• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.189-192
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• 2001

Recently, STI process is getting attention as a necessary technology for making high density of semiconductor by devices isolation method. However, it does have various problems caused by CMP process, such as torn oxide defects, nitride residues on oxide, damages of si active region, contaminations due to post-CMP cleaning, difficulty of accurate end point detection in CMP process, etc. In this work, the various defects induced by CMP process was introduced and the above mentioned Problems of CMP process was examined in detail. Finally, the guideline of future CMP process was presented to reduce the effects of these defects.

• International Journal of Aeronautical and Space Sciences
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• 제18권3호
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• pp.579-587
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• 2017

Spaceborne cryocoolers produce undesirable micro-vibration disturbances during their on-orbit operation, which are a primary source of image-quality degradation for high-resolution observation satellites. Therefore, to comply with the strict mission requirement of high-quality image acquisition, micro-vibration disturbances induced by cooler operation have always been subjected to an isolation objective. However, in this study, we focused on the applicability of energy harvesting technology to generate electrical energy from micro-vibration energy of the cooler and investigated the feasibility of utilizing harvested energy as a power source to operate low-power-consumption devices such as micro-electromechanical system (MEMS) devices. A tuned mass damper (TMD)-type electromagnetic energy harvester combined with a conventional passive vibration isolator was proposed to achieve this objective. The system performs the dual functions of electrical energy generation and micro-vibration isolation. The effectiveness of the strategy was evaluated through numerical simulations.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.162-164
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• 2004

Nanocrystalline silicon(nc-Si) thin films on the silicon substrates have been prepared by pulsed laser deposition(PLD). The optical and structural properties of films have been investigated depending on deposition temperature, annealing, and oxidation process. When the deposition temperature increased, photoluminescence(PL) intensity abruptly decreased and peaks showed red shift. Annealing process could reduce the number of defect centers. Oxidation had a considerable effect upon the formation and isolation of the nanocrystals. These results indicate that the formation mechanism of Si nanocrystals grown by PLD can be explained by three steps of growth, passivating defect centers, and isolation, sequentially.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.776-777
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• 2011

조속기는 수차발전기의 핵심을 담당하는 두뇌라고 말할 수 있으며, 전력계통의 부하(주파수)가 변할 경우 수차발전기의 회전속도를 정격으로 유지시켜 양질의 전기를 생산하도록 항시 조정되는 역할을 한다. 최근 조속기는 디지털화되어 최적제어 감시 및 보호기능을 수행하고 있으나 문제점도 하나둘씩 나타나고 있는 실정이다. 본 논문에서는 디지털 가버너의 Isolation Mode에 대한 설명과 사고사례를 통해 디지털가버너 운영 시 문제점을 분석, 검토하여 보완하고자 하였으며, 이를 통해 안정적으로 전력공급을 주요 목적으로 하였다.

• ETRI Journal
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• 제35권4호
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• pp.718-721
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• 2013

This letter proposes a novel calibration method for a multiport amplifier (MPA) to achieve optimum port-to-port isolation by correcting both the amplitude and phase of the calibration signals. The proposed architecture allows for the detection of the phase error and amplitude error in each RF signal path simultaneously and can enhance the calibrated resolution by controlling the analog phase shifters and attenuators. The designed $2{\times}2$ and $4{\times}4$ MPAs show isolation characteristics of 30 dB and 27 dB over a frequency range of 19.5 GHz to 22.5 GHz, respectively.

• 제어로봇시스템학회논문지
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• 제3권3호
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• pp.244-251
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• 1997

In this paper, we propose a fault diagnosis algorithm to detect and isolate multiple faults in a system. The proposed fault diagnosis algorithm is based on a multiple fault classifier which consists of two ART2 NN(adaptive resonance theory2 neural network) modules and the algorithm is composed of three main parts - parameter estimation, fault detection and isolation. When a change in the system occurs, estimated parameters go through a transition zone in which residuals between the system output and the estimated output cross the threshold, and in this zone, estimated parameters are transferred to the multiple faults classifier for fault isolation. From the computer simulation results, it is verified that when the proposed diagnosis algorithm is performed successfully, it detects and isolates faults in the position control system of a DC motor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1724-1725
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• 2007

This paper presents a fault detection and isolation(FDI) scheme for a nonlinear systems with a actuator and sensor faults. A residual generator based on the observer model generate the information for a fault detection. The proposed fault estimators are activated for a fault isolation and applied to estimate the time-varying lumped faults(model uncertainty + fault). but a fault estimator error dose not converge to zero since the derivative of lumped fault is not zero. Then the fuzzy neural network(FNN) is used to estimate the fault estimator error. Simulation results are presented to illustrate the effectiveness and the applicability of the approaches proposed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1349-1351
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• 2005

In this paper discusses isolation driver of single phase AC-DC reversible power converter The reversible power converter driven by binary combination at different transformer winding ratio by BCD code level. It has a advantage that constructs a control system simply and obtain load current of good quality with out filter circuit and free from noise or isolation for lower switching frequency. In this research, study on current type converter and inverter circuit that consist for possibility of AC-DC/BC-AC multi-level reversible converter.

• 대한전자공학회논문지
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• 제23권6호
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• pp.801-806
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• 1986

The effect of SiH2Cl2 -HCl gas on the growth rate of epitaxial layer is studied. The temperature, pressure and gas mixing ratio of SiH2Cl2 and HCl are varied to study the growth rate dependence and selective Si epitaxy. The P-n junction diode is fabricated on the epitaxial layer and electrical characteristics are examined. Also, using selective Si epitaxy, a possibility of thin dielectric isolation process, that gives an independent isolation width on the mask dimension, is examined.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제36회 동계학술대회 초록집
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• pp.77-77
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• 2009