59,576 research outputs found
PDMS/PVA composite ferroelectret for improved energy harvesting performance
This paper address the PDMS ferroelectret discharge issue for improved long- term energy harvesting performance. The PDMS/PVA ferroelectret is fabricated using a 3D-printed plastic mould technology and a functional PVA composite layer is introduced. The PDMS/PVA composite ferroelectret achieved 80% piezoelectric coefficient d33 remaining, compared with 40% without the proposed layer over 72 hours. Further, the retained percentage of output voltage is about 73% over 72 hours
Numerical simulations of negative-index refraction in wedge-shaped metamaterials
A wedge-shaped structure made of split-ring resonators (SRR) and wires is
numerically simulated to evaluate its refraction behavior. Four frequency
bands, namely, the stop band, left-handed band, ultralow-index band, and
positive-index band, are distinguished according to the refracted field
distributions. Negative phase velocity inside the wedge is demonstrated in the
left-handed band and the Snell's law is conformed in terms of its refraction
behaviors in different frequency bands. Our results confirmed that negative
index of refraction indeed exists in such a composite metamaterial and also
provided a convincing support to the results of previous Snell's law
experiments.Comment: 18 pages, 6 figure
Heavy Pentaquarks
We construct the spin-flavor wave functions of the possible heavy pentaquarks
containing an anti-charm or anti-bottom quark using various clustered quark
models. Then we estimate the masses and magnetic moments of the or heavy pentaquarks. We emphasize the difference in the
predictions of these models. Future experimental searches at BESIII, CLEOc,
BELLE, and LEP may find these interesting states
Pentaquark Magnetic Moments In Different Models
We calculate the magnetic moments of the pentaquark states from different
models and compare our results with predictions of other groups.Comment: 17 pages, no figur
Controlling chaos in a chaotic neural network
The chaotic neural network constructed with chaotic neuron shows the associative memory function, but its memory searching process cannot be stabilized in a stored state because of the chaotic motion of the network. In this paper, a pinning control method focused on the chaotic neural network is proposed. The computer simulation proves that the chaos in the chaotic neural network can be controlled with this method and the states of the network can converge in one of its stored patterns if the control strength and the pinning density are chosen suitable. It is found that in general the threshold of the control strength of a controlled network is smaller at higher pinned density and the chaos of the chaotic neural network can be controlled more easily if the pinning control is added to the variant neurons between the initial pattern and the target pattern
Magnetic Moments of Pentaquarks
If the of and pentaquarks is really found to
be by future experiments, they will be accompanied by
partners in some models. It is reasonable to expect that
these states will also be discovered in the near future with
the current intensive experimental and theoretical efforts. We estimate
pentaquark magnetic moments using different models.Comment: 13 page
A remark on the inversion of the magnification bias in the quasar-galaxy associations
We present an alternative but intuitive method of obtaining the true or intrinsic quasar luminosity function through the observed one in the framework of gravitational lensing. Such a so-called inversion of the magnification bias can be straightforwardly performed by means of the Mellin transformation instead of other complex methods. Application of our approach to the well-known form of the observed quasar luminosity function identifies the previous results in literature
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