, that will allow homeowners to estimate the external fire threat to their homes based on specific features and characteristics of the homes and yards. The software then makes recommendations to reduce the threat. The inputs include the structural and material features of the home and information about any ignition sources or flammable objects in its immediate vicinity, known as the home ignition zone. The tool comprises an ignition assessment model that performs explicit calculations of the radiant and convective heating of the building envelope from the potential ignition sources. This article describes a series of material ignition and flammability tests that were performed to calibrate and/or validate the ignition assessment model. The tests involved exposing test walls with different external siding types to radiant heating and/or direct flame contact.The responses of the test walls were used to determine the conditions leading to melting, ignition, or any other mode of failure of the walls. Temperature data were used to verify the model predictions of temperature rises and ignition times of the test walls.

Biswas, Kaushik [ORNL; Werth, David [Savannah River National Laboratory, Aiken, SC; Gupta, Narendra [Savannah River National Laboratory, Aiken, SC

2013-01-01T23:59:59.000Z

296

Multi-State Physics Models of Aging Passive Components in Probabilistic Risk Assessment  

SciTech Connect (OSTI)

Multi-state Markov modeling has proved to be a promising approach to estimating the reliability of passive components - particularly metallic pipe components - in the context of probabilistic risk assessment (PRA). These models consider the progressive degradation of a component through a series of observable discrete states, such as detectable flaw, leak and rupture. Service data then generally provides the basis for estimating the state transition rates. Research in materials science is producing a growing understanding of the physical phenomena that govern the aging degradation of passive pipe components. As a result, there is an emerging opportunity to incorporate these insights into PRA. This paper describes research conducted under the Risk-Informed Safety Margin Characterization Pathway of the Department of Energy’s Light Water Reactor Sustainability Program. A state transition model is described that addresses aging behavior associated with stress corrosion cracking in ASME Class 1 dissimilar metal welds – a component type relevant to LOCA analysis. The state transition rate estimates are based on physics models of weld degradation rather than service data. The resultant model is found to be non-Markov in that the transition rates are time-inhomogeneous and stochastic. Numerical solutions to the model provide insight into the effect of aging on component reliability.

Unwin, Stephen D.; Lowry, Peter P.; Layton, Robert F.; Heasler, Patrick G.; Toloczko, Mychailo B.

2011-03-13T23:59:59.000Z

297

Economic analysis and assessment of syngas production using a modeling approach  

SciTech Connect (OSTI)

Economic analysis and modeling are essential and important issues for the development of current feedstock and process technology for bio-gasification. The objective of this study was to develop an economic model and apply to predict the unit cost of syngas production from a micro-scale bio-gasification facility. An economic model was programmed in C++ computer programming language and developed using a parametric cost approach, which included processes to calculate the total capital costs and the total operating costs. The model used measured economic data from the bio-gasification facility at Mississippi State University. The modeling results showed that the unit cost of syngas production was $1.217 for a 60 Nm-3 h-1 capacity bio-gasifier. The operating cost was the major part of the total production cost. The equipment purchase cost and the labor cost were the largest part of the total capital cost and the total operating cost, respectively. Sensitivity analysis indicated that labor costs rank the top as followed by equipment cost, loan life, feedstock cost, interest rate, utility cost, and waste treatment cost. The unit cost of syngas production increased with the increase of all parameters with exception of loan life. The annual cost regarding equipment, labor, feedstock, waste treatment, and utility cost showed a linear relationship with percent changes, while loan life and annual interest rate showed a non-linear relationship. This study provides the useful information for economic analysis and assessment of the syngas production using a modeling approach.

Kim, Hakkwan; Parajuli, Prem B.; Yu, Fei; Columbus, Eugene P.

2011-08-10T23:59:59.000Z

298

First-Principles Assessment of H[subscript 2]S and H[subscript 2]O Reaction Mechanisms and the Subsequent Hydrogen Absorption on the CeO[subscript 2](111) Surface  

E-Print Network [OSTI]

The main goal of this study is to assess the resistance of ceria against hydrogen penetration into its bulk, in the context of its application as a protective surface coating against hydrogen embrittlement in metals. We ...

Marrocchelli, Dario

299

Result Summary for the Area 5 Radioactive Waste Management Site Performance Assessment Model Version 4.113  

SciTech Connect (OSTI)

Preliminary results for Version 4.113 of the Nevada National Security Site Area 5 Radioactive Waste Management Site performance assessment model are summarized. Version 4.113 includes the Fiscal Year 2011 inventory estimate.

Shott, G. J.

2012-04-15T23:59:59.000Z

300

On the applicability of the Heliosat-2 method to assess surface solar irradiance in the Intertropical Convergence Zone,  

E-Print Network [OSTI]

on the Earth's surface and its geographical distribution is of prime importance for numerous solar-3027" DOI : 10.1080/01431161.2012.756598 #12;2 energy systems for heating and electrical power generation satisfactory for Europe, including Madeira Island (Aculinin 2008; Blanc et al. 2011; Lefèvre et al. 2007

Paris-Sud XI, Université de

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301

Decision Making Under Conditions of Uncertainty: Experimental Assessment of Decision Models  

E-Print Network [OSTI]

Letitia T. Alston, Ph.D. ? Institute for Science, Technology and Public Policy, Bush School C O L L A B O R AT O R S Steven B. Redd, Ph.D. ? Department of Political Science, University of Wisconsin-Milwaukee Mark K. Davis, Ph.D. ? National Defense..., Alex Mintz, Steven B. Redd, Xinsheng Liu, and Letitia T. Alston. Decision Making Under Conditions of Uncertainty: Experimental Assessment of Decision Models. (March 2005). A report to the National Defense University by the Institute for Science...

Vedlitz, Arnold; Mintz, Alex; Redd, Steven B.; Liu, Xinsheng; Alston, Letitia T.

2013-12-19T23:59:59.000Z

302

Modeling and Risk Assessment of CO{sub 2} Sequestration at the Geologic-basin Scale  

SciTech Connect (OSTI)

Objectives. The overall objective of this proposal was to develop tools for better understanding, modeling and risk assessment of CO{sub 2} permanence in geologic formations at the geologic basin scale. The main motivation was that carbon capture and storage (CCS) will play an important role as a climate change mitigation technology only if it is deployed at scale of gigatonne per year injections over a period of decades. Continuous injection of this magnitude must be understood at the scale of a geologic basin. Specifically, the technical objectives of this project were: (1) to develop mathematical models of capacity and injectivity at the basin scale; (2) to apply quantitative risk assessment methodologies that will inform on CO{sub 2} permanence; (3) to apply the models to geologic basins across the continental United States. These technical objectives go hand-in-hand with the overarching goals of: (1) advancing the science for deployment of CCS at scale; and (2) contributing to training the next generation of scientists and engineers that will implement and deploy CCS in the United States and elsewhere. Methods. The differentiating factor of this proposal was to perform fundamental research on migration and fate of CO{sub 2} and displaced brine at the geologic basin scale. We developed analytical sharp-interface models of the evolution of CO{sub 2} plumes over the duration of injection (decades) and after injection (centuries). We applied the analytical solutions of CO{sub 2} plume migration and pressure evolution to specific geologic basins, to estimate the maximum footprint of the plume, and the maximum injection rate that can be sustained during a certain injection period without fracturing the caprock. These results have led to more accurate capacity estimates, based on fluid flow dynamics, rather than ad hoc assumptions of an overall “efficiency factor.” We also applied risk assessment methodologies to evaluate the uncertainty in our predictions of storage capacity and leakage rates. This was possible because the analytical mathematical models provide ultrafast forward simulation and they contain few parameters. Impact. The project has been enormously successful both in terms of its scientific output (journal publications) as well as impact in the government and industry. The mathematical models and uncertainty quantification methodologies developed here o?er a physically-based approach for estimating capacity and leakage risk at the basin scale. Our approach may also facilitate deployment of CCS by providing the basis for a simpler and more coherent regulatory structure than an “individual-point-of-injection” permitting approach. It may also lead to better science-based policy for post-closure design and transfer of responsibility to the State.

Juanes, Ruben

2013-08-31T23:59:59.000Z

303

Uncertainty analysis of an aviation climate model and an aircraft price model for assessment of environmental effects  

E-Print Network [OSTI]

Estimating, presenting, and assessing uncertainties are important parts in assessment of a complex system. This thesis focuses on the assessment of uncertainty in the price module and the climate module in the Aviation ...

Jun, Mina

2007-01-01T23:59:59.000Z

304

Immunocompetent syngeneic cotton rat tumor models for the assessment of replication-competent oncolytic adenovirus  

SciTech Connect (OSTI)

Oncolytic adenoviruses as a treatment for cancer have demonstrated limited clinical activity. Contributing to this may be the relevance of preclinical animal models used to study these agents. Syngeneic mouse tumor models are generally non-permissive for adenoviral replication, whereas human tumor xenograft models exhibit attenuated immune responses to the vector. The cotton rat (Sigmodon hispidus) is susceptible to human adenovirus infection, permissive for viral replication and exhibits similar inflammatory pathology to humans with adenovirus replicating in the lungs, respiratory passages and cornea. We evaluated three transplantable tumorigenic cotton rat cell lines, CCRT, LCRT and VCRT as models for the study of oncolytic adenoviruses. All three cells lines were readily infected with adenovirus type-5-based vectors and exhibited high levels of transgene expression. The cell lines supported viral replication demonstrated by the induction of cytopathogenic effect (CPE) in tissue culture, increase in virus particle numbers and assembly of virions seen on transmission electron microscopy. In vivo, LCRT and VCRT tumors demonstrated delayed growth after injection with replicating adenovirus. No in vivo antitumor activity was seen in CCRT tumors despite in vitro oncolysis. Adenovirus was also rapidly cleared from the CCRT tumors compared to LCRT and VCRT tumors. The effect observed with the different cotton rat tumor cell lines mimics the variable results of human clinical trials highlighting the potential relevance of this model for assessing the activity and toxicity of oncolytic adenoviruses.

Steel, Jason C.; Morrison, Brian J.; Mannan, Poonam [Cancer Gene Therapy Section, Metabolism Branch, Center for Cancer Research, National Cancer Institute, Mark O. Hatfield Clinical Research Center, Room 4-5330, 10 Center Drive, Bethesda, MD 20892-1457, National Institutes of Health, Maryland (United States); Abu-Asab, Mones S. [Ultrastructural Pathology, Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Maryland (United States); Wildner, Oliver [Department of Molecular and Medical Virology, Ruhr University Bochum (Germany); Miles, Brian K.; Yim, Kevin C. [Virion Systems, Inc., Rockville, Maryland (United States); Ramanan, Vijay [Cancer Gene Therapy Section, Metabolism Branch, Center for Cancer Research, National Cancer Institute, Mark O. Hatfield Clinical Research Center, Room 4-5330, 10 Center Drive, Bethesda, MD 20892-1457, National Institutes of Health, Maryland (United States); Prince, Gregory A. [Virion Systems, Inc., Rockville, Maryland (United States); Morris, John C. [Cancer Gene Therapy Section, Metabolism Branch, Center for Cancer Research, National Cancer Institute, Mark O. Hatfield Clinical Research Center, Room 4-5330, 10 Center Drive, Bethesda, MD 20892-1457, National Institutes of Health, Maryland (United States)], E-mail: jmorris@mail.nih.gov

2007-12-05T23:59:59.000Z

305

Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992. Volume 3, Model parameters: Sandia WIPP Project  

SciTech Connect (OSTI)

This volume documents model parameters chosen as of July 1992 that were used by the Performance Assessment Department of Sandia National Laboratories in its 1992 preliminary performance assessment of the Waste Isolation Pilot Plant (WIPP). Ranges and distributions for about 300 modeling parameters in the current secondary data base are presented in tables for the geologic and engineered barriers, global materials (e.g., fluid properties), and agents that act upon the WIPP disposal system such as climate variability and human-intrusion boreholes. The 49 parameters sampled in the 1992 Preliminary Performance Assessment are given special emphasis with tables and graphics that provide insight and sources of data for each parameter.

Not Available

1992-12-29T23:59:59.000Z

306

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

SciTech Connect (OSTI)

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

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

1998-12-31T23:59:59.000Z

307

Need to understand "Uncertainty Assessment" in the system development modeling process  

E-Print Network [OSTI]

In the early stage of software life cycle project manager are inefficient to estimate the effort, schedule, cost estimation and its development approach .This in turn, confuses the manager to bid effectively on software project and choose incorrect development approach. That will directly effect on productivity cycle and increase level of uncertainty. This becomes a strong cause of project failure. So to avoid such problem if we know level and sources of uncertainty in model design, It will directive the developer to design accurate software cost and schedule estimation. Which are essential for software project success . However once the required efforts have estimated, little is done to recalibrate and reduce the uncertainty of the initial estimates. This paper demonstrates terminology and typology of uncertainty is presented together with a framework for the modeling process, Brief reviews have been made of 14 different (partly complementary) methods commonly used in uncertainty assessment its interaction w...

Kardile, Vilas Vasantrao

2011-01-01T23:59:59.000Z

308

PORFLOW MODELING FOR A PRELIMINARY ASSESSMENT OF THE PERFORMANCE OF NEW SALTSTONE DISPOSAL UNIT DESIGNS  

SciTech Connect (OSTI)

At the request of Savannah River Remediation (SRR), SRNL has analyzed the expected performance obtained from using seven 32 million gallon Saltstone Disposal Units (SDUs) in the Z-Area Saltstone Disposal Facility (SDF) to store future saltstone grout. The analysis was based on preliminary SDU final design specifications. The analysis used PORFLOW modeling to calculate the release of 20 radionuclides from an SDU and transport of the radionuclides and daughters through the vadose zone. Results from this vadose zone analysis were combined with previously calculated releases from existing saltstone vaults and FDCs and a second PORFLOW model run to calculate aquifer transport to assessment points located along a boundary 100 m from the nearest edge of the SDF sources. Peak concentrations within 12 sectors spaced along the 100 m boundary were determined over a period of evaluation extending 20,000 years after SDF closure cap placement. These peak concentrations were provided to SRR to use as input for dose calculations.

Smith, F.

2012-08-06T23:59:59.000Z

309

Assessment of near-surface dissolution at and near the Waste Isolation Pilot Plant (WIPP), southeastern New Mexico  

SciTech Connect (OSTI)

The area at and near the WIPP site was examined for evidence of karst development on the geomorphic surface encompassing the site. Certain surficial depressions of initial concern were identified as blowouts in sand dune fields (shallow features unrelated to karstification). An ancient stream system active more than 500,000 yr ago contained more water than any system since. During that time (Gatuna, Middle Pleistocene), many karst features such as Clayton Basin and Nash Draw began to form in the region. Halite was probably dissolved from parts of the Rustler Formation at that time. Dissolution of halite and gypsum from intervals encountered in Borehole WIPP-33 west of the WIPP site occurred during later Pleistocene time (i.e., <450,000 yr ago). However, there is no evidence of active near-surface dissolution within a belt to the east of WIPP-33 in the vicinity of the WIPP shaft. 26 refs., 11 figs., 1 tab.

Bachman, G.O.

1985-07-01T23:59:59.000Z

310

Modeling Electrochemical Decomposition of Fluoroethylene Carbonate on Silicon Anode Surfaces in Lithium Ion Batteries  

E-Print Network [OSTI]

Fluoroethylene carbonate (FEC) shows promise as an electrolyte additive for improving passivating solid-electrolyte interphase (SEI) films on silicon anodes used in lithium ion batteries (LIB). We apply density functional theory (DFT), ab initio molecular dynamics (AIMD), and quantum chemistry techniques to examine excess-electron-induced FEC molecular decomposition mechanisms that lead to FEC-modified SEI. We consider one- and two-electron reactions using cluster models and explicit interfaces between liquid electrolyte and model Li(x)Si(y) surfaces, respectively. FEC is found to exhibit more varied reaction pathways than unsubstituted ethylene carbonate. The initial bond-breaking events and products of one- and two-electron reactions are qualitatively similar, with a fluoride ion detached in both cases. However, most one-electron products are charge-neutral, not anionic, and may not coalesce to form effective Li+-conducting SEI unless they are further reduced or take part in other reactions. The implications of these reactions to silicon-anode based LIB are discussed.

Kevin Leung; Susan B. Rempe; Michael E. Foster; Yuguang Ma; Julibeth M. Martinez del la Hoz; Na Sai; Perla B. Balbuena

2014-01-17T23:59:59.000Z

311

Surface spectroscopic characterization of oxide thin films and bimetallic model catalysts  

E-Print Network [OSTI]

. The interaction of metal clusters (Ag) with defects was examined by work function measurements. On various Pd related bimetallic alloy surfaces, CO chemisorption behavior was addressed by IRAS and TPD. Observed changes in the surface chemical properties during...

Wei, Tao

2009-05-15T23:59:59.000Z

312

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

E-Print Network [OSTI]

explicit manner, while life cycle assessment (LCA) does notuse impacts in life cycle assessment. Int J LCA 11(5):363–Int J LCA Kim S, Dale BE (2005b) Life cycle assessment of

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

2010-01-01T23:59:59.000Z

313

Wildfire Risk Mapping over the State of Mississippi: Land Surface Modeling Approach  

SciTech Connect (OSTI)

Three fire risk indexes based on soil moisture estimates were applied to simulate wildfire probability over the southern part of Mississippi using the logistic regression approach. The fire indexes were retrieved from: (1) accumulated difference between daily precipitation and potential evapotranspiration (P-E); (2) top 10 cm soil moisture content simulated by the Mosaic land surface model; and (3) the Keetch-Byram drought index (KBDI). The P-E, KBDI, and soil moisture based indexes were estimated from gridded atmospheric and Mosaic-simulated soil moisture data available from the North American Land Data Assimilation System (NLDAS-2). Normalized deviations of these indexes from the 31-year mean (1980-2010) were fitted into the logistic regression model describing probability of wildfires occurrence as a function of the fire index. It was assumed that such normalization provides more robust and adequate description of temporal dynamics of soil moisture anomalies than the original (not normalized) set of indexes. The logistic model parameters were evaluated for 0.25 x0.25 latitude/longitude cells and for probability representing at least one fire event occurred during 5 consecutive days. A 23-year (1986-2008) forest fires record was used. Two periods were selected and examined (January mid June and mid September December). The application of the logistic model provides an overall good agreement between empirical/observed and model-fitted fire probabilities over the study area during both seasons. The fire risk indexes based on the top 10 cm soil moisture and KBDI have the largest impact on the wildfire odds (increasing it by almost 2 times in response to each unit change of the corresponding fire risk index during January mid June period and by nearly 1.5 times during mid September-December) observed over 0.25 x0.25 cells located along the state of Mississippi Coast line. This result suggests a rather strong control of fire risk indexes on fire occurrence probability over this region.

