• Journal of the Korea Society of Computer and Information
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• v.21 no.10
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• pp.125-133
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• 2016

In this paper, we propose a real-time fault monitoring and dual system design of the countdown time-generating system, which is the main component of the mission control system. The countdown time-generating system produces a countdown signal that is distributed to mission control system devices. The stability of the countdown signal is essential for the main launch-related devices because they perform reserved functions based on the countdown time information received from the countdown time-generating system. Therefore, a reliable and fault-tolerant design is required for the countdown time-generating system. To ensure system reliability, component devices should be redundant and faults should be monitored in real time to manage the device changeover from Active mode to Standby mode upon fault detection. In addition, designing different methods for mode changeover based on fault classification is necessary for appropriate changeover. This study presents a real-time fault monitoring and changeover system, which is based on the dual system design of countdown time-generating devices, as well as experiment on real-time fault monitoring and changeover based on fault inputs.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.3
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• pp.303-307
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• 1990

In this paper, the factors of 1680 marine casualties occurred during 1986-1988 are analysed by the Principal Component Analysis. The main results are as follows: 1. Most of marine casualties result from the human factors such as careless operation and insufficient engine maintenance. Engine trouble is main part of accidents and great number of accidents is rated for fishing vessels. 2. Accidents are serious in case of cargo ships, passenger ships and tankers from the point of view of the damage of human life and properties. On the other hand, those are not so serious matter in case of fissing vessels and governmental vessels. 3. Grounding, collision and capsizal mainly result from careless operation, however material defect result in flooding

• Journal of Forest and Environmental Science
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• v.6 no.1
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• pp.18-28
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• 1989

The purpose of this study is to emphasize the indispensability and generalization of ecological approach in landscape planning and design, by describing the main ecological principles and the process and method applying them to landscape planning and presenting the case study of ecological planning. Landscape architecture is the science dealing with nature and therefore ecological approach in it cannot be emphasized too much. The main ecological principles that must be considered in landscape planning and design are energy flow, food chains, biogeochemical cycles, limiting factors, carrying capacity and homeostasis, vegetational succession, ecotone and edge effect, ecological niche, etc.. The seven component factors of natural ecosystem are climate, geology, physiography, hydrology, soil, vegetation, wildlife. These seven factors are interrelated by the above mentioned ecological principles. In landscape planning and design process, it is necessary that landscape architect should interpret and assess not only the component factors of natural ecosystem but also the interrelationships and ecological principles immanent in them and apply the data to final plan.

• Journal of Astronomy and Space Sciences
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• v.3 no.1
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• pp.41-51
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• 1986

Two-photometric light curves(Oh and Chen 1984) of the eclipsing binary TX UMa have been analyzed by the method of differential corrections of the model of Wilson and Devinney (1971). The system found to be simi-detached with the cooler and less massive component filling its Roche lobe. The absolute dimensions have been derived from the results of the photometric solutions with the spectroscopic elements of Hiltner(1945). It is assumed that the B8V primary component is on the zero main sequence stage of the core hydrogen burning and the secondary is at the core contraction stage after the shell hydrogen burning stage according to the Iben's (1967) evolutional tracks for $3.0m_\odot$ and $1.0m_\odot$ .

• Journal of Environmental Impact Assessment
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• v.18 no.6
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• pp.401-409
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• 2009

Multivariate statistical approaches to classify sampling sites with measuring their similarity by water quality data and understand the characteristics of classified clusters have been discussed for the optimal water quality monitering network. For empirical study, data of two years (2005, 2006) at the 9 sampling sites with the combination of 2 depth levels and 7 important variables related to water quality is collected in Yongdam reservoir. The similarity among sampling sites is measured with Euclidean distances of water quality related variables and they are classified by hierarchical clustering method. The clustered sites are discussed with principal component variables in the view of the geographical characteristics of them and reducing the number of measuring sites. Nine sampling sites are clustered as follows; One cluster of 5, 6, and 7 sampling sites shows the characteristic of low water depth and main stream of water. The sites of 2 and 4 are clustered into the same group by characteristics of hydraulics which come from that of main stream. But their changing pattern of water quality looks like different since the site of 2 is near to dam. The sampling sites of 3, 8, and 9 are individually positioned due to the different tributary.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.125-125
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• 1998

Glycyrrhizin (18$\beta$-glycyrrhetic acid $\beta$-D-glucuronyl a-D-glucuronic acid, GL), a main component of liquore extract (Glycyrrhiza glabra), is ingested orally as a component in the oriental medicine. By human intestinal bacteria, glycyrrhizin (18$\beta$-glycyrrhetinic acid $\beta$-D-glucuronyl a-D-glucuronic acid, GL) was metabolized to glycyrrhetinic acid (GA): main pathway metabolizing GL to GA by glucuronidases of Bacteroides J-37 (Kim et al., 1997) and Eubacterium sp strain GLH (Akao et al., 1987) and minor pathway metabolizing GL to GA via 18$\beta$-glycyrrhetic acid D-glucuronic acid (GAMG) by $\beta$-glucuronidase of Streptococcus LJ-22 and glucuronidases of Bacteroides J-37 / E. coli. $\beta$-Glucuronidase from Streptococcus LJ-22 hydrolyzed GL to GAMG, not GA. $\beta$-Glucuronidase of Streptococcus LJ-22 hydrolyzed $\beta$-glucuronic acid conjugates of polysaccharides rather than aglycone-$\beta$-glucuronides Optimal pH of Streptococcus LJ-22 $\beta$-glucuronidase was 5-6 and its molecular weight was 250 kDaltons. Km for GL was 0.37mM.

