6,078 research outputs found
Lattice study on two-color QCD with six flavors of dynamical quarks
We study the dynamics of SU(2) gauge theory with NF=6 Dirac fermions by means
of lattice simulation to investigate if they are appropriate to realization of
electroweak symmetry breaking. The discrete analogue of beta function for the
running coupling constant defined under the Schroedinger functional boundary
condition are computed on the lattices up to linear size of L/a=24 and preclude
the existence of infrared fixed point below 7.6. Gluonic observables such as
heavy quark potential, string tension, Polyakov loop suggest that the target
system is in the confining phase even in the massless quark limit.Comment: 7 pages, 9 figures, Proceedings of The 30th International Symposium
on Lattice Field Theory, June 24-29, 2012, Cairns, Australi
Fractal analysis for the ULF data during the 1993 Guam earthquake to study prefracture criticality
International audienceAn extremely large earthquake (with magnitude of 8.2) happened on 8 August 1993 near the Guam island, and ultra-low-frequency (ULF) (frequency less than 1 Hz) electromagnetic fields were measured by 3-axis induction magnetometers at an observing station (with the epicentral distance of 65 km) with sampling frequency of 1 Hz. In order to study electromagnetic signature of prefracture criticality, we have undertaken the fractal (mono-fractal) analysis by means of the Higuchi's method for the ULF data during the 1993 Guam earthquake. Then, it is found that the fractal dimension exhibits five maxima 99, 75, 52, 21, and 9?4 days before the earthquake main shock, which suggests the ULF electromagnetic signature of nonlinear evolution (in the sense of self-organized criticality) taking place in the lithosphere just before the 1993 large Guam earthquake. That is, there take place step-like changes in the lithosphere during the long-term of the order of several months before the main shock
A frailty model for detecting number of faults in a system
A frailty model for failure data is proposed to estimate the total number of faults in a system. The Littlewood model and Jelinski-Moranda are the two particular cases of the proposed formulation. The two-stage estimating procedure, a conditional likelihood and a Horvitz-Thompson estimator, is found to be efficient. Simulation studies are given to assess the performance of the estimator. Two examples are also presented.published_or_final_versio
A Gibbs-sampler approach to estimate the number of faults in a system using capture-recapture sampling
A new recapture debugging model is suggested to estimate the number of faults in a system, ν, and the failure intensity of each fault, φ. The Gibbs sampler and the Metropolis algorithm are used in this inference procedure. A numerical illustration suggests a notable improvement on the estimation of ν and φ compared with that of a removal debugging model.published_or_final_versio
Hydrodynamic Description of Granular Convection
We present a hydrodynamic model that captures the essence of granular
dynamics in a vibrating bed. We carry out the linear stability analysis and
uncover the instability mechanism that leads to the appearance of the
convective rolls via a supercritical bifurcation of a bouncing solution. We
also explicitly determine the onset of convection as a function of control
parameters and confirm our picture by numerical simulations of the continuum
equations.Comment: 14 pages, RevTex 11pages + 3 pages figures (Type csh
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