Cooke, William H. [Mississippi State University (MSU); Mostovoy, Georgy [Mississippi State University (MSU); Anantharaj, Valentine G [ORNL; Jolly, W. Matt [USDA Forest Service

2012-01-01T23:59:59.000Z

314

CONTAIN code analyses of direct containment heating (DCH) experiments: Model assessment and phenomenological interpretation  

SciTech Connect (OSTI)

Models for direct containment heating (DCH) in the CONTAIN code for severe accident analysis have been reviewed and a standard input prescription for their use has been defined. The code has been exercised against a large subset of the available DCH data base. Generally good agreement with the experimental results for containment pressurization ({Delta}P) and hydrogen generation has been obtained. Extensive sensitivity studies have been performed which permit assessment of many of the strengths and weaknesses of specific model features. These include models for debris transport and trapping, DCH heat transfer and chemistry, atmosphere-structure heat transfer, interactions between nonairborne debris and blowdown steam, potential effects of debris-water interactions, and hydrogen combustion under DCH conditions. Containment compartmentalization is an important DCH mitigator in the calculations, in agreement with experimental results. The CONTAIN model includes partially parametric treatments for some processes that are not well understood. The importance of the associated uncertainties depends upon the details of the DCH scenario being analyzed. Recommended sensitivity studies are summarized that allow the user to obtain a reasonable estimate of the uncertainties in the calculated results.

Williams, D.C.; Griffith, R.O.; Tadios, E.L.; Washington, K.E.

1995-05-12T23:59:59.000Z

315

Simulating the Transverse Ising Model on a Quantum Computer: Error Correction with the Surface Code  

E-Print Network [OSTI]

of a fault- tolerant quantum computer. The surface code approach has one of the highest known tolerable error of the surface code is four orders of magnitude higher than the concatenation code, building a quantum computer implementation, a new approach to building a quantum computer with the surface code (which is a kind

Geller, Michael R.

316

E-Print Network 3.0 - assessment models final Sample Search Results  

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

O N S E C U R I T Y INITIAL PUBLIC DRAFT Security Assessment Provider... Requirements and Customer Responsibilities: Building a Security Assessment Credentialing Program for...

317

CEMENTITIOUS BARRIERS MODELING FOR PERFORMANCE ASSESSMENTS OF SHALLOW LAND BURIAL OF LOW LEVEL RADIOACTIVE WASTE - 9243  

SciTech Connect (OSTI)

The Cementitious Barriers Partnership (CBP) was created to develop predictive capabilities for the aging of cementitious barriers over long timeframes. The CBP is a multi-agency, multi-national consortium working under a U.S. Department of Energy (DOE) Environmental Management (EM-21) funded Cooperative Research and Development Agreement (CRADA) with the Savannah River National Laboratory (SRNL) as the lead laboratory. Members of the CBP are SRNL, Vanderbilt University, the U.S. Nuclear Regulatory Commission (USNRC), National Institute of Standards and Technology (NIST), SIMCO Technologies, Inc. (Canada), and the Energy Research Centre of the Netherlands (ECN). A first step in developing advanced tools is to determine the current state-of-the-art. A review has been undertaken to assess the treatment of cementitious barriers in Performance Assessments (PA). Representatives of US DOE sites which have PAs for their low level waste disposal facilities were contacted. These sites are the Idaho National Laboratory, Oak Ridge National Laboratory, Los Alamos National Laboratory, Nevada Test Site, and Hanford. Several of the more arid sites did not employ cementitious barriers. Of those sites which do employ cementitious barriers, a wide range of treatment of the barriers in a PA was present. Some sites used conservative, simplistic models that even though conservative still showed compliance with disposal limits. Other sites used much more detailed models to demonstrate compliance. These more detailed models tend to be correlation-based rather than mechanistically-based. With the US DOE's Low Level Waste Disposal Federal Review Group (LFRG) moving towards embracing a risk-based, best estimate with an uncertainties type of analysis, the conservative treatment of the cementitious barriers seems to be obviated. The CBP is creating a tool that adheres to the LFRG chairman's paradigm of continuous improvement.

Taylor, G

2009-01-09T23:59:59.000Z

318

Assessment of managed aquifer recharge site suitability and influence using a GIS and3 numerical modeling4  

E-Print Network [OSTI]

" for20 MAR. Results from the GIS analysis were used with a regional groundwater model to assess the groundwater flowing to the ocean over the long term. Modeling results28 illustrate considerable variability evaluation of options for32 enhancing groundwater resources.33 34 1. Introduction35 Groundwater

Fisher, Andrew

319

Testing, Modeling, and Monitoring to Enable Simpler, Cheaper, Longer-lived Surface Caps  

SciTech Connect (OSTI)

Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone's back yard); most of these storage sites include a surface barrier (cap) to prevent downward water migration. Some of the hazards will persist indefinitely. As society and regulators have demanded additional proof that caps are robust against more threats and for longer time periods, the caps have become increasingly complex and expensive. As in other industries, increased complexity will eventually increase the difficulty in estimating performance, in monitoring system/component performance, and in repairing or upgrading barriers as risks are managed. An approach leading to simpler, less expensive, longer-lived, more manageable caps is needed. Our project, which started in April 2002, aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late). The knowledge gained and the capabilities built will help verify the adequacy of past remedial decisions, improve barrier management, and enable improved solutions for future decisions. We believe it will be possible to develop simpler, longer-lived, less expensive caps that are easier to monitor, manage, and repair. The project is planned to: (a) improve the knowledge of degradation mechanisms in times shorter than service life; (b) improve modeling of barrier degradation dynamics; (c) develop sensor systems to identify early degradation; and (d) provide a better basis for developing and testing of new barrier systems. This project combines selected exploratory studies (benchtop and field scale), coupled effects accelerated aging testing at the intermediate meso-scale, testing of new monitoring concepts, and modeling of dynamic systems. The emphasis on meso-scale (coupled) tests, accelerated effects testing, and dynamic modeling differentiates the project from other efforts, while simultaneously building on that body of knowledge. The performance of evapotranspiration, capillary, and grout-based barriers is being examined. To date, the project can report new approaches to the problem, building new experimental and modeling capabilities, and a few preliminary results.

Piet, S. J.; Breckenridge, R. P.; Burns, D. E.

2003-02-25T23:59:59.000Z

320

Testing, Modeling, and Monitoring to Enable Simpler, Cheaper, Longer-Lived Surface Caps  

SciTech Connect (OSTI)

Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone’s back yard); most of these storage sites include a surface barrier (cap) to prevent downward water migration. Some of the hazards will persist indefinitely. As society and regulators have demanded additional proof that caps are robust against more threats and for longer time periods, the caps have become increasingly complex and expensive. As in other industries, increased complexity will eventually increase the difficulty in estimating performance, in monitoring system/component performance, and in repairing or upgrading barriers as risks are managed. An approach leading to simpler, less expensive, longer-lived, more manageable caps is needed. Our project, which started in April 2002, aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late). The knowledge gained and the capabilities built will help verify the adequacy of past remedial decisions, improve barrier management, and enable improved solutions for future decisions. We believe it will be possible to develop simpler, longer-lived, less expensive caps that are easier to monitor, manage, and repair. The project is planned to: a) improve the knowledge of degradation mechanisms in times shorter than service life; b) improve modeling of barrier degradation dynamics; c) develop sensor systems to identify early degradation; and d) provide a better basis for developing and testing of new barrier systems. This project combines selected exploratory studies (benchtop and field scale), coupled effects accelerated aging testing at the intermediate meso-scale, testing of new monitoring concepts, and modeling of dynamic systems. The emphasis on meso-scale (coupled) tests, accelerated effects testing, and dynamic modeling differentiates the project from other efforts, while simultaneously building on that body of knowledge. The performance of evapotranspiration, capillary, and grout-based barriers is being examined. To date, the project can report new approaches to the problem, building new experimental and modeling capabilities, and a few preliminary results.

Piet, Steven James; Breckenridge, Robert Paul; Burns, Douglas Edward

2003-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" 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

Model for cradle-to-gate life cycle assessment of clinker production  

SciTech Connect (OSTI)

A model for input- and technology-dependent cradle-to-gate life cycle assessments (LCA) was constructed to quantify emissions and resource consumption of various clinker production options. The model was compiled using data of more than 100 clinker production lines and complemented with literature data and best judgment from experts. It can be applied by the cement industry for the selection of alternative fuels and raw materials (AFR) and by authorities for decision-support regarding the permission of waste co-processing in cement kilns. In the field of sustainable construction, the model can be used to compare clinker production options. Two case studies are presented. First, co-processing of four different types of waste is analyzed at a modern precalciner kiln system. Second, clinker production is compared between five kiln systems. Results show that the use of waste (tires, prepared industrial waste, dried sewage sludge, blast furnace slag) led to reduced greenhouse gas emissions, decreased resource consumption, and mostly to reduced aggregated environmental impacts. Regarding the different kiln systems, the environmental impact generally increased with decreasing energy efficiency. 35 refs., 2 figs., 2 tabs.

Michael Elias Boesch; Annette Koehler; Stefanie Hellweg [ETH Zurich, Zurich (Switzerland). Institute of Environmental Engineering

2009-10-01T23:59:59.000Z

322

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

SciTech Connect (OSTI)

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

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

2013-06-21T23:59:59.000Z

323

Improving Surface Radiation in a Satellite-Based Physical Model (Poster)  

SciTech Connect (OSTI)

This poster provides an overview of the solar resource assessment work needed to achieve high penetrations of concentrating solar power or photovoltaics on the grid.

Sengupta, M.; Habte, A.; Gotseff, P.

2013-10-01T23:59:59.000Z

324

Trace Metal Bioremediation: Assessment of Model Components from Laboratory and Field Studies to Identify Critical Variables  

SciTech Connect (OSTI)

The objective of this project was to gain an insight into the modeling support needed for the understanding, design, and operation of trace metal/radionuclide bioremediation. To achieve this objective, a workshop was convened to discuss the elements such a model should contain. A ''protomodel'' was developed, based on the recommendations of the workshop, and was used to perform sensitivity analysis as well as some preliminary simulations in support for bioremediation test experiments at UMTRA sites. To simulate the numerous biogeochemical processes that will occur during the bioremediation of uranium contaminated aquifers, a time-dependent one-dimensional reactive transport model has been developed. The model consists of a set of coupled, steady state mass balance equations, accounting for advection, diffusion, dispersion, and a kinetic formulation of the transformations affecting an organic substrate, electron acceptors, corresponding reduced species, and uranium. This set of equations is solved numerically, using a finite element scheme. The redox conditions of the domain are characterized by estimating the pE, based on the concentrations of the dominant terminal electron acceptor and its corresponding reduced specie. This pE and the concentrations of relevant species are passed to a modified version of MINTEQA2, which calculates the speciation and solubilities of the species of interest. Kinetics of abiotic reactions are described as being proportional to the difference between the actual and equilibrium concentration. A global uncertainty assessment, determined by Random Sampling High Dimensional Model Representation (RS-HDMR), was performed to attain a phenomenological understanding of the origins of output variability and to suggest input parameter refinements as well as to provide guidance for field experiments to improve the quality of the model predictions. Results indicated that for the usually high nitrate contents found ate many DOE sites, overall bioremediation of trace metals was highly sensitive to the formulation of the denitrification process. Simulations were performed to illustrate the effect of biostimulation on the transport and precipitation of uranium in the subsurface, at conditions equivalent to UMTRA sites. These simulations predicted that uranium would precipitate in bands that are located relatively close to the acetate injection well. The simulations also showed the importance of properly determining U(IV) oxidative dissolution rates, in order to assess the stability of precipitates once oxygenated water reenters the aquifer after bioremediation is discontinued. The objective of this project was to provide guidance to NABIR's Systems Integration Element, on the development of models to simulate the bioremediation of trace metals and radionuclides. Such models necessarily need to integrate hydrological, geochemical, and microbiological processes. In order to gain a better understanding of the key processes that such a model should contain, it was deemed desirable to convene a workshop with experts from these different fields. The goal was to obtain a preliminary consensus on the required level of detail for the formulations of these different chemical, physical, and microbiological processes. The workshop was held on December 18, 1998.

Peter Jaffe; Herschel Rabitz

2003-02-14T23:59:59.000Z

325

The motion of kelp blades and the surface renewal model Ivy Huang, Jeffrey Rominger, and Heidi Nepf*  

E-Print Network [OSTI]

The motion of kelp blades and the surface renewal model Ivy Huang, Jeffrey Rominger, and Heidi Nepf* Massachusetts Institute of Technology, Cambridge, Massachusetts Abstract We consider how the flapping of kelp kelp blades of Laminaria saccharina, Macrocystis pyrifera, and Nereocystis luetkeana under uni

Nepf, Heidi M.

326

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

E-Print Network [OSTI]

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

Small, Eric

327

Mechanical models of fracture reactivation and slip on bedding surfaces during folding of the asymmetric anticline at Sheep Mountain, Wyoming  

E-Print Network [OSTI]

Mechanical models of fracture reactivation and slip on bedding surfaces during folding June 2008 Accepted 5 June 2008 Available online 13 June 2008 Keywords: Fold Fracture reactivation Bed methods to investigate the reactivation of fractures (opening and shearing) and the development of bedding

Borja, Ronaldo I.

328

RAMI4PILPS: An intercomparison of formulations for the partitioning of solar radiation in land surface models  

E-Print Network [OSTI]

RAMI4PILPS: An intercomparison of formulations for the partitioning of solar radiation in land for the partitioning of solar radiation in land surface models, J. Geophys. Res., 116, G02019, doi:10.1029/2010JG001511 [e.g., Zeng et al., 2000; Dai et al., 2004]. The partitioning of solar radiation between

Ni-Meister, Wenge

329

Modeling  

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

330

Repository Integration Program: RIP performance assessment and strategy evaluation model theory manual and user`s guide  

SciTech Connect (OSTI)

This report describes the theory and capabilities of RIP (Repository Integration Program). RIP is a powerful and flexible computational tool for carrying out probabilistic integrated total system performance assessments for geologic repositories. The primary purpose of RIP is to provide a management tool for guiding system design and site characterization. In addition, the performance assessment model (and the process of eliciting model input) can act as a mechanism for integrating the large amount of available information into a meaningful whole (in a sense, allowing one to keep the ``big picture`` and the ultimate aims of the project clearly in focus). Such an integration is useful both for project managers and project scientists. RIP is based on a `` top down`` approach to performance assessment that concentrates on the integration of the entire system, and utilizes relatively high-level descriptive models and parameters. The key point in the application of such a ``top down`` approach is that the simplified models and associated high-level parameters must incorporate an accurate representation of their uncertainty. RIP is designed in a very flexible manner such that details can be readily added to various components of the model without modifying the computer code. Uncertainty is also handled in a very flexible manner, and both parameter and model (process) uncertainty can be explicitly considered. Uncertainty is propagated through the integrated PA model using an enhanced Monte Carlo method. RIP must rely heavily on subjective assessment (expert opinion) for much of its input. The process of eliciting the high-level input parameters required for RIP is critical to its successful application. As a result, in order for any project to successfully apply a tool such as RIP, an enormous amount of communication and cooperation must exist between the data collectors, the process modelers, and the performance. assessment modelers.

NONE

1995-11-01T23:59:59.000Z

331

EXPERIMENTAL DESIGN APPLICATIONS FOR MODELING AND ASSESSING CARBON DIOXIDE SEQUESTRATION IN SALINE AQUIFERS  

SciTech Connect (OSTI)

This project was a computer modeling effort to couple reservoir simulation and ED/RSM using Sensitivity Analysis, Uncertainty Analysis, and Optimization Methods, to assess geologic, geochemical, geomechanical, and rock-fluid effects and factors on CO2 injectivity, capacity, and plume migration. The project objective was to develop proxy models to simplify the highly complex coupled geochemical and geomechanical models in the utilization and storage of CO2 in the subsurface. The goals were to investigate and prove the feasibility of the ED/RSM processes and engineering development, and bridge the gaps regarding the uncertainty and unknowns of the many geochemical and geomechanical interacting parameters in the development and operation of anthropogenic CO2 sequestration and storage sites. The bottleneck in this workflow is the high computational effort of reactive transport simulation models and large number of input variables to optimize with ED/RSM techniques. The project was not to develop the reactive transport, geomechanical, or ED/RSM software, but was to use what was commercially and/or publically available as a proof of concept to generate proxy or surrogate models. A detailed geologic and petrographic mineral assemblage and geologic structure of the doubly plunging anticline was defined using the USDOE RMOTC formations of interest data (e.g., Lower Sundance, Crow Mountain, Alcova Limestone, and Red Peak). The assemblage of 23 minerals was primarily developed from literature data and petrophysical (well log) analysis. The assemblage and structure was input into a commercial reactive transport simulator to predict the effects of CO2 injection and complex reactions with the reservoir rock. Significant impediments were encountered during the execution phase of the project. The only known commercial reactive transport simulator was incapable of simulating complex geochemistry modeled in this project. Significant effort and project funding was expended to determine the limitations of both the commercial simulator and the Lawrence Berkeley National Laboratory (LBNL) R&D simulator, TOUGHREACT available to the project. A simplified layer cake model approximating the volume of the RMOTC targeted reservoirs was defined with 1-3 minerals eventually modeled with limited success. Modeling reactive transport in porous media requires significant computational power. In this project, up to 24 processors were used to model a limited mineral set of 1-3 minerals. In addition, geomechanical aspects of injecting CO2 into closed, semi-open, and open systems in various well completion methods was simulated. Enhanced Oil Recovery (EOR) as a storage method was not modeled. A robust and stable simulation dataset or base case was developed and used to create a master dataset with embedded instructions for input to the ED/RSM software. Little success was achieved toward the objective of the project using the commercial simulator or the LBNL simulator versions available during the time of this project. Several hundred realizations were run with the commercial simulator and ED/RSM software, most having convergence problems and terminating prematurely. A proxy model for full field CO2 injection sequestration utilization and storage was not capable of being developed with software available for this project. Though the chemistry is reasonably known and understood, based on the amount of effort and huge computational time required, predicting CO2 sequestration storage capacity in geologic formations to within the program goals of ±30% proved unsuccessful.

