• 한국신재생에너지학회:학술대회논문집
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• 2005.11a
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• pp.165-172
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• 2005

본 고에서는 태양전지 모듈 원가의 60% 이상을 차지하는 실리콘 기판의 생산성을 향상시키고 그에 따라 제조단가를 저감시키기 위한 일환으로 최근 들어 일본과 프랑스를 중심으로 중점적으로 기술개발이 이루어지고 있는 EMCC법(Electro Magnetic Continuous Casting)에 의한 다결정 실리콘 잉고트의 제조기술에 관하여 연구하였다. 특히, 태양전지급의 고순도 잉고트로 제조하기 위해 높은 용융점과 낮은 전기전도도를 갖는 실리콘의 용해 및 주조 공정이 수냉되는 cold crucible 내에서 이루어지게 됨에 따라 발생하는 종래의 EMCC법의 문제점을 해결하고자, 코일전류 및 도가니 구조 등이 Joule 가열 효과 및 pinch 효과에 미치는 영향을 체계적으로 조사하였다. 연구 결과 대용량의 전원장치나 별도의 2차 가열원을 사용하지 않고서도 실리콘 원료의 가열 및 용해 효율을 현격히 향상시키며 용탕의 전 구간에 걸쳐 전자기력을 용탕의 정수압보다 큰 상태로 유지할 수 있는 EMCC용 무접촉성 도가니의 설계기술 및 이를 활용하는 전자기연주공정기술을 확립하였으며, 그 결과 직경 5 cm의 실리콘 잉고트를 1.5 mm/min의 속도로 무접촉 조건에서 연속주조할 수 있었다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.373-378
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• 2004

Recently the electrostatic 2-axis MEMS stages have been fabricated for the purpose of an application to PSD (Probebased Storage Device). However, most of them have low area efficiency, which is undesirable as data storage devices, since all of the components (springs, comb electrodes, anchors, platform, etc.) are placed in-plane. In this paper, we present a novel structure of electrostatic 2-axis MEMS stage that is characterized by having large area platform. For large area efficiency, the actuator part consisting of mainly comb electrodes and springs is placed right below the platform. In this article, the structures and operational principle of the MEMS stages are described, followed by design procedure, structural and modal analysis using FEM(Finite Element Method). The area efficiency of the MEMS stage was designed to be about 55％, that is very large compared with conventional ones having a few percentage.

• Proceedings of the KIEE Conference
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• 2003.11b
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• pp.235-238
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• 2003

In this study, we propose a method of digital control to drive the vibrating gyroscope using electromagnetic-force. The gyroscope requires accurate vibration control and signal processing for high performance. Conventional PLL based analog controller is not only difficult to manufacture but also weak to outer environment such as temperatures, air pressures and etc. But digital controller using DSP can consistently maintain the cylinder vibration and perform digital signal processing regardless of disturbance. DSP's PWM function was utilized to control the vibration, and rotation-detecting algorithm was developed. Finally, the controller was verified by simulation and experiment using rotation-rate table.

• Proceedings of the KIPE Conference
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• 2017.11a
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• pp.79-80
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• 2017

변압기 기계적 손상의 주요 원인은 단락전류에 의해 발생하는 전자기력이다. 상용 변압기는 특정 수준의 기계적 강도를 견디게 설계 되어야 하며 단락전류에 의한 변압기 특성 변화를 검증하기 위한 단락성능시험은 국제 표준에 따라 시행되어야 한다. ITER CS 3상 정류기 변압기의 단락시험은 IEC 표준에 따라 전기연구원에서 시행되었으며 그 결과를 본 논문에서 소개하고자 한다.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.290-292
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• 2003

탐침형 고밀도 정보저장장치의 구현에 필수적인 초정밀 구동기의 성능을 개선하기 위해 단순화된 모형을 설정하고 각 설계 변수들이 구동 특성에 미치는 영향을 분석하여 이를 통해 원하는 사양의 구동기를 설계하고 실제 제작을 통해 그 모형의 타당성을 검증하였다. 전자기력을 이용한 구동기는 변위, 공진 주파수 등 여러 조건을 동시에 만족시켜야하나 전자기-기계가 복합적으로 결합된 시스템이므로 그 특성의 이해와 설계를 위해서는 보다 단순화된 모형의 도입이 필요하다. 본 논문에서는 코일부를 단순화하고 자석으로부터 인가되는 평균자기장을 통해 구동 특성을 분석하였으며 이는 실제 제작 결과와 잘 일치하였다.

