10,964 research outputs found
Effects of spatial noncommutativity on energy spectrum of a trapped Bose-Einstein condensate
In noncommutative space, we examine the problem of a noninteracting and
harmonically trapped Bose-Einstein condensate, and derive a simple analytic
expression for the effect of spatial noncommutativity on energy spectrum of the
condensate. It indicates that the ground-state energy incorporating the spatial
noncommutativity is reduced to a lower level, which depends upon the
noncommutativity parameter . The appeared gap between the
noncommutative space and commutative one for the ground-state level of the
condensate should be a signal of spatial noncommutativity.Comment: 7 pages; revtex
Building a Large Scale Dataset for Image Emotion Recognition: The Fine Print and The Benchmark
Psychological research results have confirmed that people can have different
emotional reactions to different visual stimuli. Several papers have been
published on the problem of visual emotion analysis. In particular, attempts
have been made to analyze and predict people's emotional reaction towards
images. To this end, different kinds of hand-tuned features are proposed. The
results reported on several carefully selected and labeled small image data
sets have confirmed the promise of such features. While the recent successes of
many computer vision related tasks are due to the adoption of Convolutional
Neural Networks (CNNs), visual emotion analysis has not achieved the same level
of success. This may be primarily due to the unavailability of confidently
labeled and relatively large image data sets for visual emotion analysis. In
this work, we introduce a new data set, which started from 3+ million weakly
labeled images of different emotions and ended up 30 times as large as the
current largest publicly available visual emotion data set. We hope that this
data set encourages further research on visual emotion analysis. We also
perform extensive benchmarking analyses on this large data set using the state
of the art methods including CNNs.Comment: 7 pages, 7 figures, AAAI 201
Coherent Destruction of Tunneling and Dark Floquet State
We study a system of three coherently coupled states, where one state is
shifted periodically against the other two. We discover such a system possesses
a dark Floquet state at zero quasienergy and always with negligible population
at the intermediate state. This dark Floquet state manifests itself dynamically
in terms of the suppression of inter-state tunneling, a phenomenon known as
coherent destruction of tunneling. We suggest to call it dark coherent
destruction of tunneling (DCDT). At high frequency limit for the periodic
driving, this Floquet state reduces to the well-known dark state widely used
for STIRAP. Our results can be generalized to systems with more states and can
be verified with easily implemented experiments within current technologies.Comment: 5 pages, 3 figure
Robust Image Sentiment Analysis Using Progressively Trained and Domain Transferred Deep Networks
Sentiment analysis of online user generated content is important for many
social media analytics tasks. Researchers have largely relied on textual
sentiment analysis to develop systems to predict political elections, measure
economic indicators, and so on. Recently, social media users are increasingly
using images and videos to express their opinions and share their experiences.
Sentiment analysis of such large scale visual content can help better extract
user sentiments toward events or topics, such as those in image tweets, so that
prediction of sentiment from visual content is complementary to textual
sentiment analysis. Motivated by the needs in leveraging large scale yet noisy
training data to solve the extremely challenging problem of image sentiment
analysis, we employ Convolutional Neural Networks (CNN). We first design a
suitable CNN architecture for image sentiment analysis. We obtain half a
million training samples by using a baseline sentiment algorithm to label
Flickr images. To make use of such noisy machine labeled data, we employ a
progressive strategy to fine-tune the deep network. Furthermore, we improve the
performance on Twitter images by inducing domain transfer with a small number
of manually labeled Twitter images. We have conducted extensive experiments on
manually labeled Twitter images. The results show that the proposed CNN can
achieve better performance in image sentiment analysis than competing
algorithms.Comment: 9 pages, 5 figures, AAAI 201
Heavy and light flavor jet quenching at RHIC and LHC energies
The Linear Boltzmann Transport (LBT) model coupled to hydrodynamical
background is extended to include transport of both light partons and heavy
quarks through the quark-gluon plasma (QGP) in high-energy heavy-ion
collisions. The LBT model includes both elastic and inelastic
medium-interaction of both primary jet shower partons and thermal recoil
partons within perturbative QCD (pQCD). It is shown to simultaneously describe
the experimental data on heavy and light flavor hadron suppression in
high-energy heavy-ion collisions for different centralities at RHIC and LHC
energies. More detailed investigations within the LBT model illustrate the
importance of both initial parton spectra and the shapes of fragmentation
functions on the difference between the nuclear modifications of light and
heavy flavor hadrons. The dependence of the jet quenching parameter
on medium temperature and jet flavor is quantitatively extracted.Comment: 6 pages, 6 figure
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