Rogers, John

2014-08-31T23:59:59.000Z

332

AURORA: A FORTRAN program for modeling well stirred plasma and thermal reactors with gas and surface reactions  

SciTech Connect (OSTI)

The AURORA Software is a FORTRAN computer program that predicts the steady-state or time-averaged properties of a well mixed or perfectly stirred reactor for plasma or thermal chemistry systems. The software was based on the previously released software, SURFACE PSR which was written for application to thermal CVD reactor systems. AURORA allows modeling of non-thermal, plasma reactors with the determination of ion and electron concentrations and the electron temperature, in addition to the neutral radical species concentrations. Well stirred reactors are characterized by a reactor volume, residence time or mass flow rate, heat loss or gas temperature, surface area, surface temperature, the incoming temperature and mixture composition, as well as the power deposited into the plasma for non-thermal systems. The model described here accounts for finite-rate elementary chemical reactions both in the gas phase and on the surface. The governing equations are a system of nonlinear algebraic relations. The program solves these equations using a hybrid Newton/time-integration method embodied by the software package TWOPNT. The program runs in conjunction with the new CHEMKIN-III and SURFACE CHEMKIN-III packages, which handle the chemical reaction mechanisms for thermal and non-thermal systems. CHEMKIN-III allows for specification of electron-impact reactions, excitation losses, and elastic-collision losses for electrons.

Meeks, E.; Grcar, J.F.; Kee, R.J. [Sandia National Labs., Livermore, CA (United States). Thermal and Plasma Processes Dept.] [Sandia National Labs., Livermore, CA (United States). Thermal and Plasma Processes Dept.; Moffat, H.K. [Sandia National Labs., Albuquerque, NM (United States). Surface Processing Sciences Dept.] [Sandia National Labs., Albuquerque, NM (United States). Surface Processing Sciences Dept.

1996-02-01T23:59:59.000Z

333

Retrieving snow mass from GRACE terrestrial water storage change with a land surface model  

E-Print Network [OSTI]

by the Advanced Very High Resolution Radio- meter (AVHRR) is decreasing since middle 1980s in response to global are variations in surface albedo and surface energy budgets, sensible heat and water vapor fluxes-chan- nel Microwave Radiometer (SMMR) and the Advanced Microwave Scanning Radiometer (AMSR) provide a capa

Yang, Zong-Liang

334

Progress In Electromagnetics Research B, Vol. 25, 293314, 2010 IMPROVED ANALYTICAL MODEL FOR SURFACE-  

E-Print Network [OSTI]

a large influence on the airgap magnetic field distribution and therefore on the motor performances (noise FOR SURFACE- MOUNTED PM MOTORS CONSIDERING SLOTTING EFFECTS AND ARMATURE REACTION T. Lubin, S. Mezani, and A of the magnetic field distribution in surface-mounted permanent-magnet (PM) motors for any pole and slot

Boyer, Edmond

336

Modeling the Effects of Irrigation on Land Surface Fluxes and States over the Conterminous United States: Sensitivity to Input Data and Model Parameters  

SciTech Connect (OSTI)

Previous studies on irrigation impacts on land surface fluxes/states were mainly conducted as sensitivity experiments, with limited analysis of uncertainties from the input data and model irrigation schemes used. In this study, we calibrated and evaluated the performance of irrigation water use simulated by the Community Land Model version 4 (CLM4) against observations from agriculture census. We investigated the impacts of irrigation on land surface fluxes and states over the conterminous United States (CONUS) and explored possible directions of improvement. Specifically, we found large uncertainty in the irrigation area data from two widely used sources and CLM4 tended to produce unrealistically large temporal variations of irrigation demand for applications at the water resources region scale over CONUS. At seasonal to interannual time scales, the effects of irrigation on surface energy partitioning appeared to be large and persistent, and more pronounced in dry than wet years. Even with model calibration to yield overall good agreement with the irrigation amounts from the National Agricultural Statistics Service (NASS), differences between the two irrigation area datasets still dominate the differences in the interannual variability of land surface response to irrigation. Our results suggest that irrigation amount simulated by CLM4 can be improved by (1) calibrating model parameter values to account for regional differences in irrigation demand and (2) accurate representation of the spatial distribution and intensity of irrigated areas.

Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong; Sacks, William J.; Lei, Huimin; Leung, Lai-Yung R.

2013-09-16T23:59:59.000Z

337

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

SciTech Connect (OSTI)

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

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

2014-05-13T23:59:59.000Z

338

Assessment of CCFL model of RELAP5/MOD3 against simple vertical tubes and rod bundle tests. International Agreement Report  

SciTech Connect (OSTI)

The CCFL model used in RELAP5/MOD3 version 5m5 has been assessed against simple vertical tubes and bundle tests performed at a facility of Korea Atomic Energy Research Institute. The effect of changes in tube diameter and nodalization of tube section were investigated. The roles of interfacial drags on the flooding characteristics are discussed. Differences between the calculation and the experiment are also discussed. A comparison between model assessment results and the test data showed that the calculated value lay well on the experimental flooding curve specified by user, but the pressure jump before onset of flooding was not calculated.

Cho, S.; Arne, N. [Korea Electric Power Corp., Taejon (KR). Research Center; Chung, B.D.; Kim, H.J. [Korea Inst. of Nuclear Safety, Taejon (KR)

1993-06-01T23:59:59.000Z

339

Sensitivity of Surface Flux Simulations to Hydrologic Parameters Based on an Uncertainty Quantification Framework Applied to the Community Land Model  

SciTech Connect (OSTI)

Uncertainties in hydrologic parameters could have significant impacts on the simulated water and energy fluxes and land surface states, which will in turn affect atmospheric processes and the carbon cycle. Quantifying such uncertainties is an important step toward better understanding and quantification of uncertainty of integrated earth system models. In this paper, we introduce an uncertainty quantification (UQ) framework to analyze sensitivity of simulated surface fluxes to selected hydrologic parameters in the Community Land Model (CLM4) through forward modeling. Thirteen flux tower footprints spanning a wide range of climate and site conditions were selected to perform sensitivity analyses by perturbing the parameters identified. In the UQ framework, prior information about the parameters was used to quantify the input uncertainty using the Minimum-Relative-Entropy approach. The quasi-Monte Carlo approach was applied to generate samples of parameters on the basis of the prior pdfs. Simulations corresponding to sampled parameter sets were used to generate response curves and response surfaces and statistical tests were used to rank the significance of the parameters for output responses including latent (LH) and sensible heat (SH) fluxes. Overall, the CLM4 simulated LH and SH show the largest sensitivity to subsurface runoff generation parameters. However, study sites with deep root vegetation are also affected by surface runoff parameters, while sites with shallow root zones are also sensitive to the vadose zone soil water parameters. Generally, sites with finer soil texture and shallower rooting systems tend to have larger sensitivity of outputs to the parameters. Our results suggest the necessity of and possible ways for parameter inversion/calibration using available measurements of latent/sensible heat fluxes to obtain the optimal parameter set for CLM4. This study also provided guidance on reduction of parameter set dimensionality and parameter calibration framework design for CLM4 and other land surface models under different hydrologic and climatic regimes.

Hou, Zhangshuan; Huang, Maoyi; Leung, Lai-Yung R.; Lin, Guang; Ricciuto, Daniel M.

2012-08-10T23:59:59.000Z

340

Physica 65 (1973) 73-88 0 North-Holland Publishing Co. SURFACE TENSION IN THE TWO-DIMENSIONAL ISING MODEL  

E-Print Network [OSTI]

Physica 65 (1973) 73-88 0 North-Holland Publishing Co. SURFACE TENSION IN THE TWO-DIMENSIONAL ISING of surface tension between oppositely magnetised phases in the two-dimensional Ising model. With nearest?) defined and calculated exactly a surface tension. This was later shown by Fisher and Ferdinand5

Roma "La Sapienza", Università di

Note: This page contains sample records for the topic "models assessing surface" 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

Refinement of a semi-empirical model for the microwave emissivity of the sea surface as a function of wind speed  

E-Print Network [OSTI]

as the wind speed increases-instead of being switched on at 7 m/s. These changes yield an improved sea surface model that is within 2% of the sea surface emissivity given by the Wentz sea surface emissivity functions....

Kohn, David Jacob

2012-06-07T23:59:59.000Z

342

E-Print Network 3.0 - assessment modeling productivity Sample...  

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

1; x has priority value and L is level of decision tree Summary: or productive 11f cough -> assess smoking history 11g cough -> assess cyanosis STATE Information If cough...

343

Framework for Modeling the Uncertainty of Future Events in Life Cycle Assessment  

E-Print Network [OSTI]

INTRODUCTION Life Cycle Assessment (LCA) is a leadingLife Cycle Assessment by including predictable disruptions to the life cycle, thereby increasing the meaningfulness of LCALife Cycle Assessment is a very important factor to consider in order to ensure the accuracy of estimated emissions and meaningfulness of LCA

Chen, Yi-Fen; Simon, Rachel; Dornfeld, David

2013-01-01T23:59:59.000Z

344

TransCom model simulations of CH? and related species: linking transport, surface flux and chemical loss with CH? variability in the troposphere and lower stratosphere  

E-Print Network [OSTI]

A chemistry-transport model (CTM) intercomparison experiment (TransCom-CH?) has been designed to investigate the roles of surface emissions, transport and chemical loss in simulating the global methane distribution. Model ...

Patra, P. K.

345

High-Resolution Modeling to Assess Tropical Cyclone Activity in Future Climate Regimes  

SciTech Connect (OSTI)

Applied research is proposed with the following objectives: (i) to determine the most likely level of tropical cyclone intensity and frequency in future climate regimes, (ii) to provide a quantitative measure of uncertainty in these predictions, and (iii) to improve understanding of the linkage between tropical cyclones and the planetary-scale circulation. Current mesoscale weather forecasting models, such as the Weather Research and Forecasting (WRF) model, are capable of simulating the full intensity of tropical cyclones (TC) with realistic structures. However, in order to accurately represent both the primary and secondary circulations in these systems, model simulations must be configured with sufficient resolution to explicitly represent convection (omitting the convective parameterization scheme). Most previous numerical studies of TC activity at seasonal and longer time scales have not utilized such explicit convection (EC) model runs. Here, we propose to employ the moving nest capability of WRF to optimally represent TC activity on a seasonal scale using a downscaling approach. The statistical results of a suite of these high-resolution TC simulations will yield a realistic representation of TC intensity on a seasonal basis, while at the same time allowing analysis of the feedback that TCs exert on the larger-scale climate system. Experiments will be driven with analyzed lateral boundary conditions for several recent Atlantic seasons, spanning a range of activity levels and TC track patterns. Results of the ensemble of WRF simulations will then be compared to analyzed TC data in order to determine the extent to which this modeling setup can reproduce recent levels of TC activity. Next, the boundary conditions (sea-surface temperature, tropopause height, and thermal/moisture profiles) from the recent seasons will be altered in a manner consistent with various future GCM/RCM scenarios, but that preserves the large-scale shear and incipient disturbance activity. This will allow (i) a direct comparison of future TC activity that could be expected for an active or inactive season in an altered climate regime, and (ii) a measure of the level of uncertainty and variability in TC activity resulting from different carbon emission scenarios.

Lackmann, Gary

2013-06-10T23:59:59.000Z

346

E-Print Network 3.0 - actuator surface model Sample Search Results  

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

needs to be performed, it is evident that the flow local to plasma actuators on an aerodynamic surface... actuation due to the weaker electric field above the flow facing...

347

Modeling of three-dimensional viscoelastic flows with free surfaces using a finite element method  

E-Print Network [OSTI]

A framework and code have been developed to simulate fiber and film processes; the code can handle three-dimensional, isothermal, incompressible, creeping flow of a Giesekus fluid with free surfaces at infinite capillary ...

Adrian, David Joseph

2010-01-01T23:59:59.000Z

348

Calibration of an EnergyPlus Building Energy Model to Assess the Impact of Demand Response Measures  

E-Print Network [OSTI]

1 Karine Lavigne Simon Sansregret Ahmed DaoudLouis-Alexandre Leclaire CALIBRATION OF AN ENERGYPLUS BUILDING ENERGY MODEL TO ASSESS THE IMPACT OF DEMAND RESPONSE MEASURES ICEBO 2013, Montr?al Groupe ? Technologie2 ICEBO-2013 Contextualization... ICEBO-2013 Groupe ? Technologie Calibrated Results 22 ICEBO-2013 12 Groupe ? Technologie Conclusion 23 ICEBO-2013 > Calibrating model for a demand response objective : Challenging and High Effort > Capturing building and human erratic behaviour...

Lavigne, K.; Sansregret, S.; Daoud, A.; Leclair, L. A.

2013-01-01T23:59:59.000Z

349

IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 22, NO. 1, FEBRUARY 2007 85 A Reinforcement Learning Model to Assess Market  

E-Print Network [OSTI]

IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 22, NO. 1, FEBRUARY 2007 85 A Reinforcement Learning Model to Assess Market Power Under Auction-Based Energy Pricing Vishnuteja Nanduri, Student Member, IEEE, and Tapas K. Das, Member, IEEE Abstract--Auctions serve as a primary pricing mechanism in various market

Tesfatsion, Leigh

350

A Multi-State Model for the Reliability Assessment of a Distributed Generation System via Universal Generating Function  

E-Print Network [OSTI]

, Milan, Italy, Dipartimento di Energia Enrico.zio@polimi.it Abstract The current and future developments renewable technology (e.g. wind or solar, etc.) whose behavior is described by a binary state, working assessment, multi-state modeling, universal generating function #12;2 Notations Solar irradiance Total number

Boyer, Edmond

351

Assessment of the Value, Impact, and Validity of the Jobs and Economic Development Impacts (JEDI) Suite of Models  

SciTech Connect (OSTI)

The Jobs and Economic Development Impacts (JEDI) models, developed by the National Renewable Energy Laboratory (NREL) for the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), use input-output methodology to estimate gross (not net) jobs and economic impacts of building and operating selected types of renewable electricity generation and fuel plants. This analysis provides the DOE with an assessment of the value, impact, and validity of the JEDI suite of models. While the models produce estimates of jobs, earnings, and economic output, this analysis focuses only on jobs estimates. This validation report includes an introduction to JEDI models, an analysis of the value and impact of the JEDI models, and an analysis of the validity of job estimates generated by JEDI model through comparison to other modeled estimates and comparison to empirical, observed jobs data as reported or estimated for a commercial project, a state, or a region.

Billman, L.; Keyser, D.

2013-08-01T23:59:59.000Z

352

Computer models to support investigations of surface subsidence and associated ground motion induced by underground coal gasification. [STEALTH Codes  

SciTech Connect (OSTI)

Two computer codes compare surface subsidence induced by underground coal gasification at Hoe Creek, Wyoming, and Centralia, Washington. Calculations with the STEALTH explicit finite-difference code are shown to match equivalent, implicit finite-element method solutions for the removal of underground material. Effects of removing roof material, varying elastic constants, investigating thermal shrinkage, and burning multiple coal seams are studied. A coupled, finite-difference continuum rigid-block caving code is used to model underground opening behavior. Numerical techniques agree qualitatively with empirical studies but, so far, underpredict ground surface displacement. The two methods, numerical and empirical, are most effective when used together. It is recommended that the thermal characteristics of coal measure rock be investigated and that additional calculations be carried out to longer times so that cooling influences can be modeled.

Langland, R.T.; Trent, B.C.

1981-01-01T23:59:59.000Z

353

Computer models to support investigations of surface subsidence and associated ground motion induced by underground coal gasification  

SciTech Connect (OSTI)

Two computer codes compare surface subsidence induced by underground coal gasification at Hoe Creek, Wyoming, and Centralia, Washington. Calculations with the STEALTH explicit finite-difference code are shown to match equivalent, implicit finite-element method solutions for the removal of underground material. Effects of removing roof material, varying elastic constants, investigating thermal shrinkage, and burning multiple coal seams are studied. A coupled, finite-difference continuum rigid-block caving code is used to model underground opening behavior. Numerical techniques agree qualitatively with empirical studies but, so far, underpredict ground surface displacement. The two methods, numerical and empirical, are most effective when used together. It is recommended that the thermal characteristics of coal measure rock be investigated and that additional calculations be carried out to longer times so that cooling influences can be modeled.

Trent, B.C.; Langland, R.T.

1981-08-01T23:59:59.000Z

354

ASSESSMENT FOR THE SOUTHWEST  

E-Print Network [OSTI]

SERVICE CLIMATE CHANGE & CULTURAL RESOURCE PLANNING PROGRAM 17 EARTH SYSTEM MODELS 18 CLIMATE ASSESSMENTS

Wong, Pak Kin

355

Modeling and comparative assessment of municipal solid waste gasification for energy production  

SciTech Connect (OSTI)

Highlights: • Study developed a methodology for the evaluation of gasification for MSW treatment. • Study was conducted comparatively for USA, UAE, and Thailand. • Study applies a thermodynamic model (Gibbs free energy minimization) using the Gasify software. • The energy efficiency of the process and the compatibility with different waste streams was studied. - Abstract: Gasification is the thermochemical conversion of organic feedstocks mainly into combustible syngas (CO and H{sub 2}) along with other constituents. It has been widely used to convert coal into gaseous energy carriers but only has been recently looked at as a process for producing energy from biomass. This study explores the potential of gasification for energy production and treatment of municipal solid waste (MSW). It relies on adapting the theory governing the chemistry and kinetics of the gasification process to the use of MSW as a feedstock to the process. It also relies on an equilibrium kinetics and thermodynamics solver tool (Gasify®) in the process of modeling gasification of MSW. The effect of process temperature variation on gasifying MSW was explored and the results were compared to incineration as an alternative to gasification of MSW. Also, the assessment was performed comparatively for gasification of MSW in the United Arab Emirates, USA, and Thailand, presenting a spectrum of socioeconomic settings with varying MSW compositions in order to explore the effect of MSW composition variance on the products of gasification. All in all, this study provides an insight into the potential of gasification for the treatment of MSW and as a waste to energy alternative to incineration.

