• Korean Journal of Metals and Materials
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• v.48 no.3
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• pp.187-193
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• 2010

The solute carbon content in ferrite is one of the important factors to obtain good formability in low carbon steels. Although most of the carbons are consumed by the formation of grain boundary cementite during coiling after hot-rolling, the carbon content after coiling is normally observed much more than that of equilibrium. In this study, a classical nucleation and growth model is used to simulate the precipitation kinetics of the grain boundary cementite from coiling temperature (CT) to room temperature (RT). The predicted precipitation behaviors depending on the initial carbon content and the cooling rate are compared with the reported. As a result, the lateral growth of thickening of cementite is a major factor for the sluggish reaction of grain boundary cementite. The reduction of solute carbon content after coiling is divided into three regions: a) increase due to no cementite precipitation, b) decrease due to the fast length-wise growth of cementite, c) increase due to the slow thickness-wise growth of cementite.

• Korean Journal of Agricultural Science
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• v.48 no.2
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• pp.201-207
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• 2021

This study evaluated the influence of enzyme mixture supplementation on the growth performance, nutrient digestibility, and fecal score of growing pigs. A total of 72 pigs with an initial body weight of 20.23 ± 1.46 kg were randomly assigned to two treatments consisting of a basal diet and the basal diet supplemented with 0.5% enzyme mixture. During a 19-day trial, no significant difference was observed in the body weight (BW) and average daily feed intake (ADFI) of the pigs. However, a gradual increase in the average daily gain (ADG) was observed during the period from day 14 to day 19 and the overall period in pigs fed a diet supplemented with the 0.5% enzyme mixture (p < 0.10) as compared to the pigs that were fed the control diet. From days 4 to 14 and in the overall experiment, a gradual increase in the feed conversion ratio (FCR) (p < 0.10) was observed with the inclusion of 0.5% enzyme mixture supplementation. The nutrient digestibility of dry matter (DM), nitrogen (N), and energy were not affected by enzyme mixture supplementation. In addition, dietary supplementation with the enzyme mixture had no significant effects on the fecal score of growing pigs. In summary, supplementation with the enzyme mixture had beneficial effects on the ADG performance but failed to have a significant effect on growth performance (BW), nutrient digestibility, and fecal score.

• Korean Journal of Agricultural Science
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• v.49 no.2
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• pp.185-192
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• 2022

The purpose of this study was to investigate the effects of condensed molasses fermentation solubles (CMS) on the growth performance, nutrient digestibility, and backfat thickness of growing pigs. In an eight-week trial, a total of 120 cross-bred ([Landrace × Yorkshire]× Duroc) growing pigs with an average initial body weight (BW) of 25.84 ± 1.60 kg were used. The pigs were randomly assigned to one of two dietary treatments based on body weight and sex. The dietary treatments were as follows: CON - corn-soybean meal-based basal diet (CON) + 2% molasses; and TRT1 - CON + 2% CMS. Each treatment had 12 replicates with five pigs (three gilts and two castrated barrows) per pen. Though there were no significant differences observed in terms of the growth performance and nutrient digestibility (p < 0.05), the backfat thickness in pigs fed 2% CMS tended to increase in week 4 (p < 0.1). Thus, 2% CMS could be optimal to replace molasses given that it does not exert any adverse effects on the performance of growing pigs.

• Journal of Ocean Engineering and Technology
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• v.22 no.5
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• pp.94-99
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• 2008

Three types of salt resistant concrete beams reinforced with glass fiber reinforced polymer-ribbed bars (GFRP-ribbed bars) were selected, and their applicable properties were investigated with the goal of improving the problem of capacity deterioration in marine structures due to sea water corrosion. In this study, the structural behaviors were similar to RC beams in relation to the development of the strength and stiffness up to the generation of the initial crack. After the growth of this initial crack, the structural properties decreased owing to a sudden loss of bond strength. Also these beams showed the trends of brittle failure. As a result, it was confirmed that a GFS beam replaced with Fly Ash (20%) and Silica Fume (5%) has the best application as a marine structural element.

