36,314 research outputs found
SLIC Based Digital Image Enlargement
Low resolution image enhancement is a classical computer vision problem.
Selecting the best method to reconstruct an image to a higher resolution with
the limited data available in the low-resolution image is quite a challenge. A
major drawback from the existing enlargement techniques is the introduction of
color bleeding while interpolating pixels over the edges that separate distinct
colors in an image. The color bleeding causes to accentuate the edges with new
colors as a result of blending multiple colors over adjacent regions. This
paper proposes a novel approach to mitigate the color bleeding by segmenting
the homogeneous color regions of the image using Simple Linear Iterative
Clustering (SLIC) and applying a higher order interpolation technique
separately on the isolated segments. The interpolation at the boundaries of
each of the isolated segments is handled by using a morphological operation.
The approach is evaluated by comparing against several frequently used image
enlargement methods such as bilinear and bicubic interpolation by means of Peak
Signal-to-Noise-Ratio (PSNR) value. The results obtained exhibit that the
proposed method outperforms the baseline methods by means of PSNR and also
mitigates the color bleeding at the edges which improves the overall
appearance.Comment: 6 page
Meson decay in the Fock-Tani Formalism
The Fock-Tani formalism is a first principle method to obtain effective
interactions from microscopic Hamiltonians. Usually this formalism was applied
to scattering, here we introduced it to calculate partial decay widths for
mesons.Comment: Presented at HADRON05 XI. "International Conference on Hadron
Spectroscopy" Rio de Janeiro, Brazil, August 21 to 26, 200
Glueball-glueball scattering in a constituent gluon model
In this work we use a mapping technique to derive in the context of a
constituent gluon model an effective Hamiltonian that involves explicit gluon
degrees of freedom. We study glueballs with two gluons using the Fock-Tani
formalism. In the present work we consider two possibilities for : (i)
as a pure and calculate, in the context of a quark interchange
picture, the cross-section; (ii) as a glueball where a new calculation for this
cross-section is made, in the context of the constituent gluon model, with
gluon interchange.Comment: Proceedings of the International Workshop IX Hadron Physics and VII
Relativistic Aspects of Nuclear Physics (HADRON-RANP 2004
Sound and complete axiomatizations of coalgebraic language equivalence
Coalgebras provide a uniform framework to study dynamical systems, including
several types of automata. In this paper, we make use of the coalgebraic view
on systems to investigate, in a uniform way, under which conditions calculi
that are sound and complete with respect to behavioral equivalence can be
extended to a coarser coalgebraic language equivalence, which arises from a
generalised powerset construction that determinises coalgebras. We show that
soundness and completeness are established by proving that expressions modulo
axioms of a calculus form the rational fixpoint of the given type functor. Our
main result is that the rational fixpoint of the functor , where is a
monad describing the branching of the systems (e.g. non-determinism, weights,
probability etc.), has as a quotient the rational fixpoint of the
"determinised" type functor , a lifting of to the category of
-algebras. We apply our framework to the concrete example of weighted
automata, for which we present a new sound and complete calculus for weighted
language equivalence. As a special case, we obtain non-deterministic automata,
where we recover Rabinovich's sound and complete calculus for language
equivalence.Comment: Corrected version of published journal articl
Predicted defect induced vortex core switching in thin magnetic nanodisks
We investigate the influence of artificial defects (small holes) inserted
into magnetic nanodisks on the vortex core dynamics. One and two holes
(antidots) are considered. In general, the core falls into the hole but, in
particular, we would like to remark an interesting phenomenon not yet observed,
which is the vortex core switching induced by the vortex-hole interactions. It
occurs for the case with only one hole and for very special conditions
involving the hole size and position as well as the disk size. Any small
deformation in the disk geometry such as the presence of a second antidot
changes completely the vortex dynamics and the vortex core eventually falls
into one of the defects. After trapped, the vortex center still oscillates with
a very high frequency and small amplitude around the defect center.Comment: 11pages, Revtex format, 17 figure
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