Arafat, Hassan A., E-mail: harafat@masdar.ac.ae; Jijakli, Kenan

2013-08-15T23:59:59.000Z

356

Research utilization in the building industry: decision model and preliminary assessment  

SciTech Connect (OSTI)

The Research Utilization Program was conceived as a far-reaching means for managing the interactions of the private sector and the federal research sector as they deal with energy conservation in buildings. The program emphasizes a private-public partnership in planning a research agenda and in applying the results of ongoing and completed research. The results of this task support the hypothesis that the transfer of R and D results to the buildings industry can be accomplished more efficiently and quickly by a systematic approach to technology transfer. This systematic approach involves targeting decision makers, assessing research and information needs, properly formating information, and then transmitting the information through trusted channels. The purpose of this report is to introduce elements of a market-oriented knowledge base, which would be useful to the Building Systems Division, the Office of Buildings and Community Systems and their associated laboratories in managing a private-public research partnership on a rational systematic basis. This report presents conceptual models and data bases that can be used in formulating a technology transfer strategy and in planning technology transfer programs.

Watts, R.L.; Johnson, D.R.; Smith, S.A.; Westergard, E.J.

1985-10-01T23:59:59.000Z

357

Modeling  

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

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...

358

NEW EXTENDED DEUTERIUM FRACTIONATION MODEL: ASSESSMENT AT DENSE ISM CONDITIONS AND SENSITIVITY ANALYSIS  

SciTech Connect (OSTI)

Observations of deuterated species are useful in probing the temperature, ionization level, evolutionary stage, chemistry, and thermal history of astrophysical environments. The analysis of data from the Atacama Large Millimeter Array and other new telescopes requires an elaborate model of deuterium fractionation. This paper presents a publicly available chemical network with multi-deuterated species and an extended, up-to-date set of gas-phase and surface reactions. To test this network, we simulate deuterium fractionation in diverse interstellar sources. Two cases of initial abundances are considered: (1) atomic except for H{sub 2} and HD, and (2) molecular from a prestellar core. We reproduce the observed D/H ratios of many deuterated molecules, and sort the species according to their sensitivity to temperature gradients and initial abundances. We find that many multiply deuterated species produced at 10 K retain enhanced D/H ratios at temperatures {approx}< 100 K. We study how recent updates to reaction rates affect calculated D/H ratios, and perform a detailed sensitivity analysis of the uncertainties of the gas-phase reaction rates in the network. We find that uncertainties are generally lower in dark cloud environments than in warm infrared dark clouds and that uncertainties increase with the size of the molecule and number of D-atoms. A set of the most problematic reactions is presented. We list potentially observable deuterated species predicted to be abundant in low- and high-mass star-formation regions.

Albertsson, T.; Semenov, D. A.; Henning, Th. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Vasyunin, A. I.; Herbst, E. [Departments of Chemistry and Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)

2013-08-15T23:59:59.000Z

359

An integral-balance nonlinear model to simulate changes in soil moisture, groundwater and surface runoff dynamics at the hillslope scale  

E-Print Network [OSTI]

An integral-balance nonlinear model to simulate changes in soil moisture, groundwater and surface-state integral-balance model for soil moisture and groundwater dynamics. Development of the model was motivated. Ã? 2014 Elsevier Ltd. All rights reserved. 1. Introduction Recent studies on the modeling

Jay, Laurent O.

360

Language Assessment as a System: Best Practices, Stakeholders, Models, and Testimonials  

E-Print Network [OSTI]

language assessment. Mostafa Majidpour is a second-year PhDcoordinator), and Mostafa Majidpour (current UCLA electricalYoungsoon So and Mostafa Majidpour). When one considers the

Avineri, Netta; Londe, Zsuzsa; Hardacre, Bahiyyih; Carris, Lauren; So, Youngsoon; Majidpour, Mostafa

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" 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

Framework for Modeling the Uncertainty of Future Events in Life Cycle Assessment  

E-Print Network [OSTI]

M. , ( 2010), Product carbon footprint (PCF) assessment ofand Pflueger J. , (2012), Carbon footprint of a dell rackin 65% of the product carbon footprint of a laptop used in

Chen, Yi-Fen; Simon, Rachel; Dornfeld, David

2013-01-01T23:59:59.000Z

362

Model Components of the Certification Framework for Geologic Carbon Sequestration Risk Assessment  

E-Print Network [OSTI]

to two geologic carbon sequestration sites, Energy Procedia,for Geologic Carbon Sequestration Based on Effectivefor geologic carbon sequestration risk assessment, Energy

Oldenburg, Curtis M.

2009-01-01T23:59:59.000Z

363

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

E-Print Network [OSTI]

of land use Part 1: Inventory modeling Roland Geyer & Davidthe use of GIS-based inventory modeling to generatedemonstrated that GIS-based inventory modeling of land use

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

2010-01-01T23:59:59.000Z

364

Bottom-up Representation of Industrial Energy Efficiency Technologies in Integrated Assessment Models for the Cement Sector  

SciTech Connect (OSTI)

Adoption of efficient end-use technologies is one of the key measures for reducing greenhouse gas (GHG) emissions. How to effectively analyze and manage the costs associated with GHG reductions becomes extremely important for the industry and policy makers around the world. Energy-climate (EC) models are often used for analyzing the costs of reducing GHG emissions for various emission-reduction measures, because an accurate estimation of these costs is critical for identifying and choosing optimal emission reduction measures, and for developing related policy options to accelerate market adoption and technology implementation. However, accuracies of assessing of GHG-emission reduction costs by taking into account the adoption of energy efficiency technologies will depend on how well these end-use technologies are represented in integrated assessment models (IAM) and other energy-climate models.

Sathaye, J.; Xu, T.; Galitsky, C.

2010-08-15T23:59:59.000Z

365

A validation of heat and carbon fluxes from highresolution land surface and regional models  

E-Print Network [OSTI]

) or regional climate models (RCMs) [Alessandri et al., 2007; Steiner et al., 2009]. [3., 2006; Alessandri et al., 2007; Jarlan et al., 2008; Steiner et al., 2009]. However, the SVAT models models do not account for the role of terrestrial vegetation in the carbon cycle variability [Alessandri

D'Andrea, Fabio

366

Science Highlight December 2010 Electrochemical Surface Science: Hard X-rays Probe Fuel Cell Model Catalyst  

E-Print Network [OSTI]

Science Highlight ­ December 2010 Electrochemical Surface Science: Hard X-rays Probe Fuel Cell. Proton exchange membrane fuel cells (PEMFCs) are promising power sources since they can generate distribution network. Large-scale deployment of fuel cells, however, has been hampered by cost and performance

Wechsler, Risa H.

367

Annals of Glaciology 52(59) 2011 99 Modeling surface-roughness/solar-ablation feedback  

E-Print Network [OSTI]

of Atmospheric, Oceanic and Space Sciences, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109 to small-scale surface channels and crevasses of the Greenland ice sheet L. Maclagan CATHLES,1 Dorian S. ABBOT,1 Jeremy N. BASSIS,2 Douglas R. MacAYEAL1 1 Department of Geophysical Sciences, University

Abbot, Dorian Schuyler

368

A model for the ultrasonic detection of surface-breaking cracks by the Scanning  

E-Print Network [OSTI]

). The generation of ultrasound by laser irradiation provides a number of advantages over the conventional of ultrasonic waves, use of fiber op- tics, narrow-band and broad-band generation, absolute measurements, surface ultrasonic waves can be detected using piezoelectric (PZT) or EMAT transducers, or optical

Huerta, Antonio

369

LOCAL UNIFIED MODELS OF BACKSCATTERING FROM OCEAN-LIKE SURFACES AT MODERATE INCIDENCE ANGLES  

E-Print Network [OSTI]

expanded up to the order two, like the SSA2 and LCA2. Electromagnetic scattering by rough surfaces, Random of the scattering matrix as SSA2, like the LCA2, were published by Elfouhaily et al. [10, 11]. It is well known is presented and tested for microwave frequencies and different wind speeds. The paper is organized as follows

Paris-Sud XI, Université de

370

Assessing the prospective environmental impacts of photovoltaic systems based on a simplified LCA model  

E-Print Network [OSTI]

Assessing the prospective environmental impacts of photovoltaic systems based on a simplified LCA the environmental impacts of PV systems are small during their operating phase, they are more significant during the use of LCA to assess the environmental impacts of one electricity-production technology. To address

Paris-Sud XI, Université de

371

Home composting as an alternative treatment option for organic household waste in Denmark: An environmental assessment using life cycle assessment-modelling  

SciTech Connect (OSTI)

An environmental assessment of the management of organic household waste (OHW) was performed from a life cycle perspective by means of the waste-life cycle assessment (LCA) model EASEWASTE. The focus was on home composting of OHW in Denmark and six different home composting units (with different input and different mixing frequencies) were modelled. In addition, incineration and landfilling was modelled as alternatives to home composting. The most important processes contributing to the environmental impact of home composting were identified as greenhouse gas (GHG) emissions (load) and the avoided emissions in relation to the substitution of fertiliser and peat when compost was used in hobby gardening (saving). The replacement of fertiliser and peat was also identified as one of the most sensible parameters, which could potentially have a significant environmental benefit. Many of the impact categories (especially human toxicity via water (HTw) and soil (HTs)) were affected by the heavy metal contents of the incoming OHW. The concentrations of heavy metals in the compost were below the threshold values for compost used on land and were thus not considered to constitute a problem. The GHG emissions were, on the other hand, dependent on the management of the composting units. The frequently mixed composting units had the highest GHG emissions. The environmental profiles of the home composting scenarios were in the order of -2 to 16 milli person equivalents (mPE) Mg{sup -1} wet waste (ww) for the non-toxic categories and -0.9 to 28 mPE Mg{sup -1} ww for the toxic categories. Home composting performed better than or as good as incineration and landfilling in several of the potential impact categories. One exception was the global warming (GW) category, in which incineration performed better due to the substitution of heat and electricity based on fossil fuels.

Andersen, J.K.; Boldrin, A.; Christensen, T.H. [Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kongens Lyngby (Denmark); Scheutz, C., E-mail: chas@env.dtu.dk [Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kongens Lyngby (Denmark)

2012-01-15T23:59:59.000Z

372

Mechanism of methanol synthesis on Cu(100) and Zn/Cu(100) surfaces: Comparative dipped adcluster model study  

SciTech Connect (OSTI)

The mechanism of methanol synthesis from CO{sub 2} and H{sub 2} on Cu(100) and Zn/Cu(100) surfaces was studied using the dipped adcluster model (DAM) combined with ab initio Hartree-Fock (HF) and second-order Moeller-Plesset (MP2) calculations. On clean Cu(100) surface, calculations show that five successive hydrogenations are involved in the hydrogenation of adsorbed CO{sub 2} to methanol, and the intermediates are formate, dioxomethylene, formaldehyde, and methoxy. The rate-limiting step is the hydrogenation of formate to formaldehyde, and the Cu-Cu site is responsible for the reaction on Cu(100). The roles of Zn on Zn/Cu(100) catalyst are to modify the rate-limiting step of the reaction: to lower the activation energies of this step and to stabilize the dioxomethylene intermediate at the Cu-Zn site. The present comparative results indicate that the Cu-Zn site is the active site, which cooperates with the Cu-Cu site to catalyze methanol synthesis on a Cu-based catalyst. Electron transfer from surface to adsorbates is the most important factor in affecting the reactivity of these surface catalysts.

Nakatsuji, Hiroshi; Hu, Zhenming

2000-03-05T23:59:59.000Z

373

Assessment of Uncertainties in the Response of the African Monsoon Precipitation to Land Use change simulated by a regional model  

SciTech Connect (OSTI)

Land use and land cover over Africa have changed substantially over the last sixty years and this change has been proposed to affect monsoon circulation and precipitation. This study examines the uncertainties on the effect of these changes on the African Monsoon system and Sahel precipitation using an ensemble of regional model simulations with different combinations of land surface and cumulus parameterization schemes. Although the magnitude of the response covers a broad range of values, most of the simulations show a decline in Sahel precipitation due to the expansion of pasture and croplands at the expense of trees and shrubs and an increase in surface air temperature.

Hagos, Samson M.; Leung, Lai-Yung R.; Xue, Yongkang; Boone, Aaron; de Sales, Fernando; Neupane, Naresh; Huang, Maoyi; Yoon, Jin-Ho

2014-02-22T23:59:59.000Z

374

The structure and properties of a simple model mixture of amphiphilic molecules and ions at a solid surface  

SciTech Connect (OSTI)

We investigate microscopic structure, adsorption, and electric properties of a mixture that consists of amphiphilic molecules and charged hard spheres in contact with uncharged or charged solid surfaces. The amphiphilic molecules are modeled as spheres composed of attractive and repulsive parts. The electrolyte component of the mixture is considered in the framework of the restricted primitive model (RPM). The system is studied using a density functional theory that combines fundamental measure theory for hard sphere mixtures, weighted density approach for inhomogeneous charged hard spheres, and a mean-field approximation to describe anisotropic interactions. Our principal focus is in exploring the effects brought by the presence of ions on the distribution of amphiphilic particles at the wall, as well as the effects of amphiphilic molecules on the electric double layer formed at solid surface. In particular, we have found that under certain thermodynamic conditions a long-range translational and orientational order can develop. The presence of amphiphiles produces changes of the shape of the differential capacitance from symmetric or non-symmetric bell-like to camel-like. Moreover, for some systems the value of the potential of the zero charge is non-zero, in contrast to the RPM at a charged surface.

Pizio, O., E-mail: pizio@unam.mx [Instituto de Química, Universidad Nacional Autonoma de México, Circuito Exterior, Ciudad Universitaria, 04510 México, D.F. (Mexico); Soko?owski, S., E-mail: stefan.sokolowski@gmail.com [Department for the Modeling of Physico-Chemical Processes, Maria Curie-Sk?odowska University, 20-031 Lublin (Poland); Soko?owska, Z. [Institute of Agrophysics, Polish Academy of Sciences, Do?wiadczalna 4, 20-290 Lublin (Poland)] [Institute of Agrophysics, Polish Academy of Sciences, Do?wiadczalna 4, 20-290 Lublin (Poland)

2014-05-07T23:59:59.000Z

375

Regional CO2 and latent heat surface fluxes in the Southern Great Plains: Measurements, modeling, and scaling  

SciTech Connect (OSTI)

Characterizing net ecosystem exchanges (NEE) of CO{sub 2} and sensible and latent heat fluxes in heterogeneous landscapes is difficult, yet critical given expected changes in climate and land use. We report here a measurement and modeling study designed to improve our understanding of surface to atmosphere gas exchanges under very heterogeneous land cover in the mostly agricultural U.S. Southern Great Plains (SGP). We combined three years of site-level, eddy covariance measurements in several of the dominant land cover types with regional-scale climate data from the distributed Mesonet stations and Next Generation Weather Radar precipitation measurements to calibrate a land surface model of trace gas and energy exchanges (isotope-enabled land surface model (ISOLSM)). Yearly variations in vegetation cover distributions were estimated from Moderate Resolution Imaging Spectroradiometer normalized difference vegetation index and compared to regional and subregional vegetation cover type estimates from the U.S. Department of Agriculture census. We first applied ISOLSM at a 250 m spatial scale to account for vegetation cover type and leaf area variations that occur on hundred meter scales. Because of computational constraints, we developed a subsampling scheme within 10 km 'macrocells' to perform these high-resolution simulations. We estimate that the Atmospheric Radiation Measurement Climate Research Facility SGP region net CO{sub 2} exchange with the local atmosphere was -240, -340, and -270 gC m{sup -2} yr{sup -1} (positive toward the atmosphere) in 2003, 2004, and 2005, respectively, with large seasonal variations. We also performed simulations using two scaling approaches at resolutions of 10, 30, 60, and 90 km. The scaling approach applied in current land surface models led to regional NEE biases of up to 50 and 20% in weekly and annual estimates, respectively. An important factor in causing these biases was the complex leaf area index (LAI) distribution within cover types. Biases in predicted weekly average regional latent heat fluxes were smaller than for NEE, but larger than for either ecosystem respiration or assimilation alone. However, spatial and diurnal variations of hundreds of W m{sup -2} in latent heat fluxes were common. We conclude that, in this heterogeneous system, characterizing vegetation cover type and LAI at the scale of spatial variation are necessary for accurate estimates of bottom-up, regional NEE and surface energy fluxes.

Riley, W. J.; Biraud, S.C.; Torn, M.S.; Fischer, M.L.; Billesbach, D.P.; Berry, J.A.

2009-08-15T23:59:59.000Z

376

Validity and sensitivity of a model for assessment of impacts of river floodplain reconstruction on protected and endangered species  

SciTech Connect (OSTI)

Environmental Impact Assessment (EIA) must account for legally protected and endangered species. Uncertainties relating to the validity and sensitivity of EIA arise from predictions and valuation of effects on these species. This paper presents a validity and sensitivity analysis of a model (BIO-SAFE) for assessment of impacts of land use changes and physical reconstruction measures on legally protected and endangered river species. The assessment is based on links between species (higher plants, birds, mammals, reptiles and amphibians, butterflies and dragon- and damselflies) and ecotopes (landscape ecological units, e.g., river dune, soft wood alluvial forests), and on value assignment to protected and endangered species using different valuation criteria (i.e., EU Habitats and Birds directive, Conventions of Bern and Bonn and Red Lists). The validity of BIO-SAFE has been tested by comparing predicted effects of landscape changes on the diversity of protected and endangered species with observed changes in biodiversity in five reconstructed floodplains. The sensitivity of BIO-SAFE to value assignment has been analysed using data of a Strategic Environmental Assessment concerning the Spatial Planning Key Decision for reconstruction of the Dutch floodplains of the river Rhine, aimed at flood defence and ecological rehabilitation. The weights given to the valuation criteria for protected and endangered species were varied and the effects on ranking of alternatives were quantified. A statistically significant correlation (p < 0.01) between predicted and observed values for protected and endangered species was found. The sensitivity of the model to value assignment proved to be low. Comparison of five realistic valuation options showed that different rankings of scenarios predominantly occur when valuation criteria are left out of the assessment. Based on these results we conclude that linking species to ecotopes can be used for adequate impact assessments. Quantification of sensitivity of impact assessment to value assignment shows that a model like BIO-SAFE is relatively insensitive to assignment of values to different policy and legislation based criteria. Arbitrariness of the value assignment therefore has a very limited effect on assessment outcomes. However, the decision to include valuation criteria or not is very important.

