• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.39-42
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• 2006

a current stress reduction technique for a boost integrated half-bridge (BIHB) DC/DC converter with voltage doubler type rectifier is proposed for digital car audio amplifier application. In the proposed circuit, two external capacitors are added parallel to the rectifier diodes in the secondary side of the transformer to shape the primary and the secondary current like rectangular waveforms in every switching instance. The experimental results of a 200W industrial sample show that the peak primary current decreases about by 10A. Thus, the proposed technique shows improved high efficiency.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.81-83
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• 2006

The conventional cold cathode fluorescent lamp (CCFL) driver for LCD TV has a transformer for each lamp to step up the high sinusoidal waveform from the low input voltage. The transformer used in the conventional topology causes the driver to have bulky size and high cost. This paper proposes a new transformer-less CCFL driver for LCD backlight that is based on the parallel-loaded resonant inverter topology. This resonant topology enables the circuit to supply enough high voltage for CCFL without a transformer. Also, with current-balancing technique, this transformer-less inverter drives 16 CCFL lamps.

• 한국통신학회논문지
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• 제14권6호
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• pp.675-685
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• 1989

상호접송망은 병렬처리 시스템에서 매우 중요한 부분이다. 최근 다단상호 접속망에 대한 연구가 많이 행해지고 있다. 본 논문에서는 회선스위칭 다단상호접속망의 시뮬레이션 방법을 확장하여 분할된 ADM/IADM 접속망의 성능 평가를 하였다. 시뮬레이션 데이터에 의하여, 적용된 분할 방법에 의한 접속망 성능과 접속망에서 사용된 저지처리방식에 의한 접속망 성능 간의 관계를 보였다. 분석 결과, hold 방식을 사용하는 IADM 접속망이 RST 면에서 가장 나은 접속망 동작을 보이는 것으로 나타났다.

• Journal of Power Electronics
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• 제12권2호
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• pp.258-267
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• 2012

An interleaved single-stage AC/DC converter with a boost converter and an asymmetrical half-bridge topology is presented to achieve power factor correction, zero voltage switching (ZVS) and load voltage regulation. Asymmetric pulse-width modulation (PWM) is adopted to achieve ZVS turn-on for all of the switches and to increase circuit efficiency. Two ZVS half-bridge converters with interleaved PWM are connected in parallel to reduce the ripple current at input and output sides, to control the output voltage at a desired value and to achieve load current sharing. A center-tapped rectifier is adopted at the secondary side of the transformers to achieve full-wave rectification. The boost converter is operated in discontinuous conduction mode (DCM) to automatically draw a sinusoidal line current from an AC source with a high power factor and a low current distortion. Finally, a 240W converter with the proposed topology has been implemented to verify the performance and feasibility of the proposed converter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1919-1921
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• 2002

In this paper, we were designed the ferroelectric phase shifter using 3-dB, $90^{\circ}$ branch-line hybrid coupler with two ports terminated in symmetric phase-controllable reflective networks. The design of phase shifter is based on reflection theory of terminating circuits. In order to find the optimum conditions of reflect phase, the effect of a change of capacitance and transmission line connected with two coupled ports of a coupler have been investigated. To obtain more accurate design parameters, finite element method is applied. We were showed large phase variation with small capacitance variation in the parallel connection of capacitor and transmission line by using EM-simulation and circuit-simulation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.147-150
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• 2002

HPSL(High Pressure Sodium lamp)have attracted much attention in recent years, because they offer high luminous efficiency and very long life. Recently, AC-DC converters have been widely as power factor improvement circuits in the power conversion equipment An application of the ZVT-PWM(Zero Voltage Transition Pulse Width Modulation) boost converter, which has great advantage on miniaturization and high power density, to the power factor improvement circuit of the HPSL inverter are described to identify the power factor correction characteristics of the inverter. In this paper the series-parallel resonant inverter(electronic ballast) for driving a HPS lamp is discussed. Finally, a power factor corrector is cascaded in front of the electronic ballast. Consequently, a high power factor above 0.99 and low THD on the line current can be achieved.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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• pp.33-35
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• 1999

This paper describes the test results of the single phase 3kVA high temperature superconducting power trans-former. The tapes are made with Bi-2223 and have silver alloy as the matrix. Four double pancake windings are used in total. Among them two double pancake windings are connected in series for high voltage winding and two double pancake windings are connected in parallel for low voltage winding. The rated voltages of each winding are 220/110 V. Fundamental characteristics are obtained through short circuit and no load tests. The over load capability and characteristics are investigated.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2006년도 한국컴퓨터종합학술대회 논문집 Vol.33 No.1 (A)
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• pp.403-405
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• 2006

Boolean 회로는 parallel 알고리즘을 위한 단순하면서도 실제적인 모델이다. Chung & Lee은 Boolean 회로 모델에서 볼록 이분할 그래프를 위한 최대 매칭을 찾는 O($log^2n+logn$ loglogn logb)depth와 $O(bn^3)$ size의 알고리즘을 제시하였다. 본 논문에서는 prefix compulsion 및 ASCEND, odd-even-merge의 방법을 이용하여 이를 개선한 O($log^2n$ logb) depth, O($bn^2$ logn) size의 최대 매칭 알고리즘을 제시한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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• pp.433-434
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• 1988

Rectangular microstrip antenna with parasitic element is analyzed. Radiation admittance and equivalent circuit parameters between rectangular microstrip antenna and parasitic element are obtained by using equivalent ${\pi}$-network parameters of the slit in the wall of the parallel plate waveguide filled with homogeneous dielectric. The return loss is calculated and measured as a function of frequency with gap width 0.5mm between the patch and parasitic element. The experimental results are in fairly agreement with calculated values.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권4호
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• pp.212-218
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• 1999

A new partial resonant three phase boost converter with high power factor and high efficiency is proposed. The proposed boost converter is constructed by using a resonant network in parallel with the swithch of the conventional boost converter. The devices are switched at zero voltage or zero current eliminating the switching loss. A new auxiliary partial resonant boost converter achieves zero-voltage switching(ZVS) or zero-current switching(ZCS) for all switch devices without increasing their voltage and current stresses.