• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.531-534
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• 2003

The electro-optical characteristics of the In-Plane switching Twisted nematic (IT) mode were studied. The advantage of this mode is not only the wide viewing angle characteristics without adopting any compensation films, but also the wide cell gap error margin. The electro-optical characteristics of IT mode were evaluated by the experiments and computer simulation. In this paper, we studied the viewing angle characteristics, color-shift and response time.

• ETRI Journal
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• 제31권2호
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• pp.201-208
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• 2009

This paper proposes a spiral-shaped power island structure that can effectively suppress simultaneous switching noise (SSN) when the power plane drives high-speed integrated circuits in a small area. In addition, a new technique is presented which greatly improves the resonance peaks in a stopband by utilizing ${\lambda}$/4 open stubs on a conventional periodic electromagnetic bandgap (EBG) power plane. Both proposed structures are simulated numerically and experimentally verified using commercially available 3D electromagnetic field simulation software. The results demonstrate that they achieve better SSN suppression performance than conventional periodic EBG structures.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1994년도 봄 학술발표회 논문집
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• pp.95-102
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• 1994

A path-switching strategy by combining the use of generalized inverse and line search is proposed. A reliable predictor for the tangent vector to bifurcation path is first computed by using the generalized inverse approach. A line search in the direction of maximum gradient of total potential at the point of intersection between the above predictor and a constant loading plane introduced in the vicinity of the detected bifurcation point is then carried out for the purpose of obtaining an improved approximation for a point on bifurcation path. With this approximation obtained, an actual point on bifurcation path is then computed through iteration on the constant loading plane.

• Journal of electromagnetic engineering and science
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• 제6권1호
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• pp.62-70
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• 2006

This paper presents a new power plane design method incorporating a single geometry derived from a unit cell of photonic bandgap(PBG) structure. This method yields constantly wide suppression of parallel plate resonances from 0.9 GHz to 4.2 GHz and is very efficient to eliminate PCB resonances in a specified frequency region to provide effective suppression of simultaneous switching noise(SSN). It is shown that with only two cells the propagation of unwanted high frequency signals is effectively suppressed, while it could provide continuous return signal path. The measured results agree very well with theoretically predicted ones, and confirm that proposed method is effective for reducing EMI, with measured near-field distribution. The proposed topology is suitable for design of high speed digital system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.453-454
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• 2006

We studied the nematic liquid crystal (NLC) alignment capability by the IB(Ion bean) alignment method on a NDLC(Nitrogen Diamond Like Carbon) as a-C:H thin film. and investigated electro-optical performances of the IBaligned IPS(In plane switching)cell with NDLC surface. A good LC alignment by IB exposure on a NDLC surface was achieved. Monodomain alignment of the IB aligned IPS cell can be observed. The goodelectro-optical (EO) characteristics of the IB aligned IPS cell was observed with oblique IBexposure on the NDLC as a-C:H thin film for 1 min.

• 전자공학회논문지S
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• 제34S권8호
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• pp.45-55
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• 1997

To design a ATM Switch which ahs advantages in high sped packet switching, it is essential to set multiple paths between input ports and output ports and to design a new packet transfer technique on that paths for decreasing Packet Loss by conflicts in internal Switch Plane. We propose new packet transfer method, Alternate Path Transfer Mechanism by Dynamic Bypass Transfer Method which can solve conflict problem in Banyan network easily. Proposed ATM Switch consists of Banyan networks, Input/Ouput Port, Bypass Link, and Bypass Link Controller. Packets caused conflicts in SEs have another chances of packet transfer over alternate switching planes by using this mechanism.

• 드라이브 ㆍ 컨트롤
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• 제18권4호
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• pp.52-58
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• 2021

The variable structure controller is designed such that in sliding mode, the system moves along the switching plane in the vicinity of the switching plane, thus it is robust because it is not affected by the parameter fluctuations of the plant. However, a controller based on a variable structure may not meet the desired performance when it is commanded to track any input or is exposed to disturbances. This study proposes a sliding mode controller that follows the IVSC (Integral Variable Structure Control) approach with ELO (Extended Luenberger observer) to solve this problem. The proposed sliding mode control is applied to the velocity control of the hydraulic motor. The sliding plane was determined by the pole placement, and the control input was designed to ensure the existence of the sliding mode. The feasibility of modeling and controller are reviewed by comparing with conventional proportional-integral control through computer simulation using MATLAB software and experimenting on the cases of significant plant parameter fluctuations and disturbances.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.399-402
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• 1988

In this paper, the relationship between stability and gain band-width product (GB) is clear ed by evaluating the feedback gain in the buck-boost switching regulator. Especially, considering the effect of the right-half-plane pole on the stability, we found available region of GB on the stability with the one pole compensation for the feedback circuit.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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• pp.337-341
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• 1989

This theory has fast response and low overshoot by transforming its structure and this system may have new character which did not appear in this system. The VSS system transform its structure by switching logic. Then, the state trajectory is to sliding along the switching line to the phase-plane orgin. The phase trajectory is known as the sliding mode of this controller. This paper performed position control in the theory and analysised the change in variable loads.

• 한국광학회:학술대회논문집
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• 한국광학회 2005년도 제16회 정기총회 및 동계학술발표회
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• pp.186-187
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• 2005