Densification behavior and grain growth of tool steel powder compacts during pressureless sintering, sinter forging, and hot isostatic pressing were investigated. Experimental data were compared with results of finite element calculations by using the constitutive model of Abouaf and co-workers and that of McMeeking and co-workers. Densification and deformation of tool steel powder compacts were studied by implementing power-law creep, diffusional creep, and grain growth into the finite element analysis. The shape change of a powder compact in the container during hot isostatic pressing was also studied. The theoretical models did not agree well with experimental data in sinter forging, however, agreed well with experimental data in hot isostatic pressing.

The Nara Dynasty of Japan lasted from 710 to 784 A.D, which corresponds to the period of the Unified Shilla Kingdom of Korea. The Nara Dynasty enacted the 'Daiho Law and Ordinance' by referring to those of Tang Dynasty of China. Under these legal systems, the Ministries were defined, and foods were used for paying taxes or as currency. The characteristics of the dietary culture in Nara Dynasty were as follows. 1) They obtained food from rice and other grain farming, hunting and fishery. Rice was their main staple and was also used for preparing porridge and brewing wine. 2) Under the influence of Buddhism, meat was prohibited, and milks or dairy products were supplemented for improving malnutritional status. 3) They also used seasonings, spices and sweeteners to enhance the taste and produced medicines by extracting plants, animals and minerals. 4) While chopsticks were made of bamboo, willow, silver, shell, tree or bronze, such utensils as pan earthenware steamer, or charcoal pots were used for preparing meals. 5) Highly qualified utensils, made of porcelains painted with lacguetr, metal, glass, horn and stone, were produced as handcraft art wad developed. 6) Chinese style cousines and cooking methods were popular and various types of preserving techniques like drying or salting were used. Processed cookies were also developed. 7) Although flour was used mainly among noble class people, ordinary people also used it. The royal families ate milk products a lot and even fried foods. 8) One can say that Buddism exerted an influence on Vegetarianism from this era.

Flow and heat transfer characteristics of gas, and trajectories and cooling characteristics of droplets/particles in a gas atomizer were investigated by a numerical simulation using FLUENT code. Among several kinds of solution method, the k- turbulent model, power-law scheme, SIMPLE algorithm is adopted in this study. Momentum and heat exchange between a continuous phase(gas) and a dispersed phase(particle) were taken into account. Particle trajectories are simulated using the Lagrangian method, and Rosin-Rammler formula is used for the particle size distribution. Streamlines, velocities and pressures of gas, and trajectories, velocities and cooling rates of particles have been investigated for the various gas inlet conditions. Small but very intensive recirculation is found just below the melt orifice, and this recirculation seems to cause the liquid metal to spread radially. Particle trajectory depends on the particle size, the location of particle formation and the turbulent motion of gas. Small particle cools down rapidly, while large diameter particles solidify slowly, and this is mainly due to the differences in thermal inertia.

The aim of the paper is to analyse the extinction law in the giant H II region NGC 3603. The ratio R is found to be greater than 5.0. In front of the cluster the reddening law is found to be normal. We have obtained a distance of ~5.3 Kpc which is significantly smaller than those adopted so far.

We have analyzed the content of the Korean stone star chart. Ch'on-Sang-Yul-Cha-Bun-Ya-Ji-Do(here-after Ch'on-Sang-Do). In the star map we have found 1468 stars, 4 more than the Chinese star catalog Bo-Chun-Ga. The four extra stars form a constellation, Jong Dae Boo. The map projection law used in the star chart is found to be the polar equtorial and equidistance projection. The linear distance of an object on Ch'on-Sang-Do from the center is linearly proportional to the north polar angular distance. We have found from a statistical analysis that most stars with declination lower than 50 are at positions representing the epoch of around the first century. On the other hand, stars near the north pole with declination higher than 50 are at the epoch of about 1300, which is close to the time the chart was engraved. This implies that the original Ko-Gu-Rye Dynasty's star chart has been revised by astronomers of Cho-Sun Dynasty. We have also shown that stars on Ch'on-Sang-Do are engraved in such a way that their area is linearly proportional to the visual magnitude.

To understand the dynamical structures of stellar wind bubble, one and two-dimensional calculations has been performed. Using FCT Code with cooling effects and assuming constant mass loss rate and ambient medium density, we could divide stellar winds into the regime of slow and fast winds. The slow wind driven bubble shows initially radiative and becomes partially radiative bubble in which shocked stellar wind zone is still adiabatic. In contrast., the fast wind driven bubble shows initially fully adiabatic and becomes adiabatic bubbles with radiative outer shell. We also determine analytically the onset of thin-shell formation time in case of fast wind driven bubble with power-law energy injection and ambient density structure. We solve the line transfer problem with numerical results in order to calculate line profile of [OIII] forbidden line.

A large scale 13CO(J=1-0) survey was made for CMa OB1/R1 region in 220° ≤ l 230° and -10° ≤ b ≤ 10° with a 8' spacing by using the 4 m radio telescope of Nagoya University. 34 isolated clouds were identified in this survey. Among them, two clouds were firstly identified by us. The observed LSR velocity indicate that almost of the all clouds are located in the Local arm, except two extreme velocity. The mass spectrum of the clouds in the Local arm is best fitted by a power-law index of 1.6.

I discuss implications of gamma-ray emission from blazars based on electron acceleration by shock waves in a relativistic jet. The number spectrum of electrons turns out to be a broken power law; while at low energies the power law index has a universal value of 2, at high energies it steepens to an index of 3 because of strong radiative cooling. This spectrum can basically reproduce the observed spectral break between X-rays and gamma-rays. I show that energetics of relativistic jets can be well explained by this model. I estimate physical quantities of the relativistic jets by comparing the prediction with observations. The results show that the jets are particle dominated and are comprised of electron-positron pairs. A connection between gamma-ray emission and radiation drag is also discussed.

We determine analytically the onset of thin-shell formation time of fast wind bubble with power-law energy injection Ein=E0ts Ein=E0ts , and power-law ambient density structure, ρ0(r)= ¯ ρ(r/ ¯ r)−ω ρ0(r)=ρ¯(r/r¯)−ω . Thin-shell formation time, tsf tsf can be estimated by minimizing the total time elapsed before the complete cooling of shocked gas. For uniform medium (ω=0 ω=0 ) and constant energy injection (s = 1), the onset of shell formation is found to be at tsf=5.2×103yr tsf=5.2×103yr , which agrees Quite well with the results of FCT 1D numerical calculation. We solve the line transfer problem with previous result derived by numerical calculation in order to calculate line profile of [OIII] (λ=5007\AA) forbidden line. In general, radiative outer shell causes the formation of double peaked line profile. Each peak corresponds to approaching and receeding shells with large velocities. Our line profiles show good agreements with observation of expanding shell structure.