1,527 research outputs found
The dependence of strange hadron multiplicities on the speed of hadronization
Hadron multiplicities are calculated in the ALCOR model for the Pb+Pb
collisions at CERN SPS energy. Considering the newest experimental results, we
display our prediction obtained from the ALCOR model for stable hadrons
including strange baryons and anti-baryons.Comment: 8 pages, LaTeX in IOP style, appeared in the Proceedings of
Strangeness'97 Conference, Santorini, April 14-18 1997, J. of Physics G23
(1997) 194
An in-depth look at prior art in fast round-robin arbiter circuits
Arbiters are found where shared resources exist such as busses, switching fabrics, processing elements. Round-robin is a fair arbitration method, where requestors get near-equal shares of a common resource or service. Round-robin arbitration (RRA) finds use in network switches/routers and processor boards/systems as well as many other applications that have concurrency. Today's electronic systems require arbiters with hundreds of ports (e.g., switching fabrics with virtual I/O queues) and clock speeds near the limits of even the latest microelectronics fabrication processes/libraries. Achieving high clock speeds in the presence of large number of ports is only possible with highly parallel arbiter architectures. This paper presents an in-depth literature survey of previous work on this problem. It looks at RRA work in the literature in a bigger context, then defines the typical RRA problem (RRA_typical), and specifically investigates work on fast architectures that solve the RRA_typical problem. There are five such works that are really competitive. This report takes a very in-depth look at these works. It explains each architecture and how/why it works from a unique perspective that cannot be found in the original publication of that architecture. It also proposes improvements to these architectures. We wrote generators for the improved versions of these architectures. We will share a summary of synthesis results in this report – although a detailed account of how these results were obtained and their analysis is the subject of another (upcoming) publicatio
Hard and soft probe - medium interactions in a 3D hydro+micro approach at RHIC
We utilize a 3D hybrid hydro+micro model for a comprehensive and consistent
description of soft and hard particle production in ultra-relativistic
heavy-ion collisions at RHIC. In the soft sector we focus on the dynamics of
(multi-)strange baryons, where a clear strangeness dependence of their
collision rates and freeze-out is observed. In the hard sector we study the
radiative energy loss of hard partons in a soft medium in the multiple soft
scattering approximation. While the nuclear suppression factor does
not reflect the high quality of the medium description (except in a reduced
systematic uncertainty in extracting the quenching power of the medium), the
hydrodynamical model also allows to study different centralities and in
particular the angular variation of with respect to the reaction
plane, allowing for a controlled variation of the in-medium path-length.Comment: 5 pages, 4 figures, Quark Matter 2006 proceedings, to appear in
Journal of Physics
Ultrafast sublattice pseudospin relaxation in graphene probed by polarization-resolved photoluminescence
Electronic pseudospin degrees of freedom in two-dimensional materials exhibit unique carrier-field interactions which allow for advanced control strategies. Here, we investigate ultrafast sublattice pseudospin relaxation in graphene by means of polarization-resolved photoluminescence spectroscopy. A comparison with microscopic Boltzmann simulations allows us to determine a lifetime of the optically aligned pseudospin distribution of 12±2fs. This experimental approach extends the toolbox of graphene pseudospintronics, providing additional means to investigate pseudospin dynamics in active devices or under external fields
Hydrogen Motion in Magnesium Hydride by NMR
