• Title/Summary/Keyword: BEA

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Polysilicon Thin Film Transistor for Improving Reliability using by LDD Structure

  • Jung, Eun-Sik;Jang, Won-Su;Bea, Ji-Chel;Lee, Young-Jae
    • Proceedings of the IEEK Conference
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    • 2002.07b
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    • pp.1050-1053
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    • 2002
  • In this paper, Amorphous silicon on glass substrate was recrystallized to poly-crystalline silicon by solid phase crystallization (SPC) technology. The active region of thin film transistor (TFT) was fabricated by amorphous silicon. The output and transfer characteristics of thin film transistor with lightly doped drain (LDD) structure was measured and analyzed. As a results, analyzed TFTs reliability with LDD's length by various kinds argument such as sub-threshold swing coefficient, mobility and threshold voltages were evaluated. Stress effects in TFT were able to improve to the characteristics of turn-on current and hot carrier effects by LDD's length variations.

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Verification Test for Primary Reactor Piping in Nuclear Power Plant (원자로 주 배관계의 진동 건전성 시험)

  • Kim, Yeon-Whan;Kim, Hee-Su;Koo, Jae-Raeyang;Bea, Yong-Chae;Lee, Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.315.1-315
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    • 2002
  • The piping verification tests were performed in order to verify the structural integrity during initial operation of the reactor coolant systems and the primary heat transportation systems of nuclear power plants by KEPRI in Korea. The tests were conducted at full operating temperature and pressure. The objective is to evaluate the possibility of excessive load generating on piping, piping supports, and reactor structures etc. in the steady normal operation and expected pump transient conditions. (omitted)

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Coprime factor reduction of plant in $H{\infty}$ mixed sensitivity problem

  • Um, Tae-Ho;Oh, Do-Chang;Park, Hong-Bea;Kim, Soo-Joong
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.340-343
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    • 1995
  • In this paper, we get a reduced order controller in $H^{\infty}$ mixed sensitivity problem with weighting functions. For this purpose, we define frequency weighted coprime factor of plant in $H^{\infty}$ mixed sensitivity problem and reduce the coprime factor using the frequency weighted balanced truncation technique. The we design the controller for plant with reduced order coprime factor using J-lossless coprime factorization technique. Using this approach, we can derive the robust stability condition and achieve good performance preservation in the closed loop system with reduced order controller. And it behaves well in both stable plant and unstable plant.t.

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Development of drive mechanism for 245kV 40kA high-voltage Gas Insulated Switchgear(GIS) using SPMSM (SPMSM을 이용한 '245kV 40kA GIS' 조작기 개발)

  • Jeong, Kyun-Ha;Seo, Kyong-Bo;Kim, Jung-Bea;Suh, In-Young
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.980-981
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    • 2008
  • Mechanical spring and hydraulic pressure operated mechanisms are applied in most of today's High Voltage Gas Insulated Switchgear(GIS)s. This paper proposes a new type of operation mechanism for GIS circuit breakers rated at 245kV and 40kA. The Motor-Direct-Drive-Mechanism (MDDM) has many advantages compared to conventional operating mechanisms. It has a very simple structure with only one moving part, low mechanical stress and audible noise. It also allows monitoring, operation speed control and self-diagnosis functions.

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Electrical Properties of $V_{1.9}W_{0.1}O_5$ Thin Films for the uncooled Infrared Detector (비냉각 적외선 감지소자 응용을 위한 $V_{1.9}W_{0.1}O_5$ 박막의 전기적 특성)

  • Nam, Sung-Pill;Lee, Sung-Gap;Bea, Seon-Gi;Lee, Young-Hie
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.1248-1249
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    • 2008
  • The $V_{1.8}W_{0.2}O_5$ thin films deposited on $Pt/Ti/SiO_2/Si$ substrates by RF sputtering method exhibited fairly good TCR and dielectric properties. It was found that film crystallinity, dielectric properties, and TCR properties were strongly dependent upon the annealing temperature. The dielectric constants of the $V_{1.8}W_{0.2}O_5$ thin films annealed at 400$^{\circ}C$ were 38.11, with a dielectric loss of 0.134, respectively. Also, the TCR values of the $V_{1.8}W_{0.2}O_5$ thin films annealed at 400$^{\circ}C$ were about -3.15%/K.