Nooij, R.J.W. de [Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands) and Netherlands Centre for River Studies (NCR), P.O. Box 177, 2600 MH Delft (Netherlands)]. E-mail: R.deNooij@science.ru.nl; Lotterman, K.M. [Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Sande, P.H.J. van de [Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Pelsma, T. [Institute for Inland Water Management and Waste Water Treatment (RIZA), P.O. Box 17, 8200 AA Lelystad (Netherlands); Netherlands Centre for River Studies (NCR), P.O. Box 177, 2600 MH Delft (Netherlands); Leuven, R.S.E.W. [Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Netherlands Centre for River Studies (NCR), P.O. Box 177, 2600 MH Delft (Netherlands); Lenders, H.J.R. [Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Netherlands Centre for River Studies (NCR), P.O. Box 177, 2600 MH Delft (Netherlands)

2006-11-15T23:59:59.000Z

377

A physical model of particulate wash-off from rough impervious surfaces  

E-Print Network [OSTI]

; accepted 23 January 2006 Summary Current urban water quality models rely on empirical, catchment of particulate available. Current urban stormwater models such as SWMM and HSPF are still based on this original urban storm runoff pollution. There are few published explanations of physical wash- off mechanisms

Walter, M.Todd

378

Developing an Integrated Model Framework for the Assessment of Sustainable Agricultural Residue Removal Limits for Bioenergy Systems  

SciTech Connect (OSTI)

Agricultural residues have significant potential as a feedstock for bioenergy production, but removing these residues can have negative impacts on soil health. Models and datasets that can support decisions about sustainable agricultural residue removal are available; however, no tools currently exist capable of simultaneously addressing all environmental factors that can limit availability of residue. The VE-Suite model integration framework has been used to couple a set of environmental process models to support agricultural residue removal decisions. The RUSLE2, WEPS, and Soil Conditioning Index models have been integrated. A disparate set of databases providing the soils, climate, and management practice data required to run these models have also been integrated. The integrated system has been demonstrated for two example cases. First, an assessment using high spatial fidelity crop yield data has been run for a single farm. This analysis shows the significant variance in sustainably accessible residue across a single farm and crop year. A second example is an aggregate assessment of agricultural residues available in the state of Iowa. This implementation of the integrated systems model demonstrates the capability to run a vast range of scenarios required to represent a large geographic region.

David Muth, Jr.; Jared Abodeely; Richard Nelson; Douglas McCorkle; Joshua Koch; Kenneth Bryden

2011-08-01T23:59:59.000Z

379

Modeling mining economics and materials markets to inform criticality assessment and mitigation  

E-Print Network [OSTI]

Conventional criticality-assessment methods drawn from the existing literature are often limited to evaluations of scarcity risks, or rely on price as an indicator of criticality. Such approaches, however, are ill-suited ...

Poulizac, Claire Marie Franc?oise

2013-01-01T23:59:59.000Z

380

Development and assessment of a soot emissions model for aircraft gas turbine engines  

E-Print Network [OSTI]

Assessing candidate policies designed to address the impact of aviation on the environment requires a simplified method to estimate pollutant emissions for current and future aircraft gas turbine engines under different ...

Martini, Bastien

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" 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

Assessment and preliminary model development of shape memory polymers mechanical counter pressure space suits  

E-Print Network [OSTI]

This thesis seeks to assess the viability of a space qualified shape memory polymer (SMP) mechanical counter pressure (MCP) suit. A key development objective identified by the International Space Exploration Coordination ...

Wee, Brian (Brian J.)

2013-01-01T23:59:59.000Z

382

Modifying the Soil and Water Assessment Tool to Simulate Cropland Carbon Flux: Model Development and Initial Evaluation  

SciTech Connect (OSTI)

Climate change is one of the most compelling modern issues and has important implications for almost every aspect of natural and human systems. The Soil and Water Assessment Tool (SWAT) model has been applied worldwide to support sustainable land and water management in a changing climate. However, the inadequacies of the existing carbon algorithm in SWAT limit its application in assessing impacts of human activities on CO2 emission, one important source of greenhouse gases (GHGs) that traps heat in the earth system and results in global warming. In this research, we incorporate a revised version of the CENTURY carbon model into SWAT to describe dynamics of soil organic matter (SOM)- residue and simulate land-atmosphere carbon exchange.

Zhang, Xuesong; Izaurralde, Roberto C.; Arnold, Jeffrey; Williams, Jimmy R.; Srinivasan, Raghavan

2013-10-01T23:59:59.000Z

383

Development of a Future Representative Concentration Pathway for Use in the IPCC 5th Assessment Earth System Model Simulations  

SciTech Connect (OSTI)

The representative concentration pathway to be delivered is a scenario of atmospheric concentrations of greenhouse gases and other radiatively important atmospheric species, along with land-use changes, derived from the Global Change Assessment Model (GCAM). The particular representative concentration pathway (RCP) that the Joint Global Change Research Institute (JGCRI) has been responsible for is a not-to-exceed pathway that stabilizes at a radiative forcing of 4.5Wm-2 in the year 2100.

None

2010-12-29T23:59:59.000Z

384

ASSESSMENT OF INTERACTION BETWEEN NORTH PACIFIC ALBACORE, THUNNUS ALALUNGA, FISHERIES BY USE OF A SIMULATION MODEL  

E-Print Network [OSTI]

OF A SIMULATION MODEL P. KLEIBER AND B. BAKER1 ABSTRACT Using a simulation model of a typical year in the North

385

Metabolic modeling for the deposition of transuranic nuclides on bone surfaces  

E-Print Network [OSTI]

The study of toxic effects of plutonium was begun by Dr. Glenn Seaborg in 1950 with a twenty year project. Although many effects of plutonium have been previously discovered during various studies, an accurate metabolic model for the transport...

Halter, Donald Anthony

1997-01-01T23:59:59.000Z

386

Incorporating and Evaluating Environmental Instream Flows in a Priority Order Based Surface Water Allocation Model  

E-Print Network [OSTI]

multi-objective optimization model to characterize the tradeoffs between water supply shortages and fish 10 population capacity in a stream on the west-slope of the Sierra Nevada mountain range. Harman and Stewardson (2005) evaluated a range...

Pauls, Mark

2014-03-18T23:59:59.000Z

387

NUMERICAL MODELING FOR THE FORMATION MECHANISM OF 3D TOPOGRAPHY ON MICROBIAL MAT SURFACES  

E-Print Network [OSTI]

though, that nutrient limitation coupled with fluid motion may play a key role as a physical control. Under this model, competitions of nutrients were setup among growing microbial communities, which later evolve into specially arranged, 3D mats. However...

Patel, Harsh Jay

2013-09-27T23:59:59.000Z

388

Paired chiral spin liquid with a Fermi surface in S=1 model on the triangular lattice  

E-Print Network [OSTI]

Motivated by recent experiments on Ba[subscript 3]NiSb[subscript 2]O[subscript 9], we investigate possible quantum spin liquid ground states for spin S=1 Heisenberg models on the triangular lattice. We use variational Monte ...

Bieri, Samuel

389

The potential use of Chernobyl fallout data to test and evaluate the predictions of environmental radiological assessment models  

SciTech Connect (OSTI)

The objectives of the Model Validation Committee were to collaborate with US and foreign scientists to collect, manage, and evaluate data for identifying critical research issues and data needs to support an integrated assessment of the Chernobyl nuclear accident; test environmental transport, human dosimetric, and health effects models against measured data to determine their efficacy in guiding decisions on protective actions and in estimating exposures to populations and individuals following a nuclear accident; and apply Chernobyl data to quantifications of key processes governing the environmental transport, fate and effects of radionuclides and other trace substances. 55 refs.

Richmond, C.R.; Hoffman, F.O.; Blaylock, B.G.; Eckerman, K.F.; Lesslie, P.A.; Miller, C.W.; Ng, Y.C.; Till, J.E.

1988-06-01T23:59:59.000Z

390

PHYSICAL REVIEW E 83, 026704 (2011) Atomistic modeling of metal surfaces under electric fields: Direct coupling of electric fields to a  

E-Print Network [OSTI]

at very high electric fields, as well as the general behavior of a metal surface in this conditionPHYSICAL REVIEW E 83, 026704 (2011) Atomistic modeling of metal surfaces under electric fields: Direct coupling of electric fields to a molecular dynamics algorithm F. Djurabekova,* S. Parviainen, A

Nordlund, Kai

2011-01-01T23:59:59.000Z

391

Coupling dry deposition to vegetation phenology in the Community Earth System Model: Implications for the simulation of surface O[subscript 3  

E-Print Network [OSTI]

Dry deposition is an important removal process controlling surface ozone. We examine the representation of this ozone loss mechanism in the Community Earth System Model. We first correct the dry deposition parameterization ...

Val?Martin, M.

392

Midtemperature solar systems test facility predictions for thermal performance based on test data. Polisolar Model POL solar collector with glass reflector surface  

SciTech Connect (OSTI)

Thermal performance predictions based on test data are presented for the Polisolar Model POL solar collector, with glass reflector surfaces, for three output temperatures at five cities in the United States.

Harrison, T.D.

1981-05-01T23:59:59.000Z

393

Assessment of Dissolved Oxygen Mitigation at Hydropower Dams Using an Integrated Hydrodynamic/Water Quality/Fish Growth Model  

SciTech Connect (OSTI)

Dissolved oxygen (DO) in rivers is a common environmental problem associated with hydropower projects. Approximately 40% of all FERC-licensed projects have requirements to monitor and/or mitigate downstream DO conditions. Most forms of mitigation for increasing DO in dam tailwaters are fairly expensive. One area of research of the Department of Energy's Hydropower Program is the development of advanced turbines that improve downstream water quality and have other environmental benefits. There is great interest in being able to predict the benefits of these modifications prior to committing to the cost of new equipment. In the case of turbine replacement or modification, there is a need for methods that allow us to accurately extrapolate the benefits derived from one or two turbines with better design to the replacement or modification of all turbines at a site. The main objective of our study was to demonstrate a modeling approach that integrates the effects of flow and water quality dynamics with fish bioenergetics to predict DO mitigation effectiveness over long river segments downstream of hydropower dams. We were particularly interested in demonstrating the incremental value of including a fish growth model as a measure of biological response. The models applied are a suite of tools (RMS4 modeling system) originally developed by the Tennessee Valley Authority for simulating hydrodynamics (ADYN model), water quality (RQUAL model), and fish growth (FISH model) as influenced by DO, temperature, and available food base. We parameterized a model for a 26-mile reach of the Caney Fork River (Tennessee) below Center Hill Dam to assess how improvements in DO at the dam discharge would affect water quality and fish growth throughout the river. We simulated different types of mitigation (i.e., at the turbine and in the reservoir forebay) and different levels of improvement. The model application successfully demonstrates how a modeling approach like this one can be used to assess whether a prescribed mitigation is likely to meet intended objectives from both a water quality and a biological resource perspective. These techniques can be used to assess the tradeoffs between hydropower operations, power generation, and environmental quality.

Bevelhimer, Mark S [ORNL; Coutant, Charles C [ORNL

2006-07-01T23:59:59.000Z

394

Evaluation of cloud fraction and its radiative effect simulated by IPCC AR4 global models against ARM surface observations  

SciTech Connect (OSTI)

Cloud Fraction (CF) is the dominant modulator of radiative fluxes. In this study, we evaluate CF simulations in the IPCC AR4 GCMs against ARM ground measurements, with a focus on the vertical structure, total amount of cloud and its effect on cloud shortwave transmissivity, for both inter-model deviation and model-measurement discrepancy. Our intercomparisons of three CF or sky-cover related dataset reveal that the relative differences are usually less than 10% (5%) for multi-year monthly (annual) mean values, while daily differences are quite significant. The results also show that the model-observation and the inter-model deviations have a similar magnitude for the total CF (TCF) and the normalized cloud effect, and they are twice as large as the surface downward solar radiation and cloud transmissivity. This implies that the other cloud properties, such as cloud optical depth and height, have a similar magnitude of disparity to TCF among the GCMs, and suggests that a better agreement among the GCMs in solar radiative fluxes could be the result of compensating errors in either cloud vertical structure, cloud optical depth or cloud fraction. Similar deviation pattern between inter-model and model-measurement suggests that the climate models tend to generate larger bias against observations for those variables with larger inter-model deviation. The simulated TCF from IPCC AR4 GCMs are very scattered through all seasons over three ARM sites: Southern Great Plains (SGP), Manus, Papua New Guinea and North Slope of Alaska (NSA). The GCMs perform better at SGP than at Manus and NSA in simulating the seasonal variation and probability distribution of TCF; however, the TCF in these models is remarkably underpredicted and cloud transmissivity is less susceptible to the change of TCF than the observed at SGP. Much larger inter-model deviation and model bias are found over NSA than the other sites in estimating the TCF, cloud transmissivity and cloud-radiation interaction, suggesting that the Arctic region continues to challenge cloud simulations in climate models. Most of the GCMs tend to underpredict CF and fail to capture the seasonal variation of CF at middle and low levels in the tropics. The high altitude CF is much larger in the GCMs than the observation and the inter-model variability of CF also reaches maximum at high levels in the tropics. Most of the GCMs tend to underpredict CF by 50-150% relative to the measurement average at low and middle levels over SGP. While the GCMs generally capture the maximum CF in the boundary layer and vertical variability, the inter-model deviation is largest near surface over the Arctic. The internal variability of CF simulated in ensemble runs with the same model is very minimal.

Qian, Yun; Long, Charles N.; Wang, Hailong; Comstock, Jennifer M.; McFarlane, Sally A.; Xie, Shaocheng

2012-02-17T23:59:59.000Z

395

Surface Complexation of Neptunium(V) onto Whole Cells and Cell Components of Shewanella alga: Modeling and Experimental Study  

SciTech Connect (OSTI)

We systematically quantified surface complexation of Np(V) onto whole cells, cell wall, and extracellular polymeric substances (EPS) of Shewanella alga strain BrY. We first performed acid and base titrations and used the mathematical model FITEQL to estimate the concentrations and deprotonation constants of specific surface functional groups. Deprotonation constants most likely corresponded to a carboxyl group not associated with amino acids (pK{sub a} {approx} 5), a phosphoryl site (pK{sub a} {approx} 7.2), and an amine site (pK{sub a} > 10). We then carried out batch sorption experiments with Np(V) and each of the S. alga components as a function of pH. Since significant Np(V) sorption was observed on S. alga whole cells and its components in the pH range 2-5, we assumed the existence of a fourth site: a low-pK{sub a} carboxyl site (pK{sub a} {approx} 2.4) that is associated with amino acids. We used the SPECIATE submodel of the biogeochemical model CCBATCH to compute the stability constants for Np(V) complexation to each surface functional group. The stability constants were similar for each functional group on S. alga bacterial whole cells, cell walls, and EPS, and they explain the complicated sorption patterns when they are combined with the aqueous-phase speciation of Np(V). For pH < 8, the aquo NpO{sub 2}{sup +} species was the dominant form of Np(V), and its log K values for the low-pK{sub a} carboxyl, mid-pK{sub a} carboxyl, and phosphoryl groups were 1.8, 1.8, and 2.5-3.1, respectively. For pH greater than 8, the key surface ligand was amine > XNH{sub 3}{sup +}, which complexed with NpO{sub 2}(CO{sub 3}){sub 3}{sup 5-}. The log K for NpO{sub 2}(CO{sub 3}){sub 3}{sup 5-} complexed onto the amine groups was 3.1-3.9. All of the log K values are similar to those of Np(V) complexes with aqueous carboxyl and N-containing carboxyl ligands. These results help quantify the role of surface complexation in defining actinide-microbiological interactions in the subsurface.

Deo, Randhir P.; Songkasiri, Warinthorn; Rittmann, Bruce E.; Reed, Donald T. (King Mongkut); (AZU); (LANL)

2012-04-30T23:59:59.000Z

396

Neptunium (V) Adsorption to a Halophilic Bacterium Under High Ionic Strength Conditions: A Surface Complexation Modeling Approach  

SciTech Connect (OSTI)

Rationale for experimental design: Np(V) -- important as analog for Pu(V) and for HLW scenarios; High ionic strength -- relevant to salt-based repositories such as the WIPP; Halophilic microorganisms -- representative of high ionic strength environments. For the first time showed: Significant adsorbant to halophilic microorganisms over entire pH range under high ionic strength conditions; Strong influence of ionic strength with increasing adsorption with increasing ionic strength (in contrast to trends of previous low ionic strength studies); Effect of aqueous Np(V) and bacterial surface site speciation on adsorption; and Developed thermodynamic models that can be incorporated into geochemical speciation models to aid in the prediction of the fate and transport of Np(V) in more complex systems.

