• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.41-45
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• 1996

비접촉방법데 의한 변위 측정기술은 공작물의 가공중(in-process)형상치수의 측정 또는 각종 계 측에 대한 자동화기술의 필요성이 증대됨에 따라 다양한 원리를 응용하여 발전되고 있다. 전통적인 방법으로는 가변 리럭턴스(variable reluctance)형, 와전류(eddy current)형, 콘덴서(capacitance)형 등의 전기적 센서들이 주를 이루고 있으나 최근에 들어서는 광전자기술의 발달에 힘입어 여러 광학 측정법들이 연구되어 실용화 되고 있다. 본 연구에서는 측정자동화 용도로 사용될 수있는 광삼각법에 의한 비접촉방식의 광학센서에 대한 기본 연구 결과를 서술하였다. 광삼각 비접촉 측정의 기본 원리와 측정 범위 및 분해능 관점에서의 센서 설계의 기본 방법을 제시하며 또한, 실제적인 센서의 설계 및 제작을 위해 응용될 수 있는 기본광학소자의 현 기술적 수준과 성능을 기술하였다. 최종적으로는 실제적인 센서의 설계제작 과정과 시제품의 성능 실험을 통한 응용 가능성이 검토되었다.

• Journal of Power System Engineering
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• v.10 no.2
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• pp.41-46
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• 2006

This study shows a water cooling system by using a steam ejector and jet condenser to drop the temperature of the water by about $5^{\circ}C\;from\;25^{\circ}C$ or higher. In this research, to replace the present water cooling system, we focused on a water cooling system by latent heat of evaporation, thus this system needs a vacuum pressure to evaporate the water in enclosed tank. The water cooling effects are depended on the vacuum pressure in the enclosed tank, and the cooling water is generated by latent head of evaporation. As the experimental results, the absolute vacuum pressure obtained was about $5{\sim}8$ mmHg using a steam driven ejector with jet condenser.

• Journal of the Microelectronics and Packaging Society
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• v.1 no.2
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• pp.113-124
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• 1994

MOD법을 마이크로회로용 티탄산 바륨 콘덴서 박막형성에 적용하였다. Barium decanoate barium 2-ethylhexanoate titanium dimethoxy didecanoate 및 titanium dimethoxy di-2-ethylhexanoate와 같은 여러 가지 금속유기화합물들을 합성하고 동정한 다 음 공통용매에 대한 용해도를 시험하였다. 이금속유기화학물들 가운데 barium 2-ethylhexanoate와 titanium dimethoxy di-2-ethylhexanoate가 xylene-pyridine 혼합용매에 잘녹고 MOD법에 의한 BaTiO3 박막형성에 매우 안정한 조성을 이룸을 확인하였다. 이 조 성을 스핀코팅에 의하여 백금박과 실리콘 웨이퍼상에 금속유기화학물 막을 형성하고 최고 온도와 유지시간에 따라 소성하여 형성된 유전체 박막들의 전기전 특성을 측정하고 고찰하 였다.

• Journal of Aerospace System Engineering
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• v.2 no.3
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• pp.40-44
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• 2008

T-50 ECS(environment control system) was designed to have freezing protection for the condenser. However during the ground and flight test, the freezing problem was occurred. This paper deals with the analysis of the freezing problem and introduces anti-freezing design using ADI(Active De-Icing) logic to solve the condenser freezing problem of T-50 ECS

• Journal of Sensor Science and Technology
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• v.16 no.3
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• pp.174-178
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• 2007

This paper presents a novel, highly sensitive condenser microphone with a flexure hinge diaphragm. We used the finite-element analysis (FEA) to evaluate the mechanical and acoustic performance of the condenser microphone with a hinge diaphragm. And we fabricated the miniature condenser microphones with area of 1.5 mm${\times}$1.5 mm. From the simulation results, we confirmed that the maximum displacements at the center of flexure hinge diaphragms are several hundred times, compared with flat diaphragms. The sensitivities of fabricated miniature microphones are about $12.87{\mu}V/Pa$ at 1 kHz under a low bias voltage of 1 V, and the frequency response is flat upto 13 kHz.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.6-8
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• 1995

This paper describes the characteristic- analysis and tile optimum design of the single-phase permanent-split condenser motor. The equivalent circuit is constructed by the symmetrical coordinate method and proved its validity by comparing with the experimental data. Then, the numerical optimization technique is applied to improve the efficiency of the motor.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.619-620
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• 2008

Reactor starting method has the advantage of simplicity and closed transition in spite of lower starting torque per kVA. This method allows a smooth start with almost no observable disturbance on transition and is suitable for applications such as centrifugal pumps or fans. Starting power factor is specially low. Power factor application is needed to compensate for the lower power factor of induction motor. This power factor compensation systems is being hit by the effects of the starting reactor connection position. This paper describes voltage and current stress affected by the installation position of power factor compensation application at the reactor starting method.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.928-929
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• 2008

A dc/dc power conversion system using multi stage capacitor is proposed in this paper. The proposed new type converter is designed from high efficiency dc/dc converter with fixed boost ratio and variable voltage converter. The tests have been done using PSIM computer simulation to confirm the analysis and control concept.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.05a
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• pp.78-81
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• 2008

Capacitors are known as condensers. They play an important in the industrial site because of benefits such as var support, improved voltage control and power factor, increased system capacity, and reduction of system power losses. But capacitors can be seriously affected by bad power quality such as transient and impulsive overvoltage, overload, harmonics. Capacitor standards and application guides are revised or supplemented by speedy technology advancements in the manufacturing of capacitors and in the power electronics. This paper presents various illustrations and comparison for several standards of power system capacitors.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.424-427
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• 2006

본 논문에서는 DVR 시스템 구성을 위한 환경친화적 EDLC(전기이중층콘덴서)의 특성해석에 관한 연구를 수행하였다. 순시적인 전압 새그 발생시 급속 충 방전 및 에너지 밀도를 고려한다면 기존 전해캐패시터 보다는 EDLC의 채용이 적당하다. EDLC를 채용한 DVR시스템에서 EDLC의 등가직렬저항 및 정전용량 등은 DVR 인버터의 부하 용량 결정에 따른 보상시간을 결정하므로 이의 내부 특성을 해석할 수 있어야만 한다. 따라서 본 연구에서는 EDLC의 내부 파라미터 추출기법 및 구동부의 DC/DC 컨버터에 관한 해석을 수행하고 EDLC를 채용한 DVR의 구성에 따른 실험결과를 제시한다.