67,061 research outputs found
Modelling and measurement accuracy enhancement of flue gas flow using neural networks
This paper discusses the modeling of the flue gas flow in industrial ducts and stacks using artificial neural networks (ANN's). Based upon the individual velocity and other operating conditions, an ANN model has been developed for the measurement of the volume flow rate. The model has been validated by the experiment using a case-study power plant. The results have shown that the model can largely compensate for the nonrepresentativeness of a sampling location and, as a result, the measurement accuracy of the flue gas flow can be significantly improved
Continuous Multipartite Entangled State in Wigner Representation and the Violation of Zukowski-Brukner Inequality
We construct an explicit Wigner function for N-mode squeezed state. Based on
a previous observation that the Wigner function describes correlations in the
joint measurement of the phase-space displaced parity operator, we investigate
the non-locality of multipartite entangled state by the violation of
Zukowski-Brukner N-qubit Bell inequality. We find that quantum predictions for
such squeezed state violate these inequalities by an amount that grows with the
number N.Comment: 5 pages, rewritten version, accepted by Phys. Rev.
Magnetic field splitting of the spin-resonance in CeCoIn5
Neutron scattering in strong magnetic fields is used to show the
spin-resonance in superconducting CeCoIn5 (Tc=2.3 K) is a doublet. The
underdamped resonance (\hbar \Gamma=0.069 \pm 0.019 meV) Zeeman splits into two
modes at E_{\pm}=\hbar \Omega_{0}\pm g\mu_{B} \mu_{0}H with g=0.96 \pm 0.05. A
linear extrapolation of the lower peak reaches zero energy at 11.2 \pm 0.5 T,
near the critical field for the incommensurate "Q-phase" indicating that the
Q-phase is a bose condensate of spin excitons.Comment: 5 pages, 4 figure
Spin resonance in the d-wave superconductor CeCoIn5
Neutron scattering is used to probe antiferromagnetic spin fluctuations in
the d-wave heavy fermion superconductor CeCoIn (T=2.3 K).
Superconductivity develops from a state with slow (=0.3 0.15
meV) commensurate (=(1/2,1/2,1/2)) antiferromagnetic spin
fluctuations and nearly isotropic spin correlations. The characteristic
wavevector in CeCoIn is the same as CeIn but differs from the
incommensurate wavevector measured in antiferromagnetically ordered
CeRhIn. A sharp spin resonance ( meV) at
= 0.60 0.03 meV develops in the superconducting state removing spectral
weight from low-energy transfers. The presence of a resonance peak is
indicative of strong coupling between f-electron magnetism and
superconductivity and consistent with a d-wave gap order parameter satisfying
.Comment: (5 pages, 4 figures, to be published in Phys. Rev. Lett.
Metal-insulator (fermion-boson)-crossover origin of pseudogap phase of cuprates I: anomalous heat conductivity, insulator resistivity boundary, nonlinear entropy
Among all experimental observations of cuprate physics, the
metal-insulator-crossover (MIC), seen in the pseudogap (PG) region of the
temperature-doping phase diagram of copper-oxides under a strong magnetic
field, when the superconductivity is suppressed, is most likely the most
intriguing one. Since it was expected that the PG-normal state for these
materials, as for conventional superconductors, is conducting. This MIC,
revealed in such phenomena as heat conductivity downturn, anomalous Lorentz
ratio, insulator resistivity boundary, nonlinear entropy, resistivity
temperature upturn, insulating ground state, nematicity- and stripe-phases and
Fermi pockets, unambiguously indicates on the insulating normal state, from
which the high-temperature superconductivity (HTS) appears. In the present work
(article I), we discuss the MIC phenomena mentioned in the title of article.
The second work (article II) will be devoted to discussion of other listed
above MIC phenomena and also to interpretation of the recent observations in
the hidden magnetic order and scanning tunneling microscopy (STM) experiments
spin and charge fluctuations as the intra PG and HTS pair ones. We find that
all these MIC (called in the literature as non-Fermi liquid) phenomena can be
obtained within the Coulomb single boson and single fermion two liquid model,
which we recently developed, and the MIC is a crossover of single fermions into
those of single bosons. We show that this MIC originates from bosons of Coulomb
two liquid model and fermions, whose origin is these bosons. At an increase of
doping up to critical value or temperature up to PG boundary temperature, the
boson system undegoes bosonic insulator - bosonic metal - fermionic metal
transitions.Comment: 13 pages, 3 figure
A direct link between neutrinoless double beta decay and leptogenesis in a seesaw model with symmetry
We study how leptogenesis can be implemented in a seesaw model with
flavor symmetry, which leads to the neutrino tri-bimaximal mixing matrix and
degenerate right-handed (RH) neutrino spectrum. Introducing a tiny soft
symmetry breaking term in the RH neutrino mass matrix, we show that the
flavored resonant leptogenesis can be successfully realized, which can lower
the seesaw scale much so as to make it possible to probe in colliders. Even
though such a tiny soft breaking term is essential for leptogenesis, it does
not significantly affect the low energy observables. We also investigate how
the effective light neutrino mass associated with neutrinoless
double beta decay can be predicted along with the neutrino mass hierarchies by
imposing experimental data of low-energy observables. We find a direct link
between leptogenesis and neutrinoless double beta decay characterized by
through a high energy CP phase , which is correlated with
low energy Majorana CP phases. It is shown that our predictions of
for some fixed parameters of high energy physics can be constrained by the
current observation of baryon asymmetry.Comment: 9 pages, 6 figures, references added, accepted in Phy.Rev.
Domain growth and freezing on a triangular lattice
We have performed Monte Carlo simulations of domain growth at zero temperature of a lattice gas with nearest-neighbor repulsive interactions on a triangular lattice. Kawasaki dynamics were used with a fractional surface coverage of one-third. We studied both the case in which the second-nearest-neighbor interaction is attractive and the case in which it is zero. The effect of increasing the range of allowed hops from nearest neighbor to third nearest neighbor was investigated. We find that domain growth freezes in the case in which the second-nearest-neighbor interaction is attractive and only nearest-neighbor hops are allowed. Domain freezing is released when longer-range hops are allowed or when the second-nearest-neighbor interaction is zero. Allowing only nearest-neighbor hops, the growth exponent when there is no second-nearest-neighbor interaction is consistent with the Lifshitz-Slyozov theory. We conclude that the range of particle hops is an important parameter to consider when classifying growth kinetics
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