• Applied Biological Chemistry
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• v.14 no.1
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• pp.99-102
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• 1971

These experiment were conducted to study the effects of various nitrogen sources and inorganic salts upon the growth of Saccharomyces rouxii T-9, and the results obtained were as follows: 1) The strain showed the most rapid growth in the case of 2.5 to 5.0% addition of peptone as an organic nitrogen source, and 1.0% addition of $(NH_4)_2HPO_4$ as an inorganic nitrogen source respectively to the media containing no NaCl. 2) Its growth was the most rapid in the case of 1.5% addition of yeast extracts as an organic nitrogen sources, and 5% addition of urea as an inorganic nitrogen source respectively to the media containing 20% of NaCl. 3) Its growth was the most rapid in the case of 1% addition of $NaNO_3$ as an inorganic salt to the media containing no NaCl, while to the media containing 20% or 26% of NaCl its growth was more rapid in the case of 5% addition of $NaNO_3$ than 1% addition. 4) Its growth was more rapid in the case of 0.5% addition of $MgSO_4\;and\;CaCl_2$ respectively to the media containing 20% of NaCl than to the media containing no NaCl, and was rapid in the case of 1% addition of $MgCl_2$ to the media containing 26% of NaCl.

• Journal of Korea Foundry Society
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• v.8 no.4
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• pp.453-458
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• 1988

Al-Si alloy powder produced by the gas atomizer showed fine eutectic structure between ${\alpha}-dendrites$, that was grown by coupled growth, and there remained small amount of ${\alpha}$ in Al - 20 wt% Si alloy. The morphology of Si in the eutectic structure was largely influenced by the recalescence caused by solidification latent heat, and that was thought to be due to decrement of the surface energy of Si. In modified eutectic Si by rapid solidification, fine twin about $0.01\;{\mu}m$ was observed and growth direction of eutectic Si was <112>. This fact implied that the growth mechanism of eutectic Si in rapid solidification was related to TPRE mechanism. Due to rapid solidification Si was soluble in ${\alpha}-phase$ in Al - 12.6wt%Si alloy up to about 3.4wt%, and the solubility of Si in ${\alpha}-phase$ reaches the equilibrium solubility stare after 60min, holding when it was held isothermally at $253-296^{\circ}C$.

• Analyses & Alternatives
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• v.4 no.2
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• pp.71-102
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• 2020

This study analyzes the effect of demographic changes on economic growth. We use the supply-side output identity to forecast the growth potential of the Korean economy. According to the results, even based on optimistic assumptions and prospects, the economic growth rate is likely to fall drastically starting in 2020. Of course, to maintain growth potential, efforts to increase productivity are necessary. However, given the historical experience of developed countries, it is not clear whether the huge trend of demographic change can be offset by efforts to increase productivity. In the so-called '30-50 club' countries, both labor productivity and growth rate tend to fall after reaching the per capita income of $30,000. The degree of decline in the growth rate is closely related to changes in the working age population and the prime-age workforce. The results are similar when tracking the path of changes in total factor productivities of the economy. When a certain level of income is reached, the increase in total factor productivity also tends to slow down. The ripple effects of rapid changes in demographics will indeed be extensive. The negative impact is likely to be concentrated at a time when the working age population, the prime-age workforce, and the total population shrink simultaneously. Above all, it is necessary to use the government's fiscal space to block the possibility of a rapid fall in the growth rate. In addition, it is important to continuously implement various reform tasks that should be promoted, such as improving the education system and strengthening the social safety net.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.6
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• pp.110-117
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• 2011

In order to study the growth models between the growth of Sedum takevimense and growth rate in soil with three types of mix ratios, this experiment was carried out on April 3rd, 2011. A nonlinearity regression analysis was performed using the Logistic and Gompertz models by SPSS. According to the study of growth models of Sedum takevimense, the process of growth and management methods after over-wintering were explicitly determined. According to the measured values, the growth in the soil of $P_1P_2V_1$ and $P_2P_1V_1$ was better than that of $P_1$. Particularly, the average length of Sedum takevimense in the soil of $P_1P_2V_1$ was about twice as great as that in the $P_1$. The fitness test of the two growth models was: The predicted value and measured value were separately compared and analysed, the average fitting precision $R^2$ of the Logistic models was 0.995, but the average $R^2$ of the Gompertz models was below 0.978, which showed that the Logistic models were better than the Gompertz models. The growth models also showed that the growth time of Sedum takevimense was divided into three: rapid, most rapid and slow. When managed in the rapid and the most rapid time, it will grow better.

• Journal of the Korean Ceramic Society
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• v.29 no.4
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• pp.305-311
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• 1992

As compared with conventional sintering, rapid heating in microwave system could enhance sinterability and final properties of alumina with a very short sintering time. In this study microwave sintering was performed using zirconia brick as a reaction chamber which was positioned in a 2.45 GHz(700 W) multimode microwave cavity. Microwave-sintered alumina showed high density and smaller grain size than conventionally sintered alumina because the ratio of densification rate/grain growth rate was increased by rapid heating.

