24,647 research outputs found
Visco-elastic regularization and strain softening
In this paper it is intended to verify the capacity of regularization of the numerical
solution of an elasto-plastic problem with linear strain softening. The finite element method
with a displacement approach is used. Drucker-Prager yield criteria is considered. The radial
return method is used for the integration of the elasto-plastic constitutive relations. An elastovisco-
plastic scheme is used to regularize the numerical solution. Two constitutive laws have
been developed and implemented in a FE-program, the first represent the radial return
method applied to Drucker-Prager yield criteria and the second is a time integration
procedure for the Maxwell visco-elastic model. Attention is paid to finite deformations. An
associative plastic flow is considered in the Drucker-Prager elasto-plastic model. The
algorithms are tested in two problems with softening. Figures showing the capability of the
algorithms to regularize the solution are presented
Landau Gauge Fixing on GPUs and String Tension
We explore the performance of CUDA in performing Landau gauge fixing in
Lattice QCD, using the steepest descent method with Fourier acceleration. The
code performance was tested in a Tesla C2070, Fermi architecture. We also
present a study of the string tension at finite temperature in the confined
phase. The string tension is extracted from the color averaged free energy and
from the color singlet using Landau gauge fixing.Comment: 7 pages, 4 figures, 1 table. Contribution to the International
Meeting "Excited QCD", Peniche, Portugal, 06 - 12 May 201
Landau gauge fixing on the lattice using GPU's
In this work, we consider the GPU implementation of the steepest descent
method with Fourier acceleration for Laudau gauge fixing, using CUDA. The
performance of the code in a Tesla C2070 GPU is compared with a parallel CPU
implementation.Comment: 3 pages, 1 figure, Proceedings of the Xth Quark Confinement and the
Hadron Spectrum, 8-12 October 2012, TUM Campus Garching, Munich, German
Gluons at finite temperature
The gluon propagator is investigated at finite temperature via lattice simulations. In particular, we discuss its interpretation as a massive-type bosonic propagator. Moreover, we compute the corresponding spectral density and study the violation of spectral positivity. Finally, we explore the dependence of the gluon propagator on the phase of the Polyakov loop
Energy efficiency of social housing existing buildings – a portuguese case study
The European energy performance building regulations, Directive 2002/91/EC - Energy Performance of
Buildings Directive (EPBD) of the European Parliament and Council, require that new buildings present
minimum standards of energy efficiency. Accordingly the Portuguese regulations require that new buildings
comply with minimum requirements on the energy performance and must have an energy performance
certification through witch an energy efficiency label is attributed to the housing. It also require that existing
buildings must have an efficiency energy label when submitted to a commercial transaction or to a deep
rehabilitation. To achieve this goal the study of energy performance of existing buildings must be done. As
many essentials elements to determine the U-factor and other thermal parameters are unknown, Portugal
developed a simplified methodology to achieve the thermal performance of existing buildings. The aim of this
paper is to present the study of the energy performance of a set of social dwellings that were constructed during
the decade of 80, constructed before the former building thermal comfort specifications came into force. During
the study the referred methodology was applied and conclusions of the energy efficiency label obtained were put
out as the encountered difficulties. The study also compares the results obtained by the simplified methodology
and by the detailed methodology that is required by Portuguese building thermal comfort specifications
Book review: Brave new words: how AI will revolutionize education
In Brave New Words, Salman Khan argues that educators should harness AI’s potential to transform learning through personalised tutoring services like his own platform, Khanmigo. Although Khan’s book lacks an examination of how the broader spectrum of generative AI could disrupt education practices, he presents a captivating vision for how it can be used to enhance teaching and assessments and complement traditional classroom experiences, writes Jon Cardoso-Silva
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