• 한국세라믹학회지
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• 제22권5호
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• pp.43-46
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• 1985

Constitutional supercooling due to concentration gradient at solid-liquid interface in the melt can be avioded by increasing rotational speed for growing $LiNbO_3$ single crystals from the stoichiometric melt. Growth conditions for high quality crystals were determined by rotational speed by which other growth parameters were adjusted.

• 수산해양기술연구
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• 제53권4호
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• pp.471-475
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• 2017

This study aims to suggest the methodology to improve to estimate back-calculated fish growth parameters using weighted average. It is to contribute to correct errors in the calculation of back-calculated growth equation with unequal numbers of sample by age. If the numbers of sample were evenly collected by age, each back-calculated length at age was equal between arithmetic and weighted averages. However, most samples cannot be evenly collected by age in reality because of different catchability by fishing gear and limitation of environment condition. Therefore, the estimation of back-calculated length by weighted average method is essential to calculate growth parameters. There were some published growth equations from back-calculated length using a simple arithmetic average with different numbers of samples by age when searching for back-calculated growth equations from 91 relevant papers. In this study, the process of deriving growth equation was investigated and two different average calculations were applied to a fish growth equation, for example of Acheilognathus signifer. Growth parameters, such as $L_{\infty}$, k and $t_0$, were estimated from two different back-calculated averages and the growth equations were compared with growth performance index. Based on the correction of back-calculated length using weighted average by age, the changes by female and male were -14.19% and -5.23% for $L_{\infty}$, and 59.28% and 18.91% for k, respectively. The corrected growth performance index by weighted average improved at 7.05% and 2.46% by female and male, respectively, compared to the arithmetic averages.

• 한국재료학회지
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• 제2권1호
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• pp.52-57
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• 1992

용응인상법에 의해 융성시킨 $LiNbO_3$ 단결정의 거시적 결함은 단결정 육성인자인 성장속도, 온도구배 및 결정회전속도에 강하게 영향을 받았다. Cell 구조가 형성되지 않고 결정의 직경제어가 용이하며 결정성장 후 냉각시 에도 crack이 발생되지 않는 1" 직경의 $LiNbO_3$ 단결정의 성장조건은 온도기울기 $70~100^{circ}C/cm$, 성장속도 5~10 mm/hr, 결정회전속도 40 rpm 이었다. 이었다.

• 시스템엔지니어링학술지
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• 제16권1호
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• pp.1-8
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• 2020

In this paper we proposed to develop the reliability growth planning for the One-shot system using the PM2-Discrete model. The PM2-Discrete is the methodology specifically developed for discrete systems and is the first quantitative method available for formulating detailed plans in the discrete usage domain. First, the parameters RG, RI, T, MS and d of the PM2-Discrete model are set. Second, the case analysis was performed on One-shot system A. Third, the input parameter values were applied to drive the R(t) equation. Finally, using RGA 11 Software, the reliability Growth Planning Curve of One-shot system A was constructed. Also, the sensitivity analyses are performed for the changes of model parameters. The results of this study can be usefully used in establishing the reliability growth planning curve of the One-shot system.

• 한국토양비료학회지
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• 제50권5호
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• pp.409-421
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• 2017

Recently Unmanned Aerial Vehicle (UAV) technology offers new opportunities for assessing crop growth condition using UAV imagery. The objective of this study was to select optimal vegetation indices and regression model for estimating of rice growth using UAV images. This study was conducted using a fixed-wing UAV (Model : Ebee) with Cannon S110 and Cannon IXUS camera during farming season in 2016 on the experiment field of National Institute of Crop Science. Before heading stage of rice, there were strong relationships between rice growth parameters (plant height, dry weight and LAI (Leaf Area Index)) and NDVI (Normalized Difference Vegetation Index) using natural exponential function ($R{\geq}0.97$). After heading stage, there were strong relationships between rice dry weight and NDVI, gNDVI (green NDVI), RVI (Ratio Vegetation Index), CI-G (Chlorophyll Index-Green) using quadratic function ($R{\leq}-0.98$). There were no apparent relationships between rice growth parameters and vegetation indices using only Red-Green-Blue band images.

• 대한원격탐사학회지
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• 제16권2호
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• pp.109-116
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• 2000

This study was carried out to assess the use of RADARSAT data which is C-band with HH polarization for the rice growth monitoring in Korea. Nine time-series data were taken by shallow incidence angle (standard beam mode 5 or 6) during rice growing season. And then, backscattering coefficients ($\sigma$$^{\circ}$) were extracted by calibration process for comparing with rice growth parameters such as plant height, leaf area index(LAI), and fresh and dry biomass. Field experimental data concerned with rice growth were collected 8 times for the ground truth at the study area, Tangjin, Chungnam, Korea. At the beginning of rice growth, backscattering coefficients were ranged from -l6~-l3dB when rice fields were not covered with rice canopy and flooded. At the maximum vegetative stage of rice, backscattering coefficients of the rice field were the highest ranging from -4.4dB~-3.1dB. The temporal variation of backscattering coefficient($\sigma$$^{\circ}$) in rice field was significant in this study. Backscattering coefficient ($\sigma$$^{\circ}$) of rice field was a little bit lower again after heading stage than before. This results show RADARSAT data is promising for rice monitoring.

