301 research outputs found
A KINETIC COMPARISON OF THE INSIDE SOCCER KICK BETWEEN HIGH PERFORMANCE PLAYER AND JUNIOR PLAYERS
Kinetic aspect of the inside soccer kick was investigated and comparison was made between those of a high performance player and junior players. One high performance player and five junior players volunteered to participate in this study. Their kicking motions were analyzed through three-dimensional cinematograpgic technique. Joints torques, generated at hip and knee joints, were computed by a three-link kinetic chain composed of thigh, shank, and foot. A marked difference was observed for the hip external rotation torque. All the junior players exhibited hip external rotation torque, and its magnitude was particularly dominant in the latter part of leg swing. Conversely, the magnitude of hip external rotation torque for the professional player was negligible. These results may help to explain differences in kicking techniques between the two levels of players
Temporal and Spatial Analyses of Spectral Indices of Nonthermal Emissions Derived from Hard X-Rays and Microwaves
We studied electron spectral indices of nonthermal emissions seen in hard
X-rays (HXRs) and in microwaves. We analyzed 12 flares observed by the Hard
X-ray Telescope aboard {\it Yohkoh}, Nobeyama Radio Polarimeters (NoRP), and
the Nobeyama Radioheliograph (NoRH), and compared the spectral indices derived
from total fluxes of hard X-rays and microwaves. Except for four events, which
have very soft HXR spectra suffering from the thermal component, these flares
show a gap between the electron spectral indices derived from
hard X-rays and those from microwaves
() of about 1.6. Furthermore, from
the start to the peak times of the HXR bursts, the time profiles of the HXR
spectral index evolve synchronously with those of the microwave
spectral index , keeping the constant gap. We also examined the
spatially resolved distribution of the microwave spectral index by using NoRH
data. The microwave spectral index tends to be larger, which
means a softer spectrum, at HXR footpoint sources with stronger magnetic field
than that at the loop tops. These results suggest that the electron spectra are
bent at around several hundreds of keV, and become harder at the higher energy
range that contributes the microwave gyrosynchrotron emission.Comment: 24 pages, 6 figures, accepted for publication in Ap
The OVAL experiment: A new experiment to measure vacuum magnetic birefringence using high repetition pulsed magnets
A new experiment to measure vacuum magnetic birefringence (VMB), the OVAL
experiment, is reported. We developed an original pulsed magnet that has a high
repetition rate and applies the strongest magnetic field among VMB experiments.
The vibration isolation design and feedback system enable the direct
combination of the magnet with a Fabry-P\'erot cavity. To ensure the searching
potential, a calibration measurement with dilute nitrogen gas and a prototype
search for vacuum magnetic birefringence are performed. Based on the results, a
strategy to observe vacuum magnetic birefringence is reported.Comment: 9 pages, 11 figure
The Building to the system of cooperation between schools and the related organizations : Through the efforts of “Sub Care System Meeting”
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