3,365 research outputs found
Performance of SSE and AVX Instruction Sets
SSE (streaming SIMD extensions) and AVX (advanced vector extensions) are SIMD
(single instruction multiple data streams) instruction sets supported by recent
CPUs manufactured in Intel and AMD. This SIMD programming allows parallel
processing by multiple cores in a single CPU. Basic arithmetic and data
transfer operations such as sum, multiplication and square root can be
processed simultaneously. Although popular compilers such as GNU compilers and
Intel compilers provide automatic SIMD optimization options, one can obtain
better performance by a manual SIMD programming with proper optimization: data
packing, data reuse and asynchronous data transfer. In particular, linear
algebraic operations of vectors and matrices can be easily optimized by the
SIMD programming. Typical calculations in lattice gauge theory are composed of
linear algebraic operations of gauge link matrices and fermion vectors, and so
can adopt the manual SIMD programming to improve the performance.Comment: 7 pages, 5 figures, 4 tables, Contribution to proceedings of the 30th
International Symposium on Lattice Field Theory (Lattice 2012), June 24-29,
201
Quality Assurance Testing for Screening Defective Aluminum Die-cast Rotors of Squirrel Cage Induction Machines
Charge density functional plus calculation of lacunar spinel GaMSe (M = Nb, Mo, Ta, and W)
Charge density functional plus calculations are carried out to examine
the validity of molecular =1/2 and 3/2 state in lacunar spinel
GaMX (M = Nb, Mo, Ta, and W). With LDA (spin-unpolarized local density
approximation), which has recently been suggested as the more desirable
choice than LSDA (local spin density approximation), we examine the band
structure in comparison with the previous prediction based on the
spin-polarized version of functional and with the prototypical
=1/2 material SrIrO. It is found that the previously
suggested =1/2 and 3/2 band characters remain valid still in
LDA calculations while the use of charge-only density causes some minor
differences. Our result provides the further support for the novel molecular
state in this series of materials, which can hopefully motivate
the future exploration toward its verification and the further search for new
functionalities
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