• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권3호
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• pp.104-109
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• 1999

In order to design and predict the performance of the harmonic side drive motor, it is necessary to analyze the torque generated by the structure. In this paper, an analytical model is proposed for design. Conformal mapping is used to model the capacitance and torque of the motor as a function of the rotor angular position with two-dimensional approximation. Then the result of conformal mapping analysis is verified with F.E.M result.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.86-89
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• 1991

In recent years, Vacuum Circuit Breaker(VCB) has been widely used to enhance the confidence and at the same time to ease maintenance of waterworks requipment as the power supply breaker of high voltage motor. When making and breaking the sources as VCB the powerful surge voltage, repetitive reignition phenomenon resulted from exceeding inter-pole endurance voltage of CB, has occured. It has transmitted to the winding of motor stator through the cable, and this surge voltage is repeated over and over again before finishing making and breaking action of CB according to cumulation of repetitive reignition surge, motor has become burned in the end. This paper describes surge voltage occuring in making and breaking of VCB as circuit parameters by transient phenonenon and examines closely the variance of peak values, wavefront-length, wavetail-length, when changing inductance and capacitance of a cable. Finally we will expect to protect motor winding breakdown from surge voltage through parallel connection of suitable-size in the motor.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2017년도 춘계학술발표대회
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• pp.885-888
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• 2017

In this paper, a new strategy for estimating building temperature based on the modified resistance capacitance (R - C) network thermal dynamic model is proposed. The proposed method gives accurate indoor temperature estimation using minimum variance finite impulse response filter. Our study is clarified by the experimental validation of the proposed indoor temperature estimation method. This experiment scenario environment is composed of a demand response (DR) server and home energy management system (HEMS) in a test bed.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.811-814
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• 2004

Radiated noise from high frequency transformers (HTFs) of switching mode power supply is mainly caused by the leakage inductance and the parasitic capacitance of HTFs. Generally, the radiated noise can be reduced by adding snubbers to switching power circuits or shielding HTFs. Radiated noise, however, is mainly affected by the shielding method. In this paper, the various shielding methods to reduce the radiated noise of EMI are analyzed, compared in the experimental studies. And it is proved that the radiated noise can be reduced according to the shielding methods of HFTs and the electrical connection between shields and power circuit.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 춘계학술대회 논문집 전기설비전문위원
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• pp.63-65
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• 2006

A electrical fault is defined as any abnormal condition caused by a reduction in the insulation strength. To define the potential risk of the electric installation, measurement of leakage current has been getting considered, but because the measured leakage current value also contained leakage current by capacitance, the measured value could not be adapted to absolute reference to the installation. Therefore, in this paper, the correlation between the condition of electric installation and leakage current were analyzed. The result focuses on to detect them in a cost efficient way.

• 대한전자공학회논문지
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• 제27권5호
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• pp.737-746
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• 1990

Ga0.47In0.53As PIN photodiodes(PD) having various areas have been fabricated by liquid phase epitaxial techniques. Ternary melt has been baked out at 675\ulcorner in H2 atmosphere for 20 hours before growth, which resulted in reduction of background carrier concentration of grown epi-layer. Also, lattice mismatch has been controlled within 0.01%. The room temperature performance of 10**-4cm\ulcornerarea PIN PD at a bias voltage of -5V were` quantum efficiency(with no antireflection coating)=60% for 1.3\ulcorner light source, dark current\ulcorner5nA, and capacitance\ulcornerpE. Frequency response measurement of packaged PIN PD has shown that cut-off frequency (f-3dB) was 961MHz. This PD has shown a good eye pattern when it was incorporated in a 565Mbps optical receiver.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.913-916
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• 2006

The improvement of luminous efficacy is one of the major issues in PDP industry. In this work, we propose the new driving method for high efficiency AC-PDP and analyze its discharge characteristics. The suggested method can control the effective capacitance of panel by external auxiliary capacitor. External capacitor induces reduction of gap voltage proportional to the panel current, this in turn modifies the transient behaviour of discharge. The peak current level is reduced and the discharge duration is increased. As a result of these modifications, the luminous efficacy is enhanced by about 200% compared with the conventional driving method

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1014-1017
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• 2006

Admittance Spectroscopic analysis was applied to study the effect of LiF buffer layer and to model the equivalent circuit for $ITO/Alq_3/LiF/Al$ device structure. The admittance spectroscopic analysis of the devices with LiF layer shows reduction in contact resistance $(R_C)$, parallel resistance $(R_P)$ and increment in parallel capacitance $(C_P)$.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.583-584
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• 2008

This paper presents a low-power and high-speed pulsed flip-flop based on dual-precharging and conditional discharging. The dual-precharging operation minimizes the parasitic capacitance of each precharge node, resulting in high-speed operation. The conditional-discharging operation minimizes the redundant transitions of precharge nodes, resulting in low-power operation. Linear feedback shift register (LFSR) designed in a $0.18{\mu}m$ CMOS technology using the proposed flip-flop achieves 32% power reduction as compared to conventional design.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.263-268
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• 1997

Development of a high speed feed drive system has been a major issue for the past few decades in machine tool industries. The reduction of tool change time as well as repid travel time can enhance the productivity. However,the high speed feed drive system generates more heat in nature,which leads to thermal expansion that has adverse effects on the accuracy of machined part. The paper divides the feed drive system into the ball screw and guide way. For each part, the thermal behvior model is separtately developed to estimate the position error of the respective feed drive system that is caused by the thermal expansion. The modified lumped capacitance method is used to analyze the linear position error of the ball screw. The thermal deformation of guide way parts affects the straightness and angular error as well as linear position error. Finite element method is used to estimate the thermal behavior of these guide way parts. The effectiveness of the proposed models are verified through the experiments using laser interferometer.