• 한국결정성장학회지
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• 제3권2호
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• pp.117-124
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• 1993

연속성장법은 crystal growth chamber의 상부에 있는 reservoir에서 원료 분말을 연속적으로 공급하면서 도가니 하부에 용융대를 형성시킨 후, 종자결정을 용융대에 dipping하여 회전시키면서 아래로 끌어내려 단결정을 성장시키는 방법이다. 본 연구에서는 연속 성장법을 이용하여 silicon 단결정을 육성시켰으며 연속성장에 영향을 미치는 인자는 critical melt level, 원료공급속도, 성장속도, graphite crucible과 gruphite susceptor의 형태, work coil의 위치에 따른 graphite susceptor의 수직온도구배, 중력과 종자결정의 회전에 의한 원심력이 용융대의 안정화에 미치는 영향과 용융액 표면에서 일어나는 소결현상에 관해 고찰하였다.

• 한국해양공학회지
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• 제11권3호
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• pp.76-88
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• 1997

Constant .DELTA.K fatigue crack growth rate experiments were performed by applying an intermediate single and multiple overload for structural steel, SM45C. The purpose of the present study is to investigate the influence of multiple overloads at various stress intensity factor ranges and the effect of statistical variability of crack retardation behavior. The normalized delayed load cycle, delayed crack length and the minimum crack growth rate are increased with increasing baseline stress intensity factor range when the overload ratio and the number of overload application were constant. The crack retardation under low baseline stress intensity factor range increases by increasing the number of overload application, but the minimum crack growth rate decreases by increasing the number of overload application. A strong linear correlation exists between the minimum crack growth rate and the number of overload applications. And, it was observed that the variability in the crack growth retardation behavior are presented, the probability distribution functions of delayed load cycle, delayed crack length and crack growth life are 2-parameter Weibull. The coefficient of variation of delayed load cycle and delayed crack length for the number of 10 overload applications data are 14.8 and 9.2%, respectively.

• 대한기계학회논문집B
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• 제29권5호
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• pp.633-642
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• 2005

Nucleate pool boiling experiments for R11 under a constant wall temperature condition were carried out. A microscale heater array was used for the heating and the measurement of high temporal and spatial resolution by the Wheatstone bridge circuit. Very sensitive heat flow rate data were obtained by the control for the surface condition with high time resolution. The measured heat flow rate shows a discernable peak at the initial growth stage and reaches an almost constant value. In the thermal growth region, bubble shows a growth proportional to $t^{\frac{1}{5}}$. The bubble growth behavior is analyzed with a dimensionless parameter to compare with the previous results in the same scale. As the wall superheat increases, the departure diameter and the departure time increase, and the waiting time decreases. But the asymptotic growth rate is not affected by the wall superheat change. The effect of the wall superheat is resolved into the suggested growth equation. Dimensionless parameters of time and bubble radius characterize the thermal growth behavior well, irrespective of wall condition. The comparison between the result of this study and the previous results shows a good agreement at the thermal growth region. The quantitative analysis for the heat transfer mechanism is conducted with the measured heat flow rate behavior and the bubble growth behavior. The required heat flow rate for the volume change of the observed bubble is about twice as much as the instantaneous heat flow rate supplied from the wall.

• KSBB Journal
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• 제13권6호
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• pp.730-734
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• 1998

An이ew식과 Aiba삭을 조합하여 에탄올 생산단주인 Saccharomyces cerevisiae ATCC 24858의 비성장속도를 당농도와 에탄올 농도의 함수로 표현하였다. 기침의 저해영향을 받지 않는 최대 당농도 $S_m$은 150 g/L이며 기질의 저해영향은 기질농도 S와 $S-S_{max}$항의 함수로 표현되었다. 최대 비성장 속도 ${\mu}max 는 0.49 hr^{-1}, Monod상수 K_s$는 19 g/L, Andrew식의 기질저해상수 $K_1$는 139 g/L이였다. 또한 비성장속도에 영향을 마치지 앓는 최대알콜농도 Pm이 존재하였으며 그 값은 2 g/L 이였다. 따라서 Aiba식에서 비성장속도에 영향을 미치는 에탄올 농도항은 P-Pm으보 표현되었다. 본 연구의 알코올생산균주에 대한 비성장속도의 완성된 수식은 디음과 같으며 이 수식에 위한 계산값은 평균오차 6% 내외의 범위에서 실험값과 일치하였다.

