• Title/Summary/Keyword: Gil-ho Kim

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Clamp-type Bulk Optic Current Sensor (클램프헝 부피 광 전류센서)

  • Chung, Hyun;Lee, Yong-Wook;Kim, Soo-Gil;Lee, Byoung-Ho;Park, Byoung-Seok
    • Proceedings of the KIEE Conference
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    • 2002.07c
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    • pp.1924-1926
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    • 2002
  • The optical current transformer using Faraday effect is the sensor to measure current that flows in any conductor. This sensor doesn't undergo the magnetic saturation and effect of adjacent conductors. But this senor using bulk-glass sensing clement has crucial drawback. It is impossible that the sensor is mounted to conductor without breaking the closed-loop of light or conductor. So we developed the clamp-type optical current transformer and made an experiment.

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Switching Characteristics Enhancement of PT Type Power Diode using Proton Irradiation Technique (양성자 주입기술을 이용한 PT형 전력다이오드의 스위칭 특성 향상)

  • Kim Byoung-Gil;Choi Sung-Hwan;Lee Jong-Hun;Bae Young-Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.19 no.3
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    • pp.216-221
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    • 2006
  • Lifetime control technique by proton implantation has become an useful tool for production of modern power devices. In this work, punch-through type diodes were irradiated with protons for the high speed power diode fabrication. Proton irradiation which was capable of controlling carrier's lifetime locally was carried out at the various energy and dose conditions. Characterization of the device was performed by current-voltage, capacitance-voltage and reverse recovery time measurement. We obtained enhanced reverse recovery time characteristics which was about $45\;\%$ of original device reverse recovery time and about $73\;\%$ of electron irradiated device reverse recovery time. The measurement results showed that proton irradiation technique was able to effectively reduce minority carrier lifetime without degrading the other characteristics.

A study on the tool deflection shape using high speed camera (고속카메라를 이용한 공구 절입시 변형 형상에 관한 연구)

  • Kim, Kun-hee;Jung, Woo-chul;Yoon, Gil-sang;Sin, Kwang-ho;Heo, Yeong-mu
    • Design & Manufacturing
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    • v.2 no.1
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    • pp.27-31
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    • 2008
  • The object of this study is a manufacture of buff die using CAM systems. Systems are consist of AutoCAD, CAM software and CNC milling machine. CAM software is purpose of G-code generation for CNC programming. Then CAM software and CNC milling machine are connect to RS-232-C cable for networking.

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Swelling and Thermal Properties of Crosslinked Poly(2-Hydroxyethyl Methacrylate) Hydrogels (가교된 폴리(2-히드록시에틸 메타크릴레이트)수화겔의 팽윤성 및 열적 성질)

  • Seong, Yong-Gil;Nam, Gi-Ho;Kim, Gye-Yong
    • Journal of Biomedical Engineering Research
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    • v.8 no.1
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    • pp.13-28
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    • 1987
  • Crosslinked poly(2-hydroxyethylmethacrylate) has been prepared by polymerizing 2-hydroxyethyl methacrylate(HEMA) with crosslinkers such as ehyleng glycol dime- thacrylate(EGDMA), tetraethylene glycol dimethacrylate(TEGDMA), tetraethylene glycol diacrylate(TEGDA), divinyl benzene(DVB), and N, N-methylenebisacry- lamide(MAB) in the presence of initiator $\alpha$ , $\alpha$ -azobisisobutyronitrile at 60。C, The synthesized copolymers were identified by FT-lR spectrophotomether. The swelling properties of the crosslinked copolymers in various solvents such as water, methanol, ethanol, n-propanol, and n-butanol were investigated at different temperatures. The thermal properties of the crosslinked coplymers were also measured by differential scanning calorimetry(DSC) and thermogravimetry(TG)

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AC-PDP에서 지속방전으로 재형성 된 MgO 나노 입자의 음극선 분광 분석

