5,273 research outputs found
Improving Memory Hierarchy Utilisation for Stencil Computations on Multicore Machines
Although modern supercomputers are composed of multicore machines, one can
find scientists that still execute their legacy applications which were
developed to monocore cluster where memory hierarchy is dedicated to a sole
core. The main objective of this paper is to propose and evaluate an algorithm
that identify an efficient blocksize to be applied on MPI stencil computations
on multicore machines. Under the light of an extensive experimental analysis,
this work shows the benefits of identifying blocksizes that will dividing data
on the various cores and suggest a methodology that explore the memory
hierarchy available in modern machines
Importância da avaliação microbiológica na qualidade e segurança dos alimentos.
Abordagem técnológica. Abordagem metodológica. Relevância econômica, social e ambiental. Referências bibliográficasbitstream/CNPAB-2010/27380/1/doc120.pd
Five-Dimensional QED, Muon Pair Production and Correction to the Coulomb Potential
We consider QED in five dimensions in a configuration where matter is
localized on a 3-brane while foton propagates in the bulk. The idea is to
investigate the effects of the Kaluza-Klein modes of the photon in the
relativistic regime, but in low energy, and in the nonrelativistic regime. In
the relativistic regime, we calculate the cross section for the reaction . We compare our theoretical result with a precise
measurement of this cross section at GeV. As result, we
extract a lower bound on the size of the extra dimension. In the
nonrelativistic regime, we derive the contribution for the Coulomb potential
due to the whole tower of the Kaluza-Klein excited modes of the photon. We use
the modified potential to calculate the Rutherford scattering differential
cross section.Comment: minor changes, three new refs. added, to appear in IJMP
On the effective action of the vacuum photon splitting in Lorentz-violating QED
We consider one-loop radiative corrections from Lorentz- and CPT- violating
extended QED to address the specific problem of finding explicitly an effective
action describing amplitude of photon triple splitting. We show that it is not
possible to find a nonzero photon triple splitting effective action, at least
by using the derivative expansion method (at zero external momenta), up to
leading order in the Lorentz- and CPT- violating parameter.Comment: 4 pages, version to appear in EP
Divergência genética entre genótipos de aceroleira da Embrapa Semiárido.
O presente trabalho teve como objetivo a análise da divergência genética em um grupo de genótipos de aceroleira do programa de melhoramento genético da Embrapa Semiárido
Divergência fenotípica em acessos de aceroleira da Embrapa Semiárido.
O presente trabalho objetivou analisar a divergência entre 35 acessos do Banco de Germoplasma de aceroleira da Embrapa Semiárido, em Petrolina, PE
Caracterização preliminar de acessos de aceroleira da Embrapa Semiárido.
O presente trabalho objetivou a caracterização preliminar dos acessos do Banco Ativo de Germoplasma (BAG) de Aceroleira da Embrapa Semiárido
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