Ams, David A [Los Alamos National Laboratory

2012-06-11T23:59:59.000Z

397

LONG-TERM GLOBAL WATER USE PROJECTIONS USING SIX SOCIOECONOMIC SCENARIOS IN AN INTEGRATED ASSESSMENT MODELING FRAMEWORK  

SciTech Connect (OSTI)

In this paper, we assess future water demands for the agricultural (irrigation and livestock), energy (electricity generation, primary energy production and processing), industrial (manufacturing and mining), and municipal sectors, by incorporating water demands into a technologically-detailed global integrated assessment model of energy, agriculture, and climate change – the Global Change Assessment Model (GCAM). Base-year water demands—both gross withdrawals and net consumptive use—are assigned to specific modeled activities in a way that maximizes consistency between bottom-up estimates of water demand intensities of specific technologies and practices, and top-down regional and sectoral estimates of water use. The energy, industrial, and municipal sectors are represented in fourteen geopolitical regions, with the agricultural sector further disaggregated into as many as eighteen agro-ecological zones (AEZs) within each region. We assess future water demands representing six socioeconomic scenarios, with no constraints imposed by future water supplies. The scenarios observe increases in global water withdrawals from 3,578 km3 year-1 in 2005 to 5,987 – 8,374 km3 year-1 in 2050, and to 4,719 – 12,290 km3 year-1 in 2095. Comparing the projected total regional water withdrawals to the historical supply of renewable freshwater, the Middle East exhibits the highest levels of water scarcity throughout the century, followed by India; water scarcity increases over time in both of these regions. In contrast, water scarcity improves in some regions with large base-year electric sector withdrawals, such as the USA and Canada, due to capital stock turnover and the almost complete phase-out of once-through flow cooling systems. The scenarios indicate that: 1) water is likely a limiting factor in climate change mitigation policies, 2) many regions can be expected to increase reliance on non-renewable groundwater, water reuse, and desalinated water, but they also highlight an important role for development and deployment of water conservation technologies and practices.

Hejazi, Mohamad I.; Edmonds, James A.; Clarke, Leon E.; Kyle, G. Page; Davies, Evan; Chaturvedi, Vaibhav; Wise, Marshall A.; Patel, Pralit L.; Eom, Jiyong; Calvin, Katherine V.; Moss, Richard H.; Kim, Son H.

2014-01-19T23:59:59.000Z

398

Modeling and experimental studies of oxide covered metal surfaces: TiO{sub 2}/Ti a model system. Progress report  

SciTech Connect (OSTI)

Prior work in our laboratories at the Corrosion Research Center has shown that thin, anodic TiO{sub 2} films formed by the Slow Growth Mode (SGM) on polycrystalline titanium and microcrystalline with a texture that varies from one metal grain to another. Furthermore, the underlying metal grains are mapped by the photoelectrochemical response of the oxide. The same characteristics have also been demonstrated in our laboratory for ZnO grown on Zn. The TiO{sub 2}/Ti system has been chosen for study both because of its importance in energy systems, and because it can serve as a model system for other metal-metal oxide couples. The investigations of anodic TiO{sub 2} films on Ti have shown that the properties of thin films are consistent with the rutile form of the oxide. Both experimental data and theoretical calculations show the close resemblance to results on single crystal TiO{sub 2}. Furthermore, the modeling studies reveal that the optical transitions near the bandedge arise from the bulk band structure. The photoelectrochemical properties of anodic TiO{sub 2} films have now been shown to obey the simple Gaertner-Butler model for the semiconductor-electrolyte interface, with a few modifications. The most important deviation has now been shown to be a result of multiple internal reflections in the oxide film.

Smyrl, W.H.

1991-12-31T23:59:59.000Z

399

Modeling and experimental studies of oxide covered metal surfaces: TiO sub 2 /Ti a model system  

SciTech Connect (OSTI)

Prior work in our laboratories at the Corrosion Research Center has shown that thin, anodic TiO{sub 2} films formed by the Slow Growth Mode (SGM) on polycrystalline titanium and microcrystalline with a texture that varies from one metal grain to another. Furthermore, the underlying metal grains are mapped by the photoelectrochemical response of the oxide. The same characteristics have also been demonstrated in our laboratory for ZnO grown on Zn. The TiO{sub 2}/Ti system has been chosen for study both because of its importance in energy systems, and because it can serve as a model system for other metal-metal oxide couples. The investigations of anodic TiO{sub 2} films on Ti have shown that the properties of thin films are consistent with the rutile form of the oxide. Both experimental data and theoretical calculations show the close resemblance to results on single crystal TiO{sub 2}. Furthermore, the modeling studies reveal that the optical transitions near the bandedge arise from the bulk band structure. The photoelectrochemical properties of anodic TiO{sub 2} films have now been shown to obey the simple Gaertner-Butler model for the semiconductor-electrolyte interface, with a few modifications. The most important deviation has now been shown to be a result of multiple internal reflections in the oxide film.

Smyrl, W.H.

1991-01-01T23:59:59.000Z

400

MODELING THE SURFACE X-RAY EMISSION AND VIEWING GEOMETRY OF PSR J0821-4300 IN PUPPIS A  

SciTech Connect (OSTI)

We present a model for the unusual X-ray pulse profiles of PSR J0821-4300, the compact central object in supernova remnant Puppis A. We show that a pair of thermal, antipodal hot spots on the neutron star (NS) surface is able to fully account for the pulsar's double blackbody spectrum and energy-dependent pulse profile, including the observed 180{sup 0} phase reversal at {approx}1.2 keV. By comparing the recorded pulse modulation and phase to the model predictions, we strongly constrain the hot-spot pole ({xi}) and the line-of-sight ({psi}) angles with respect to the spin axis. For a nominal radius of R = 12 km and distance D = 2.2 kpc, we find ({xi}, {psi}) = (86{sup 0}, 6{sup 0}), with 1{sigma} error ellipse of (2{sup 0}, 1{sup 0}); this solution is degenerate in the two angles. The best-fit spectral model for this geometry requires that the temperatures of the two emission spots differ by a factor of 2 and their areas by a factor of {approx}20. Including a cosine-beamed pattern for the emitted intensity modifies the result, decreasing the angles to (84{sup 0}, 3{sup 0}); however this model is not statistically distinguishable from the isotropic emission case. We also present a new upper limit on the period derivative of P-dot < 3.5x10{sup -16} (2{sigma}), which limits the global dipole magnetic field to B{sub s} < 2.0 x 10{sup 11} G, confirming PSR J0821-4300 as an 'anti-magnetar'. We discuss the results in the context of observations and theories of nonuniform surface temperature on isolated NSs of both weak and strong magnetic field. To explain the nonuniform temperature of PSR J0821-4300 may require a crustal field that is much stronger than the external, global dipole field.

Gotthelf, E. V.; Halpern, J. P. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Perna, R. [JILA and Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309 (United States)

2010-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" from the National Library of EnergyBeta (NLEBeta).
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401

Ecosystem feedbacks to climate change in California: Development, testing, and analysis using a coupled regional atmosphere and land-surface model (WRF3-CLM3.5)  

SciTech Connect (OSTI)

A regional atmosphere model [Weather Research and Forecasting model version 3 (WRF3)] and a land surface model [Community Land Model, version 3.5 (CLM3.5)] were coupled to study the interactions between the atmosphere and possible future California land-cover changes. The impact was evaluated on California's climate of changes in natural vegetation under climate change and of intentional afforestation. The ability of WRF3 to simulate California's climate was assessed by comparing simulations by WRF3-CLM3.5 and WRF3-Noah to observations from 1982 to 1991. Using WRF3-CLM3.5, the authors performed six 13-yr experiments using historical and future large-scale climate boundary conditions from the Geophysical Fluid Dynamics Laboratory Climate Model version 2.1 (GFDL CM2.1). The land-cover scenarios included historical and future natural vegetation from the Mapped Atmosphere-Plant-Soil System-Century 1 (MC1) dynamic vegetation model, in addition to a future 8-million-ha California afforestation scenario. Natural vegetation changes alone caused summer daily-mean 2-m air temperature changes of -0.7 to +1 C in regions without persistent snow cover, depending on the location and the type of vegetation change. Vegetation temperature changes were much larger than the 2-m air temperature changes because of the finescale spatial heterogeneity of the imposed vegetation change. Up to 30% of the magnitude of the summer daily-mean 2-m air temperature increase and 70% of the magnitude of the 1600 local time (LT) vegetation temperature increase projected under future climate change were attributable to the climate-driven shift in land cover. The authors projected that afforestation could cause local 0.2-1.2 C reductions in summer daily-mean 2-m air temperature and 2.0-3.7 C reductions in 1600 LT vegetation temperature for snow-free regions, primarily because of increased evapotranspiration. Because some of these temperature changes are of comparable magnitude to those projected under climate change this century, projections of climate and vegetation change in this region need to consider these climate-vegetation interactions.

Subin, Z.M.; Riley, W.J.; Kueppers, L.M.; Jin, J.; Christianson, D.S.; Torn, M.S.

2010-11-01T23:59:59.000Z

402

DRAFT6-08Sept02 page 1 Simulation of Progressive Cutting on Surface Mesh Model  

E-Print Network [OSTI]

Payandeh and John Dill Robotics and Computer Graphics Laboratories, School of Engineering Science Simon simulation is a promising technology for training medical students and surgery planning. An important models must be based on physical laws governing the dynamic behavior of rigid and deformable objects

403

Users guide for the hydroacoustic coverage assessment model (HydroCAM)  

SciTech Connect (OSTI)

A model for predicting the detection and localization performance of hydroacoustic monitoring networks has been developed. The model accounts for major factors affecting global-scale acoustic propagation in the ocean. including horizontal refraction, travel time variability due to spatial and temporal fluctuations in the ocean, and detailed characteristics of the source. Graphical user interfaces are provided to setup the models and visualize the results. The model produces maps of network detection coverage and localization area of uncertainty, as well as intermediate results such as predicted path amplitudes, travel time and travel time variance. This Users Guide for the model is organized into three sections. First a summary of functionality available in the model is presented, including example output products. The second section provides detailed descriptions of each of models contained in the system. The last section describes how to run the model, including a summary of each data input form in the user interface.

Farrell, T., LLNL

1997-12-01T23:59:59.000Z

404

Assessing the performance of thermospheric modelling with data assimilation throughout solar cycles 23 and 24  

E-Print Network [OSTI]

Data assimilation procedures have been developed for thermospheric models using satellite density measurements as part of the EU Framework Package 7 ATMOP Project. Two models were studied; one a general circulation model, TIEGCM, and the other a semi-empirical drag temperature model, DTM. Results of runs using data assimilation with these models were compared with independent density observations from CHAMP and GRACE satellites throughout solar cycles 23 and 24. Time periods of 60 days were examined at solar minimum and maximum, including the 2003 Hallowe'en storms. The differences between the physical and the semi-empirical models have been characterised. Results indicate that both models tend to show similar behaviour; underestimating densities at solar maximum, and overestimating them at solar minimum. DTM performed better at solar minimum, with both models less accurate at solar maximum. A mean improvement of ~4% was found using data assimilation with TIEGCM. With further improvements, the use of general ...

Murray, Sophie A; Jackson, David R; Bruinsma, Sean L

2015-01-01T23:59:59.000Z

405

ESD.864 / ESD.936 Systems Modeling and Assessment for Policy, Spring 2010  

E-Print Network [OSTI]

This course explores how scientific information can be used to inform policy decision-making processes through the use of quantitative modeling techniques. It incorporates both hands-on analysis and practice using models ...

Selin, Noelle

406

Ensemble operational air quality assessments in Europe Improving modeling platforms with statistical analysis  

E-Print Network [OSTI]

with statistical analysis Anthony Ung, Laure Malherbe, Frederik Meleux, Bertrand Bessagnet, Laurence Rouil and MACCII modeling team INERIS institut, Paris, France Corresponding author: Anthony.ung@ineris.fr Abstract/QC dossiers and available on the MACC project website for each model. All models have also very significant

Paris-Sud XI, Université de

407

The surface carbon and nitrogen abundances in models of ultra metal-poor stars  

E-Print Network [OSTI]

We investigate whether the observed high number of carbon- and nitrogen-enhanced extremely metal-poor stars could be explained by peculiar evolutionary properties during the core He flash at the tip of the red giant branch. For this purpose we compute a series of detailed stellar models expanding upon our previous work; in particular, we investigate if during the major He flash the penetration of the helium convective zone into the overlying hydrogen-rich layers can produce carbon- and nitrogen-rich abundances in agreement with current spectroscopic observations. The dependence of this phenomenon on selected model input parameters, such as initial metallicity and treatment of convection is examined in detail.

H. Schlattl; M. Salaris; S. Cassisi; A. Weiss

2002-05-20T23:59:59.000Z

408

Comparison of surface meteorological data representativeness for the Weldon Spring transport and dispersion modeling analysis  

SciTech Connect (OSTI)

The US Department of Energy is conducting the Weldon Spring Site Remedial Action Project under the Surplus Facilities Management Program (SFMP). The major goals of the SFMP are to eliminate potential hazards to the public and the environment that associated with contamination at SFMP sites and to make surplus property available for other uses to the extent possible. This report presents the results of analysis of available meteorological data from stations near the Weldon Spring site. Data that are most representative of site conditions are needed to accurately model the transport and dispersion of air pollutants associated with remedial activities. Such modeling will assist the development of mitigative measures. 17 refs., 12 figs., 6 tabs.

Lazaro, M.

1989-06-01T23:59:59.000Z

409

A model of the near-surface seismic velocity: southern San Joaqin Valley, California  

E-Print Network [OSTI]

, representative hydrograph for the central valley Figure 1. (a. ) Sea-level correctional velocity the from preliminary study estimated for the 1980's. Page 3 3 3. Preliminary test data plotted for the model of constant velocity above and below the water... variations, a major problem is to determine the static corrections for seismic data which were surveyed during the last 20 years. Because of the limited number of traveltime measurements, it would be desirable to use all ot the measurements which were...

Ferry, James Gerard

2012-06-07T23:59:59.000Z

410

Modeling  

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

411

E-Print Network 3.0 - assessment part ii Sample Search Results  

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

Assessment Model The TENCompetence Assessment Model... , 60 2009 Sofia Service Oriented Architecture of Assessment Model1 Adelina Aleksieva... Assessment Model. To achieve...

412

numerical models & information Systems, Nice: France (2013)" Environmental impact for offshore wind farms: Geolocalized Life Cycle Assessment (LCA) approach  

E-Print Network [OSTI]

Abstract. This paper presents an approach for Environmental Impact Assessment through the use of geolocalized LCA approach, for fixed and floating offshore wind farms. This work was undertaken within the EUsponsored EnerGEO project, aiming at providing a versatile modeling platform for stakeholders allowing calculation, forecasting and monitoring of environmental impacts of different sources of energy. This paper described the geolocalized LCA approach, and its use for the evaluation of environmental impacts of wind energy. The effects of offshore wind farms on global environnemental impacts are evaluated though the LCA approach. It takes into account the type of wind farm, the construction phase, all technical aspects, the operation and maintenance scheme and the decommissioning. It also includes geolocalized information such as wind resources, bathymetry, accessibility … Environmental impact parameters are accessible through a web service helping the decision makers in assessing the environnemental impacts. 1

Catherine Guermont; Lionel Ménard; Isabelle Blanc

2013-01-01T23:59:59.000Z

413

Development of Surface Complexation Models of Cr(VI) Adsorption on Soils, Sediments and Model Mixtures of Kaolinite, Montmorillonite, ?-Alumina, Hydrous Manganese and Ferric Oxides and Goethite  

SciTech Connect (OSTI)

Hexavalent chromium is a highly toxic contaminant that has been introduced into aquifers and shallow sediments and soils via many anthropogenic activities. Hexavalent chromium contamination is a problem or potential problem in the shallow subsurface at several DOE sites, including Hanford, Idaho National Laboratory, Los Alamos National Laboratory and the Oak Ridge Reservation (DOE, 2008). To accurately quantify the fate and transport of hexavalent chromium at DOE and other contaminated sites, robust geochemical models, capable of correctly predicting changes in chromium chemical form resulting from chemical reactions occurring in subsurface environments are needed. One important chemical reaction that may greatly impact the bioavailability and mobility of hexavalent chromium in the subsurface is chemical binding to the surfaces of particulates, termed adsorption or surface complexation. Quantitative thermodynamic surface complexation models have been derived that can correctly calculate hexavalent chromium adsorption on well-characterized materials over ranges in subsurface conditions, such pH and salinity. However, models have not yet been developed for hexavalent chromium adsorption on many important constituents of natural soils and sediments, such as clay minerals. Furthermore, most of the existing thermodynamic models have been developed for relatively simple, single solid systems and have rarely been tested for the complex mixtures of solids present in real sediments and soils. In this study, the adsorption of hexavalent chromium was measured as a function of pH (3-10), salinity (0.001 to 0.1 M NaNO3), and partial pressure of carbon dioxide(0-5%) on a suite of naturally-occurring solids including goethite (FeOOH), hydrous manganese oxide (MnOOH), hydrous ferric oxide (Fe(OH)3), ?-alumina (Al2O3), kaolinite (Al2Si2O5(OH)4), and montmorillonite (Na3(Al, Mg)2Si4O10(OH)2?nH2O). The results show that all of these materials can bind substantial quantities of hexavalent chromium, especially at low pH. Unexpectedly, experiments with the clay minerals kaolinite and montmorillonite suggest that hexavalent chromium may interact with these solids over much longer periods of time than expected. Furthermore, hexavalent chromium may irreversibly bind to these solids, perhaps because of oxidation-reduction reactions occurring on the surfaces of the clay minerals. More work should be done to investigate and quantify these chemical reactions. Experiments conducted with mixtures of goethite, hydrous manganese oxide, hydrous ferric oxide, ?-alumina, montmorillonite and kaolinite demonstrate that it is possible to correctly predict hexavalent chromium binding in the presence of multiple minerals using thermodynamic models derived for the simpler systems. Further, these models suggest that of the six solid considered in this study, goethite is typically the solid to which most of the hexavalent chromium will bind. Experiments completed with organic-rich and organic-poor natural sediments demonstrate that in organic-rich substrates, organic matter is likely to control uptake of the hexavalent chromium. The models derived and tested in this study for hexavalent chromium binding to ?-alumina, hydrous manganese oxide, goethite, hydrous ferric oxide and clay minerals can be used to better predict changes in hexavalent chromium bioavailability and mobility in contaminated sediments and soils.