• 한국인구학
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• 제31권1호
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• pp.27-54
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• 2008

본 논문은 최근 출산율 저하와 인구고령화로 인한 성장잠재력의 저하에 대한 우려가 높아지고 있는 상황에서 성장잠재력을 제고하는 정책의 성공 여부는 인적자본의 양적.질적 제고를 통한 생산성 향상에 달려 있음으로 파악하고, 인구구조의 변화, 노동시장 조건의 변화 및 노동생산성의 변화 등이 잠재성장률에 미치는 영향을 분석하는 것을 목적으로 하고 있다. 이를 위해 성장회계 접근방식을 이용하여 1인당 GDP 증가율을 인구구조의 변화에 따른 부양비의 변화와 노동투입 요소의 양적.질적 부분의 변화로 분해하였다. 우선, 노동투입의 양적인 변화는 고용률과 근로시간의 변화에 기초하여 시산하였으며, 노동투입의 질적인 변화는 인적자본에 대한 투자가 노동생산성에 미치는 영향을 감안하였다. 또한 출산율과 여성고용을 제고하는 정책효과를 분석하기 위해 출산율과 여성의 고용률을 주요 정책변수로 한 정책시뮬레이션을 하였다. 1인당 GDP 증가율의 베이스라인 전망결과는 2010년까지 연평균 4%대 중반의 성장률을 보이다가, 2020년대에는 3.94%, 2030년대에는 3.03%, 2040년대에는 2.41%로 서서히 감소할 것으로 나타났다. 또한 출산율 제고에 따른 성장률 효과는 2030년을 지나서 반영이 되며, 고출산율 시나리오 (2030년 이후 합계출산율이 1.57명으로 유지)의 경우 베이스라인보다 2030년대 이후 연평균 약 0.10%p 높은 1인당 GDP 성장률을 보일 것으로 전망되었다. 한편, 여성고용률이 제고되는 시나리오(2025년 이후 $25{\sim}54$세 여성의 고용률이 74.5%로 상승)의 경우 베이스라인보다 2050년까지 연평균 0.04%p 높은 1인당 GDP 성장률을 보일 것으로 전망되었다. 본 연구는 양적인 노동투입의 효과만으로는 성장잠재력에 미치는 영향이 그다지 크지 않으며, 궁극적으로 노동생산성의 향상과 같은 질적인 요소의 증대가 성장잠재력 확충에 중요한 대안이 됨을 알려 주고 있다.

• 유기물자원화
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• 제18권4호
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• pp.45-53
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• 2010

여러 가지 방법으로 전처리된 느타리 버섯 폐배지에 대한 줄지렁이 개체군의 섭식률 및 생장률을 조사하였다. 갓 발생한 버섯폐배지의 부숙기간을 달리하여 지렁이에게 급이하였을 경우, 20일 이상 부숙된 버섯 폐배지보다 10일 이하로 부숙된 버섯 폐배지에 대한 지렁이 개체군의 섭식량 및 생장률이 높았다. 분변토를 첨가한 버섯폐배지나 질소영양원으로서 요소비료를 첨가하여 부숙한 버섯폐배지는 지렁이 개체군의 섭식률과 생장률을 증대시키지 못하는 것으로 나타났다. 그러나 버섯폐배지를 분쇄하여 공급하였을 경우에는 섭식량 및 생장률이 증가하였다. 특히 분쇄된 버섯폐배지에 미강을 첨가하였을 경우에는 분쇄하지 않은 단순 버섯폐배지보다 생장률이 1.85배 증가하였다.

