4,062 research outputs found
HEAR: Hearing Enhanced Audio Response for Video-grounded Dialogue
Video-grounded Dialogue (VGD) aims to answer questions regarding a given
multi-modal input comprising video, audio, and dialogue history. Although there
have been numerous efforts in developing VGD systems to improve the quality of
their responses, existing systems are competent only to incorporate the
information in the video and text and tend to struggle in extracting the
necessary information from the audio when generating appropriate responses to
the question. The VGD system seems to be deaf, and thus, we coin this symptom
of current systems' ignoring audio data as a deaf response. To overcome the
deaf response problem, Hearing Enhanced Audio Response (HEAR) framework is
proposed to perform sensible listening by selectively attending to audio
whenever the question requires it. The HEAR framework enhances the accuracy and
audibility of VGD systems in a model-agnostic manner. HEAR is validated on VGD
datasets (i.e., AVSD@DSTC7 and AVSD@DSTC8) and shows effectiveness with various
VGD systems.Comment: EMNLP 2023, 14 pages, 13 figure
Formation of Warped Disks by Galactic Fly-by Encounters. I. Stellar Disks
Warped disks are almost ubiquitous among spiral galaxies. Here we revisit and
test the `fly-by scenario' of warp formation, in which impulsive encounters
between galaxies are responsible for warped disks. Based on N-body simulations,
we investigate the morphological and kinematical evolution of the stellar
component of disks when galaxies undergo fly-by interactions with adjacent dark
matter halos. We find that the so-called `S'-shaped warps can be excited by
fly-bys and sustained for even up to a few billion years, and that this
scenario provides a cohesive explanation for several key observations. We show
that disk warp properties are governed primarily by the following three
parameters; (1) the impact parameter, i.e., the minimum distance between two
halos, (2) the mass ratio between two halos, and (3) the incident angle of the
fly-by perturber. The warp angle is tied up with all three parameters, yet the
warp lifetime is particularly sensitive to the incident angle of the perturber.
Interestingly, the modeled S-shaped warps are often non-symmetric depending on
the incident angle. We speculate that the puzzling U- and L-shaped warps are
geometrically superimposed S-types produced by successive fly-bys with
different incident angles, including multiple interactions with a satellite on
a highly elongated orbit.Comment: 16 pages, 13 figures, 3 tables. Accepted for publication in Ap
Information-Theoretic Text Hallucination Reduction for Video-grounded Dialogue
Video-grounded Dialogue (VGD) aims to decode an answer sentence to a question
regarding a given video and dialogue context. Despite the recent success of
multi-modal reasoning to generate answer sentences, existing dialogue systems
still suffer from a text hallucination problem, which denotes indiscriminate
text-copying from input texts without an understanding of the question. This is
due to learning spurious correlations from the fact that answer sentences in
the dataset usually include the words of input texts, thus the VGD system
excessively relies on copying words from input texts by hoping those words to
overlap with ground-truth texts. Hence, we design Text Hallucination Mitigating
(THAM) framework, which incorporates Text Hallucination Regularization (THR)
loss derived from the proposed information-theoretic text hallucination
measurement approach. Applying THAM with current dialogue systems validates the
effectiveness on VGD benchmarks (i.e., AVSD@DSTC7 and AVSD@DSTC8) and shows
enhanced interpretability.Comment: 12 pages, Accepted in EMNLP 202
Simultaneous VLBI Astrometry of H2O and SiO Masers toward the Semiregular Variable R Crateris
We obtained, for the first time, astrometrically registered maps of the 22.2
GHz H2O and 42.8, 43.1, and 86.2 GHz SiO maser emission toward the semiregular
b-type variable (SRb) R Crateris, at three epochs (2015 May 21, and 2016
January 7 and 26) using the Korean Very-long-baseline Interferometry Network.
The SiO masers show a ring-like spatial structure, while the H2O maser shows a
very asymmetric one-side outflow structure, which is located at the southern
part of the ring-like SiO maser feature. We also found that the 86.2 GHz SiO
maser spots are distributed in an inner region, compared to those of the 43.1
GHz SiO maser, which is different from all previously known distributions of
the 86.2 GHz SiO masers in variable stars. The different distribution of the
86.2 GHz SiO maser seems to be related to the complex dynamics caused by the
overtone pulsation mode of the SRb R Crateris. Furthermore, we estimated the
position of the central star based on the ring fitting of the SiO masers, which
is essential for interpreting the morphology and kinematics of a circumstellar
envelope. The estimated stellar coordinate corresponds well to the position
measured by Gaia
- …