• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.438-441
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• 1997

This paper studies a semi-active suspension with ER damper controlled Fuzzy Net Controller designed GA(Genetic Algorithm). Apparent viscosity of ERF(Electro-Rheological Fluid) can be changed rapidly by applying electric field. Semi-active suspension for ground vehicles are expected to improve ride quality with less vibration. This paper deals with a two-degree -of-freedom suspension using the ER damper for a quarter vehicle system. In this paper, the GA is applied for generating Fuzzy Net Controllers. The GA designs the optimal structure and performance of Fuzzy Net Controller having hybrid structure. Computer simulation results show that the semi-active suspension with ER damper has good performances of ride quality.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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• pp.38-42
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• 2002

In the recent, electro-rheological fluid has been used for micro polishing of the 3-dimensional micro-aspherical lens and some sectional parts with defects on the wide flat wafer. The ER fluid has the properties that its viscosity has drastic changed under some electric fields. Therefore, ER fluid can be applicable to the micro polishing fur some parts using these properties. In this paper, the experimental device has been constructed using the precision milling machine in order to micro polishing far some sectional parts of a 4 inches wafer It is consisted of a small steel electrode, a wafer fixture, DC10mA and 5KV power supply unit, and a controller unit. Using the ER experimental device, possibility of amending for wide flat wafer and micro polishing of some micro part has been analyzed.

• 대한의생명과학회지
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• 제13권2호
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• pp.153-155
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• 2007

Ferritin heavy chain 1 (FTH1) is an ubiquitous and highly conserved protein which plays a major role in iron homeostasis. The expression of FTH1 was specifically enhanced under various condition of endoplasmic reticulum (ER) stresses drugs such as Brefeldin A (BFA), DTT (Dithiothreitol), calcium ionophore A23187 and tunicamycin. We firstly report here that ER-stress induces up-regulated expression of FTH1 in FRTL-5 culture thyrocytes.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.968-971
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• 2002

Two decisive mechanisms of the electrorhological polishing for a small part(for example, a aspherical surface in a micro lens) are explained. Firstly, non-uniform electric field generated in the polishing structure increases a shear stress of ER fluids which is maximized dramatically near the tool, therefore, substrate adjacent to the tool can be removed effectively by mixed abrasives in the ER fluid. Secondly, abrasives in a non-uniform electric field are governed by the dielectrophoretic phenomena. Abrasives move toward the tool because the field gradient is highest near the tool and then abrasives are actively holded in that area. This phenomena is observed and evaluated by the optical measurement.

• 한국정밀공학회지
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• 제23권1호
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• pp.105-112
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• 2006

The nonlinear damping force model is made to identify the properties of the ER (electro-rheological) fluid suspension damper. The instrumentation is carried out to measure the damping force of the ER damper. The higher order spectral analysis method is used to investigate the nonlinear frequency coupling phenomena with the damping force signal according to the sinusoidal excitation of the damper. The distinctive higher order nonlinear characteristics are observed. The nonlinear damping force model, which has the higher order velocity terms, is proposed with the result of higher order spectrum analysis. The higher order terms coefficients, which vary according to the strength of the electric field, are calculated using the least square method.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2000년도 춘계학술발표논문집
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• pp.30-35
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• 2000

초고속통신의 실현과 다양한 멀티미디어정보의 QoS를 향상시키기 위한 ATM 방식은 TCP/IP 통신의 기본적인 전송 매카니즘으로 사용되고 있다. TCP가 ATM 망에서의 ABR서비스를 사용할 때 ABR의 율 기반 제어와 TCP 흐름제어사이에 상호작용이 없는 한, 이런 환경하에서 ATM망의 ABR 트래픽을 좀더 효율적으로 제어하기위해서는 EFCI-ER 스위치 방식의 상호혼용 운영이 불가피하다. 본 논문에서는 이러한 상호혼용을 위하여 EFCI-ER 스위치의 혼용망을 모델로 하여 여러 가지 ER 스위치 알고리즘을 이용하여 대역할당의 공정성 셀손실을 그리고 처리율을 구하였다. 시뮬레이션 결과로써 여러 가지 ER 스위치 알고리즘중에서 망의 형태에 영향을 덜 받으면서 VC(Virtual Channel) 에 공정하게 대역폭을 할당할 수 있는 하나의 알고리즘을 나타내었다.

