917 research outputs found
The Chemical Compositions of Very Metal-Poor Stars HD 122563 and HD 140283; A View From the Infrared
From high resolution (R = 45,000), high signal-to-noise (S/N > 400) spectra
gathered with the Immersion Grating Infrared Spectrograph (IGRINS) in the H and
K photometric bands, we have derived elemental abundances of two bright,
well-known metal-poor halo stars: the red giant HD 122563 and the subgiant HD
140283. Since these stars have metallicities approaching [Fe/H] = -3, their
absorption features are generally very weak. Neutral-species lines of Mg, Si, S
and Ca are detectable, as well as those of the light odd-Z elements Na and Al.
The derived IR-based abundances agree with those obtained from
optical-wavelength spectra. For Mg and Si the abundances from the infrared
transitions are improvements to those derived from shorter wavelength data.
Many useful OH and CO lines can be detected in the IGRINS HD 122563 spectrum,
from which derived O and C abundances are consistent to those obtained from the
traditional [O I] and CH features. IGRINS high resolutions H- and K-band
spectroscopy offers promising ways to determine more reliable abundances for
additional metal-poor stars whose optical features are either not detectable,
or too weak, or are based on lines with analytical difficulties.Comment: Accepted for publication in ApJ (28 pages, 4 tables, 6 figures
Transfer Path Analysis of Output Noise Using Multi- dimensional Spectral Analysis Method For Vacuum Cleaner
ABSTRACT Noise reduction of vacuum cleaner is important, according as estimating quality of product. To reduce noise of vacuum cleaner, we need analysis of correct noise source and contribution grasping about Identified noise sources' output noise. Because noise sources' correlation exists in vacuum cleaner that is small and complicated system, and analysis is not easy. In this case, we need to apply Multi-dimensional spectral analysis (MDSA) method that can remove correlation among noise sources and grasp pure contribution degree of noise sources. In this study, we analyze transfer path analysis between output noise and input noise that measured in inside/outside of vacuum cleaner
GAIT ASYMMETRY IN CHILDREN WITH DOWN SYNDROME
It has been reported that approximately 80% of children with Down syndrome (OS) exhibit gait problems (Matteo, 2002), characterized by flat-footed contact with no heel-strike, excessive abduction of the leg in the swing phase, and abnormal knee and hip f1exions throughout the gait cycle (Parker et aI., 1986). Due to muscle hypotonia, muscle weakness, !igamentous laXity, and other orthopedic abnormalities, different gait characteristics exist. The purpose of this study was to investigate the gait (walking and running) asymmetry in children with OS
THE EFFECT OF 12-WEEK STRENGTH TRAINING ON GAIT CHARACTERISTICS IN ADOLESCENT WITH DOWN SYNDROME: A SINGLE CASE STUDY
It has been reported that approximately 80% of individuals with Down syndrome (DS) exhibit abnormal gait characteristics. They are exhibited by flat-footed contact with no heel-strike, excessive abduction of the leg in the swing phase, and abnormal knee and hip flexion throughout the gait cycle (Matteo, 2002). The purpose of this study was to examine the influence of a 12-week strength training program on the gait characteristics during walking by an adolescent with DS
High-resolution near-IR Spectral mapping with H and [Fe II] lines of Multiple Outflows around LkH 234
We present a high-resolution, near-IR spectroscopic study of multiple
outflows in the LkH 234 star formation region using the Immersion
GRating INfrared Spectrometer (IGRINS). Spectral mapping over the blueshifted
emission of HH 167 allowed us to distinguish at least three separate, spatially
overlapped, outflows in H and [Fe II] emission. We show that the H
emission represents not a single jet, but complex multiple outflows driven by
three known embedded sources: MM1, VLA 2, and VLA 3. There is a redshifted
H outflow at a low velocity, \VLSR 50 {\kms}, with respect to
the systemic velocity of \VLSR 11.5 {\kms}, that coincides with the
HO masers seen in earlier radio observations two arcseconds southwest of
VLA 2. We found that the previously detected [Fe II] jet with \VLSR
100 {\kms} driven by VLA 3B is also detected in H emission, and confirm
that this jet has a position angle about 240. Spectra of the
redshifted knots at 14\arcsec65\arcsec northeast of LkH 234 are
presented for the first time. These spectra also provide clues to the existence
of multiple outflows. We detected high-velocity (50120 {\kms}) H gas
in the multiple outflows around LkH 234. Since these gases move at
speeds well over the dissociation velocity ( 40 {\kms}), the emission must
originate from the jet itself rather than H gas in the ambient medium.
Also, position-velocity diagrams and excitation diagram indicate that emission
from knot C in HH 167 come from two different phenomena, shocks and
photodissociation.Comment: 32 pages, 12 figures, 2 tables, Accepted for publication in the
Astrophysical Journa
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