Koretsky, Carla [Western Michigan University] [Western Michigan University

2013-11-29T23:59:59.000Z

414

Recent Approaches to Modeling Transport of Mercury in Surface Water and Groundwater - Case Study in Upper East Fork Poplar Creek, Oak Ridge, TN - 13349  

SciTech Connect (OSTI)

In this case study, groundwater/surface water modeling was used to determine efficacy of stabilization in place with hydrologic isolation for remediation of mercury contaminated areas in the Upper East Fork Poplar Creek (UEFPC) Watershed in Oak Ridge, TN. The modeling simulates the potential for mercury in soil to contaminate groundwater above industrial use risk standards and to contribute to surface water contamination. The modeling approach is unique in that it couples watershed hydrology with the total mercury transport and provides a tool for analysis of changes in mercury load related to daily precipitation, evaporation, and runoff from storms. The model also allows for simulation of colloidal transport of total mercury in surface water. Previous models for the watershed only simulated average yearly conditions and dissolved concentrations that are not sufficient for predicting mercury flux under variable flow conditions that control colloidal transport of mercury in the watershed. The transport of mercury from groundwater to surface water from mercury sources identified from information in the Oak Ridge Environmental Information System was simulated using a watershed scale model calibrated to match observed daily creek flow, total suspended solids and mercury fluxes. Mercury sources at the former Building 81-10 area, where mercury was previously retorted, were modeled using a telescopic refined mesh with boundary conditions extracted from the watershed model. Modeling on a watershed scale indicated that only source excavation for soils/sediment in the vicinity of UEFPC had any effect on mercury flux in surface water. The simulations showed that colloidal transport contributed 85 percent of the total mercury flux leaving the UEFPC watershed under high flow conditions. Simulation of dissolved mercury transport from liquid elemental mercury and adsorbed sources in soil at former Building 81-10 indicated that dissolved concentrations are orders of magnitude below a target industrial groundwater concentration beneath the source and would not influence concentrations in surface water at Station 17. This analysis addressed only shallow concentrations in soil and the shallow groundwater flow path in soil and unconsolidated sediments to UEFPC. Other mercury sources may occur in bedrock and transport though bedrock to UEFPC may contribute to the mercury flux at Station 17. Generally mercury in the source areas adjacent to the stream and in sediment that is eroding can contribute to the flux of mercury in surface water. Because colloidally adsorbed mercury can be transported in surface water, actions that trap colloids and or hydrologically isolate surface water runoff from source areas would reduce the flux of mercury in surface water. Mercury in soil is highly adsorbed and transport in the groundwater system is very limited under porous media conditions. (authors)

Bostick, Kent; Daniel, Anamary [Professional Project Services, Inc., Bethel Valley Road, Oak Ridge, TN, 37922 (United States)] [Professional Project Services, Inc., Bethel Valley Road, Oak Ridge, TN, 37922 (United States); Tachiev, Georgio [Florida International University, Applied Research Center 10555 W. Flagler St., EC 2100 Miami Florida 33174 (United States)] [Florida International University, Applied Research Center 10555 W. Flagler St., EC 2100 Miami Florida 33174 (United States); Malek-Mohammadi, Siamak [Bradley University, 413A Jobst Hall, Preoria, IL 61625 (United States)] [Bradley University, 413A Jobst Hall, Preoria, IL 61625 (United States)

2013-07-01T23:59:59.000Z

415

E-Print Network 3.0 - analytical model assessing Sample Search...  

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

systems with ceramic membranes 12;SAW - HydrogenRelatedAnalytical... , and modeling of gasification and petroleum refining ... Source: DOE Office of Energy Efficiency and...

416

MA3T Model Application at ORNL Assesses the Future of Fuel Cell...  

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

has developed a model for simulating the market potential of fuel cell electric vehicles (FCEV) and challenges to achieving success over time, including competition with...

417

Seismic Performance, Modeling, and Failure Assessment of Reinforced Concrete Shear Wall Buildings  

E-Print Network [OSTI]

J.W. , (2009). Testing and Reinforced Concrete Coupling2010). "Testing and Modeling of Reinforced Concrete Couplingscale testing of four-story reinforced concrete and post-

Tuna, Zeynep

2012-01-01T23:59:59.000Z

418

What is the importance of climate model bias when projecting the impacts of climate change on land surface processes?  

SciTech Connect (OSTI)

Regional climate change impact (CCI) studies have widely involved downscaling and bias-correcting (BC) Global Climate Model (GCM)-projected climate for driving land surface models. However, BC may cause uncertainties in projecting hydrologic and biogeochemical responses to future climate due to the impaired spatiotemporal covariance of climate variables and a breakdown of physical conservation principles. Here we quantify the impact of BC on simulated climate-driven changes in water variables(evapotranspiration, ET; runoff; snow water equivalent, SWE; and water demand for irrigation), crop yield, biogenic volatile organic compounds (BVOC), nitric oxide (NO) emissions, and dissolved inorganic nitrogen (DIN) export over the Pacific Northwest (PNW) Region. We also quantify the impacts on net primary production (NPP) over a small watershed in the region (HJ Andrews). Simulation results from the coupled ECHAM5/MPI-OM model with A1B emission scenario were firstly dynamically downscaled to 12 km resolutions with WRF model. Then a quantile mapping based statistical downscaling model was used to downscale them into 1/16th degree resolution daily climate data over historical and future periods. Two series climate data were generated according to the option of bias-correction (i.e. with bias-correction (BC) and without bias-correction, NBC). Impact models were then applied to estimate hydrologic and biogeochemical responses to both BC and NBC meteorological datasets. These im20 pact models include a macro-scale hydrologic model (VIC), a coupled cropping system model (VIC-CropSyst), an ecohydrologic model (RHESSys), a biogenic emissions model (MEGAN), and a nutrient export model (Global-NEWS). Results demonstrate that the BC and NBC climate data provide consistent estimates of the climate-driven changes in water fluxes (ET, runoff, and water demand), VOCs (isoprene and monoterpenes) and NO emissions, mean crop yield, and river DIN export over the PNW domain. However, significant differences rise from projected SWE, crop yield from dry lands, and HJ Andrews’s ET between BC and NBC data. Even though BC post-processing has no significant impacts on most of the studied variables when taking PNW as a whole, their effects have large spatial variations and some local areas are substantially influenced. In addition, there are months during which BC and NBC post-processing produces significant differences in projected changes, such as summer runoff. Factor-controlled simulations indicate that BC post-processing of precipitation and temperature both substantially contribute to these differences at region scales. We conclude that there are trade-offs between using BC climate data for offline CCI studies vs. direct modeled climate data. These trade-offs should be considered when designing integrated modeling frameworks for specific applications; e.g., BC may be more important when considering impacts on reservoir operations in mountainous watersheds than when investigating impacts on biogenic emissions and air quality (where VOCs are a primary indicator).

Liu, M. L.; Rajagopalan, K.; Chung, S. H.; Jiang, X.; Harrison, J. H.; Nergui, T.; Guenther, Alex B.; Miller, C.; Reyes, J.; Tague, C. L.; Choate, J. S.; Salathe, E.; Stockle, Claudio O.; Adam, J. C.

2014-05-16T23:59:59.000Z

419

Multi-dimensional modelling of electrostatic force distance curve over dielectric surface: Influence of tip geometry and correlation with experiment  

SciTech Connect (OSTI)

Electric Force-Distance Curves (EFDC) is one of the ways whereby electrical charges trapped at the surface of dielectric materials can be probed. To reach a quantitative analysis of stored charge quantities, measurements using an Atomic Force Microscope (AFM) must go with an appropriate simulation of electrostatic forces at play in the method. This is the objective of this work, where simulation results for the electrostatic force between an AFM sensor and the dielectric surface are presented for different bias voltages on the tip. The aim is to analyse force-distance curves modification induced by electrostatic charges. The sensor is composed by a cantilever supporting a pyramidal tip terminated by a spherical apex. The contribution to force from cantilever is neglected here. A model of force curve has been developed using the Finite Volume Method. The scheme is based on the Polynomial Reconstruction Operator—PRO-scheme. First results of the computation of electrostatic force for different tip–sample distances (from 0 to 600?nm) and for different DC voltages applied to the tip (6 to 20?V) are shown and compared with experimental data in order to validate our approach.

Boularas, A., E-mail: boularas@laplace.univ-tlse.fr; Baudoin, F.; Villeneuve-Faure, C. [LAPLACE (Laboratoire Plasma et Conversion d'Energie), Université de Toulouse, UPS, INPT, 118 route de Narbonne, 31062 Toulouse cedex 9 (France); Clain, S. [Universidade do Minho, Centro de Matemática, Campus de Gualtar, 4710 - 057 Braga (Portugal); Université Paul Sabatier, Institut de Mathématiques de Toulouse, 31062 Toulouse (France); Teyssedre, G. [LAPLACE (Laboratoire Plasma et Conversion d'Energie), Université de Toulouse, UPS, INPT, 118 route de Narbonne, 31062 Toulouse cedex 9 (France); CNRS, LAPLACE, F-31071 Toulouse (France)

2014-08-28T23:59:59.000Z

420

An Assessment of Interval Data and Their Potential Application to Residential Electricity End-Use Modeling  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"Click worksheet9,1,50022,3,,,,6,1,,781Title: Telephone:short version)ecTotalnerrSpring:7)An Assessment

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421

Spent nuclear fuel as a waste form for geologic disposal: Assessment and recommendations on data and modeling needs  

SciTech Connect (OSTI)

This study assesses the status of knowledge pertinent to evaluating the behavior of spent nuclear fuel as a waste form in geologic disposal systems and provides background information that can be used by the DOE to address the information needs that pertain to compliance with applicable standards and regulations. To achieve this objective, applicable federal regulations were reviewed, expected disposal environments were described, the status of spent-fuel modeling was summarized, and information regarding the characteristics and behavior of spent fuel was compiled. This compiled information was then evaluated from a performance modeling perspective to identify further information needs. A number of recommendations were made concerning information still needed to enhance understanding of spent-fuel behavior as a waste form in geologic repositories. 335 refs., 22 figs., 44 tabs.

Van Luik, A.E.; Apted, M.J.; Bailey, W.J.; Haberman, J.H.; Shade, J.S.; Guenther, R.E.; Serne, R.J.; Gilbert, E.R.; Peters, R.; Williford, R.E.

1987-09-01T23:59:59.000Z

422

A new analytic-adaptive model for EGS assessment, development and management support  

Broader source: Energy.gov [DOE]

This project will develop an in depth model of EGS systems that will allow engineers, practitioners, and researchers to more accurately predict how new fluid technologies would work in a reservoir.

423

Climate Change Impacts for Conterminous USA: An Integrated Assessment Part 2. Models and Validation  

SciTech Connect (OSTI)

As CO{sub 2} and other greenhouse gases accumulate in the atmosphere and contribute to rising global temperatures, it is important to examine how a changing climate may affect natural and managed ecosystems. In this series of papers, we study the impacts of climate change on agriculture, water resources and natural ecosystems in the conterminous United States using a suite of climate change predictions from General Circulation Models (GCMs) as described in Part 1. Here we describe the agriculture model EPIC and the HUMUS water model and validate them with historical crop yields and streamflow data. We compare EPIC simulated grain and forage crop yields with historical crop yields from the US Department of Agriculture and find an acceptable level of agreement for this study. The validation of HUMUS simulated streamflow with estimates of natural streamflow from the US Geological Survey shows that the model is able to reproduce significant relationships and capture major trends.

Thomson, Allison M.; Rosenberg, Norman J.; Izaurralde, R Cesar C.; Brown, Robert A.

2005-03-01T23:59:59.000Z

424

Advanced Technologies in Energy-Economy Models for Climate Change Assessment  

E-Print Network [OSTI]

Considerations regarding the roles of advanced technologies are crucial in energy-economic modeling, as these technologies, while usually not yet commercially viable, could substitute for fossil energy when relevant policies ...

Morris, J.F.

425

Assessing Invariance of Factor Structures and Polytomous Item Response Model Parameter Estimates  

E-Print Network [OSTI]

.e., identical items, different people) for the homogenous graded response model (Samejima, 1969) and the partial credit model (Masters, 1982)? To evaluate measurement invariance using IRT methods, the item discrimination and item difficulty parameters... obtained from the GRM need to be equivalent across datasets. The YFCY02 and YFCY03 GRM item discrimination parameters (slope) correlation was 0.828. The YFCY02 and YFCY03 GRM item difficulty parameters (location) correlation was 0...

Reyes, Jennifer McGee

2012-02-14T23:59:59.000Z

426

Seminar on Radioactive Waste, Modelling and Dose Assessment -Ris National Laboratory 2 -6 December 2002 Assessment of doses and environmental contamination  

E-Print Network [OSTI]

December 2002 Assessment of doses and environmental contamination from decommissioning of the nuclear on the environment dur- ing the decommissioning of the nuclear facilities at Risø and the assessed consequences facilities at Risø Per Hedemann Jensen Section of Applied Health Physics Risø Department of Decommissioning

427

Assessment of One- and Two-Equation Turbulence Models for Hypersonic Transitional Flows  

SciTech Connect (OSTI)

Many Navier-Stokes codes require that the governing equations be written in conservation form with a source term. The Spalart-Allmaras one-equation model was originally developed in substantial derivative form and when rewritten in conservation form, a density gradient term appears in the source term. This density gradient term causes numerical problems and has a small influence on the numerical predictions. Further work has been performed to understand and to justify the neglect of this term. The transition trip term has been included in the one-equation eddy viscosity model of Spalart-Allmaras. Several problems with this model have been discovered when applied to high-speed flows. For the Mach 8 flat plate boundary layer flow with the standard transition method, the Baldwin-Barth and both k-{omega} models gave transition at the specified location. The Spalart-Allmaras and low Reynolds number k-{var_epsilon} models required an increase in the freestream turbulence levels in order to give transition at the desired location. All models predicted the correct skin friction levels in both the laminar and turbulent flow regions. For Mach 8 flat plate case, the transition location could not be controlled with the trip terms as given in the Spalart-Allmaras model. Several other approaches have been investigated to allow the specification of the transition location. The approach that appears most appropriate is to vary the coefficient that multiplies the turbulent production term in the governing partial differential equation for the eddy viscosity (Method 2). When this coefficient is zero, the flow remains laminar. The coefficient is increased to its normal value over a specified distance to crudely model the transition region and obtain fully turbulent flow. While this approach provides a reasonable interim solution, a separate effort should be initiated to address the proper transition procedure associated with the turbulent production term. Also, the transition process might be better modeled with the Spalart-Allmaras turbulence model with modification of the damping function f{sub v1}. The damping function could be set to zero in the laminar flow region and then turned on through the transition flow region.

ROY,CHRISTOPHER J.; BLOTTNER,FREDERICK G.

2000-01-14T23:59:59.000Z

428

Model Developments for Development of Improved Emissions Scenarios: Developing Purchasing-Power Parity Models, Analyzing Uncertainty, and Developing Data Sets for Gridded Integrated Assessment Models  

SciTech Connect (OSTI)

In the duration of this project, we finished the main tasks set up in the initial proposal. These tasks include: setting up the basic platform in GAMS language for the new RICE 2007 model; testing various model structure of RICE 2007; incorporating PPP data set in the new RICE model; developing gridded data set for IA modeling.

Yang, Zili; Nordhaus, William

2009-03-19T23:59:59.000Z

429

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

SciTech Connect (OSTI)

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

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

2006-12-21T23:59:59.000Z

430

VOLUME 87, NUMBER 4 P H Y S I C A L R E V I E W L E T T E R S 23 JULY 2001 Critical Coarsening without Surface Tension: The Universality Class of the Voter Model  

E-Print Network [OSTI]

without Surface Tension: The Universality Class of the Voter Model Ivan Dornic,1 Hugues Chaté,2 Jérôme competition is driven by surface tension, leading to "curvature-driven" growth. Coarsening patterns of models for which phase ordering takes place without surface ten- sion. We argue that voter-like growth

Chave, Jérôme

431

A novel QSAR model of Salmonella mutagenicity and its application in the safety assessment of drug impurities  

SciTech Connect (OSTI)

As indicated in ICH M7 draft guidance, in silico predictive tools including statistically-based QSARs and expert analysis may be used as a computational assessment for bacterial mutagenicity for the qualification of impurities in pharmaceuticals. To address this need, we developed and validated a QSAR model to predict Salmonella t. mutagenicity (Ames assay outcome) of pharmaceutical impurities using Prous Institute's Symmetry?, a new in silico solution for drug discovery and toxicity screening, and the Mold2 molecular descriptor package (FDA/NCTR). Data was sourced from public benchmark databases with known Ames assay mutagenicity outcomes for 7300 chemicals (57% mutagens). Of these data, 90% was used to train the model and the remaining 10% was set aside as a holdout set for validation. The model's applicability to drug impurities was tested using a FDA/CDER database of 951 structures, of which 94% were found within the model's applicability domain. The predictive performance of the model is acceptable for supporting regulatory decision-making with 84 ± 1% sensitivity, 81 ± 1% specificity, 83 ± 1% concordance and 79 ± 1% negative predictivity based on internal cross-validation, while the holdout dataset yielded 83% sensitivity, 77% specificity, 80% concordance and 78% negative predictivity. Given the importance of having confidence in negative predictions, an additional external validation of the model was also carried out, using marketed drugs known to be Ames-negative, and obtained 98% coverage and 81% specificity. Additionally, Ames mutagenicity data from FDA/CFSAN was used to create another data set of 1535 chemicals for external validation of the model, yielding 98% coverage, 73% sensitivity, 86% specificity, 81% concordance and 84% negative predictivity. - Highlights: • A new in silico QSAR model to predict Ames mutagenicity is described. • The model is extensively validated with chemicals from the FDA and the public domain. • Validation tests show desirable high sensitivity and high negative predictivity. • The model predicted 14 reportedly difficult to predict drug impurities with accuracy. • The model is suitable to support risk evaluation of potentially mutagenic compounds.

