Takao Nakagawa

The far-Infrared [CII] 158μm line is the dominant coolant of neutral intersterllar gas. We made survey observations of the [CII] line with a dedicated system called BICE (Balloon-borne Infrared Carbon Explorer). We made two successful balloon campaigns : one to the United States, and the other to Australia. We observed various kinds of objects, including the Galactic plane (255°≲l≲78°, |b|≲3°), the Cygnus-X region, the ρ Ophiuchi dark cloud, and the Large Magellanic Cloud. The observational resulsts are briefly disccused.

One of the difficult problems in the study of the constitutive equation for cyclic plasticity is the prediction of ratchetting behavior which is induced by the superposition of a cyclic secondary load to a constant primary load in the biaxial case, or by the mean stress in a uniaxial case. This paper shows the constitutive equation in which the memorization of the back stress was considered for ratchetting behavior, especially for biaxial ratchetting behavior. To verify the applicability of the constitutive equation to ratchetting behavior, biaxial ratchetting tests were carried out using type 304stainless steel at room temperature. As a result, it was found that the simulations based on the constitutive equation had good agreement with the tests.

An accurate attitude-control system of a mirror has been developped for a balloon-borne infrared interferometer. This system controls the mirror in arbitrary attitudes and achieves an accuracy of less than 0.2 arcsec. The drive mechanism and the attitude sensor were newly developped for this system. The components described in this paper, such as the actuator and the sensor as well as the overall controll system can be used in balloon environment.