NEXUS FRAMEWORK FOR WHOLE-CORE FUEL PERFORMANCE: CURRENT APPLICATIONS AND FUTURE TRENDS

Current industry practice in fuel licensing often relies on thermo-mechanical modeling of a fuel rod with an artificially constructed bounding power history. The benefit of this approach is that it is computationally efficient; however, the drawbacks are that 1) such an approach is not always conservative, for instance when modelling phenomena related to late onset pellet-clad gap closure; and 2) it can poorly estimate available safety margins for fuel operating at high local power densities and/or to high burnup. For these reasons NNL developed an in-house whole-core fuel performance framework – NEXUS – to enable modelling of all fuel rods in the core using the ENIGMA fuel performance code and computed power histories from core simulation packages (currently limited to PARCS or SIMULATE). One of the main objectives was to create a tool that was both computationally efficient and user friendly. The former was achieved by making use of parallelisable architecture, while the latter was achieved by minimising necessary user input and providing tools for easy interrogation of the fuel performance output. NEXUS has been applied to several LWR operational scenarios, which we summarise in this paper, including steady-state operation of an ABWR, and a rod ejection accident in a small modular soluble boron free PWR and a GWe-class PWR. We also summarise current development activities related to integrating NNL’s in-house fuel performance Monte Carlo uncertainty analysis software CASINO into the NEXUS framework.

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Analytical Electron Microscopy Characterization of Electric Arc Furnace Dust

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100097326 ◽

1981 ◽

Vol 39 ◽

pp. 134-135

Author(s):

J. R. Porter ◽

J. I. Goldstein ◽

D. B. Williams

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Electric Arc Furnace ◽

Electric Arc ◽

Dust Particles ◽

Particle Analysis ◽

Arc Furnace ◽

Analytical Electron ◽

Residual Elements ◽

Industry Practice

Alloy scrap metal is increasingly being used in electric arc furnace (EAF) steelmaking and the alloying elements are also found in the resulting dust. A comprehensive characterization program of EAF dust has been undertaken in collaboration with the steel industry and AISI. Samples have been collected from the furnaces of 28 steel companies representing the broad spectrum of industry practice. The program aims to develop an understanding of the mechanisms of formation so that procedures to recover residual elements or recycle the dust can be established. The multi-phase, multi-component dust particles are amenable to individual particle analysis using modern analytical electron microscopy (AEM) methods.Particles are ultrasonically dispersed and subsequently supported on carbon coated formvar films on berylium grids for microscopy. The specimens require careful treatment to prevent agglomeration during preparation which occurs as a result of the combined effects of the fine particle size and particle magnetism. A number of approaches to inhibit agglomeration are currently being evaluated including dispersal in easily sublimable organic solids and size fractioning by centrifugation.

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Late onset systemic lupus erythematosus with elevated CA125 and gastrointestinal ischaemia

Internal Medicine Journal ◽

10.1046/j.1445-5994.2002.00180.x ◽

2002 ◽

Vol 32 (3) ◽

pp. 117-118 ◽

Cited By ~ 4

Author(s):

M. S. Koh ◽

K. Sunil ◽

H. S. Howe

Keyword(s):

Systemic Lupus Erythematosus ◽

Lupus Erythematosus ◽

Late Onset ◽

Systemic Lupus ◽

Onset Systemic Lupus Erythematosus

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Late-Onset Anaphylaxis to Omalizumab Reported

Skin & Allergy News ◽

10.1016/s0037-6337(06)71283-9 ◽

2006 ◽

Vol 37 (6) ◽

pp. 6

Author(s):

PATRICE WENDLING

Keyword(s):

Late Onset

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Early-, Late-Onset Psoriasis Called Different Diseases

Skin & Allergy News ◽

10.1016/s0037-6337(11)70427-2 ◽

2011 ◽

Vol 42 (8) ◽

pp. 26

Author(s):

BRUCE JANCIN

Keyword(s):

Late Onset ◽

Early Late

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Abstract #711 A Case of Late Onset Polyglandular Autoimmune Syndrome

Endocrine Practice ◽

10.1016/s1530-891x(20)47263-5 ◽

2018 ◽

Vol 24 ◽

pp. 156-157

Author(s):

Mingxue Arguello ◽

Ali Mrad

Keyword(s):

Late Onset ◽

Polyglandular Autoimmune Syndrome ◽

Autoimmune Syndrome

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An Input–Process–Output Model of Pilot Core Competencies

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000120 ◽

2017 ◽

Vol 7 (2) ◽

pp. 78-85 ◽

Cited By ~ 5

Author(s):

Heikki Mansikka ◽

Don Harris ◽

Kai Virtanen

Keyword(s):

Path Analysis ◽

Team Performance ◽

Core Competencies ◽

Core Competency ◽

Principal Component ◽

Analysis Model ◽

Input Process ◽

The Core ◽

Performance Framework ◽

Process Output

Abstract. The aim of this study was to investigate the relationship between the flight-related core competencies for professional airline pilots and to structuralize them as components in a team performance framework. To achieve this, the core competency scores from a total of 2,560 OPC (Operator Proficiency Check) missions were analyzed. A principal component analysis (PCA) of pilots’ performance scores across the different competencies was conducted. Four principal components were extracted and a path analysis model was constructed on the basis of these factors. The path analysis utilizing the core competencies extracted adopted an input–process–output’ (IPO) model of team performance related directly to the activities on the flight deck. The results of the PCA and the path analysis strongly supported the proposed IPO model.

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