• Korean Journal of Child Studies
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• v.31 no.6
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• pp.1-13
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• 2010

This study examined the time-dependent effects of changes in private education on the trajectories of academic achievement among early adolescents. Five-wave data was employed from the KYPS; the participants being 2844 (1524 boys, 1320 girls). All were 4th graders in 2004 and became 8th graders in 2008. Latent growth curve model indicated that academic achievement significantly decreased over the five time points, but there were significant individual differences as well. Participants who reported higher initial levels of academic achievement tended to decrease in academic achievement more slowly over time compared to participants who reported lower levels of initial academic achievement. The effects of private education on academic achievement were at their most powerful when participants were in the 4th grade. Private educational experiences among 6th graders had relatively less influence upon the academic achievement of 7th graders.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.9
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• pp.1693-1699
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• 2011

In this paper, for magnetic silence technology of naval vessel, is to make lab deperm system and to evaluate the deperm capacity of naval vessel regarding deperm protocol. Initial permanent magnetic field of naval vessel is magnetized before deperm, having the magnetic field of the same size, to evaluate the deperm capacity regarding a variety of deperm protocol for experimental reliability growth. Current dead time effect of deperm protocol is measured at the different initial current, which are 8A, 6A and 4A respectively. Furthermore, the experiment under the same condition except changing duty cycle into 50% is carried out. As a result, it is possible to compare the six different experiment outcomes. The result shows that the experiment with dead time improve the deperm capacity more than 48.51 percent comparing to the case without dead time.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.723-729
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• 1995

A flocculating sugar tolerant yeast strain was isolated from fermenting Takju. This strain was identified as Saccharomyces cerevisiae CA-1 according to the Lodder's yeast taxonomic studies. The isolated yeast could grow in 50% glucose and in 7% ethanol in the YPD medium. It's optimal growth temperature, initial pH, shaking rate and initial glucose concentration for ethanol fermentation showed 35$\circ$C, 4.5, 150 rpm, 15%, respectively. Ethanol concentration was 63 g/l in 20% glucose after 24 hours, fermentation yield was 0.49 g-ethanol/g-glucose in 10% glucose after 24 hours and ethanol productivity was 3.09 g/l$\cdot $h in 10% glucose after 12 hours in batch fermentation. Repeated batch fermentation was possible for over 50 days and ethanol yield, ethanol productivity and substrate conversion rate were 0.39-0.50 g/g, 1.63-2.08 g/l$\cdot $h and more than 99%, respectively during these periods.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.225-228
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• 1997

YBa$_2$Cu$_3$O$_{x}$ samples with different amounts of $Y_2$BaCuO$_{5}$ were prepared by MPMG (Melt Powder Melt Growth) method. The effects on the size of initial particles and Ag addition for $Y_2$BaCuO$_{5}$ distribution in YBa$_2$Cu$_3$O$_{x}$ were invesgated. The samples prepared by the melting process usually have large grains up to several ㎣ and precipitates of $Y_2$BaCuO$_{5}$. The distribution of the $Y_2$BaCuO$_{5}$ particles in the samples depends on the size of initial particles and the amounts of Ag addition.Ag addition.

• Journal of Plant Biology
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• v.33 no.2
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• pp.105-110
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• 1990

Physiological gradient of IAA-oxidizing enzyme activities was investigated in order to elucidate the mechanism of shoot differentiation in Cymbidium sp. (‘Jungfrau’) protocorms by using phenolic compounds (2, 4-dichlorophenol, catechol), auxin-inhibitors (PCIB, TIBA), and hormones (GA3, ABA, BA). The activity of IAA oxidase was decreased in protocorms treated with catechol decreased the catalytic activity of IAA oxidase or TIBA but this enzyme activity was increased after a temporary decrease at initial stages in the presence of 2, 4-dichlorophenol or PCIB. The activity of IAA oxidase in BA-treated protocorms (white and crown gall-like) was the highest of all. However, the catalytic activity of peroxidase increased after a temporary decrease at initial period. These results suggest that shoot differentiation and growth may be influenced by effective IAA levels in the protocorms causing IAA-oxidizing enzyme and phenolic compounds.

• The korean journal of orthodontics
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• v.16 no.2
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• pp.31-41
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• 1986

The purpose of this study is to examine the initial reaction of craniofacial complex to the traction of headgears which are frequent used in dinical practice by using holographic interference method. Changes in the fringe pattern according to the traction conditions (outer bow length, load amount, direction) were compared. Human dry skull was used as experimental material, the results were as follows. 1. The density of fringes increased with an increase in load. 2. Maxillary headgear affected circummaxillary bones-temporal bone, zygomatic bone, nasal bone, frontal bone, sphenoid bone as well as maxilla. 3. The most upward-backward displacement was observed in a high pull head gear $(30^{\circ})$, this is though to be a optimal direction for supressing the growth of the maxilla.