• 한국패류학회지
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• 제21권1호
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• pp.65-70
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• 2005

The purpose of this study is to determine the appropriate substrate for larval settlement and spat growth in the purple clam, Saxidomus purpuratus in laboratory culture. Larvae were reared with 3 different types of sediments (mud, sand, and mixed) for 46 days in settlement experiment, and settled spats were further grown in 3 types of sediments for 36 weeks in growth experiment. The density of settled spats in muddy sediments was more than 2 times higher than those in mixed or sandy sediments. But, the average size of settled spats in muddy sediments was smaller than those in mixed or sandy sediments. After 36 weeks of growth period, growth rate decreased as shell length increased. When shell length was less than 2 mm, growth rate in mixed sediments was significantly higher than that in sandy sediments. When shell length was more than 2 mm, there was no significant difference in growth rate among different substrates. Sediment type affected growth rate only when the spats were relatively small (less than 2 mm). Muddy sediments seems better for larval settlement, while mixed sediments is best for spat growth. We suggest the laboratory procedure for enhancing seedling production of S. purpuratus.

• 한국작물학회지
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• 제45권1호
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• pp.1-5
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• 2000

Leaf area is critical for crop light interception, and thereby has a substantial influence on crop yield. This experiment was conducted to characterize the development of soybean [Glycine max (L.) Merr.] leaf area. Plastochron index and leaf relative growth rate of Jackson was contrasted with the PI416937, which also has demonstrated tolerance to drought. First, plastochron ratio (PR) and plastochron index (PI) were evaluated in greenhouse to compare the leaf growth rate between two genotypes under well-watered condition. There was reasonable constancy of PR between two genotypes. The PR means of Jackson and PI416937 were 0.41 and 0.44, respectively. A fairly smooth increase of PI during vegetative stage was observed. Second, the relative growth rates were graphed against leaf area, normalized with respect to final leaf area, under well-watered and water-deficit conditions. Leaf growth was sustained longer in well-watered condition than water-deficit condition and there was a sizable proportion of leaves which was ceased earlier their growth in water-deficit condition compared to well-watered condition. The leaf relative growth rate of Jackson until leaves had completed at 45% of their growth during water deficit period was higher than that of PI416937.

• Mycobiology
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• 제38권3호
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• pp.210-214
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• 2010

Selection of fungal strains with high virulence against the developmental stages of Bemisia tabaci was performed using internal transcribed spacer regions. The growth rate of hyphae was measured and bioassay of each developmental stage of B. tabaci was conducted for seven days. All of the fungal strains tested were identified as Lecanicillium spp., with strain 4078 showing the fastest mycelium growth rate (colony diameter, 16.3 $\pm$ 0.9 mm) among the strains. Compared to strain 4075, which showed the slowest growth rate, the growth rate of strain 4078 was increased almost 2-fold after seven days. Strains 4078 and Btab01 were most virulent against the egg and larva stages, respectively. The virulence of fungal strains against the adult stage was high, except for strains 41185 and 3387. Based on the growth rate of mycelium and level of virulence, strains 4078 and Btab01 were selected as the best fungal strains for application to B. tabaci, regardless of developmental stage.

• Asian Pacific Journal of Cancer Prevention
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• 제13권7호
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• pp.3229-3232
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• 2012

In this study, cancer incidence data were assessed to provide various rates of five year age groups for a given year, lying between two census years. The individual exponential growth rate method is most useful in both population-based and non-population cased cancer registries in India to estimate the population by five yearly age groups and also find the rates of crude rates, age standard rates and cumulative rates. This method has been shown to endure from bias and often results sacrificing the overall growth rate and correction factor must be needful in five year age group population to maintain it. A second method, the difference distribution method is also able to maintain the overall growth rate and overcome the bias in estimation of five yearly age group populations. From this point of view these methods serving a new technique for population estimation by five yearly age groups for inter census years.