• Proceedings of the KIEE Conference
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• 2007.04c
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• pp.141-143
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• 2007

This paper presents the MHD characteristics of the liquid metal flow. The electromagnetic force was calculated by the equivalent circuit method. This Lorentz force was used as a source term for the fluid flow equations. The modified Navier-Stokes equation was solved to give the velocity distributions of the liquid metal flow.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.3
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• pp.158-164
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• 2000

In recent year, desire and request fer micro automation are growing rapidly covering the whole range of the industry. This has been caused mainly by request of more accurate manufacturing process due to a higher density of integrated circuits in semiconductor industry. This paper presents a six d.o.f fine motion stage using magnetic levitation technique, which is one of actuating techniques that have the potential for achieving such a micro motion. There is no limit in motion resolution theoretically that the magnetically levitated part over a fixed stator can realize. In addition, it Is possible to manipulate the position and the force of the moving part at the same time. Then, the magnetic levitation technique is chosen into the actuating method. However, we discuss issues of design, kinematics, dynamics, and control of the proposed system. And a few experimental results fur step input are given.

• Proceedings of the KIEE Conference
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• 2008.10a
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• pp.181-182
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• 2008

In this paper, we present the design of an electromagnetic scanning mirror with rotated serpentine springs. We considered three types of torsional springs: simple beam springs (SBS), classic serpentine springs (CSS), and rotated serpentine springs (RSS). The analysis was done for an electrical resistance, differences in the mode-frequency, and resonances regarding to spring thickness. Electromagnetic coils under the mirror plate were also analyzed for power consumption and the mechanical deflection. From the analysis result, RSS and electromagnetic coils were designed for the silicon scanning mirror.

• Journal of Korean Medical classics
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• v.18 no.1 s.28
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• pp.57-66
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• 2005

통과대(通過對)${\ulcorner}$황제내경(黃帝內經)${\lrcorner}$ 중제출적여불면상관적17편경문적고찰(中提出的與不眠相關的17篇經文的考察), 진행불면원인적연구(進行不眠原因的硏究), 득출여하결논(得出如何結論): 수면화불면(睡眠和不眠), 여인체내위기적활동유관(與人體內衛氣的活動有關). 즉백주위기행어양분(卽白晝衛氣行於陽分), 고능소성(故能蘇醒); 이야만위기행어음분(而夜晩衛氣行於陰分), 칙능입수(則能入睡). 위기능구순리지출입내외, 기력양시유오장적정기제공적(其力量是由五臟的精氣提供的). 인차개괄이언(因此槪括而言), 불면적원인시음허양왕적상태(不眠的原因是陰虛陽旺的狀態). 수연불면불과시일종병증(雖然不眠不過是一種病症), 단기원인시다양적(但其原因是多樣的). 재경문중소견적원인(在經文中所見的原因), 진행개괄여하(進行槪括如下): 양기원성(陽氣元盛), 양명경실조(陽明經失調), 위중불화(胃中不和), 오장수손상(五臟受損傷), 혹인년노오장정기불족(或因年老五臟精氣不足), 인광증혹혼백비양이(因狂症或魂魄飛揚而) 치적다몽등심리장애(致的多夢等心理障碍), 비생리성수사체류(非生理性水邪滯留), 인침자오치이치적음정손상혹수사조장(因針刺誤治而致的陰精損傷或水邪助長).

• Journal of Korea Foundry Society
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• v.21 no.6
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• pp.328-335
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• 2001

The objective of this study is to investigate on manufacturing Al-scrap into hypereutectic Al-Si alloy by using electromagnetic force. The Fe element in the aluminium scrap was controlled by intermetallic compound method and using EMF(electromagnetic force). The most lumped compound was found after 10min holding at $690^{\circ}C$. A number of segregated compound was revealed when imposed to EMF at 30A. The refinement of primary Si particles was achieved by EMF stirring. Primary Si particles were refined and spheroidized most of all with the magnetic intensity of 180G for 10 min.