18,559 research outputs found
Transductive Multi-View Zero-Shot Learning
(c) 2012. The copyright of this document resides with its authors.
It may be distributed unchanged freely in print or electronic forms
Learning Multimodal Latent Attributes
Abstract—The rapid development of social media sharing has created a huge demand for automatic media classification and annotation techniques. Attribute learning has emerged as a promising paradigm for bridging the semantic gap and addressing data sparsity via transferring attribute knowledge in object recognition and relatively simple action classification. In this paper, we address the task of attribute learning for understanding multimedia data with sparse and incomplete labels. In particular we focus on videos of social group activities, which are particularly challenging and topical examples of this task because of their multi-modal content and complex and unstructured nature relative to the density of annotations. To solve this problem, we (1) introduce a concept of semi-latent attribute space, expressing user-defined and latent attributes in a unified framework, and (2) propose a novel scalable probabilistic topic model for learning multi-modal semi-latent attributes, which dramatically reduces requirements for an exhaustive accurate attribute ontology and expensive annotation effort. We show that our framework is able to exploit latent attributes to outperform contemporary approaches for addressing a variety of realistic multimedia sparse data learning tasks including: multi-task learning, learning with label noise, N-shot transfer learning and importantly zero-shot learning
Dust-to-gas ratio, factor and CO-dark gas in the Galactic anticentre: an observational study
We investigate the correlation between extinction and H~{\sc i} and CO
emission at intermediate and high Galactic latitudes (|b|>10\degr) within the
footprint of the Xuyi Schmidt Telescope Photometric Survey of the Galactic
anticentre (XSTPS-GAC) on small and large scales. In Paper I (Chen et al.
2014), we present a three-dimensional dust extinction map within the footprint
of XSTPS-GAC, covering a sky area of over 6,000\,deg at a spatial angular
resolution of 6\,arcmin. In the current work, the map is combined with data
from gas tracers, including H~{\sc i} data from the Galactic Arecibo L-band
Feed Array H~{\sc i} survey and CO data from the Planck mission, to constrain
the values of dust-to-gas ratio and CO-to-
conversion factor for the entire GAC
footprint excluding the Galactic plane, as well as for selected star-forming
regions (such as the Orion, Taurus and Perseus clouds) and a region of diffuse
gas in the northern Galactic hemisphere. For the whole GAC footprint, we find
\, and \,. We have also
investigated the distribution of "CO-dark" gas (DG) within the footprint of GAC
and found a linear correlation between the DG column density and the -band
extinction: . The mass fraction of DG is found to be toward
the Galactic anticentre, which is respectively about 23 and 124 per cent of the
atomic and CO-traced molecular gas in the same region. This result is
consistent with the theoretical work of Papadopoulos et al. but much larger
than that expected in the cloud models by Wolfire et al.Comment: 11 pages, 7 figures, accepted for publication in MNRA
HST and LAMOST discover a dual active galactic nucleus in J0038+4128
We report the discovery of a kiloparsec-scale dual active galactic nucleus
(AGN) in J0038+4128. From the Hubble Space Telescope (HST) Wide Field Planetary
Camera (WFPC2) images, we find two optical nuclei with a projection separation
of 4.7 kpc (3.44 arcsec). The southern component (J0038+4128S) is
spectroscopically observed with the HST Goddard High Resolution Spectrograph in
the UV range and is found to be a Seyfert 1 galaxy with a broad Ly alpha
emission line. The northern component (J0038+4128N) is spectroscopically
observed during the Large Sky Area Multi-Object Fibre Spectroscopic Telescope
(also named the Guoshoujing Telescope) pilot survey in the optical range. The
observed line ratios as well as the consistency of redshift of the nucleus
emission lines and the host galaxy's absorption lines indicate that J0038+4128N
is a Seyfert 2 galaxy with narrow lines only. These results thus confirm that
J0038+4128 is a Seyfert 1-Seyfert 2 AGN pair. The HST WFPC2 F336W/U-band image
of J0038+4128 also reveals for the first time for a dual AGN system two pairs
of bi-symmetric arms, as are expected from the numerical simulations of such
system. Being one of a few confirmed kiloparsec-scale dual AGNs exhibiting a
clear morphological structure of the host galaxies, J0038+4128 provides an
unique opportunity to study the co-evolution of the host galaxies and their
central supermassive black holes undergoing a merging process.Comment: 6 pages, 4 figures, 2 tables, Accepted for publication in MNRAS
Letter
Demonstration of Temporal Distinguishability in a Four-Photon State and a Six-Photon State
An experiment is performed to demonstrate the temporal distinguishability of
a four-photon state and a six-photon state, both from parametric
down-conversion. The experiment is based on a multi-photon interference scheme
in a recent discovered NOON-state projection measurement. By measuring the
visibility of the interference dip, we can distinguish the various scenarios in
the temporal distribution of the pairs and thus quantitatively determine the
degree of temporal (in)distinguishability of a multi-photon state
In an Attempt to Introduce Long-range Interactions into Small-world Networks
Distinguishing the long-range bonds with the regular ones, the critical
temperature of the spin-lattice Guassian model built on two typical Small-world
Networks (SWNs) is studied. The results show much difference from the classical
case, and thus may induce some more accurate discussion on the critical
properties of the spin-lattice systems combined with the SWNs.Comment: 4 pages, 3 figures, 18 referenc
- …