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L. Nicolas M. Durin V. Koundy Eric Mathet A. Bucalossi P. Eisert J. Sievers L. Humphries J. Smith V. Pistora K. Ikonen 《Nuclear Engineering and Design》2003,223(3):263-277
The subject of this paper is to compare the results of the different calculations performed by the benchmark participants in the framework of the OECD Lower Head Failure (OLHF) program. The benchmark consists in the finite element (FE) calculation or in analytical calculations of the mechanical behavior of the OLHF-1 experiment. Seven participants from six countries and seven companies or organizations (AVN, VTT, GRS, UJV, SNL, IPSN and CEA) have performed the benchmark.The OLHF experiment program extends the NRC-sponsored SNL LHF program (NUREG/CR-5582) completed in 1998: these experiments where intended to simulate the thermal/mechanical loads to a 1/4.85-scale model of a reactor pressure vessel. The pressure vessel material (SA533B1 steel) used in these experiments is prototypic of reactor PWR vessel material and has been well characterized by material property testing as part of this program. The OLHF tests advance the results of the previous testing program by examining the effects of large temperature differences across the vessel wall. Large temperature differences in excess of 150–400 K are more prototypic of accident conditions.Most of the participants performed 2-D axisymmetric analyses and doesn’t study the crack opening. The global mechanical behaviour of OLHF-1 experiment is well represented but prediction of the maximum vertical displacement is not in good agreement with the experimental value. Failure time and location are in quite good agreement with experimental results but large discrepancies are observed on the mode of failure: creep or plasticity. To improve predictions, more investigation and work is needed on the choice of the failure criteria and failure mode. 相似文献
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Bob Eisenberg 《Journal of Computational Electronics》2002,1(3):331-333
Ion channels are proteins with a hole down their middle important in a wide range of biological functions yet simple enough to be analyzed as devices in the engineering tradition. 相似文献
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This paper provides a postcolonial policy analysis of the Education Sector Development Plan: 2000-2005 and Beyond in the small Caribbean island nation of St Lucia. The specific focus is upon the nature of the lifelong learning policy as incorporated in the Plan. This is shown to be a globalised policy discourse. Drawing on a number of postcolonial theorists, the paper works with a concept of the postcolonial as an aspirational politics. Bourdieu's concept of 'national capital' is also utilised in the analysis in relation to the attempt to manage some autonomy for the nation in the process of policy text production in education. The analysis demonstrates the way a postcolonial politics, manifest as strengthening national capital, worked in relation to the production of the Plan in its consultative mode of production and in its extensive cross-sector coverage. However, the analysis also shows evidence of the effects of residues of the colonial past in the hegemony of English in the Plan's recommendations, in the restriction of lifelong learning facilitation to schools and in the denial of a place for indigenous knowledges. The mode of lifelong learning supported is also dominated by a human capital framework and neglect of other capitals (social, cultural, etc.) for constituting what might be seen as a postcolonial and creole learning society. The paper also reflects upon the extent of the postcoloniality of the analysis provided. 相似文献
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Bellovin Steven M. Benzel Terry V. Blakley Bob Denning Dorothy E. Diffie Whitfield Epstein Jeremy Verissimo Paulo 《Security & Privacy, IEEE》2008,6(1):16-23
A virtual roundtable (featuring panelists Steven Bellovin, Terry Benzel, Bob Blakely, Dorothy Denning, Whitfield Diffie, Jeremy Epstein, and Paulo Verissimo) discussing the next 15 years in computer security. 相似文献
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回首过去,我们发现在RFID的发展方面,2006年已经成为"一方面与另一方面"的一年. 相似文献
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The Wabash River Integrated Methanol and Power Production from Clean Coal Technologies (IMPPCCT) project is investigating an Early Entrance Coproduction Plant (EECP) concept to evaluate integrated electrical power generation and methanol production from coal and other carbonaceous feedstocks. Research, development and testing (RD&T) that is currently being conducted under the project is evaluating cost effective process systems for removing contaminants, particularly sulfur species, from the generated gas which contains mainly synthesis gas (syngas), CO2 and steam at concentrations acceptable for the methanol synthesis catalyst. The RD&T includes laboratory testing followed by bench-scale and field testing at the SG Solutions Gasification Plant located in West Terre Haute, Indiana. Actual synthesis gas produced by the plant was utilized at system pressure and temperature for bench-scale field testing. 相似文献
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