• The Korean Journal of Ecology
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• v.1 no.2
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• pp.49-56
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• 1977

For the culture the population growth, shell length and spawning seasons of Gomphina veneriformis, and its environmental factors, were investigated at the Jeju coastal regions. from Feburuary, 1975 to March, 1976. The soil movements of the tidal flats where the clams inhabited were relatively rapid during the strong tidal actions. The rate of population growth were rapid from April to September, then became obsure. The relative growth equations of the shell height (SH) and the shell breadth (SB) against the shell length (SL) of the clams were as follows: Changhung : SH=0.751 SL + 0.685, SB=0.448 SL-0.630 Pyoson : SH-0.775 SL - 0.115, SB=0.464 SL-1.008 Hwhason : SH=0.794 SL - 0.923, SB=0.485 SL-1.155 Kwhagzee : SH=0.771 SL - 0.644, SB=0.455 SL-1.049 The meat weight increases of the clams were continued from March to late June, then it decreased sharply up to late August. The spawning of the clams seems to be late from June to Spetember in the regions studied.

• Proceedings of the Korea Database Society Conference
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• 2008.05a
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• pp.321-338
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• 2008

Information and communication industry, which shows rapid growth rate, is now leading the global economic growth, contributing a ripple effect on general business and economic structure. It is said that information and communication industry enables swift economic growth taking a role as a basic industry of information-oriented society. Especially, rapid technical innovation promotes mutual growth of other related industries and it is technology-intensive. The purpose of this research is to analyze the management efficiency of information and communication industry using DEA method, and finally suggest numerical value for inefficient organizations to improve their efficiency. CCR-I, BCC-I efficiency and RTS(Returns to scale) of 29 companies engaged in information and communication industry was evaluated. With the results, I suggested model companies for benchmarking in information and communication industry. To summarize, 7 companies were selected with CCR-I efficiency rate 1, and 12 companies with BCC-I efficiency rate 1. RTS was finalized with 8 IRS companies, 10 DRS companies, and 11 CRS companies.

• Korean Journal of Microbiology
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• v.22 no.3
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• pp.135-142
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• 1984

The effect of biotin on the growth and sporulation of Bacillus subtilis SNU816 was investigated. When B. subtilis SNU816 was cultured on glucose as a sole carbon source, the growth was retarded markedly and usually ceased at early log phawe. But by addition of biotin to this medium, normal, rapid growth was restored. The growth rate was increased proportionally according to the concentration of exogenous biotin until it reached to 0.05㎍/ml, at which about three fold rapid growth was achieved. Also biotin was required for optimum sporulation for it facilitated the complete utilization of both glucose(Glc) and glutamic acid(Glu). Without biotin in Glc+Glu medium, about 40% of glutamic acid was remained unutilized. The dipicolinic acid content of cells cultured in Glc+Glu medium without biotin was markedly small and sporulation was suppressed before free spore release. Since biotin could be partiallyreplaced by one of TCA cycle intermediates such as oxalacetic acid, citric acid, or glutamic acid in enhancing growth in Glc medium, it was postulated that this strain might have a defect in converting pyruvate to oxalacetate which process is known to be mediated by pyruvate carboxylase that requires biotin as a cofactor.

• Journal of Ocean Engineering and Technology
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• v.1 no.2
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• pp.93-100
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• 1987

Corrosion fatigue cracking of the austenitic stainless steel(bese metal & heat affected zone by TIG weld) was studied experimentally under the environments of various specific resistance and air. The characteristics of corrosion fatigue crack growth rate and the environmental constants of paris' rule were investigated for SUS 304 weldments in the various specific resistance. The influences of stress intensity factor range and corrosion on the crack growth rate were compared. The characteristics of corrosion fatigue cracking for the weldments were inspected from mechanical, electrochemical and microstructural point of view. Main results obtained are as follows: 1) As the specific resistance decreases, the environmental constant C of paris'rule increases(hence the corrosion fatigue crack growth rate is rapid), but the environmental constant m decreases, so the effect of corrosion to the crack growth rate is more susceptible than thet of stress intensity factor range. 2) As the stress intensity factor range decreases, the corrosion fatigue crack growth rate of heat affected zone is more susceptible than that of the base metal. 3) The corrosion fatigue crack growth rate of the heat affected zone is more rapid than that of the base metal, because of the phenomenon of softening and the less noble potential coused by wedlding heat cycle. 4) The corrosion fatigue cracking of SUS 304 weldment appears transgranular fracture.

• Journal of Preventive Medicine and Public Health
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• v.11 no.1
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• pp.31-40
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• 1978

For the purpose of estimating the status of physical growth of primary school students in Busan area, the author had performed an investigation and analysis on the physical integrated value for past 6 years of random sampled 656 students (male 374, female 282). The summarized results were as follows : 1. The most rapid growth age of body-height was 7-8 years old as 5.9 cm in male and 10-11 years old in female as 6.5 cm, and the growth curve of body-height was crossed at 10-11 years old. 2. The most rapid growth age of body-weight was 9-10 years old as 3.1 kg in male and 10-11 years old in female as 3.9 kg, and the growth curve of body-weight was crossed at 10-11 years old. 3. The most rapid growth age of chest-girth was 8-9 years old as 3.1 cm in male and 9-10 years old in female as 2.9 cm, and the growth curve of chest-girth was not corssed. 4. The most rapid growth age of sitting-height was 6-7 years old in both sex as 3.3 cm and 3.4 cm, and the growth curve of sitting-height was crossed at 8-9 years old. 5. Using the physical integrated value was much simple and desirable at comparing with the areas. And the physical integrated value of primary school students on Busan area compared to Korean standard physical status was relatively good as body-height +0.33, +0.30, body-weight +0.33,+0.35, chest-girth +0.65, +0.57 and sitting-height +0.10, +0.20 with each sex.