1,244 research outputs found
Low-Light Enhancement in the Frequency Domain
Decreased visibility, intensive noise, and biased color are the common
problems existing in low-light images. These visual disturbances further reduce
the performance of high-level vision tasks, such as object detection, and
tracking. To address this issue, some image enhancement methods have been
proposed to increase the image contrast. However, most of them are implemented
only in the spatial domain, which can be severely influenced by noise signals
while enhancing. Hence, in this work, we propose a novel residual recurrent
multi-wavelet convolutional neural network R2-MWCNN learned in the frequency
domain that can simultaneously increase the image contrast and reduce noise
signals well. This end-to-end trainable network utilizes a multi-level discrete
wavelet transform to divide input feature maps into distinct frequencies,
resulting in a better denoise impact. A channel-wise loss function is proposed
to correct the color distortion for more realistic results. Extensive
experiments demonstrate that our proposed R2-MWCNN outperforms the
state-of-the-art methods quantitively and qualitatively.Comment: 8 page
A Comparative Study on Regularization Strategies for Embedding-based Neural Networks
This paper aims to compare different regularization strategies to address a
common phenomenon, severe overfitting, in embedding-based neural networks for
NLP. We chose two widely studied neural models and tasks as our testbed. We
tried several frequently applied or newly proposed regularization strategies,
including penalizing weights (embeddings excluded), penalizing embeddings,
re-embedding words, and dropout. We also emphasized on incremental
hyperparameter tuning, and combining different regularizations. The results
provide a picture on tuning hyperparameters for neural NLP models.Comment: EMNLP '1
Classifying Relations via Long Short Term Memory Networks along Shortest Dependency Path
Relation classification is an important research arena in the field of
natural language processing (NLP). In this paper, we present SDP-LSTM, a novel
neural network to classify the relation of two entities in a sentence. Our
neural architecture leverages the shortest dependency path (SDP) between two
entities; multichannel recurrent neural networks, with long short term memory
(LSTM) units, pick up heterogeneous information along the SDP. Our proposed
model has several distinct features: (1) The shortest dependency paths retain
most relevant information (to relation classification), while eliminating
irrelevant words in the sentence. (2) The multichannel LSTM networks allow
effective information integration from heterogeneous sources over the
dependency paths. (3) A customized dropout strategy regularizes the neural
network to alleviate overfitting. We test our model on the SemEval 2010
relation classification task, and achieve an -score of 83.7\%, higher than
competing methods in the literature.Comment: EMNLP '1
Full-frame data reduction method: a data mining tool to detect the potential variations in optical photometry
A Synchronous Photometry Data Extraction (SPDE) program, performing
indiscriminate monitors of all stars appearing at the same field of view of
astronomical image, is developed by integrating several Astropy affiliated
packages to make full use of time series observed by the traditional
small/medium aperture ground-based telescope. The complete full-frame stellar
photometry data reductions implemented for the two time series of cataclysmic
variables: RX J2102.0+3359 and Paloma J0524+4244 produce 363 and 641 optimal
light curves, respectively. A cross-identification with the SIMBAD finds 23
known stars, of which 16 red giant-/horizontal-branch stars, 2 W UMa-type
eclipsing variables, 2 program stars, a X-ray source and 2 Asteroid
Terrestrial-impact Last Alert System variables. Based on the data productions
of the SPDE program, a followup Light Curve Analysis (LCA) program identifies
32 potential variable light curves, of which 18 are from the time series of RX
J2102.0+3359, and 14 are from that of Paloma J0524+4244. They are preliminarily
separated into periodical, transient, and peculiar types. By querying for the
58 VizieR online data catalogs, their physical parameters and multi-band
brightness spanning from X-ray to radio are compiled for future analysis.Comment: 35pages, 8 figures, accepted by RA
Building Program Vector Representations for Deep Learning
Deep learning has made significant breakthroughs in various fields of
artificial intelligence. Advantages of deep learning include the ability to
capture highly complicated features, weak involvement of human engineering,
etc. However, it is still virtually impossible to use deep learning to analyze
programs since deep architectures cannot be trained effectively with pure back
propagation. In this pioneering paper, we propose the "coding criterion" to
build program vector representations, which are the premise of deep learning
for program analysis. Our representation learning approach directly makes deep
learning a reality in this new field. We evaluate the learned vector
representations both qualitatively and quantitatively. We conclude, based on
the experiments, the coding criterion is successful in building program
representations. To evaluate whether deep learning is beneficial for program
analysis, we feed the representations to deep neural networks, and achieve
higher accuracy in the program classification task than "shallow" methods, such
as logistic regression and the support vector machine. This result confirms the
feasibility of deep learning to analyze programs. It also gives primary
evidence of its success in this new field. We believe deep learning will become
an outstanding technique for program analysis in the near future.Comment: This paper was submitted to ICSE'1
Rigid vortices in MgB2
Magnetic relaxation of high-pressure synthesized MgB bulks with different
thickness is investigated. It is found that the superconducting dia-magnetic
moment depends on time in a logarithmic way; the flux-creep activation energy
decreases linearly with the current density (as expected by Kim-Anderson
model); and the activation energy increases linearly with the thickness of
sample when it is thinner than about 1 mm. These features suggest that the
vortices in the MgB are rather rigid, and the pinning and creep can be well
described by Kim-Anderson model.Comment: Typo corrected & reference adde
Shadow thermodynamics of the Hayward-AdS black hole
In this paper, the phase structure of the Hayward-AdS black hole (BH) is
studied using shadow formalism. It has been found that the shadow radius is a
monotonic function of the horizon radius and can therefore play an equivalent
role to the horizon radius in characterizing the thermodynamics of Hayward-AdS
BH. The thermodynamic phase transition (PT) of the Hayward-AdS BH is
investigated with the shadow radius. It is shown that as the magnetic charge
increases, the shadow radius becomes larger, while the coexistence temperature
becomes lower. The thermal profile of the Hayward-AdS BH is established by
combining the temperature diagram and the shadow cast diagram, which shows that
for a fixed magnetic charge, the temperature of the Hayward-AdS BH increases
with the pressure while the region of the thermal profile decreases with the
pressure. In particular, the temperature of the Hayward-AdS BH follows an
N-type change trend when it is smaller than the critical temperature. This
imply that the BH shadow may be used to investigate the thermodynamics of the
Hayward-AdS BH.Comment: 14 pages, 6 figure
Experimental Test of Tracking the King Problem
In quantum theory, the retrodiction problem is not as clear as its classical
counterpart because of the uncertainty principle of quantum mechanics. In
classical physics, the measurement outcomes of the present state can be used
directly for predicting the future events and inferring the past events which
is known as retrodiction. However, as a probabilistic theory,
quantum-mechanical retrodiction is a nontrivial problem that has been
investigated for a long time, of which the Mean King Problem is one of the most
extensively studied issues. Here, we present the first experimental test of a
variant of the Mean King Problem, which has a more stringent regulation and is
termed "Tracking the King". We demonstrate that Alice, by harnessing the shared
entanglement and controlled-not gate, can successfully retrodict the choice of
King's measurement without knowing any measurement outcome. Our results also
provide a counterintuitive quantum communication to deliver information hidden
in the choice of measurement.Comment: 16 pages, 5 figures, 2 table
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