• Title/Summary/Keyword: 510(k)

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Nanofiller as Crosslinker for Halogen-Containing Elastomers

  • Sahoo, N.G.;Kumar, E.Shiva;Das, C.K.;Panda, A.B.;Pramanik, P.
    • Macromolecular Research
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    • v.11 no.6
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    • pp.506-510
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    • 2003
  • A Zn ion-coated nanosilica filler has been developed and tested, in chlorosulfonated polyethylene (CSPE) and polychloroprene (CR), as a vulcanizing activator, cum was reinforcing filler. In this study, ZnO was replaced by the Zn ion-coated nanosilica filler with an aim of studying the dual role of this nanofiller in CSPE and CR. In the case of CSPE vulcanizates, the presence of MgO deteriorated the state and rate of cure when the Zn ion-coated nanosilica filler was used, but in the case of CR it improved the state of cure and enhanced the modulus and tensile strength. The Zn ion-coated filler proved to be a better reinforcing-cum-curing agent than was externally added ZnO and NA-22 also proved to be a better curative in the presence of the Zn ion-coated nanosilica filler for both CSPE and CR.

Laboratory Surveillance of Influenza B Epidemic in Seoul During the Winter of 1985-1986 (서울에서의 인플루엔자 B바이러스 유행감시, 1985-1986)

  • Park, Kee-Duk;Cho, Yang-Byuk;Kim, Young-Sun;Paik, Seung-Bok;Keum, Dong-Hyuk;Shin, Mee-Ja
    • The Journal of the Korean Society for Microbiology
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    • v.22 no.1
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    • pp.9-13
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    • 1987
  • During 31 days (5 week) from December 9th 1985 to January 8th 1986, Influenza B epidemic were observed in Seoul city. Epidemic peak was shown at 52nd week in 1985. The Epidemic associated viruses were determined as B/yamanish/510/84 and B/Ann Arbor/1/86-like strain. From total of 124 specimens of influenza-like illness children virus isolation rate were average 4.0%, much lower than that of influenza A virus isolation experience. In the epidemic influenza B infection were predominantly involved in school age children.

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The Properties of the Inductive Coupler for Power Line Communications as Nano Magnetic Materials (나노 자성 재료를 이용한 PLC용 비접촉식 커플러의 특성 향상 연구)

  • Kim, Hyun-Sik;Lee, Hae-Yeon;Kim, Jong-Ryung;Lee, Jun-Hui;Oh, Young-Woo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.346-346
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    • 2009
  • 저손실 고투자율 특성을 갖는 $\alpha$-Fe 나노결정 자심재료를 제조하기 위해 열처리 온도를 변화시켰으며 투자율과 신호전송 특성을 측정한 결과 $510^{\circ}C$에서 열처리된 자심재료에서 가장 우수한 특성을 얻었다. 저주파 대역에서의 신호전송 특성은 자심재료의 자기적 특성에 지배적인 영향을 받으며, 고주파 대역의 신호전송 특성은 임피던스 매칭으로 향상시킬 수 있었다. 에어-캡은 $500{\mu}m$ 이상 적용할 때, 100 A이상까지 안정적인 특성을 발휘하였다. 그리고 고역통과 필터의 설계와 신호결합장치에의 적용을 통해 통신대역 이외의 노이즈를 제거할 수 있었다.

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Analysis of Lighting Overvoltage and Induced Voltage of Neutral Line on the 22.9kV Combined Distribution Line (22.9kV 혼합배전선로의 뇌과전압 해석 및 중성선 유기 전압 해석)

  • Hong, Dong-Suk;Lee, Jong-Beom
    • Proceedings of the KIEE Conference
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    • 2000.07a
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    • pp.510-512
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    • 2000
  • This paper describes the voltage induced at neutral line and the proper location of lightning arrester in combined 22.9 kV class distribution line jointed overhead line and cable each other Modeling is established in ATP Draw to perform simulation. Simulated distribution line at this paper consists of distribution line 4.2km and underground distribution line 2km. Overvoltage and induced voltage are analyzed at several point of combined line. Analysis results was compared to select the best point to install arrester. Such analysis technology will be applied to obtaining capacity and location of arrester in the similar combined distribution line.

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Performance analysis of Various Embedding Models Based on Hyper Parameters (다양한 임베딩 모델들의 하이퍼 파라미터 변화에 따른 성능 분석)

  • Lee, Sanga;Park, Jaeseong;Kang, Sangwoo;Lee, Jeong-Eom;Kim, Seona
    • Annual Conference on Human and Language Technology
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    • 2018.10a
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    • pp.510-513
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    • 2018
  • 본 논문은 다양한 워드 임베딩 모델(word embedding model)들과 하이퍼 파라미터(hyper parameter)들을 조합하였을 때 특정 영역에 어떠한 성능을 보여주는지에 대한 연구이다. 3 가지의 워드 임베딩 모델인 Word2Vec, FastText, Glove의 차원(dimension)과 윈도우 사이즈(window size), 최소 횟수(min count)를 각기 달리하여 총 36개의 임베딩 벡터(embedding vector)를 만들었다. 각 임베딩 벡터를 Fast and Accurate Dependency Parser 모델에 적용하여 각 모들의 성능을 측정하였다. 모든 모델에서 차원이 높을수록 성능이 개선되었으며, FastText가 대부분의 경우에서 높은 성능을 내는 것을 알 수 있었다.