  • Lee, Gyeong-Ae;Choe, Jun-Ho;Kim, Yong-Hui;Son, Chang-Gil;Choe, Eun-Ha
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.109-109
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    • 2010
  • 최근 AC-PDP에서 MgO Protective Layer 위에 별도의 기능막(Functional Layer)을 사용하고 있는데, 이 기능막인 MgO 나노 입자는 장시간 구동시 AC_PDP panel내에서 plasma 방전에 의하여 MgO Protective Layer와 기능막이 방전 공간에 형성 된 이온에 의해 Sputtering 또는 재 증착 될 수 있다. 본 실험에서는 조성이 다른 기능막이 적용된 AC-PDP Test panel을 제작하여 장시간 구동 후 기능막인 두 가지 다른 MgO 나노 입자의 재형성된 형태를 주사 전자 현미경(Scanning Electron Microscope)을 통해 Surface Profile 및 구조의 변화를 분석하고, 또한 음극선 분광 분석(Cathodoluminascence)을 통하여 방전 영역과 비방전 영역의 delay time, 방전전압 및 효율 등의 전기 광학적 특성과의 관계를 분석하고자 한다.

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A Case of Sarcomatoid Carcinoma of the Larynx Mimicking Vocal Polyp (성대 폴립으로 오인된 후두의 육종양 암종 1례)

  • Kim, Taehoon;Lee, GilJoon;Sohn, Jin Ho
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.28 no.2
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    • pp.128-130
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    • 2017
  • Sarcomatoid carcinomas are biphasic tumors which have surface epithelial changes and an underlying spindle-shaped neoplastic proliferation. A 62-year-old male with hoarseness came to our hospital for evaluation. A single smooth polypoid lesion was detected on his right true vocal fold by larnygoscope. The patient was diagnosed with vocal polyp and treated with surgical excision. Pathology report of the excised specimen was compatible with sarcomatoid carcinoma. Therefore, further surgical resection was performed to secure safety margins. We report a case of a sarcomatoid carcinoma patient who was clinically diagnosed as vocal polyp.

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Brackish Lakes in Shinpo District North Korea. III. Fish

  • Gil, Joon-Woo;Hong, Young-Pyo;Park, Joon-Ho;Kim, Saywa
    • Proceedings of the Korea Society of Environmental Biology Conference
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    • 2004.05a
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    • pp.23-23
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    • 2004
  • Four times of field survey were carried out to collect fish samples at six stations in Shinpo district, North Korea in October 1997, July 1998, May and October 2002. Sampling stations were located in upstream, middle and down of the southern river of Bukchong and three brackish lakes of lake Hommanpo, Daein and Hyunkum, respectively. A total of 29 species belonging to 11 families occurred. Family Cyprinidae showed the prosperity in species number of 28% among total species occurred. No natural monument fishes or rare species were captured. Ten commercial fishes, five anadromous ones and five brackish ones were identified. Feeding habits divided fish fauna with 11 carnivores, two herbivores and seven omnivorous ones. In the river, 20 species belonging to seven families inhabited, 18 species of 6 families in lake Homanpo, 21 of seven III Hyunkum and 23 of eight in Daein, respectively. Ecological indices of richness, diversity and evenness were highest in lake Daein and dominance index was highest in lake Hyunkum.

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BAYESIAN INFERENCE FOR FIELLER-CREASY PROBLEM USING UNBALANCED DATA

  • Lee, Woo-Dong;Kim, Dal-Ho;Kang, Sang-Gil
    • Journal of the Korean Statistical Society
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    • v.36 no.4
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    • pp.489-500
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    • 2007
  • In this paper, we consider Bayesian approach to the Fieller-Creasy problem using noninformative priors. Specifically we extend the results of Yin and Ghosh (2000) to the unbalanced case. We develop some noninformative priors such as the first and second order matching priors and reference priors. Also we prove the posterior propriety under the derived noninformative priors. We compare these priors in light of how accurately the coverage probabilities of Bayesian credible intervals match the corresponding frequentist coverage probabilities.