• Bulletin of the Korean Chemical Society
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• 제32권9호
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• pp.3219-3222
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• 2011

Three types of ${\beta}$-ketoacyl acyl carrier protein synthase (KAS) are important for overcoming the bacterial resistance problem. Recently, we reported the discovery of a antimicrobial flavonoid, YKAF01 (3,6-dihydroxyflavone), which exhibits antibacterial activity against Gram-positive bacteria through inhibition of ${\beta}$-ketoacyl acyl carrier protein synthase III (KAS III). In this report, we suggested that YKAF01 can be an inhibitor ${\beta}$-ketoacyl acyl carrier protein synthase I (KAS I) with dual inhibitory activity for KAS I as well as KAS III. KAS I is related to the elongation of unsaturated fatty acids in bacterial fatty acid synthesis and can be a good therapeutic target of designing novel antibiotics. We performed docking study of Escherichia coli KAS I (ecKAS I) and YKAF01, and determined their binding model. YKAF01 binds to KAS I with high binding affinity ($2.12{\times}10^6$) and exhibited an antimicrobial activity against the multidrug-resistant E. coli with minimal inhibitory concentration (MIC) value of 512 ${\mu}g$/mL. Further optimization of this compound will be carried out to improve its antimicrobial activity and membrane permeability against bacterial cell membrane.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1645-1649
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• 2011

[ ${\beta}$ ]Ketoacyl acyl carrier protein synthase I (KAS I) is involved in the elongation of unsaturated fatty acids in bacterial fatty acid synthesis and a therapeutic target of designing novel antibiotics. In this study, we performed receptor-oriented pharmacophore-based in silico screening of E. coli KAS I (ecKAS I) with the aim of identifying novel inhibitors. We determined one pharmacophore map and selected 8 compounds as candidates ecKAS I inhibitors. We discovered one antimicrobial compound, YKAe1008, N-(3-pyridinyl) hexanamide, displaying minimal inhibitory concentration (MIC) values in the range of 128-256 ${\mu}g/mL$ against MRSA and VREF. YKAe1008 was subsequently assessed for binding to ecKAS I using saturation-transfer difference NMR spectroscopy. Further optimization of this compound will be carried out to improve its antimicrobial activity and membrane permeability against bacterial cell membrane.

• 복식
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• 제40권
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• pp.25-35
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• 1998

This thesis is a study of Kas ya, robes of buddhist monk, which is having peculiarity among human clothes. I kept my attention mainly on the symbolism of the color of Kas ya. To elucidate this, I chose the principle of T -chi and Yin-yang and Wu-shing as a frame-work of interpretation. In the first place, the original meaning of Kas ya mean a name of peculiar color. The concrete names of the color are color of persimmons juice, brown, yellow tinged with red, radish brown, non-primary color etc. The main motive to dye three robes of buddhist monk from white or primary color to the color of Kas ya was to differentiate buddhist monks from heathen or laymen. Therefore, as luxurious and primary colored cloths was donated to the buddhist monks, they are necessary to discolor them. Accordingly. they established 'non-primary color' as well-mate one for a ascetic. The non-primary color is called discolored color' as a result of discoloring primary colors. The discolored color is a synonym of Kas ya and the process of discoloring is necessary for making robes of buddhist monk. Secondly, discoloring means to mash five primary color. That is say, the process of discoloring means to return five primary colors back to 'profoundity·abstruseness·obscurity, namely darkness' as the source of them. Darkness as a condition amalgamated and not appeared all materials is the source and at the same time the terminus of all colors. Therefore, color of Kas ya symbolizes 'profound color' as the ultimate meaning of discoloring. Thirdly, discoloring garments of buddhist monk symbolize to destroy evil passions and haughtiness arising in ascetic's mind as well as means don't attach to the shaped materials'. Fourthly, discoloring means to return 'color'. namely 'all kinds of shaped material' to the inherent nature. Process of discoloring means to reture to the empty. nya. nya essentially do not make any colors, but over and over again come into being and become extinct as becoming colors. R pa, by one time Yin and the other time Yang'. R pa, color is a metaplasia of nya and nya is discoloring one of all colors. Then, discoloring means R pa is nya, R pa is nya at the same time and Because this is another expression of Dharma the original meaning of Kas ya symbolize true robes. Consequently, Kas ya means truth and beyond time and space do not be changed and conserve the color of the first till now.

