• 제목/요약/키워드: KR

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천연물 항암제의 유도체 개발

  • 심영기
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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    • pp.212-212
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    • 1994
  • 본 연구소에서 분리하여 항암활성을 측정한바 있는 Sesquiterpene lactone계열의 KR-53170이 in vitro에 비해 in vivo에서 상대적으로 낮은 효력을 보이는데 착안 그 유도체들을 합성함으로써 in vivo stability 및 efficacy를 개선하고자 하였다. 합성된 물질의 in vivo activity는 human tumor cell중에서 A549(폐암), SK-OV-3(난소암1, SK-MEL-2(피부암), XF-498(중추신경계암), HCT-15(직장암)의 5개 암세포를 이용하여 ED$_{50}$($\mu\textrm{g}$/ml )를 측정하였으며 대조물질로는 KR-53170과 Cisplatin이 사용되었다. 그 결과 HR-53170의 terminal methyl ketone이 carboxylic acid로 변환된 CW-251001과 이것의 methyl ester인 CW-251002, ethyl ester인 CW-251003, 그리고 morpheline과 수용성으로 N-methylpiperazine, N-methyl-N'-aminopiperazine, 4-Piperidinopiperidine을 결합시켜서 합성한 CW-251011, CW-251012, CW-251013, CW-251014가 in vitro에서 어느 정도 활성을 유지하였다. 특히 이들중 CW-251001, CW-251012, CW-251013, CW-2s1014는 물에 대한 용해도가 상당히 개선되어 in vivo 활성검색을 위한 후보물질로 고려되었다. 하지만 이들중 CW-251001은 in vivo에서 낮은 농도에서는 활성이 거의 없었으며 놓은 농도에서는 독성을 나타내었다.

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Analysis of Electron Transport Coefficients in Binary Mixtures of TEOS Gas with Kr, Xe, He and Ne Gases for Using in Plasma Assisted Thin-film Deposition

  • Tuan, Do Anh
    • Journal of Electrical Engineering and Technology
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    • 제11권2호
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    • pp.455-462
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    • 2016
  • The electron transport coefficients in not only pure atoms and molecules but also in the binary gas mixtures are necessary, especially on understanding quantitatively plasma phenomena and ionized gases. Electron transport coefficients (electron drift velocity, density-normalized longitudinal diffusion coefficient, and density-normalized effective ionization coefficient) in binary mixtures of TEOS gas with buffer gases such as Kr, Xe, He, and Ne gases, therefore, was analyzed and calculated by a two-term approximation of the Boltzmann equation in the E/N range (ratio of the electric field E to the neutral number density N) of 0.1 - 1000 Td (1 Td = 10−17 V.cm2). These binary gas mixtures can be considered to use as the silicon sources in many industrial applications depending on mixture ratio and particular application of gas, especially on plasma assisted thin-film deposition.

식각액에 따른 용융실리카의 레이저 습식 식각 특성 비교 연구 (A Comparative Study on the Influence of Etchant upon the Etching Rate and Quality in Laser Induced Wet Etching of Fused Silica)

  • 이종호;이종길;전병희
    • 소성∙가공
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    • 제13권3호
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    • pp.268-272
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    • 2004
  • Transparent materials such as fused silica are widely utilized in optical and optoelectronics field because of its outstanding properties, such as transparency in a wide wavelength range, strong damage resistance for laser irradiation, and high thermal and chemical stability. In this study, we made a few micro patterns on the surface of fused silica plate using laser induced wet etching. KrF excimer laser was used as a light source. There were no burrs and micro cracks on the etched surface of fused silica and the flatness of the etched surface was fairly good. We investigated the influence of etchant upon the etch rate and quality in laser induced wet etching. Pyrene-acetone solution and toluene were used as etchant. In the side of etch rate, toluene solution was better than pyrene-acetone solution. But we made in wider range of energy density using pyrene-acetone solution. But pyrene-acetone solution gave us wider window of energy density for successful micro patterning.

A non-standard class of sobolev orthogonal polynomials

  • Han, S.S.;Jung, I.H.;Kwon, K.H.;Lee, J.K..
    • 대한수학회논문집
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    • 제12권4호
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    • pp.935-950
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    • 1997
  • When $\tau$ is a quasi-definite moment functional on P, the vector space of all real polynomials, we consider a symmetric bilinear form $\phi(\cdot,\cdot)$ on $P \times P$ defined by $$ \phi(p,q) = \lambad p(a)q(a) + \mu p(b)q(b) + <\tau,p'q'>, $$ where $\lambda,\mu,a$, and b are real numbers. We first find a necessary and sufficient condition for $\phi(\cdot,\cdot)$ and show that such orthogonal polynomials satisfy a fifth order differential equation with polynomial coefficients.

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인터넷에서 한글 메시지를 위한 전자 메일 브라우저 (E-Mail Browser for Hangul Message on Internet)

  • 이정현;임성락
    • 한국정보처리학회논문지
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    • 제5권1호
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    • pp.172-180
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    • 1998
  • 인터넷의 가장 중요한 서비스 중의 하나인 저낮 메일 시스템으 swjd보 교환의 수단으로 널리 이용되고 있다. 그러나, 대부분의 기존 전자 메일 시스템은 7비트 코드를 지원하기 위하여 설계되었기 때문에 한글 메시지와 같은 8비트 코드를 전송하는데 문제점이 있다. 이러한 문제점을 해결하기 위하여 MIME, ISO-2022-KR과 같은 기법이 발표 되었지만 아직도 한글 메시지의 송수신에는 어려움이 있다. 본 논문에서는 일반 사용자가 보다 편리하게 한글 메시지를 송수신할 수 있는 전자 메일 브라우저 모델을 제시한다. 제시한 모델의 기본 개념은 MIME만을 지원하는 POP3 클라이언트를 확장한 것으로써 8비트 한글 메시지를 ISO-2022-KR이나 Quoted-Printable 혹은 Base64로 인코딩하여 7비트로 전송한다. 제시한 모델의 타당성을 검토하기 위하여 전자 apdf 브라우저를 한글 Win95환경에서 구현하여 실험하였다.

