37,645 research outputs found
Non-minimal Higgs inflation in the context of warm scenario in the light of Planck data
We investigate the non-minimally Higgs inflaton (HI) model in the context of
warm inflation scenario. Warm little inflaton (WLI) model considers the little
Higgs boson as inflaton. The concerns of warm inflation model can be eliminated
in WLI model. There is a special case of dissipation parameter in WLI model
. Using this parameter, we study the potential of HI in
Einstein frame . Finally we will constrain the parameters of our model using
current Planck observational data.Comment: 6 pages, 4 figures, the paper has been accepted by EPJ
White Light Interferometry for Quantitative Surface Characterization in Ion Sputtering Experiments
White light interferometry (WLI) can be used to obtain surface morphology
information on dimensional scale of millimeters with lateral resolution as good
as ~1 {\mu}m and depth resolution down to 1 nm. By performing true
three-dimensional imaging of sample surfaces, the WLI technique enables
accurate quantitative characterization of the geometry of surface features and
compares favorably to scanning electron and atomic force microscopies by
avoiding some of their drawbacks. In this paper, results of using the WLI
imaging technique to characterize the products of ion sputtering experiments
are reported. With a few figures, several example applications of the WLI
method are illustrated when used for (i) sputtering yield measurements and
time-to-depth conversion, (ii) optimizing ion beam current density profiles,
the shapes of sputtered craters, and multiple ion beam superposition and (iii)
quantitative characterization of surfaces processed with ions. In particular,
for sputter depth profiling experiments of 25Mg, 44Ca and 53Cr ion implants in
Si (implantation energy of 1 keV per nucleon), the depth calibration of the
measured depth profile curves determined by the WLI method appeared to be
self-consistent with TRIM simulations for such projectile-matrix systems. In
addition, high depth resolution of the WLI method is demonstrated for a case of
a Genesis solar wind Si collector surface processed by gas cluster ion beam: a
12.5 nm layer was removed from the processed surface, while the transition
length between the processed and untreated areas was 150 {\mu}m.Comment: Applied Surface Science, accepted: 7 pages and 8 figure
Non-Gaussian Discriminative Factor Models via the Max-Margin Rank-Likelihood
We consider the problem of discriminative factor analysis for data that are
in general non-Gaussian. A Bayesian model based on the ranks of the data is
proposed. We first introduce a new {\em max-margin} version of the
rank-likelihood. A discriminative factor model is then developed, integrating
the max-margin rank-likelihood and (linear) Bayesian support vector machines,
which are also built on the max-margin principle. The discriminative factor
model is further extended to the {\em nonlinear} case through mixtures of local
linear classifiers, via Dirichlet processes. Fully local conjugacy of the model
yields efficient inference with both Markov Chain Monte Carlo and variational
Bayes approaches. Extensive experiments on benchmark and real data demonstrate
superior performance of the proposed model and its potential for applications
in computational biology.Comment: 14 pages, 7 figures, ICML 201
Quantumlike Chaos in the Frequency Distributions of the Bases A, C, G, T in Drosophila DNA
Continuous periodogram power spectral analyses of fractal fluctuations of
frequency distributions of bases A, C, G, T in Drosophila DNA show that the
power spectra follow the universal inverse power-law form of the statistical
normal distribution. Inverse power-law form for power spectra of space-time
fluctuations is generic to dynamical systems in nature and is identified as
self-organized criticality. The author has developed a general systems theory,
which provides universal quantification for observed self-organized criticality
in terms of the statistical normal distribution. The long-range correlations
intrinsic to self-organized criticality in macro-scale dynamical systems are a
signature of quantumlike chaos. The fractal fluctuations self-organize to form
an overall logarithmic spiral trajectory with the quasiperiodic Penrose tiling
pattern for the internal structure. Power spectral analysis resolves such a
spiral trajectory as an eddy continuum with embedded dominant wavebands. The
dominant peak periodicities are functions of the golden mean. The observed
fractal frequency distributions of the Drosophila DNA base sequences exhibit
quasicrystalline structure with long-range spatial correlations or
self-organized criticality. Modification of the DNA base sequence structure at
any location may have significant noticeable effects on the function of the DNA
molecule as a whole. The presence of non-coding introns may not be redundant,
but serve to organize the effective functioning of the coding exons in the DNA
molecule as a complete unit.Comment: 46 pages, 9 figure
Second order parameter-uniform convergence for a finite difference method for a singularly perturbed linear reaction-diffusion system
A singularly perturbed linear system of second order ordinary differential
equations of reaction-diffusion type with given boundary conditions is
considered. The leading term of each equation is multiplied by a small positive
parameter. These singular perturbation parameters are assumed to be distinct.
The components of the solution exhibit overlapping layers. Shishkin
piecewise-uniform meshes are introduced, which are used in conjunction with a
classical finite difference discretisation, to construct a numerical method for
solving this problem. It is proved that the numerical approximations obtained
with this method is essentially second order convergent uniformly with respect
to all of the parameters
Can winds driven by active galactic nuclei account for the extragalactic gamma-ray and neutrino backgrounds?
Various observations are revealing the widespread occurrence of fast and
powerful winds in active galactic nuclei (AGNs) that are distinct from
relativistic jets, likely launched from accretion disks and interacting
strongly with the gas of their host galaxies. During the interaction, strong
shocks are expected to form that can accelerate non-thermal particles to high
energies. Such winds have been suggested to be responsible for a large fraction
of the observed extragalactic gamma-ray background (EGB) in the GeV-TeV range
and the diffuse neutrino background in the PeV range, via the decay of neutral
and charged pions generated in inelastic collisions between protons
accelerated by the forward shock and the ambient gas. However, previous studies
did not properly account for processes such as adiabatic losses that may reduce
the gamma-ray and neutrino fluxes significantly. We evaluate the production of
gamma-rays and neutrinos by AGN-driven winds in some detail by modeling their
hydrodynamic and thermal evolution, including the effects of their
two-temperature structure. We find that they can only account for less than
% of the EGB flux, as otherwise the model would violate the
independent upper limit derived from the diffuse isotropic gamma-ray
background. If the neutrino spectral index is steep with , a
severe tension with the isotropic gamma-ray background would arise as long as
the winds contribute more than % of the IceCube neutrino flux in the
TeV range. Nevertheless, at energies ~TeV, we find that the
IceCube neutrino flux may still be accountable by AGN-driven winds if the
spectral index is as small as . The detectability of
gamma-ray point sources also provides important constraints on such scenarios.Comment: 17 pages, 10 figures, to appear in Ap
Detection of neoplasia using dye spray chromoendoscopy in patients with a high risk of familial colorectal cancer
Intelligent multimedia communication for enhanced medical e-collaboration in back pain treatment
This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2004 SAGE PublicationsRemote, multimedia-based, collaboration in back pain treatment is an option which only recently has come to the attention of clinicians and IT providers. The take-up of such applications will inevitably depend on their ability to produce an acceptable level of service over congested and unreliable public networks. However, although the problem of multimedia application-level performance is closely linked to both the user perspective of the experience as well as to the service provided by the underlying network, it is rarely studied from an integrated viewpoint. To alleviate this problem, we propose an intelligent mechanism that integrates user-related requirements with the more technical characterization of quality of service, obtaining a priority order of low-level quality of service parameters, which would ensure that user-centred quality of perception is maintained at an optimum level. We show how our framework is capable of suggesting appropriately tailored transmission protocols, by incorporating user requirements in the remote delivery of e-health solutions
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