1,122 research outputs found
Stellar Parameters and Elemental Abundances of Late-G Giants
The properties of 322 intermediate-mass late-G giants (comprising 10
planet-host stars) selected as the targets of Okayama Planet Search Program,
many of which are red-clump giants, were comprehensively investigated by
establishing their various stellar parameters (atmospheric parameters including
turbulent velocity fields, metallicity, luminosity, mass, age, projected
rotational velocity, etc.), and their photospheric chemical abundances for 17
elements, in order to study their mutual dependence, connection with the
existence of planets, and possible evolution-related characteristics. The
metallicity distribution of planet-host giants was found to be almost the same
as that of non-planet-host giants, making marked contrast to the case of
planet-host dwarfs tending to be metal-rich. Generally, the metallicities of
these comparatively young (typical age of ~10^9 yr) giants tend to be somewhat
lower than those of dwarfs at the same age, and super-metal-rich ([Fe/H] > 0.2)
giants appear to be lacking. Apparent correlations were found between the
abundances of C, O, and Na, suggesting that the surface compositions of these
elements have undergone appreciable changes due to dredge-up of H-burning
products by evolution-induced deep envelope mixing which becomes more efficient
for higher-mass stars.Comment: Accepted for publication in PASJ (21 pages, 15 figures) (wrong URL of
e-tables in Ver.1 has been corrected in Ver.2
Fast Multi-frame Stereo Scene Flow with Motion Segmentation
We propose a new multi-frame method for efficiently computing scene flow
(dense depth and optical flow) and camera ego-motion for a dynamic scene
observed from a moving stereo camera rig. Our technique also segments out
moving objects from the rigid scene. In our method, we first estimate the
disparity map and the 6-DOF camera motion using stereo matching and visual
odometry. We then identify regions inconsistent with the estimated camera
motion and compute per-pixel optical flow only at these regions. This flow
proposal is fused with the camera motion-based flow proposal using fusion moves
to obtain the final optical flow and motion segmentation. This unified
framework benefits all four tasks - stereo, optical flow, visual odometry and
motion segmentation leading to overall higher accuracy and efficiency. Our
method is currently ranked third on the KITTI 2015 scene flow benchmark.
Furthermore, our CPU implementation runs in 2-3 seconds per frame which is 1-3
orders of magnitude faster than the top six methods. We also report a thorough
evaluation on challenging Sintel sequences with fast camera and object motion,
where our method consistently outperforms OSF [Menze and Geiger, 2015], which
is currently ranked second on the KITTI benchmark.Comment: 15 pages. To appear at IEEE Conference on Computer Vision and Pattern
Recognition (CVPR 2017). Our results were submitted to KITTI 2015 Stereo
Scene Flow Benchmark in November 201
Future Person Localization in First-Person Videos
We present a new task that predicts future locations of people observed in
first-person videos. Consider a first-person video stream continuously recorded
by a wearable camera. Given a short clip of a person that is extracted from the
complete stream, we aim to predict that person's location in future frames. To
facilitate this future person localization ability, we make the following three
key observations: a) First-person videos typically involve significant
ego-motion which greatly affects the location of the target person in future
frames; b) Scales of the target person act as a salient cue to estimate a
perspective effect in first-person videos; c) First-person videos often capture
people up-close, making it easier to leverage target poses (e.g., where they
look) for predicting their future locations. We incorporate these three
observations into a prediction framework with a multi-stream
convolution-deconvolution architecture. Experimental results reveal our method
to be effective on our new dataset as well as on a public social interaction
dataset.Comment: Accepted to CVPR 201
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