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Automatic parsing of sports videos with grammars
Motivated by the analogies between languages and sports videos, we introduce a novel
approach for video parsing with grammars. It utilizes compiler techniques for integrating both semantic
annotation and syntactic analysis to generate a semantic index of events and a table of content for a given
sports video. The video sequence is first segmented and annotated by event detection with domain
knowledge. A grammar-based parser is then used to identify the structure of the video content.
Meanwhile, facilities for error handling are introduced which are particularly useful when the results of
automatic parsing need to be adjusted. As a case study, we have developed a system for video parsing in
the particular domain of TV diving programs. Experimental results indicate the proposed approach is
effectiv
Quantum entangled ground states of two spinor Bose-Einstein condensates
We revisit in detail the non-mean-field ground-state phase diagram for a
binary mixture of spin-1 Bose-Einstein condensates including quantum
fluctuations. The non-commuting terms in the spin-dependent Hamiltonian under
single spatial mode approximation make it difficult to obtain exact
eigenstates. Utilizing the spin z-component conservation and the total spin
angular momentum conservation, we numerically derive the information of the
building blocks and evaluate von Neumann entropy to quantify the ground states.
The mean-field phase boundaries are found to remain largely intact, yet the
ground states show fragmented and entangled behaviors within large parameter
spaces of interspecies spin-exchange and singlet-pairing interactions.Comment: 7 pages, 5 figure
From p-branes to Cosmology
We study the relationship between static p-brane solitons and cosmological
solutions of string theory or M-theory. We discuss two different ways in which
extremal p-branes can be generalised to non-extremal ones, and show how wide
classes of recently discussed cosmological models can be mapped into
non-extremal p-brane solutions of one of these two kinds. We also extend
previous discussions of cosmological solutions to include some that make use of
cosmological-type terms in the effective action that can arise from the
generalised dimensional reduction of string theory or M-theory.Comment: Latex, 24 pages, no figur
General Kerr-NUT-AdS Metrics in All Dimensions
The Kerr-AdS metric in dimension D has cohomogeneity [D/2]; the metric
components depend on the radial coordinate r and [D/2] latitude variables \mu_i
that are subject to the constraint \sum_i \mu_i^2=1. We find a coordinate
reparameterisation in which the \mu_i variables are replaced by [D/2]-1
unconstrained coordinates y_\alpha, and having the remarkable property that the
Kerr-AdS metric becomes diagonal in the coordinate differentials dy_\alpha. The
coordinates r and y_\alpha now appear in a very symmetrical way in the metric,
leading to an immediate generalisation in which we can introduce [D/2]-1 NUT
parameters. We find that (D-5)/2 are non-trivial in odd dimensions, whilst
(D-2)/2 are non-trivial in even dimensions. This gives the most general
Kerr-NUT-AdS metric in dimensions. We find that in all dimensions D\ge4
there exist discrete symmetries that involve inverting a rotation parameter
through the AdS radius. These symmetries imply that Kerr-NUT-AdS metrics with
over-rotating parameters are equivalent to under-rotating metrics. We also
consider the BPS limit of the Kerr-NUT-AdS metrics, and thereby obtain, in odd
dimensions and after Euclideanisation, new families of Einstein-Sasaki metrics.Comment: Latex, 24 pages, minor typos correcte
Lambda and Anti-Lambda Hypernuclei in Relativistic Mean-field Theory
Several aspects about -hypernuclei in the relativistic mean field
theory, including the effective -nucleon coupling strengths based on
the successful effective nucleon-nucleon interaction PK1, hypernuclear magnetic
moment and -hypernuclei, have been presented. The effect of tensor
coupling in -hypernuclei and the impurity effect of to
nuclear structure have been discussed in detail.Comment: 8 pages, 2 figures, Proceedings of the Sendai International Symposium
"Strangeness in Nuclear and Hadronic Systems SENDAI08
Yang-Mills-Chern-Simons Supergravity
N=(1,0) supergravity in six dimensions admits AdS_3\times S^3 as a vacuum
solution. We extend our recent results presented in hep-th/0212323, by
obtaining the complete N=4 Yang-Mills-Chern-Simons supergravity in D=3, up to
quartic fermion terms, by S^3 group manifold reduction of the six dimensional
theory. The SU(2) gauge fields have Yang-Mills kinetic terms as well as
topological Chern-Simons mass terms. There is in addition a triplet of matter
vectors. After diagonalisation, these fields describe two triplets of
topologically-massive vector fields of opposite helicities. The model also
contains six scalars, described by a GL(3,R)/SO(3) sigma model. It provides the
first example of a three-dimensional gauged supergravity that can obtained by a
consistent reduction of string-theory or M-theory and that admits AdS_3 as a
vacuum solution. There are unusual features in the reduction from
six-dimensional supergravity, owing to the self-duality condition on the 3-form
field. The structure of the full equations of motion in N=(1,0) supergravity in
D=6 is also elucidated, and the role of the self-dual field strength as torsion
is exhibited.Comment: Latex, 22 pages, hep-th number correcte
Gluon Fusion induced Zg and Zgg Productions in the Standard Model at the LHC
We report calculations of the gluon induced Zg and Zgg productions in the
Standard Model at the LHC operating at both 7 TeV and 14 TeV collision energy.
We present total cross sections and differential distributions of the processes
and compare them with the leading and next-to-leading order QCD pp -> Z+1 jet,
Z+2 jets results. Our results show that the gluon induced Zg and Zgg
productions contribute to pp -> Z+1 jet, Z+2 jets at 1% level.Comment: 8 pages, 5 figure
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