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Electromagnetic Field Analysis and Design of High Voltage Vacuum Interrupter (초고압 진공 인터럽터의 전자계 해석 및 설계)

  • Ryu, Jaeseop;Bea, ChaeYoon;Park, Seok Won;Kim, Young Geun
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.776-777
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    • 2015
  • 본 논문에서는 송전급 전력계통 적용을 위한 축자계 방식의 전극 구조를 갖는 진공 인터럽터의 전자계 해석 및 설계에 대해서 기술하였다. 상대적으로 극간 거리가 먼 초고압 진공인터럽터의 전극 구조로 축자계 방식을 채택하였으며, 효과적인 아크 확산 면적을 확보하기 위하여 자계 해석을 통해 전극 사이즈를 선정하였다. 또한, 접지된 금속외함 내에서 진공 인터럽터의 절연을 확보하기 위하여 전계 해석을 통해 전극 및 쉴드 등의 형상 설계를 수행하였다. 본 논문에서는 72.5kV 40kA 정격의 진공 인터럽터의 설계를 위한 전자계 해석 결과를 실험결과와 비교하여 설계 기준의 타당성을 검증하였고, 국제표준인 IEC 62271-100의 시험 규격에 의한 차단시험을 통하여 설계된 진공 인터럽터의 성능을 검증하였다.

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Analysis of Aging Characteristics in Oil Immerged Pole Transformer (과부하 및 경년 변압기 절연유 열화 특성 분석 연구)

  • Lee, Byung-Sung;Song, Il-Keun;Lee, Jae-Bong;Park, Dong-Bea;Han, Sang-Ok
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.05c
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    • pp.203-207
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    • 2002
  • In order to evaluate the aging of mineral oil immersed distribution transformers, it gathered some insulation oil in over loaded and long time(exceed their service life, 13yrs.) aged transformers in the field, we measured moisture content, acid number, dielectric strength of the oil as defined in KS C 2101 standard. And also, it had been measured dielectric constant, specific resistant, $tan{\delta}$ on aged transformer oil at from $10^{\circ}C$ to $130^{\circ}C$. These results are compared with a new mineral oil. From this study, it can be considered that the analysis of mineral oil may be suitable for evaluation of life expectancy in distribution transformers

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Using Protective Relaying for Power Quality Monitoring (보호계전기를 이용한 전기품질 감시 기법 연구)

  • Bea, Y.J.;Lim, S.I.;Choi, I.S.;Lee, S.J.;Kim, J.H.;Kim, B.J.
    • Proceedings of the KIEE Conference
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    • 2002.11b
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    • pp.62-64
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    • 2002
  • Power quality monitoring system is devoted to more concern than before, because the innovation of industrial technology needs more accurate instruments and more advanced power quality. Therefore, this paper is proposed to use digital protective relays for power quality monitoring. In addition, taking power quality events, Electrical magnetic phenomenon of IEEE std 1159, proposing that adaptive power quality event list consider limitation memory capacity and signal processing ability of protective relay. The prototype S/W of power quality analysis is also developed. Especially this prototype S/W analysis scheme is verified through many kinds of power quality events (gathering protective relay data) in EMTP simulation.

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M&A 아카데미 - M&A유형과 사례(2)

  • Sin, Gi-Hun
    • Venture DIGEST
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    • s.130
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    • pp.36-37
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    • 2009
  • 자바로 유명한 세계적 IT기업 썬마이크로시스템즈가 오라클과 합병한다는 소식이 세계 IT시장을 떠들썩하게 하고 있다. 썬은 이미 IBM과 상당히 발전된 M&A 논의를 진행시키다 오라클로 방향을 선회하는 깜짝쇼를 보여주었고, 이에 오라클은 첫 1년간 영업이익 15억 달러 증가를 예상하고 있다고 한다. 이미 피플소프트와 BEA 등 기업용 소프트웨어 및 서비스업체를 인수하며 성장해온 오라클은 서버기업인 썬을 인수하면서 SW/HW 모두를 망라하는 전방위 IT 기업으로 '단숨'에 성장하게 되었다. 그러나 이제부터다. 어떤 기업이든 M&A를 결정한 이후로 얼마나 전략적으로 과정을 진행하느냐에 따라 기업의 업그레이드를 이뤄낼 수 있다. 이번 호에서는 지난 호에 이어 주식스왑을 중심으로 M&A유형과 사례를 살펴보도록 하자. 아울러 또 다른 M&A의 유형인 주식의 포괄적교환과 꼭 알아두어야 할 몇 가지 항목을 살펴보도록 하자.

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A STUDY ON CONTINUOUS POSITIONING METHOD USING INTERLOCKING RFID AND GPS

  • Song, Woo-Seok;Lee, Jung-Ho;Bea, Hwan-Sung;Yu, Ki-Yun
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.564-567
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    • 2007
  • GPS(Global Positioning System) data has a high accuracy at outdoor positioning generally, but its accuracy decreases in the urban areas with dense buildings. Moreover insufficient number of satelllites prevent us GPS positioning at inside of buildings. To complement these shortcomings of GPS, RFID(Radio Frequency IDentification) has been studied on indoor positioning parts. In Ubiquitous environment, LBS(Location Based Service) which can be used anytime and anywhere is an essential component. We use kalman filter to estimate the real location in GPS and RFID handover area. This study's purpose is to make a continuous positioning system using interlocking RFID and GPS.

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