• Applied Biological Chemistry
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• 제49권3호
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• pp.192-195
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• 2006

국내에서 개발된 비타민 E 강화 유전자변형 들깨의 정성 PCR 분석법의 개발을 위해 들깨의 내재 유전자로써 KAS-I (Beta-ketoacyl-ACP synthase I)를 선별하였고, 이러한 내재유전자를 특이적으로 증폭시킬 수 있는Primer(Pfru3-F/R)쌍을 이용한 PCR에서 95 bp의 PCR증폭 산물을 얻었으며, 들깨를 포함한 16개 작물에 대해 PCR을 수행한 결과에서 들깨만이 특이적으로 증폭되는 것을 확인하였다. 또한, 비타민 E 강화 유전자변형 들깨에 삽입된 TMT(${\gamma}$-tocopherol methyltransferase) 유전자와 OCS(Octopine synthase) terminator 연결 부위를 증폭시켜 148 bp의 PCR 산물을 얻을 수 있는 primer(TMTO-F/R)를 제작하였으며, 이러한 두 쌍의 primer를 이용하여 국내 개발된 비타민 E 강화 유전자변형 들깨의 PCR 정성 분석법을 확립하였다.

• 환경위생공학
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• 제21권1호
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• pp.21-34
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• 2006

To investigate anti-HIV-1 activity of water soluble chitosans, sulfated chitosan derivatives were prepared in mild condition. Various sulfated chitosan derivatives (N-3,6-O-S-chitosan, N-desulfated 3,6-O-S-chitosan, 3,6-O-S-chitin, and 3,6-O-sulfated-N-(o-carboxybenzoyl) chitosan) were synthesized with sulfurtrioxidepyridene complex in pyridine solvent. Characterization of the sulfated chitosan derivatives was carried out by $^{13}C$ NMR and IR spectroscopies. To observe ionic reaction properties, pKas of the sulfated chitosan derivatives and chitosan of low molecular weight were estimated by potentiometric titration. The sulfated chitosan derivatives had high water solubility, pKas (pKa : 7.7) of N-3,6-O-S-chitosan and N-desulfated 3,6-O-S-chitosan were increased than pKa of water insoluble chitosan (pKa : 6.2), These results suggest the participation of electrostatic interaction of amino and sulfate groups on the sulfated chitosans. Anti-HIV-1 drugs, such as AZT, ddC, and ddI for anti-HIV activity had higher selective index compared with SCB-chitosan but N-3,6-O-S-chitosan has shown higher selective index compared with ddC and ddI as HIV drugs.. These results suggest that sulfated chitosan derivatives were expected as an anti-HIV drug with differential driving force mechanism against some nucleoside analogs drug in the future.

• 한국항공우주학회지
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• 제46권8호
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• pp.694-701
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• 2018

현재 항공기 민수인증분야에서 국제적으로 사용하고 있는 항공기 소음인증기준인 ICAO Annex 16 Vol. I에서는 항공기의 종류에 따라 A-Weighted SPL, EPNL, SEL 계산법을 사용하고 있다. 우리나라를 포함한 미국, 유럽도 이를 기반으로 항공기 소음인증기준을 개발하여 사용하고 있으며, KAS 36, CS 36, FAR 36 기준이 모두 동등하고 제한 값은 동일하다. 소형 항공기의 경우에는 이륙소음 한계만 규정하고 있으며, dB(A) 단위의 A-Weighted SPL 계산법을 사용하고 있다. 국내에서는 2012년 8월에 KC-100 항공기에 대하여 소음인증을 최초로 수행한 바 있으며, 당시 FAA와 함께 KAS 36과 FAR 36 해당 기준을 동시에 만족하는지 시험평가 되었다. 소음인증시험의 경우 시험조건과 처리방법이 까다로워 많은 경험과 배경지식이 필요하다. 이에 KC-100 인증비행시험을 기반으로 소형비행기의 소음인증 기준 분석과 시험조건 및 데이터 처리방법을 실 인증사례를 바탕으로 제시하고자 한다.

• 천문학회보
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• 제44권1호
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• pp.57.3-57.3
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• 2019

Recently, there have been discussions among national observatories in East Asia about the possibility of EAO and the Subaru observatory forming a partnership. The official EAO-Subaru partnership can make the powerful wide-field observation capabilities of Subaru available to Korean astronomers through EAO, and also can serve as an excellent platform to gather astronomers in East Asia together for flourishing regional collaboration activities. A working group has been formed to outline the framework of the EAO-Subaru partnership, and the working group report has been prepared. In this talk, I will explain the proposed partnership framework in the working group report. Inputs are very welcome from KAS members about the proposed framework.

