담배거세미나방핵다각체병바이러스대량생산연구에서, 5영충에 1.1×107다각체/ml로 접종 후 8일에 수확했을 때 한 마리당 6.7×109 다각체를생산할 수 있었으며, 이때 통과는 한 마리당 약 2g의 인공통과로 충분하였다. 합성유약 호르몬인 methoprene (Manta˚ledR)을 처리했을 때 종영유충기간이 1~2일 연장되었으며, 바이러스 생산에 있어서도 무처리에 비해 약 15% 증가되었다.

We have considered the mass loss effects on the analytical PMS stellar evolutionary model of Stein(1966). In this calculation, we have assumed the mass loss law, M˙=K(L/C)(R/GM)'-,which should be reasonable for PMS stellar wind mechanism. The numerically obtained evolutionary tracks in H-R diagram indicate that the higher mass losses PMS star have, the later they reach the radiative equilibrium. We have considered the composition effect on the evolution such as the composition difference between Pop. I and Pop. II PMS stars. We have also compared the tracks under the mass loss law, M˙=K'LR/GM.

Combining the luminosity functions of main sequence stars in 3 associations and 22 open clusters, the initial luminosity function and mass function for these clusters are derived. For stars of m > 0.6 m ⊙ , they are well consistent with those for the field stars.

We study the luminosity and mass functions of open clusters using the data published by the United States Navel Observatory to figure out the relationships between these functions and the cluster ages. Slope ranges of the luminosity (dlogN/dMv) and mass function (-dlogN/d(log m/m@)) are 0.09-0.52(avg.=0.26, var.=0.01), 0.43-5.49(avg.=1.7, var.=0.63) respectively. These large ranges do not support the mass function is universal, but the function is time dependent. Despite of the poor relationship between the luminosity function and the cluster age, we obtain a good relationship in the mass function. We can understand this good relationship with a viewpoint of stellar evolution. We do age analyses in terms of the metal abundance and the number density of the open clusters. We get the fact that the less metal abundances and the less number densities, the more steep in the slopes of the mass function.

The Wielen dip over the ragne of 6 < M υ < 9 in the luminosity function (LF) for the solar neighborhood stars could be explained by the combination of two different IMFs which yields the age of 13 billion years of the solar neighborhood. This smaller age than the Galactic age, 15 billion years indicates the slow collapse model of the Galaxy, solving the G-dwarf problem. Two different IMFs suggest two different mechanisms for star formation in the solar neighborhood.

Dynamical conditions for the fronts around the Yellow Sea Cold Water Mass, were investigated by means of the oceanographical data and simple numerical experiment. The coastal front developed along the coast inside the Yellow Sea and distinguished the Yellow Sea Cold Water Mass from the coastal water is attributed to the predominant tidal mixing near the coast. On the other hand the southern part of the front of the cold water mass would be explained a a part of the extention of a western boundary current which flows into the Cheju Channel.

From the kinematically unbiased sample of halo stars, the local mass density of halo dwarfs is estimated as 6.0 ∼ 6.3 × 10 − 4 m ⊙ / p c 3 by adopting a color-magnitude relation and a mass-luminosity relation. The derived halo mass density is not much different from the results of previous studies, which were derived from the kinematically biased sample of halo stars. Therefore it is confirmed that the local mass density of halo stars is far less than that required by Ostriker-Peebles to stabilize the galactic disk against barlike instabilities.

We derived initial mass functions (IMF) of massive stars in three different regions of spiral arms within 2.5kpc from the sun. The derived IMF slope β β of Local arm stars is found to be −2.09∼−2.06 −2.09∼−2.06 , very close to that of Bisiacchi et al. (1983). For Sagittarius-Carina arm stars β β ranges from -1.77 to - 1.72 which is close to that of overall stars given by Germany et al. (1982). Possible causes inducing the regional difference in IMFs are discussed.

Under the context of Stein's linear theory of stellar models, the luminosity-effective temperature relationship is derived for contracting pre-main sequence stars which are losing mass, according to the empirical formula, given by Reimers (1975). The effects of mass loss on their evolution are investigated by calculating evolutionary tracks of 1. 1.5M⊙ 1.5M⊙ , 5M⊙ 5M⊙ , and 10M⊙ 10M⊙ , stars. Our calculations reveal that the effects of mass loss show up in the radiative equilibrium stage of the evolution. It is found that an increase of mass loss rate leads to delay the onset of radiative equilibrium, thus resulting in under-luminous main sequence stars. It is also noted that the mass loss prolongs the pre-main sequence life time. Detailed results of the calculations are discussed.

N-logM diagrams of 29 open clusters are obtained by, using observational data and theoretical evolutionary track of stars on M_(bol)-T_(eff) diagram. A certain relation between the forms of N-logM diagrams and their ages are found. And a temporary interpretation is given for it.

The well observed 8 open clusters, NGC 6530, 2264, 654, 129, 2168, Pleiades, Praesepe and Hyades were selected on the basis of photometric observation and proper motion study. The luminosity functions (LF) and mass functions (MF) of these clusters are different with cluster age and they could be divided into three age groups (t< 10 7 yrs, 10 7 10 8 yrs, 10 8 10 9 yrs). From these LF's and MF's, the mean LF and MF of the open clusters are derived and these functions suggest the time-dependent initial mass function (IMF) and the variation of observed MF with cluster age.

The present day mass functions of main sequence stars in the well observed open clusters, Hyades, Praesepe, Pleiades, NGC 654 and NGC 6530 arc derived and compared with those computed from the model of time-dependent initial mass function and star formation rate. The agreements between the observed and computed present day mass functions suggest the importance of fragmentation process at the early phase and fragment interaction at the later phase of cluster evolution. This process of star formation is different from that related to the evolution of the solar neighborhood, and also could explain the lack of low mass stars observed in some open clusters.