• Herbal Formula Science
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• v.28 no.2
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• pp.211-242
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• 2020

Objectives : This report describes 142 prescriptions related to the use of Astragalus mainly blended from Dongeuibogam. Methods : The following conclusions were drawn through investigations on the pre-scriptions that use Astragalus as a key component. Results : Prescriptions that Radix Aconiti Lateralis Preparata was taken as a monarch drug are utilized for 31 therapeutic purposes, for example, cold disease, stool disease, child disease. In particular, 17.3% of prescriptions appear in the chapter of cold. Prescriptions that utilize Radix Aconiti Lateralis Preparata as the main component are used in the treatment of cold, diarrhea and child disease, Bi syndrome due to pathogenic wind, cold and damp and they are also used for treating 55 different types of disease. Radix Aconiti Lateralis Preparata is used in pathogenic factors such as wind, cold and dampness and used in pathology related to the kidney and spleen and stomach system. The dosage of Radix Aconiti Lateralis Preparata is 2pun(about 0.75g) to 5don(about 18.8g), however 1don(about 3.75g)~1don 5pun(about 5.63g) has been taken the most for clinical application. Conclusions : Gangbutang and Ijungtang are the most useful base prescriptions which use the Radix Aconiti Lateralis Preparata as the main ingredient.

• Journal of The Korean Astronomical Society
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• v.48 no.6
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• pp.325-331
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• 2015

We study an association between the duration of solar activity and characteristics of the latitude distribution of sunspots by means of center-of-latitude (COL) of sunspots observed during the period from 1878 to 2008 spanning solar cycles 12 to 23. We first calculate COL by taking the area-weighted mean latitude of sunspots for each calendar month to determine the latitudinal distribution of COL of sunspots appearing in the long and short cycles separately. The data set for the long solar cycles consists of the solar cycles 12, 13, 14, 20, and 23. The short solar cycles include the solar cycles 15, 16, 17, 18, 19, 21, and 22. We then fit a double Gaussian function to compare properties of the latitudinal distribution resulting from the two data sets. Our main findings are as follows: (1) The main component of the double Gaussian function does not show any significant change in the central position and in the full-width-at-half-maximum (FWHM), except in the amplitude. They are all centered at ~ 11° with FWHM of ~ 5°. (2) The secondary component of the double Gaussian function at higher latitudes seems to differ in that even though their width remains fixed at ~ 4°, their central position peaks at ~ 22.1° for the short cycles and at ~ 20.7° for the long cycles with quite small errors. (3) No significant correlation could be established between the duration of an individual cycle and the parameters of the double Gaussian. Finally, we conclude by briefly discussing the implications of these findings on the issue of the cycle 4 concerning a lost cycle.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.957-961
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• 2010

Multivariate statistical approaches to classify sampling sites with measuring their similarity by water quality data. For empirical study, data of two years at the 9 sampling sites with the combination of 2 depth levels and 7 important variables related to water quality is collected in reservoir. The similarity among sampling sites is measured with Euclidean distances of water quality related variables and they are classified by hierarchical clustering method. The clustered sites are discussed with principal component variables in the view of the geographical characteristics of them and reducing the number of measuring sites. Nine sampling sites are clustered as follows; One cluster of 5, 6, and 7 sampling sites shows the characteristic of low water depth and main stream of water. The sites of 2 and 4 are clustered into the same group by characteristics of hydraulics which come from that of main stream. But their changing pattern of water quality looks like different since the site of 2 is near to dam. The sampling sites of 3, 8, and 9 are individually positioned due to the different tributary.

• Journal of Powder Materials
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• v.10 no.4
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• pp.235-240
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• 2003

The $Al/Al_2O_3$ composites fabricated by powder in sheath rolling method were cold-rolled by 50% reduction and annealed for 1.8 ks at various temperatures ranging from 200 to 50$0^{\circ}C$, for improvement of the mechanical properties. The mechanical properties and texture of the composites after rolling and annealing were investigated. The tensile strength of the composites increased significantly due to work hardening after cold rolling, however it decreased due to restoration after annealing. The strength of the composites was improved by thermo mechanical treatment. On the other hand, the texture evolution with annealing temperatures wa,i different between the unreinforced material and the composites. The unreinforced material showed a deformation (rolling) texture of which main component is ｛112｝<111> at annealing temperatures up to 30$0^{\circ}C$. However, the composites have already exhibited a recrystallization texture of which main component is ｛001｝<100> after annealing at 20$0^{\circ}C$. This proves that the critical temperature for recrystailization is lower in the composites than in the unreinforced ones.