• Title/Summary/Keyword: 510(k)

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Evaluation of Inhibitory Effects of Thiobarbituric Acid Derivatives Targeting HCV NS5B Polymerase

  • Lee, Jong-Ho;Lee, Sang-Yoon;Park, Mi-Young;Ha, Hyun-Joon;Myung, Hee-Joon
    • Journal of Microbiology and Biotechnology
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    • v.20 no.3
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    • pp.510-512
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    • 2010
  • A series of thiobarbituric acid derivatives were constructed and evaluated for inhibitory activity on hepatitis C virus NS5B polymerase. In biochemical assays using purified viral polymerase and RNA template, the $IC_{50}$ value was improved to 0.41 ${\mu}M$ from the original compound's 1.7 ${\mu}M$ value. In HCV sub genomic replicon assay, the $EC_{50}$ value was improved to 3.7 ${\mu}M$ from the original compound's 12.3 ${\mu}M$ value. $CC_{50}$ was higher than 77 ${\mu}M$ for all compounds tested, suggesting that they are useful candidates for anti-HCV therapy.

Primary Renal Cell Tumors in Four Nonhuman Primates (영장류의 신장종양 발생 4례)

  • Park, Jun-Won;Jung, Iruo;Jee, Hyang;Yoo, Mi-Jin;Kim, Dae-Yong;Shin, Nam-Shik
    • Journal of Veterinary Clinics
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    • v.26 no.5
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    • pp.508-510
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    • 2009
  • Primary renal cell tumors were described in four nonhuman primates (Erythrocebus patas, Macaca cyclopis, Mandrillus sphinx, and Macaca fascicularis) that have been kept for exhibition at Seoul Zoo. Histologically, all of them were renal adenoma. Each one was clear cell type and tubular type, respectively. The rest two were papillary type adenoma. Clear cell type adenoma was bilaterally affected.

Auto-Tuning PI Control By Pattern Recognition (패턴 인식에 의한 Auto-Tuning PI 제어)

  • Park, Gwi-Tae;Lee, Gee-Sang;Kim, Sung-Ho;Park, Tae-Hong;Lee, Dong-Won
    • Proceedings of the KIEE Conference
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    • 1990.07a
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    • pp.510-513
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    • 1990
  • This paper describes the procedures for pre-tuning and re-tuning of the PI controller to specifications on patterns of output response. The key ideas of the proposed adaptive scheme are as follows. The relay feedback is adopted first for pre-tuning and the adaptive algorithms by the pattern recognition are introduced for re-tuning procedure to retune the gains whenever control conditions are changed. The proposed scheme was applied to the experimental laboratory process, heat exchanger.

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A Comparison Study on the Fire Detection Technology for Buildings and Ships (육상용과 선박용 화재감지기술의 비교연구)

  • Hong, Sung-Ho;Choi, Moon-Soo;Lee, Sang-Ho;Park, Sang-Tae;Yoo, Song-Hyun
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2011.11a
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    • pp.510-513
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    • 2011
  • 본 논문은 육상에서 사용되는 화재감지기술과 선박에서 사용되는 화재감지기술의 차이점과 육상용과 선박용 화재감지기 성능시험방법을 비교한 연구이다. 화재감지기술은 비화재보나 오동작을 개선하는 방향으로 발전해 왔다. 육상용 화재감지기는 건물에서 통상적으로 발생할 수 있는 비화재보 요인에 의한 비화재보나 오동작을 방지할 수 있어야 하고, 선박용 화재감지기의 경우에는 염분이 높은 환경에서 사용되는 특성상 염분에 의해 화재감지기가 오동작 또는 비화재보를 발생시키지 않는 구조로 설계되어야 한다. 본 연구에서는 건물에 설치되는 육상용 화재감지기의 최신 발전 방향을 소개하고 선박에서 발생할 수 있는 화재를 조기에 감지할 수 있는 화재감지기술을 고찰하였다.

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CORRELATION BETWEEN THE TENSILE STRENGTH AND CORROSION BEHAVIOR OF HEAT TREATED ZR-1.0NB ALLOY

  • Kim, Tae-Kyu;Choi, Pyung-Sik;Yang, Sung-Ki;Lee, Chong-Tak;Sohn, Dong-Seong
    • Nuclear Engineering and Technology
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    • v.40 no.6
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    • pp.505-510
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    • 2008
  • The correlation between the tensile strength and corrosion behavior of Zr-1.0wt%Nb alloy heat treated at $480^{\circ}C$ for up to 32 hours was evaluated. The tensile strength at $400^{\circ}C$ was continuously reduced with an increasing heat treatment time, mainly due to a grain growth and a decreased area fraction of the precipitates. However, the corrosion resistance in an aqueous ammonia solution at $360^{\circ}C$ was enhanced, mainly due to the formation of $\beta$-Nb precipitates. It is thus concluded that a longer heat treatment time provides a better corrosion resistance while degrading the tensile strength.

