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, $\zeta$ Hya, $\epsilon$ Tau, and $\eta$ 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 ($\nu_{max}$) are in a good agreement with the prediction by the scaling law. With using a pre-whitening procedure, significant frequency peaks more than 3 $\sigma$ 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