2,368 research outputs found
信号分子に応じた変形機能を有する分子ロボットの開発
要約のみTohoku University野村慎一郎課
Oscillations in the G-type Giants
The precise radial-velocity measurements of 4 G-type giants, 11Com,
Hya, Tau, and Her were carried out. The short-term variations
with amplitudes, 1-7m/s and periods, 3-10 hours were detected. A period
analysis shows that the individual power distribution is in a Gaussian shape
and their peak frequencies () are in a good agreement with the
prediction by the scaling law. With using a pre-whitening procedure,
significant frequency peaks more than 3 are extracted for these
giants. From these peaks, we determined the large frequency separation by
constructing highest peak distribution of collapsed power spectrum, which is
also in good agreement with what the scaling law for the large separation
predicts. Echelle diagrams of oscillation frequency were created based on the
extracted large separations, which is very useful to clarify the properties of
oscillation modes. In these echelle diagrams, odd-even mode sequences are
clearly seen. Therefore, it is certain that in these G-type giants, non-radial
modes are detected in addition to radial mode. As a consequence, these
properties of oscillation modes are shown to follow what Dzymbowski et
al.(2001) and Dupret et al.(2009) theoretically predicted. Damping times for
these giants were estimated with the same method as that developed by Stello et
al.(2004). The relation of Q value (ratio of damping time to period) to the
period was discussed by adding the data of the other stars ranging from dwarfs
to giants.Comment: 28 pages, 16 figures, accepted for publication in PASJ 62, No.4, 201
CHARACTERISTICS OF JOINT TORQUES IN PERFORMING THE BASKET TO HANDSTAND ON PARALLEL BARS
The purpose of this study was to investigate characteristics of joint torques in performing the basket to handstand on parallel bars. Twenty-six male elite gymnasts were videotaped in the national championships. Two-dimensional motion analysis technique and inverse dynamics approach were used for calculating the kinematic and kinetic parameters. The shoulder and hip joint torques did not relate to the upward velocity, but significantly related to the downward and forward velocities in performing the basket to handstand. Development of the shoulder flexion torque should be as small as possible for the execution to use the greater swing velocity
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