8,849 research outputs found
Holding Dissapearance in RTD-based Quantizers
Multiple-valued Logic (MVL) circuits are one of the most attractive
applications of the Monostable-to-Multistable transition Logic (MML), and they
are on the basis of advanced circuits for communications. The operation of such
quantizer has two steps : sampling and holding. Once the quantizer samples the
signal, it must maintain the sampled value even if the input changes. However,
holding property is not inherent to MML circuit topologies. This paper analyses
the case of an MML ternary inverter used as a quantizer, and determines the
relations that circuit representative parameters must verify to avoid this
malfunction.Comment: Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions
Solution to the Isotropy Problem for Cosmological Hidden Vector Models
Gauge bosons associated to new gauge symmetries under which the standard
model particles are not charged are predicted in many extensions of the
standard model of particles and interactions. We show that under very general
conditions, the average energy-momentum tensor of these rapidly oscillating
vector fields is isotropic for any locally inertial observer. This result has a
fundamental importance in order to consider coherent vector fields as a viable
alternative to support models of dark matter, dark energy or inflation.Comment: 4 pages, 1 figure. Contributed to the 9th Patras Workshop on Axions,
WIMPs and WISPs, Mainz, June 24-28, 201
Spherical harmonic decomposition applied to spatial-temporal analysis of human high-density EEG
We demonstrate an application of spherical harmonic decomposition to analysis
of the human electroencephalogram (EEG). We implement two methods and discuss
issues specific to analysis of hemispherical, irregularly sampled data.
Performance of the methods and spatial sampling requirements are quantified
using simulated data. The analysis is applied to experimental EEG data,
confirming earlier reports of an approximate frequency-wavenumber relationship
in some bands.Comment: 12 pages, 8 figures, submitted to Phys. Rev. E, uses APS RevTeX
style
Explicit computations of low lying eigenfunctions for the quantum trigonometric Calogero-Sutherland model related to the exceptional algebra E7
In the previous paper math-ph/0507015 we have studied the characters and
Clebsch-Gordan series for the exceptional Lie algebra E7 by relating them to
the quantum trigonometric Calogero-Sutherland Hamiltonian with coupling
constant K=1. Now we extend that approach to the case of general K
Swift observations of the 2015 outburst of AG Peg -- from slow nova to classical symbiotic outburst
Symbiotic stars often contain white dwarfs with quasi-steady shell burning on
their surfaces. However, in most symbiotics, the origin of this burning is
unclear. In symbiotic slow novae, however, it is linked to a past thermonuclear
runaway. In June 2015, the symbiotic slow nova AG Peg was seen in only its
second optical outburst since 1850. This recent outburst was of much shorter
duration and lower amplitude than the earlier eruption, and it contained
multiple peaks -- like outbursts in classical symbiotic stars such as Z And. We
report Swift X-ray and UV observations of AG Peg made between June 2015 and
January 2016. The X-ray flux was markedly variable on a time scale of days,
particularly during four days near optical maximum, when the X-rays became
bright and soft. This strong X-ray variability continued for another month,
after which the X-rays hardened as the optical flux declined. The UV flux was
high throughout the outburst, consistent with quasi-steady shell burning on the
white dwarf. Given that accretion disks around white dwarfs with shell burning
do not generally produce detectable X-rays (due to Compton-cooling of the
boundary layer), the X-rays probably originated via shocks in the ejecta. As
the X-ray photo-electric absorption did not vary significantly, the X-ray
variability may directly link to the properties of the shocked material. AG
Peg's transition from a slow symbiotic nova (which drove the 1850 outburst) to
a classical symbiotic star suggests that shell burning in at least some
symbiotic stars is residual burning from prior novae.Comment: Accepted by MNRAS 23 June 2016. Manuscript submitted in original form
5 April 201
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