• Transactions on Electrical and Electronic Materials
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• 제15권6호
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• pp.348-352
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• 2014

In light of the sure protection function, the most important factors of a varistor are the clamping voltage ratio and degradation characteristics. The degradation characteristics of Pr/Co/Cr/Er co-doped zinc oxide varistors were investigated by impulse currents (0.4~2.1 kA) stress for the specified content of $Er_2O_3$ (0.5 and 2.0 mol%). The varistor doped with 2.0 mol% $Er_2O_3$ exhibited the best clamp characteristics, with the clamp voltage ratio (K) in the range of K = 1.63~1.88 at the impulse currents of 5-50 A. However, the varistor doped with 0.5 mol% exhibited excellent electrical stability, with variation rates for the breakdown field, for the nonlinear coefficient, and for the leakage current density of -6.9%, -12.6%, and -14.3%, respectively, after application of an impulse current of 2.1 kA. In contrast, the varistor doped with 2.0 mol% was destroyed after application of an impulse current of 1.2 kA.

• 한국공작기계학회논문집
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• 제14권3호
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• pp.32-37
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• 2005

Several types of smart materials and control scheme are available to adjust the structure actively in various external disturbances. A control scheme was introduced for a specific material. But the effectiveness of the control scheme has some limitation according to the choice of the smart materials and the response of the structure. The ER(Electrorheological) fluid is adequate for a large control force, and the PZT(lead zirconate titanate) patches are suitable for small but arbitrary control force at any point of the structure. It can be used for active control of structure by changing the dynamic characteristics of the structure. But it has some difficulty in suppressing the excited vibration in broad band. To compensate this resonance of the controlled structure, a hybrid controller was constructed using PPF(Positive position feedback) control with PZT and ER fluid control.

• 한국수정란이식학회지
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• 제5권2호
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• pp.28-37
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• 1990

Dihydrotestoterone (DHT)은 난소내 폐쇄를 유발한다고 보고 되었으나, 반대로 폐쇄를 억제한다는 상반된 주장이 있어왔다. 본 연구는 난소내 폐쇄되는 기작을 밝히는 연구의 일환으로 흰쥐의 DHT를 처리하여 난포가 폐쇄되는지 여부와 폐쇄된다면 스테로이드 수용체, 특히 에스트라디올 수용체에 어떠한 영향을 주는지를 조사하고자 하였다. 미성숙 흰쥐의 뇌하수체를 절제(HPX)하고, 35IU의 PMSG 처리후 Dihydrotestoterone enathate (DHTE)를 lmg-5mg/kg 체중 농도로 처리하여 난포의 폐쇄여부를 조직학적으로 검경하였다. PMSG,PMSG-DHTE 공히 강소를 형성한 난포의 acid phosphatase 활성도를 증가시켰고, 또한 난포의 폐쇄를 유발하였다. 흰쥐의 난소내 estrogen receptor (ER)의 수는 과립세포에서도 세포질내 ER은 핵내로 이용되는 것을 확인하였다. 또한 DHTE는 난소내 ER의 농도를 감소시켰다. 이 결과로 보아 난포내 DHTE는 ER의 농도를 감소시켜 폐쇄를 유발하는 요인으로 작용할 것이라는 결론을 얻었다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 추계종합학술대회
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• pp.288-291
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• 2000

ATM 망에서는 전송률 기반의 ABR 흐름제어를 위해 다수의 알고리즘들이 제안되고 있다. 이 알고리즘들의 주 목적은 셀 손실률을 회피하고 미사용중인 대역폭을 ABR 트래픽에 의해 사용되게 하는 것이다. 이러한 알고리즘들은 EFCI와 ER 스위치에서 동작하여 ABR 트래픽을 재어하는데 사용된다. 이전 논문에서 이러한 스위치 알고리즘들을 network에 적용하여 각 알고리즘들의 성능에 의한 대역 이용률을 도시하였다. 본 논문에서는 이의 보완을 위해 각 알고리즘들의 셀 손실률과 회선 이용률을 도시하여 그 성능을 비교, 분석하고자 한다.