42,940 research outputs found
Query generation from multiple media examples
This paper exploits an unified media document representation called feature terms for query generation from multiple media examples, e.g. images. A feature term refers to a value interval of a media feature. A media document is therefore represented by a frequency vector about feature term appearance. This approach (1) facilitates feature accumulation from multiple examples; (2) enables the exploration of text-based retrieval models for multimedia retrieval. Three statistical criteria, minimised chi-squared, minimised AC/DC rate and maximised entropy, are proposed to extract feature terms from a given media document collection. Two textual ranking functions, KL divergence and a BM25-like retrieval model, are adapted to estimate media document relevance. Experiments on the Corel photo collection and the TRECVid 2006 collection show the effectiveness of feature term based query in image and video retrieval
General highlight detection in sport videos
Attention is a psychological measurement of human reflection against stimulus. We propose a general framework of highlight detection by comparing attention intensity during the watching of sports videos. Three steps are involved: adaptive selection on salient features, unified attention estimation and highlight identification. Adaptive selection computes feature correlation to decide an optimal set of salient features. Unified estimation combines these features by the technique of multi-resolution autoregressive (MAR) and thus creates a temporal curve of attention intensity. We rank the intensity of attention to discriminate boundaries of highlights. Such a framework alleviates semantic uncertainty around sport highlights and leads to an efficient and effective highlight detection. The advantages are as follows: (1) the capability of using data at coarse temporal resolutions; (2) the robustness against noise caused by modality asynchronism, perception uncertainty and feature mismatch; (3) the employment of Markovian constrains on content presentation, and (4) multi-resolution estimation on attention intensity, which enables the precise allocation of event boundaries
The branch processes of vortex filaments and Hopf Invariant Constraint on Scroll Wave
In this paper, by making use of Duan's topological current theory, the
evolution of the vortex filaments in excitable media is discussed in detail.
The vortex filaments are found generating or annihilating at the limit points
and encountering, splitting, or merging at the bifurcation points of a complex
function . It is also shown that the Hopf invariant of knotted
scroll wave filaments is preserved in the branch processes (splitting, merging,
or encountering) during the evolution of these knotted scroll wave filaments.
Furthermore, it also revealed that the "exclusion principle" in some chemical
media is just the special case of the Hopf invariant constraint, and during the
branch processes the "exclusion principle" is also protected by topology.Comment: 9 pages, 5 figure
Calculations on the Size Effects of Raman Intensities of Silicon Quantum Dots
Raman intensities of Si quantum dots (QDs) with up to 11,489 atoms (about 7.6
nm in diameter) for different scattering configurations are calculated. First,
phonon modes in these QDs, including all vibration frequencies and vibration
amplitudes, are calculated directly from the lattice dynamic matrix by using a
microscopic valence force field model combined with the group theory. Then the
Raman intensities of these quantum dots are calculated by using a
bond-polarizability approximation. The size effects of the Raman intensity in
these QDs are discussed in detail based on these calculations. The calculations
are compared with the available experimental observation. We are expecting that
our calculations can further stimulate more experimental measurements.Comment: 21 pages, 7 figure
Electromagnetically controlled multiferroic thermal diode
We propose an electromagnetically tunable thermal diode based on a two phase
multiferroics composite. Analytical and full numerical calculations for
prototypical heterojunction composed of Iron on Barium titanate in the
tetragonal phase demonstrate a strong heat rectification effect that can be
controlled externally by a moderate electric field. This finding is of an
importance for thermally based information processing and sensing and can also
be integrated in (spin)electronic circuits for heat management and recycling.Comment: Accepted in Phys. Rev.
Approximation of Random Slow Manifolds and Settling of Inertial Particles under Uncertainty
A method is provided for approximating random slow manifolds of a class of
slow-fast stochastic dynamical systems. Thus approximate, low dimensional,
reduced slow systems are obtained analytically in the case of sufficiently
large time scale separation. To illustrate this dimension reduction procedure,
the impact of random environmental fluctuations on the settling motion of
inertial particles in a cellular flow field is examined. It is found that noise
delays settling for some particles but enhances settling for others. A
deterministic stable manifold is an agent to facilitate this phenomenon.
Overall, noise appears to delay the settling in an averaged sense.Comment: 27 pages, 9 figure
LHC Constraints on a Higgs Partner from an Extended Color Sector
We discuss the properties and LHC phenomenology of a potentially discoverable
heavy scalar boson () that arises in the context of the renormalizable
coloron model; the model also contains a light scalar, , identifiable with
the 125 GeV state discovered by the LHC. These two scalar mass eigenstates are
admixtures of a weak doublet gauge eigenstate and a weak singlet gauge
eigenstate. A previous study set exclusion limits on the heavy scalar,
using the stability of the scalar potential, unitarity, electroweak precision
tests, LHC searches for the 125 GeV Higgs; it also briefly discussed the
TeV LHC searches for a heavy Higgs. In this work, we show how
the projected LHC sensitivity at TeV to the presence of a heavy
Higgs and to the detailed properties of the 125 GeV Higgs will further
constrain the properties of the new heavy scalar. Since the renormalizable
coloron model may contain spectator fermions to remove anomalies, we examine
several representative scenarios with different numbers of spectator fermions.
Our results are summarized in plots that overlay the current exclusion limits
on the boson with the projected sensitivity of the TeV LHC
to the new state. We find that the upcoming LHC searches should be sensitive to
an scalar of mass less than 1 TeV for essentially all of the model
parameter space in which the state differs from the Higgs boson of the SM.
More precisely, unless the mixing between the weak doublet and weak singlet
gauge-eigenstate scalars is zero, the 14 TeV LHC will be sensitive to the
presence of the non-standard heavy state that is characteristic of the
renormalizable coloron model.Comment: 13 pages, 22 embedded figure
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