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Growth and upconversion properties of erbium doped $LiNbO_3$ single crystal fibers ($Er^{3+}$ 첨가 $LiNbO_3$ fiber 단결정의 성장 및 upconversion 특성)

  • Yang, Woo-Seok;Suh, Su-Jeong;Lee, Jong-Ho;Tsuguo Fukuda;Yoon, Dae-Ho
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1999.06a
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    • pp.321-335
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    • 1999
  • Erbium(Er) doped LiNbO3(Er:LiNbO3) single crystal gibers were grown free of cracks along the c-axis by micro-pulling down method. the Er3+ concentration was distributed homogeneously along the growth axis. The samples for optical characterization were cut from as-grown single crystal fibers and polished. When the 980 nm light was incident on the sample, upconversion phenomena were observed at the green range of wavelength 510~570 nm. In addition, the intensity of upconversion was remarkably increased by increasing the concentration of Er2O3 dopant in as-grown Er:LiNbO3 crystals.

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Growth and upconversion properties of erbium doped $LiNbO_{3}$ single crystal fibers

  • Yang, Woo-Seok;Suh, Su-Jeong;Lee, Jong-Ho;Fukuda, Tsuguo;Yoon, Dae-Ho
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.9 no.4
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    • pp.377-380
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    • 1999
  • Erbium (Er) doped $LiNbO_{3}(Er:LiNbO_{3})$ single crystal fibers were grown free of creacks along the c-axis by micro-pulling down method. The $Er^{3+}$ concentration was distributed homogeneously along the growth axis. The samples for optical characterization were cut from as-grown single crystal fibers and polished. When the 980nm light was incident on the sample, upconversion phenomena were observed at the green range of wavelength 510~570nm. In addition, the intensity of upconversion was remarkably increased by increasing the concentration of $Er_{2}O_{3}$ dopant in as-grown $Er:LiNbO_{3}$ crystals.

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A Study on Dielectric Properties of PCW-PNN-PZT ceramics (PCW-PNN-PZT계 세라믹의 유전 특성에 관한 연구)

  • Shin, Hye-Gyeong;Lee, Sung-Ho;Jung, Bo-Ram;Bae, Seon-Gi
    • Proceedings of the KIEE Conference
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    • 2005.11a
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    • pp.51-53
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    • 2005
  • This study was to measure the minuteness structure, dielectric properties of 0.03PCW-0.07PNN-0.9PZT ceramics according to sintering temperature manufacture the specimens with a general method. The results of this study were gotten such as follows. The crystal structure of ceramic changed the rombohedral structure into teteragonal structure according to rising sintering temperature in XRD. Dielectric constant at $20^{\circ}C$ showed its maximum value 510.599 in specimens sintered at $1100^{\circ}C$ and dielectric loss showed its minimum value 7.43% in specimens sintered at $1100^{\circ}C$. The variation rate of dielectric constant according to the change of frequency showed its minimum value 0.029/kHz at $1100^{\circ}C$. The variation rate of dielectric constant according to the change of temperature showed its minimum value $1.40/^{\circ}C$ at $1500^{\circ}C$.

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A Study on the Power Monitoring System Based on the PLC (PLC를 이용한 전력감시시스템 개발에 관한 연구)

  • Lee, Soo-Yong;Wang, Jong-Yong;Oh, Young-Dae;Kim, Chan-Hyeok;Rho, Dae-Seok
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.510-511
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    • 2008
  • 전력 시스템은 인간이 만든 시스템 가운데 가장 크고 복잡한 시스템이다. 현대 디지털 경제 사회의 인프라는 전력시스템을 통한 전기에너지의 공급과 기술에 기초하고 있다. 전력시스템은 대용량화, 대규모화, 고 효율화를 위한 시설증대와 기술개발로 이루어져 있다. 사람이 직접 사고 현장을 가지 않고 컴퓨터로 제어함으로써 사람의 번거로움을 기계가 대신해 줌으로서 사람의 생활을 보다 편리하며 효율성 측면에서도 기여함에 틀림이 없는 사실이다. 따라서 디지털 정보화 사회에서 언제 어디서나 인간과 설비들이 컴퓨터와 통신네트워크에 의해 접속되는 유비쿼터스화 사회의 에너지와 정보통신 인프라 역할로 새롭게 전환 될 수 있음을 인식하는 전력감시시스템을 PLC 기술을 이용하여 저렴하게 구현하였다.

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