The Crystal and Molecular Structure of 1-(Hexahydro-1H-azepin-1-yl)-3-(p-tolylsulfonyl) Urea: Tolazamide ($C_{14}H_{21}N_3O_3S$)

  • Koo, Chung-Hoe;Suh, Jung-Sun;Yeon, Young-Hee;Watanabe, Tokunosuke
    • Archives of Pharmacal Research
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    • v.11 no.1
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    • pp.74-79
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    • 1988
  • Crystals of tolazamide, $C_{14}H_{21}N_3O_3S$, are triclinic space group $P{\bar{1}}$ with cell dimensions of a = 6.355 (2), b = 9.223 (2), c = 13.510 (3) A, ${\alpha}\;=\;101.04\;(8),\;{\beta}=92.80(5),\;{\gamma}\;=\;85.72\;(6)^{\circ}$ and Z = 2. Intensities were collected on an automated four-circle diffractometer using graphite-monochromated Cu K ${\alpha}$ radiations. The structure was solved by direct method and refined by full-matrix least-squares to an R factor of 0.058 for 1184 observed reflections. The molecules are dimerized by the $N-H{\cdots}O$ hydrogen bonds. There are only van der Waals interactions between these molecular dimers.

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Color volumetric 3D display system based on a rotating LED Screen

  • Haifeng, Li;Jiang, Wu;Xu, Liu;Caijie, Yan;Zhenrong, Zheng
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.510-512
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    • 2009
  • A volumetric 3D display system based on a rotating two dimensional color LED array is set up. It has a cylinder display space ${\Phi}800{\times}640mm3$ which is composed of 256 slices of pictures in one 3D image with each slice $320{\times}256$ LED pixels. The volumetric image has 4 gray scales and 64 colors. The main structure and working principle of the system is described in detail.

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Modeling and Steady-state Analysis of the Multi-Phase Interleaved Buck converter in Discontinuous Inductor Current Mode (불연속 전류모드에서의 다상 교호 강압컨버터의 정상상태 해석 및 모델링)

  • Chang, Sung-Dong;Jang, Eun-Sung;Chung, Se-Kyo;Shin, Hwi-Boem;Lee, Hyun-Woo
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.05a
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    • pp.506-510
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    • 2004
  • A multi-phase interleaved buck converter is used to reduce current ripples and filter size of a power supply. This paper addresses the modelling and steady-state analysis of the multi-phase interleaved buck converter operated in discontinuous inductor current mode. The model is derived using an averaging technique in steady state. The do voltage ratio and the range of the discontinuous inductor current mode(DICM) and the continuous output current mode(COCM) are derived from the averaged state-space model. In addition, the efficiency is investigated according to the number of phase.

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Energy efficient PNC selection procedure for HR-WPAN (HR-WPAN을 위한 에너지 효율적인 PNC 선택 절차)

  • Han, Jin-Woo;Yoo, Dae-Hun;Choi, Woong-Chul;Rhee, Seung-Hyong;Chung, Kwang-Sue
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.07a
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    • pp.508-510
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    • 2005
  • IEEE 802.15.3에서 piconet 안의 PNC가 선택되는 방법은 각각 디바이스들의 능력을 기반으로 선택 된다. 이러한 PNC의 역할을 하는 디바이스는 piconet안에서 가장 많은 에너지를 소비하게 된다. PNC의 프레임 전송 범위는 PNC 에너지 소비와 밀접한 관련을 가지고 있다. 그래서 PNC역할을 하는 디바이스를 토폴로지 상의 중앙에 위치 시켜서 PNC의 프레임 전송 거리를 최소화한다. 이를 통해 PNC의 에너지를 절약하여 PNC역할을 하는 디바이스의 생존 시간을 연장 시키고자 한다. 본 논문에서는 이러한 PNC의 전송범위를 최소화 할 수 있는 piconet 토폴로지상의 위치를 정하는 방법에 대하여 제안하고 있다.

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