• 한국실내디자인학회논문집
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• 제25호
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• pp.176-183
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• 2000

The purpose of this study is to show the implications of the term "digital architecture," which are realized in the current architecture. To do this, I first observe its theoretical background and then analyze the works of Marcos Novak, Kas Oosterhuis, and Lars Spuybroek, all of whom are called the typical digital architects. In particular, this study tries to show that the digital architects are introducing the non-Euclidean multi-dimensions and the cyberspace and applying the notions of liquid architecture, transarchitecture, body-building, and body-building, and body-motorized system into their works. Finally, I conclude that the digital architecture anticipates the direction of the future architecture, in which the virtual world is merged with the real world, the digital space is realized in the real space, and the human is completely harmonized with nature.th nature.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 추계학술대회 논문집 학회본부
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• pp.95-98
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• 1996

Response speed of generator/control system kas increased with the aid of the development of power electronics. Even though it is desirable to enhance response speed for the control system(AVR/Gov) of generator itself, in case a certain generator/control system with high response excitation system is connected with bulk power system, terminal voltage and active power of some generators can oscillate with adjoining generators or near area when even a little of disturbance take place. PSS(Power System Stabilizer) is used to damp rotor swing by adding the supplementary signal in phase with speed. As the stable AVR response is very important before PSS is installed, modeling and analysis of generator/control system was performed. Next we have analysed PSS response of Hanlim's gas turbine by transmission line open/close test.

• 한국토양비료학회지
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• 제16권1호
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• pp.42-49
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• 1983

토양(土壤)의 가리공급력(加里供給力)에 따른 시비량(施肥量) 추정(推定)에 활용(活用)하기 위(為)하여 수도(水稻)의 출수기(出穗期) 및 시험전(試実前) 토양(土壤)의 Q/I관계(関係)에서 Potential Buffering Capacity($PBC^K$)와 ${\delta}K$ = 0 일 때의 가리활동도비(加里活動度比) $[K^+/{\sqrt{Ca^{{+}{+}}+Mg^{{+}{+}}}:m/{\ell}]:AR^K_o$, 및 상대가리(相対加里) 활성도비(活性度比) Kas/Kai를 구(求)하고 이들 요인(要因)의 상호관계(相互関係)와 이들 요인과 수도(水稻)의 가리흡수량(加里吸收量) 및 정조수량(正租收量)과의 관계(関係)를 비교(比較) 검토(検討)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 항온처리기간중(恒溫処理其間中)(67일간(日間)) 비치환성가리(非置換性加里)가 치환성가리(置換性加里)로 변화(変化)되는 양(量)이 거의 없었으므로 시험전(試験前) 토양(土壤)의 가리공급력(加里供給力)은 주(主)로 치환성가리(置換性加里)의 함량(含量)에 의(依)하여 지배(支配)된다고 판단(判断)되였다. 2. 시험전(試験前) 토양(土壤)의 Q/I 관계(関係)에서 조사(調査)된 $PBC^K$는 식양토(埴壤土) 0.027, 양토(壤土) 0.014 사양토(砂壤土) 0.009 (${\frac{me/100g}{m/{\ell}}}$)이며 $AR^K_o$는 식양토(埴壤土) $9.1{\times}10^{-3}$ 양토(壤土) $7.6{\times}10^{-3}$ 사양토(砂壤土) $15.4{\times}10^{-3}(m/{\ell})$으로 토성(土性)에 따라 차이(差異)가 있었다. 3. 출수기(出穗期) 토양(土壤)에서 조사(調査)된 가리성분(加里成分)의 완충능(緩衝能), $PBC^K$를 시험전(試験前) 토양(土壤)의 그것과 비교(比較)할때, 토성(土性)과 시비수준(施肥水準)에 관계없이 비교적(比較的) 안정적(安定的)였음으로 가리(加里)의 공급력(供給力)이나 경토(耕土)의 개량가부(改良加否)에 활용(活用)될 수 있을 것으로 판단(判断)되었다. 4. 출수기(出穗期) 토양(土壤)의 $AR^K_o$는 그 값이 가리시용량(加里施用量)에 관계(関係)없이 가리(加里) 무시용시(無施用時) $AR^K_o$값과 일치(一致)하는 경우(境遇)에 가리증시(加里增施)에 따른 벼 증수(增收)가 현저(顕著)하였다. 5. 출수기(出穗期) 토양(土壤)의 Q/I 관계(関係)에서 조사(調査)된 $PBC^K$와 $AR^K_o$는 단독적(単独的)으로 사용(使用)보다 복합적(複合的)으로 사용(使用)할 때 가리흡수량(加里吸收量) 및 정조수량(正租收量) 공(共)히 상관(相関)이 높았다. 6. 시험전(試験前) 토양(土壤)의 Kas/Kai 추정치(推定値)와 출수기(出穗期) 토양(土壤)의 $AR^K_o$과는 높은 상관(相関)을 보여 서로 유사(類似)한 토양(土壤) 화학적(化学的) 요인(要因)으로 판단(判断)되며 가리시비량(加里施肥量) 추정(推定)에 활용(活用)될 수 있는 가능성(可能性)을 보였다.