Valencia, Antoni; Prous, Josep; Mora, Oscar [Prous Institute for Biomedical Research, Rambla de Catalunya, 135, 3-2, Barcelona 08008 (Spain); Sadrieh, Nakissa [Office of Pharmaceutical Science, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993-0002 (United States); Valerio, Luis G., E-mail: luis.valerio@fda.hhs.gov [Office of Pharmaceutical Science, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993-0002 (United States)

2013-12-15T23:59:59.000Z

432

Application of probabilistic safety assessment models to risk-based inspection of piping  

SciTech Connect (OSTI)

From the beginning, one of the most useful applications of Probabilistic Safety Assessment (PSA) is its use in evaluating the risk importance of changes to plant design, operations, or other plant conditions. Risk importance measures the impact of a change on the risk. Risk is defined as a combination of the likelihood of failure and consequence of the failure. The consequence can be safety system unavailability, core melt frequency, early release, or various other consequence measures. The goal in this PSA application is to evaluate the risk importance of an ISI process, as applied to plant piping systems. Two approaches can be taken in this evaluation: Current PSA Approach or the Blended Approach. Both are discussed here.

Chapman, J.

1996-12-01T23:59:59.000Z

433

Overview of technology modeling in the Remedial Action Assessment System (RAAS)  

SciTech Connect (OSTI)

There are numerous hazardous waste sites under the jurisdiction of the US Department of Energy (DOE). To assist the cleanup of these sites in a more consistent, timely, and cost-effective manner, the Remedial Action Assessment System (RAAS) is being developed by the Pacific Northwest Laboratory (PNL). RAAS is a software tool designed to automate the initial technology selection within the remedial investigation/feasibility study (RI/FS) process. The software does several things for the user: (1) provides information about available remedial technologies, (2) sorts possible technologies to recommend a list of technologies applicable to a given site, (3) points out technical issues that may prevent the implementation of a technology, and (4) provides an estimate of the effectiveness of a given technology at a particular site. Information from RAAS can be used to compare remediation options and guide selection of technologies for further study.

Johnson, C.D.; Bagaasen, L.M.; Chan, T.C.; Lamar, D.A.; Buelt, J.L.; Freeman, C.J.; Skeen, R.S.

1994-08-01T23:59:59.000Z

434

Fish Passage Assessment of an Advanced Hydropower Turbine and Conventional Turbine Using Blade-strike Modeling  

SciTech Connect (OSTI)

In the Columbia and Snake River basins, several species of Pacific salmon were listed under the Endangered Species Act of 1973 due to significant declines of fish population. Dam operators and design engineers are thus faced with the task of making those hydroelectric facilities more ecologically friendly through changes in hydro-turbine design and operation. Public Utility District No. 2 of Grant County, Washington, applied for re-licensing from the U.S. Federal Energy Regulatory Commission to replace the 10 turbines at Wanapum Dam with advanced hydropower turbines that were designed to increase power generation and improve fish passage conditions. We applied both deterministic and stochastic blade-strike models to the newly installed turbine and an existing turbine. Modeled probabilities were compared to the results of a large-scale live fish survival study and a sensor fish study under the same operational parameters. Overall, injury rates predicted by the deterministic model were higher than experimental rates of injury while those predicted by the stochastic model were in close agreement with experiment results. Fish orientation at the time of entry into the plane of the leading edges of the turbine runner blades was an important factor contributing to uncertainty in modeled results. The advanced design turbine had slightly higher modeled injury rates than the existing turbine design; however, there was no statistical evidence that suggested significant differences in blade-strike injuries between the two turbines and the hypothesis that direct fish survival rate through the advanced hydropower turbine is equal or better than that through the conventional turbine could not be rejected.

Deng, Zhiqun; Carlson, Thomas J.; Dauble, Dennis D.; Ploskey, Gene R.

2011-01-04T23:59:59.000Z

435

MELCOR 1.8.5 modeling aspects of fission product release, transport and deposition an assessment with recommendations.  

SciTech Connect (OSTI)

The Phebus and VERCORS data have played an important role in contemporary understanding and modeling of fission product release and transport from damaged light water reactor fuel. The data from these test programs have allowed improvement of MELCOR modeling of release and transport processes for both low enrichment uranium fuel as well as high burnup and mixed oxide (MOX) fuels. This paper discusses the synthesis of these findings in the MELCOR severe accident code. Based on recent assessments of MELCOR 1.8.5 fission product release modeling against the Phebus FPT-1 test and on observations from the ISP-46 exercise, modifications to the default MELCOR 1.8.5 release models are recommended. The assessments identified an alternative set of Booth diffusion parameters recommended by ORNL (ORNL-Booth), which produced significantly improved release predictions for cesium and other fission product groups. Some adjustments to the scaling factors in the ORNL-Booth model were made for selected fission product groups, including UO{sub 2}, Mo and Ru in order to obtain better comparisons with the FPT-1 data. The adjusted model, referred to as 'Modified ORNL-Booth,' was subsequently compared to original ORNL VI fission product release experiments and to more recently performed French VERCORS tests, and the comparisons was as favorable or better than the original CORSOR-M MELCOR default release model. These modified ORNL-Booth parameters, input to MELCOR 1.8.5 as 'sensitivity coefficients' (i.e. user input that over-rides the code defaults) are recommended for the interim period until improved release models can be implemented into MELCOR. For the case of ruthenium release in air-oxidizing conditions, some additional modifications to the Ru class vapor pressure are recommended based on estimates of the RuO{sub 2} vapor pressure over mildly hyperstoichiometric UO{sub 2}. The increased vapor pressure for this class significantly increases the net transport of Ru from the fuel to the gas stream. A formal model is needed. Deposition patterns in the Phebus FPT-1 circuit were also significantly improved by using the modified ORNL-Booth parameters, where retention of lower volatile Cs{sub 2}MoO{sub 4} is now predicted in the heated exit regions of the FPT-1 test, bringing down depositions in the FPT-1 steam generator tube to be in closer alignment with the experimental data. This improvement in 'RCS' deposition behavior preserves the overall correct release of cesium to the containment that was observed even with the default CORSOR-M model. Not correctly treated however is the release and transport of Ag to the FPT-1 containment. A model for Ag release from control rods is presently not available in MELCOR. Lack of this model is thought to be responsible for the underprediction by a factor of two of the total aerosol mass to the FPT-1 containment. It is suggested that this underprediction of airborne mass led to an underprediction of the aerosol agglomeration rate. Underprediction of the agglomeration rate leads to low predictions of the aerosol particle size in comparison to experimentally measured ones. Small particle size leads low predictions of the gravitational settling rate relative to the experimental data. This error, however, is a conservative one in that too-low settling rate would result in a larger source term to the environment. Implementation of an interim Ag release model is currently under study. In the course of this assessment, a review of MELCOR release models was performed and led to the identification of several areas for future improvements to MELCOR. These include upgrading the Booth release model to account for changes in local oxidizing/reducing conditions and including a fuel oxidation model to accommodate effects of fuel stoichiometry. Models such as implemented in the French ELSA code and described by Lewis are considered appropriate for MELCOR. A model for ruthenium release under air oxidizing conditions is also needed and should be included as part of a fuel oxidation model since fuel stoichiometry is a fundamen

Gauntt, Randall O.

2010-04-01T23:59:59.000Z

436

Interactive 3D landscape assessment models Lewis GILL, Eckart LANGE, Ed MORGAN, Daniela ROMANO  

E-Print Network [OSTI]

, interactive 3D visualisations are also used as landscape design tools with the Google Sketchup1 software being that this will simplify the enhancement of the mental model of the designer. 1 http://www.sketchup.com #12;L.Gill, E

Romano, Daniela

437

Modeling Techniques to Assess Long-term Reliability of Environmental Flows in Basin Scale Planning  

E-Print Network [OSTI]

Scale Planning Thesis directed by Edith Zagona One aspect of integrated water resources management of the rivers but management can help sustain the river ecosystem through modifications to reservoir operations be incorporated into the model to capture reservoir operations. Finally, after addressing the integration of new

438

Environmental Modeling and Assessment 6: 3555, 2001. 2001 Kluwer Academic Publishers. Printed in the Netherlands.  

E-Print Network [OSTI]

In order to help guide air pollution legislation at the European level, harmful air pollution effects. Ozone has been labeled as the most serious of the damaging air pollutants to agriculture, where growth for Denmark. Keywords: air pollution models, AOT40 values for ozone, damaging effects, economical evaluations

Dimov, Ivan

439

QUANTITATIVE ASSESSMENT OF THE IMPACT OF 3D MODELLING OF BUILDING STRUCTURES ON  

E-Print Network [OSTI]

to the firm's overall activity, because the greatest increase in productivity is achieved in this area; that construction companies can leverage the benefits in error reduction and logistics improvements that result PRODUCTIVITY Rafael Sacks1 and Ronen Barak2 ABSTRACT Parametric three-dimensional modelling of buildings

Sacks, Rafael

440

Risk assessment for the Waste Technologies Industries (WTI) hazardous waste incinerator facility (east Liverpool, Ohio). Volume 4. Atmospheric dispersion and deposition modeling of emissions. Draft report  

SciTech Connect (OSTI)

The report constitutes a comprehensive site-specific risk assessment for the WTI incineration facility located in East Liverpool, OH. Volume IV describes the air dispersion model used to estimate air concentrations and particle deposition, as well as the results of the modeling exercise.

NONE

1995-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "models assessing surface" 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

Potential impacts of climate change on tropospheric ozone in California: a preliminary episodic modeling assessment of the Los Angeles basin and the Sacramento valley  

SciTech Connect (OSTI)

In this preliminary and relatively short modeling effort, an initial assessment is made for the potential air quality implications of climate change in California. The focus is mainly on the effects of changes in temperature and related meteorological and emission factors on ozone formation. Photochemical modeling is performed for two areas in the state: the Los Angeles Basin and the Sacramento Valley.

Taha, Haider

2001-01-01T23:59:59.000Z

442

Paper presented at the 4th International Conference Working on Safety, Crete, Greece, 2008 Functional modeling for risk assessment of automation in a changing air  

E-Print Network [OSTI]

Functional modeling for risk assessment of automation in a changing air traffic management environment R or to let automation act autonomously. The Functional Resonance Analysis Method (FRAM) provides a framework from ERASMUS automation. Various instantiations of a partial model resulting from the application

Zhao, Yuxiao

443

Assessing the Vulnerability of Large Critical Infrastructure Using Fully-Coupled Blast Effects Modeling  

SciTech Connect (OSTI)

Structural failures, such as the MacArthur Maze I-880 overpass in Oakland, California and the I-35 bridge in Minneapolis, Minnesota, are recent examples of our national infrastructure's fragility and serve as an important reminder of such infrastructure in our everyday lives. These two failures, as well as the World Trade Center's collapse and the levee failures in New Orleans, highlight the national importance of protecting our infrastructure as much as possible against acts of terrorism and natural hazards. This paper describes a process for evaluating the vulnerability of critical infrastructure to large blast loads using a fully-coupled finite element approach. A description of the finite element software and modeling technique is discussed along with the experimental validation of the numerical tools. We discuss how such an approach can be used for specific problems such as modeling the progressive collapse of a building.

McMichael, L D; Noble, C R; Margraf, J D; Glascoe, L G

2009-03-26T23:59:59.000Z

444

Dose-Response Modeling for Life Cycle Impact Assessment: Findingsof the Portland Review Workshop  

SciTech Connect (OSTI)

The United Nations Environment Program (UNEP)/SETAC Life Cycle Initiative aims at putting life cycle thinking into practice and at improving the supporting tools for this process through better data and indicators. The initiative has thus launched three programs with associated working groups (see http://www.uneptie.org/pc/sustain/lcinitiative/). The Task Force on Toxic Impacts was established under the Life Cycle Impact Assessment (LCIA) program to establish recommended practice and guidance for use in human toxicity, ecosystem toxicity, and related categories with direct effects on human health and ecosystem health. The workshop consisted of three elements. (A) presentations summarizing (1) the goals of the LCIA Task Force (2) historical approaches to exposure and toxic impacts in LCIA (3) current alternative proposals for addressing human health impacts. Viewgraphs from two of these presentations are provided in Appendix B to this report. (B) Discussion among a panel of experts about the scientific defensibility of these historical and proposed approaches in the context of the goals of the LCIA Task Force 3 on toxicity impacts. (C) Development of the recommendations to the LCIA program and working group for optimum short- and long-term strategies for addressing human health impacts in LCA.

McKone, Thomas E.; Kyle, Amy D.; Jolliet, Olivier; Olsen, StigIrving; Hauschild, Michael

2006-06-01T23:59:59.000Z

445

The Hierarchical Rater Model for Rated Test Items and its Application to Large-Scale Educational Assessment Data  

E-Print Network [OSTI]

-ended (or "constructed response") test items have become a standard part of the educational assessment

446

Energy conservation potential of surface modification technologies  

SciTech Connect (OSTI)

This report assesses the energy conservation impact of surface modification technologies on the metalworking industries. The energy conservation impact of surface modification technologies on the metalworking industries is assessed by estimating their friction and wear tribological sinks and the subsequent reduction in these sinks when surface modified tools are used. Ion implantation, coatings, and laser and electron beam surface modifications are considered.

Le, H.K.; Horne, D.M.; Silberglitt, R.S.

1985-09-01T23:59:59.000Z

447

A Qualitative Readiness-Requirements Assessment Model for Enterprise Big-Data Infrastructure Investment  

SciTech Connect (OSTI)

In the last three decades, there has been an exponential growth in the area of information technology providing the information processing needs of data-driven businesses in government, science, and private industry in the form of capturing, staging, integrating, conveying, analyzing, and transferring data that will help knowledge workers and decision makers make sound business decisions. Data integration across enterprise warehouses is one of the most challenging steps in the big data analytics strategy. Several levels of data integration have been identified across enterprise warehouses: data accessibility, common data platform, and consolidated data model. Each level of integration has its own set of complexities that requires a certain amount of time, budget, and resources to implement. Such levels of integration are designed to address the technical challenges inherent in consolidating the disparate data sources. In this paper, we present a methodology based on industry best practices to measure the readiness of an organization and its data sets against the different levels of data integration. We introduce a new Integration Level Model (ILM) tool, which is used for quantifying an organization and data system s readiness to share data at a certain level of data integration. It is based largely on the established and accepted framework provided in the Data Management Association (DAMA-DMBOK). It comprises several key data management functions and supporting activities, together with several environmental elements that describe and apply to each function. The proposed model scores the maturity of a system s data governance processes and provides a pragmatic methodology for evaluating integration risks. The higher the computed scores, the better managed the source data system and the greater the likelihood that the data system can be brought in at a higher level of integration.

Olama, Mohammed M [ORNL] [ORNL; McNair, Wade [ORNL] [ORNL; Sukumar, Sreenivas R [ORNL] [ORNL; Nutaro, James J [ORNL] [ORNL

2014-01-01T23:59:59.000Z

448

Simple solar spectral model for direct and diffuse irradiance on horizontal and tilted planes at the earth's surface for cloudless atmospheres  

SciTech Connect (OSTI)

A new, simple model for calculating clear-sky direct and diffuse spectral irradiance on horizontal and tilted surfaces is presented. The model is based on previously reported simple algorithms and on comparisons with rigorous radiative transfer calculations and limited outdoor measurements. Equations for direct normal irradiance are outlined; and include: Raleigh scattering; aerosol scattering and absorption; water vapor absorption; and ozone and uniformly mixed gas absorption. Inputs to the model include solar zenith angle, collector tilt angle, atmospheric turbidity, amount of ozone and precipitable water vapor, surface pressure, and ground albedo. The model calculates terrestrial spectra from 0.3 to 4.0 ..mu..m with approximately 10 nm resolution. A major goal of this work is to provide researchers with the capability to calculate spectral irradiance for different atmospheric conditions and different collector geometries using microcomputers. A listing of the computer program is provided.

Bird, R.; Riordan, C.

1984-12-01T23:59:59.000Z

449

A New Model to Construct Ice Stream Surface Elevation Profiles and Calculate Contributions to Sea-Level Rise  

E-Print Network [OSTI]

to produce independent assessments of the state of polar iceproduce these predictions account for thermal expansion, changes in non-polar glaciers and ice

Adachi, Yosuke

2012-01-01T23:59:59.000Z

450

Modeling the effects of topography and wind on atmospheric dispersion of CO2 surface leakage at geologic carbon sequestration sites  

E-Print Network [OSTI]

CO 2 from geologic carbon sequestration sites, Vadose Zoneleakage at geologic carbon sequestration sites Fotini K.assessment for geologic carbon sequestration sites. We have

Chow, Fotini K.

2009-01-01T23:59:59.000Z

451

About the SimCCS model A cost surface, i.e. a raster grid of the cost to lay a  

E-Print Network [OSTI]

; · An "offshore scenario" exports CO2 towards the North sea through Normandy and toward an hypothetical storageA B C About the SimCCS model A cost surface, i.e. a raster grid of the cost to lay a pipeline across each grid cell, was estimated using geographical datasets including protected areas, existing gas

Boyer, Edmond

452

Ice stream basal conditions from block-wise surface data inversion and simple regression models of ice stream flow: Application to  

E-Print Network [OSTI]

Ice stream basal conditions from block-wise surface data inversion and simple regression models of ice stream flow: Application to Bindschadler Ice Stream O. V. Sergienko,1 R. A. Bindschadler,2 P. L; published 4 December 2008. [1] Widespread basal conditions controlling ice stream flows are still beyond

Boyce, C. Kevin

453

Ab Initio Study of the Interaction of Water with Cluster Models of the Aluminum Terminated (0001) r-Aluminum Oxide Surface  

E-Print Network [OSTI]

Ab Initio Study of the Interaction of Water with Cluster Models of the Aluminum Terminated (0001) r-Aluminum to hydroxylation of the aluminum terminated surface, the two water process was found to be the most exothermic, occurring within 10-2 s. I. Introduction As one of the most important ceramic materials, R-aluminum oxide

Schlegel, H. Bernhard

454

COMPARISON OF SEA SURFACE ROUGHNESS MODELS FOR OFFSHORE WIND POWER UTILISATION Bernhard Lange(1), Jrgen Hjstrup(2), Sren Larsen(2), Rebecca Barthelmie(2)  

E-Print Network [OSTI]

Large offshore wind farms are being built in several countries in Europe. The economic viabilityCOMPARISON OF SEA SURFACE ROUGHNESS MODELS FOR OFFSHORE WIND POWER UTILISATION Bernhard Lange(1 of such projects depends on the favourable wind conditions of offshore sites, since the higher energy yield has

Heinemann, Detlev

455