As a governmentally approved domestic entity for Space Situational Awareness, Korea Astronomy and Space Science Institute (KASI) is developing and operating an optical telescopes system, Optical Wide-field PatroL (OWL) Network. During the test phase of this system, it is necessary to determine the range of brightness of the observable satellites. We have defined standard magnitude for Low Earth Orbit (LEO) satellites to calibrate their luminosity in terms of standard parameters such as distance, phase angle, and angular rate. In this work, we report the optical brightness range of five LEO Satellites using OWL-Net.

This study was conducted to evaluate effects of chopped and non-chopped rice straw on characteristics of silage-basedtotal mixed ration (TMR) according to the particle size, laceration, and in situ dry matter (DM) degradation. The threerice straw silages as low moisture unchopped (LMUC; 32.75% of moisture, unchopped), high moisture unchopped(HMUC; 42.05% of moisture, unchopped), and high moisture chopped (HMC; 44.71% of moisture, chopped to 30cmlengths) were tested. Samples were collected at every 5 minutes from 10 min of pre-mixing to 50 min. The percentageof >19mm in LMUC and HMC was decreased to 7.23% and 7.74% (p<0.05), respectively, and the percentage of 8mm>was increased to 5.81% and 5.24%, respectively. Furthermore, the laceration of forage by a TMR mixer showed that therewas little change in the reduction of 1.26% in HMC, but was reduced to 7.53% and 16.06% in LMUC and HMUC,respectively. The peNDF>8 was maintained 17~18.5% of the optimal requirement level for 15 to 45 min mixing in LMUCand for 30 to 50 min mixing in HMC, but it exceeded the level of peNDF>8 in the range of 21.49 to 22.53% for 50minmixing in HMUC. However, ruminal in situ DM degradation appeared as LMUC>HMUC>HMC. Therefore, theseresults suggest that the rice straw silage may be useful for high-yielding lactating cows, if it can be supplied with theadequate peNDF, and the limiting factor on DMI and DM degradation was reduced by crushing of the plant tissue, althoughthe rice straw silage was concerned to low quality forage.

A prototype of the GMT FSM has been developed to acquire and to enhance the key technology – mirror fabrication and tiptilt actuation. The ellipsoidal off-axis mirror has been designed, analyzed, and fabricated from light-weighting to grinding, polishing, and figuring of the mirror surface. The mirror was tested by using an interferometer together with CGHs, which revealed the surface error of 13.7 nm rms in the diameter of 1030 mm. The SCOTS test was employed to independently validate the test results. It measured the surface error to be 17.4 nm rms in the diameter of 1010 mm. Both tests show the optical surface of the FSMP mirror within the required value of 20 nm rms surface error.