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엑시머 레이져를 이용한 극히 얕은 접합과 소스, 드레인의 형성과 50nm 이하의 극미세 n-MOSFET의 제작 (Ultra Shallow Junction wish Source/Drain Fabricated by Excimer Laser Annealing and realized sub-50nm n-MOSFET)

  • 정은식;배지철;이용재
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.562-565
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    • 2001
  • In this paper, novel device structures in order to realize ultra fast and ultra small silicon devices are investigated using ultra-high vacuum chemical vapor deposition(UHVCVD) and Excimer Laser Annealing (ELA). Based on these fundamental technologies for the deep sub-micron device, high speed and low power devices can be fabricated. These junction formation technologies based on damage-free process for replacing of low energy ion implantation involve solid phase diffusion and vapor phase diffusion. As a result, ultra shallow junction depths by ELA are analyzed to 10~20nm for arsenic dosage(2${\times}$10$\_$14//$\textrm{cm}^2$), exciter laser source(λ=248nm) is KrF, and sheet resistances are measured to 1k$\Omega$/$\square$ at junction depth of 15nm and realized sub-50nm n-MOSFET.

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식각액에 따른 용융실리카의 레이저 습식 식각가공 (Laser Induced Wet Etching of Fused Silica according to Etchant)

  • 이종호;이종길;전병희
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2004년도 춘계학술대회 논문집
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    • pp.245-249
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    • 2004
  • Transparent materials such as fused silica are important materials in optical and optoelectronics field because of its outstanding properties, such as transparency in a wide wavelength range, strong damage resistance for laser irradiation, and high thermal and chemical stability. However, these properties make it difficult to micromachine silica in micro-sized quantities. In this study, we fabricated a micro patterns on the surface of fused silica plate using laser induced wet etching. KrF excimer laser was used as a light source. There were no burrs and micro cracks on the etched surface of fused silica and the flatness of the etched surface was fairly good. We investigated the influence of etchant upon the etch rate and quality in laser induced wet etching. Pyrene-acetone, toluene, and pyrene-toluene solution were used as etchant. In the side of etch rate, toluene and pyrene-toluene solution were better than pyrene-acetone solution.

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XML 및 SOAP 메시지 정규화 알고리즘 (Algorithm of XML and SOAP Messages Canonicalization)

  • 정회경
    • 공학논문집
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    • 제6권1호
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    • pp.125-137
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    • 2004
  • 본 논문에서는 XML과 SOAP 메시지 정규화 알고리즘을 수행하는 시스템을 설계 및 구현하였다. 따라서 더 정교하고 정규화된 문서로 변형하여 W3C 표준을 따르는 다른 응용 시스템과의 상호운용이 가능하다. 또한 웹 서비스 상호 운용성을 위한 XML 및 SOAP 메시지 교환 시 물리적 동일성이 요구되는 여러 시스템에서의 사용이 용이할 것으로 사료된다. 뿐만 아니라 국제적 인코딩 스킴과 국내 인코딩 스킴인 EUC-KR과의 변환기능을 추가함으로써 국내 실정에 맞는 XML 및 SOAP 정규화 알고리즘이 될 것이며, 이는 국제적 상호 운용성 확보의 기반 기술이 될 것이다.

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철도전문가의 성격유형과 직무만족에 관한 실증적 연구 (A Empirical Study on the Relationship between the Railway Experts' Personality types and the Work satisfaction)

  • 김충수;안준용
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2005년도 춘계학술대회 논문집
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    • pp.1-13
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    • 2005
  • Recently, The business environment is very rapidly changed and complicated. Therefore, the companies are confront with the biggest difficulty. To overcome this difficulty, the management should be able to accomplish the human resources management and the efficient business management. KR(Korea Railroad) has a close association with national life as it carries out public works based on its public nature as well as purses the corporate spirit. For that reason, KR has a great spin-off on national economy and exerts a tremendous impact on the improvement of productivity around the industries and the international competitiveness at aspect of efficiency resulting from business rationalization. Railroad system can be described as organic. Railroad Experts take a great role in this system. According the psychology and the Organization Behavior, the decision maker's personality and employee' work satisfaction have influence on performance. The purpose of this study is to examine the Railroad Experts' Personality and Work satisfaction which influence on the efficient business management.

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엑사이머 레이저를 이용한 웨이퍼 크리닝에 관한 고찰 (The Study on Wafer Cleaning Using Excimer Laser)

  • 윤경구;김재구;이성국;최두선;신보성;황경현;정재경
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 춘계학술대회 논문집
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    • pp.743-746
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    • 2000
  • The removal of contaminants of silicon wafers has been investigated by various methods. Laser cleaning is the new dry cleaning technique to replace wafer wet cleaning in the near future. A dry laser cleaning uses inert gas jet to remove contaminant particles lifted off by the action of a KrF excimer laser. A laser cleaning model is developed to simulate the cleaning process and analyze the influence of contaminant particles and experimental parameters on laser cleaning efficiency. The model demonstrates that various types of submicrometer-sized particles from the front sides of silicon wafer can be efficiently removed by laser cleaning. The laser cleaning is explained by a particle adhesion model. including van der Waals forces and hydrogen bonding, and a particle removal model involving rapid thermal expansion of the substrate due to the thermoelastic effect. In addition, the experiment of wafer laser cleaning using KrF excimer laser was conducted to remove various contaminant particles.

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