• Journal of electromagnetic engineering and science
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• 제6권3호
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• pp.155-159
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• 2006

An efficient method is presented to design filters without the similarity transform of their coupling coefficient matrix as circuit parameters, which is very tedious due to pivoting and deciding rotation angles needed during the iterations. The transfer function of a filter is directly used for the design and its desired form is derived by the optimized rational-function fitting technique. A 3rd order coaxial lowpass filter is taken as an example to validate the proposed method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.1092-1095
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• 1996

In this paper The tuning of PID controller for multi input-output is studied by using fuzzy inference. State of coupling is estimated by fuzzy inference, its results is used for tuning of PID controller to get optimum P,I,D parameter with regard to state of coupling. This method is simulated to Turbo-generating system with $2{\times}2$ multi input-output and made with electronic circuit, its response is very satisfactory.

• 대한전자공학회논문지
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• 제26권2호
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• pp.56-65
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• 1989

본 논문에서는 결합된 구형 마이크로스트립 안테나사이의 간격에 대한 새로운 등가모델인 Radiating Edges-Coupling(REC) 모델을 제시하였다. REC모델은 균일한 유전체로 채워져 있고 윗면에 슬릿이 있는 평행평판 도파로의 등가회로로 부터 유도하였다. 결합간격이 0.5, 1.0, 1.5, 및 2.0mm인 경우에 REC모델을 적용하여 2.5GHz와 3.5GHz 사이의 주파수에서 산란계수 | $S_{11}$ |과 |$S_{12}$|의 이론치와 실험치를 비교한 결과 서로 일치되는 양호한 특성을 얻었다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2014년도 전력전자학술대회 논문집
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• pp.335-336
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• 2014

This paper investigates the design of coupled inductor for minimum inductor current ripple in rapid traction battery charger systems. Based on the general circuit model of coupled inductor together with the operating principles of dc-dc converter, the relationship between the ripple size of inductor current and the coupling factor is derived under the different duty ratio. The optimal coupling factor which corresponds to a minimum inductor ripple current becomes -1, i.e. a complete inverse coupling without leakage inductance, as the steady-state duty ratio operating point approaches 0.5. In an opposite manner, the optimal coupling factor value of zero, i.e. zero mutual inductance, is required when the steady-state duty ratio operating point approaches either zero or one. Coupled inductors having optimal coupling factor can minimize the ripple current of inductor and battery current resulting in a reliable and efficient operation of battery chargers.

• Nuclear Engineering and Technology
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• 제51권7호
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• pp.1842-1852
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• 2019

The AP1000 reactor coolant pump is a vertical shielded-mixed flow pump, is the most important coolant power supply and energy exchange equipment in nuclear reactor primary circuit system, whose steadystate and transient performance affect the safety of the whole nuclear island. Moreover, safety demonstration of reactor coolant pump is the most important step to judge whether it can be practiced, among which software simulation is the first step of theoretical verification. This paper mainly introduces the fluid-solid coupling simulation method applied to reactor coolant pump, studying the feasibility of simulation results based on workbench fluid-solid coupling technology. The study found that: for the unsteady calculations of the pure liquid media, the average head of the reactor coolant pump with bidirectional fluid-solid coupling decreases to a certain extent. And the coupling result is closer to the real experimental value. The large stress and deformation of rotor under different flow conditions are mainly distributed on impeller and idler, and the stress concentration mainly occurs at the junction of front cover plate and blade outlet. Among the factors that affect the dynamic stress change of rotor, the pressure load takes a dominant position.

• 전력전자학회논문지
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• 제23권4호
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• pp.247-255
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• 2018

This paper proposes a transformer design of a direct cell-to-cell active cell balancing circuit with a multi-winding transformer for battery management system (BMS) applications. The coupling coefficient of the multi-winding transformer and the output capacitance of MOSFETs significantly affect the balancing current transfer efficiency of the cell balancing operation. During the operation, the multi-winding transformer stores the energy charged in a specific source cell and subsequently transfers this energy to the target cell. However, the leakage inductance of the multi-winding transformer and the output capacitance of the MOSFET induce an abnormal energy transfer to the non-target cells, thereby degrading the transfer efficiency of the balancing current in each cell balancing operation. The impacts of the balancing current transfer efficiency deterioration are analyzed and a transformer design methodology that considers the coupling coefficient is proposed to enhance the transfer efficiency of the balancing current. The efficiency improvements resulting from the selection of an appropriate coupling coefficient are verified by conducting a simulation and experiment with a 1 W prototype cell balancing circuit.

• 한국광학회지
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• 제16권3호
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• pp.266-274
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• 2005

본 논문에서는 2차원 광결정 공진기의 결합을 통해 WDM시스템에 적합한 특성을 가지는 공진 필터를 설계하였다. 공진기간의 결합에 있어서 고려해야 할 요소를 시영역에서의 모드 결합이론(coupling modes in time)을 적용하여 이론적으로 분석하였으며, 전자회로 등가화를 이용하여 쉽게 그 요소를 결정할 수 있음을 보였다. 공진기 결합에 있어서 공진기 간의 간격에 따른 위상천이에 대해서 외부감쇄에 의한 Q-factor를 조정함으로써 보상할 수 있음을 확인하였고, 2차원 광결정 점결함 공진기를 이용하여 500GHz의 대역폭을 가지며 통과대역에서 0.5 dB 리플을 가지는 3차 Chebyshev 대역 통과 필터를 설계하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.395-398
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• 2004

We developed an a-Si TFT-LCD panel with integrated gate driver circuit using a standard 5-MASK process. To minimize the effect of the a-Si TFT current and LC's capacitance variation with temperature, we developed a new a-Si TFT circuit structure and minimized coupling capacitance by changing vertical architecture above gate driver circuit. Integration of gate driver circuit on glass substrate enables single chip and 3-side free panel structure in a-Si TFT-LCD of QVGA(240$^{\ast}$320) resolution. And using double ASG structure the dead space of TFT-LCD panel could be further decreased.

• 전기전자학회논문지
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• 제21권2호
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• pp.150-153
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• 2017

본 논문에서는 Floating기술을 이용한 GCNMOS 기반의 ESD(Electrostatic Discharge)보호회로를 제안한다. 제안된 보호회로의 특성 분석을 위해서 시놉시스사의 TCAD 시뮬레이션을 이용하였으며 기존의 GGNMOS, GCNMOS와 비교 분석하였다. 제안된 보호회로는 Gate coupling과 Body floating기술을 적용하였으며 기존 ESD보호회로인 GGNMOS, GCNMOS와 비교하여 더 낮은 4.86V의 트리거 전압 및 1.47ns의 짧은 턴-온 타임 특성을 갖는다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.1139-1140
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• 2008

This paper is designated to introduce the method of reducing stand-by Power of SMPS applied PLC(Power Line Communication) and its implementation. PLC modem consists mainly of PLC Module, Coupling Circuit, ZCP(Zero-Cross Point) Circuit and Power Supply Circuit. By controlling power from Power Supply Circuit to PLC Module and ZCP Circuit, the reduction of Stand-by Power is established. When this method is applied to SMPS used for a low-speed PLC, about 50% power reduction is provided, compared to the other case to which it is not applied.