• Nuclear Engineering and Technology
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• 제53권1호
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• pp.304-313
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• 2021

Nickel base Alloy X-750, which is used as fastener parts in light-water reactor (LWR), has experienced many failures by environmentally assisted cracking (EAC). In order to improve the reliability of passive components for nuclear power plants (NPP's), it is necessary to study the failure mechanism and to predict crack growth behavior by developing a probabilistic failure model. In this study, The Bayesian inference was employed to reduce the uncertainties contained in EAC modeling parameters that have been established from experiments with Alloy X-750. Corrosion fatigue crack growth rate model (FCGR) was developed by fitting into Paris' Law of measured data from the several fatigue tests conducted either in constant load or constant ΔK mode. These parameters characterizing the corrosion fatigue crack growth behavior of X-750 were successfully updated to reduce the uncertainty in the model by using the Bayesian inference method. It is demonstrated that probabilistic failure models for passive components can be developed by updating a laboratory model with field-inspection data, when crack growth rates (CGRs) are low and multiple inspections can be made prior to the component failure.

• Journal of the Korean Wood Science and Technology
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• 제51권3호
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• pp.222-237
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• 2023

Eucalyptus pellita is one of the fast-growing tree species and has become predominant in Indonesian forest plantations. Meanwhile, tree breeding programs with clone development are the best way to provide greater genetic advantages. A better understanding of genetic control on growth and basic density in E. pellita is important for increasing wood productivity and quality. In this study, growth characteristics (tree height, diameter, and volume), basic density and its genetic parameters (heritability, genetic gain and genetic correlation) were determined. The number of clones tested in both trials was 50, divided into 5 blocks, and 5 trees/plot. The results showed that there were significant differences in growth and basic density among clones. There was an interaction between genetics and the environment further indicating the existence of unstable clones. The high heritability was found in tree height (0.82-0.86), diameter (0.82-0.90), and basic density (0.91-0.93). This implies that E. pellita has good opportunities for genetic improvement to increase wood productivity and quality. In addition, the results of genetic correlations among growth characteristics (height, diameter, and volume) and basic density showed positive moderate to highly significant value. It is suggested that these characters may be used to the advantage of the breeder for bringing improvement in these traits simultaneously. Therefore, this study provides important information of the genetic improvement of wood quality in E. pellita in Indonesia.

• 한국결정성장학회지
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• 제8권2호
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• pp.240-248
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• 1998

화학기상증착 방법에 의한 다결정 다이아몬드 박막성장을 위한 공정가운데 가장 많이 사용되는 기법중의 하나가 바로 플라즈마에 의한 방법이다. 특히 플라즈마 화학기상증착(Plasma-Enhanced CVD)기술에 의한 다이아몬드 박막응용은 그 공정에 대한 세부 조정을 통하여 더욱 향상시킬 수 있다. 다이아몬드 박막증착의 경우 중요 변수들은 다이아몬드 필름이 증착되는 기판(substrate)의 온도, $CH_4/H_2$가스비율, 전체가스 압력 및 가스 excitation에너지 등이다. 분광 ellipsometry는 다이아몬드 필름 증착과 관련된 극단적인 환경에서도 물리적인 접촉이나 만들어지는 샘플의 손상없이도 필름자체의 여러 성질뿐만 아니라 기초 샘플의 온도까지도 결정할 수 있는 좋은 방법이다. 이러한 장점들을 이용하여 양질의 다이아몬드 박막을 성장시키기 위한 조건과 그에 따른 박막 특성을 얻기 위하여 분광 ellipsomerry의 사용과 해석이 소개된다. 그리고, 분광 ellipsometry를 이용, 플라즈마 화학기상증착 기술에 의하여 성장되는 다이아몬드 박막으로부터 나타나는 중요 변수들이 결정될 것이며 이러한 변수들은 필름의 두께, 필름에 포함되는 void 및 비다이아몬드의 체적비와, 그들의 시간에 따른 변화등을 포함한다. 그리고 샘플이 원하는 두께까지 성장된 후에 라만 분광기로 측정되어 다이아몬드 성분을 확인한다.

• Fisheries and Aquatic Sciences
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• 제18권4호
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• pp.379-385
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• 2015

We studied the effects of the proprietary prebiotic Immunogen$^{(R)}$ on the growth, hematology and gut microbiota of common carp fingerlings. A basal diet was formulated using common feed ingredients and supplemented with Immunogen$^{(R)}$ at concentrations of 0, 5, 10, 20 and $40g\;kg^{-1}$, each of which was tested experimentally on replicated groups of fish. The trials ran for 8 weeks. Common carp fingerlings with an initial weight of $4.82{\pm}0.05g$ were randomly distributed among the experimental tanks at a stocking density of 25 fish per tank. The experimental diets were provided thrice per day; on each occasion the fingerlings were given a weight of feed that amounted to 4% of fish biomass. At the end of the experimental period, we determined the growth performance, feed conversion ratio, hematological parameters, body composition and gut micro-flora parameters of the test fish. Inclusion of $5g\;kg^{-1}$Immunogen$^{(R)}$ in the diet significantly improved growth performance and feed utilization in comparison with controls. However, the whole-body composition of the fish was not significantly influenced by prebiotic inclusion. Inclusion of $5g\;kg^{-1}$ Immunogen$^{(R)}$ significantly increased the total bacterial and Lactobacillus counts in fish intestines, but these bacterial parameters were significantly negatively impacted by higher concentrations of the prebiotic. Red blood cells counts were increased by prebiotic dietary supplementation at concentrations of 5 and $10g\;kg^{-1}$ prebiotic. Glucose and cholesterol levels were elevated by administration of Immunogen$^{(R)}$. Thus, dietary supplementation with $5g\;kg^{-1}$ Immunogen$^{(R)}$ improved fingerling common carp growth performance and feed utilization, and beneficially influenced the gut microflora