In coarse-grained MgH2, the diffusive motion of hydrogen remains too slow (<10^5 hops s^−1) to narrow the H NMR line up to 400 °C. Slow-motion dipolar relaxation time T1D measurements reveal the motion, with hopping rate ωH from 0.1 to 430 s^−1 over the range of 260 to 400 °C, the first direct measurement of H hopping in MgH2. The ωH data are described by an activation energy of 1.72 eV (166 kJ/mol) and attempt frequency of 2.5 × 10^15 s^−1. In ball-milled MgH2 with 0.5 mol % added Nb2O5 catalyst, line-narrowing is evident already at 50 °C. The line shape shows distinct broad and narrow components corresponding to immobile and mobile H, respectively. The fraction of mobile H grows continuously with temperature, reaching ∼30% at 400 °C. This demonstrates that this material’s superior reaction kinetics are due to an increased rate of H motion, in addition to the shorter diffusion paths from ball-milling. In ball-milled MgH2 without additives, the line-narrowed component is weaker and is due, at least in part, to trapped H2 gas. The spin−lattice relaxation rates T1^−1 of all materials are compared, with ball-milling markedly increasing T1^−1. The weak temperature dependence of T1^−1 suggests a mechanism with paramagnetic relaxation centers arising from the mechanical milling
The Effect of Large Amplitude Fluctuations in the Ginzburg-Landau Phase Transition
The lattice Ginzburg-Landau model in d=3 and d=2 is simulated, for different
values of the coherence length in units of the lattice spacing , using
a Monte Carlo method. The energy, specific heat, vortex density , helicity
modulus and mean square amplitude are measured to map the phase
diagram on the plane . When amplitude fluctuations, controlled by the
parameter , become large () a proliferation of vortex
excitations occurs changing the phase transition from continuous to first
order.Comment: 4 pages, 5 postscript (eps) figure
Hadronization of massive quark matter
We present a fast hadronization model for the constituent quark plasma (CQP)
produced in relativistic heavy ion collisions at SPS. The model is based on
rate equations and on an equation of state inspired by the string
phenomenology. This equation of state has a confining character. We display the
time evolution of the relevant physical quantities during the hadronization
process and the final hadron multiplicities. The results indicate that the
hadronization of CQP is fast.Comment: 12 pages, Latex, 2 EPS figures, contribution to the Proceedings of
the 4th International Conference on Strangeness in Quark Matter (SQM'98),
Padova, Italy, 20-24 July 199
Cobalt ferrite based magnetostrictive materials for magnetic stress sensor and actuator applications
Magnetostrictive material based on cobalt ferrite is described. The cobalt ferrite is substituted with transition metals (such manganese (Mn), chromium (Cr), zinc (Zn) and copper (Cu) or mixtures thereof) by substituting the transition metals foriron or cobalt to form substituted cobalt ferrite that provides mechanical properties that make the substituted cobalt ferrite material effective for use as sensors andactuators. The substitution of transition metals lowers the Curie temperature of the material (as compared to cobalt ferrite) while maintaining a suitable magnetostriction for stress sensing applications
Effects of A17924G Genotypes Associated with Thioesterase Domain of Fatty Acid Synthase and K232A Genotypes of Diacylglycerol Acyltransferase-1 on Milk Fatty Acid Composition in Holstein Dairy Cows
The objective of this study was to determine if variations in single nucleotide polymorphism (SNP) in thioesterase domain of the fatty acid synthase (g.17924 A\u3eG Threonine\u3eAlanine) and in diacylglycerol acyltransferase-1 (g.10433/10434 GC/AA Alanine\u3eLysine) genes would explain variations in milk fatty acid composition among Holstein dairy cattle. About 200 cows participated in the study. Milk samples were collected monthly throughout the first ten months of lactation and analyzed for milk fatty acid composition by gas chromatography. Blood samples were used to obtain a DNA sample for each animal. Milk from cows with g.17924GG genotype had lower atherogenic index [AI; (12:0 + 4(14:0) + 16:0)/(MUFA + PUFA)] compared with milk from cows of g.17924AG genotype (P=0.007). Likewise, milk from cows with p.232AA genotype had lower AI compared with that from cows of p.232KK genotype (P\u3c0.016). The decrease in AI for cows with g.17924GG and p.232AA genotypes was achieved by the decrease in the concentration of palmitic acid (P=0.06 and P\u3c0.0001, respectively) and by the increase in the concentration of mono- and polyunsaturated fatty acids in milk for both genotypes. The results of this study indicate the potential of using earlier mentioned SNPs as DNA markers to select breeding animals that produce progeny with a healthier milk fatty acid composition
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