• 한국컴퓨터정보학회논문지
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• 제21권10호
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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.

• 수산해양기술연구
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• 제26권3호
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• pp.303-307
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• 1990

1986년부터 1988년까지 3년 동안 우리나라 주변 해역에서 발생한 1680건의 해난사고를 주성분분석법에 의한 전산프로그램을 작성하여 분석한 결과를 요약하면 다음과 같다. 1. 해난사고의 주된 원인은 운항부주의, 기관 정비불량 등 인적요인에 있으며, 사고유형으로서는 기관고장이, 선종으로서는 어선이 특히 해난사고의 큰 비중을 차지한다. 2. 어선, 관공선의 경우에는 기관고장이나 추진기장애 등이 경미한 해난사고가 많은 경향인데 비해 화물선, 여객선, 유조선의 경우에는 좌초, 충돌, 전복, 침수 등 재산과 인명의 피해가 큰 대형해난사고가 많은 경향이다. 3. 대형해난사고 중 좌초, 충돌, 전복 등은 그 주된 원인이 운항부주의에 있고, 침수의 경우는 재질구조결함에 기인하는 바가 크다.

• Journal of Forest and Environmental Science
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• 제6권1호
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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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• 제3권1호
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• pp.41-51
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• 1986

식쌍성 TX UMa의 2색 (V와 B)의 광천측광에 의한 광도곡선(Oh and Chen 1984)을Wilson and Devinney(1971) 모델에 의한 differential corrections 방법으로 분석하였다. 그결과 TX UMa의 온도가 낮고 질량이 작은 반성은 Roche lobe를 채우고 있는 준접촉 식쌍성으로 해석된다. 한펀, 이번에 얻은 TX UMa의 측광학적 궤도요소와 Hiltner( 1945)의 분광궤도요소로부터 이 별의 절대량을 구하였다. 이에 따르면, 분광형이 B8V인 주성은 core hydrogen burning의 zero age main sequence stage에 있으며 반성은 shell hydorgen burning stage 이후 contraction stage의 진화 상태에 놓여 있는 것으로 추정된다.

• 환경영향평가
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• 제18권6호
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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.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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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.

• 대한한의학방제학회지
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• 제28권2호
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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.

• 천문학회지
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• 제48권6호
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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.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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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.

• 한국분말재료학회지
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• 제10권4호
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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.