• Journal of Korean Society for Atmospheric Environment
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• 제19권E1호
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• pp.21-28
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• 2003

An auxiliary device, called Post Cyclone (PoC). had been introduced and primarily examined in earlier works which proved the reduction of the emission of fine dust from the gas-solid cyclones without incurring significant increase of cost and pressure drop. It has been known that the PoC has some advantages over other secondary dust treatment devices such as (a) simple design, (b) low cost of manufacture, (c) minimum additional pressure drop, (d) high recoverbility of the product dust, and (e) simplicity of operation. Despite the potential advantage, however, lack of practical data confined its plausible application in wide areas. Thus, in this work, a few serial experiments were conducted in terms of a few operation conditions, and the particle trajectories throughout the cyclone set-up were visually analyzed by using a commercial computer simulation program (FLUENT).

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(1)
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• pp.327-331
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• 2003

This paper proposes a novel ZVZCS-PWM Boost Converter. It enables the main switch to be turned on and off with both zero voltage and zero current and the auxiliary switch to be turned on and off with ZCS, the rectify diode to be turned on and off with ZVS. Moreover, this converter is suitable for not on]y minority carrier device but also majority carrier device. The auxiliary resonant circuit of the proposed boost converter is placed out the main power path, therefore, there are no voltage/current stresses on the main switch and diode. The operation of the proposed boost converter is explained and analyzed theoretical and experimentally, from a prototype operating at 100kHz, with an input voltage rated at 50V.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2009년도 추계학술대회 논문집
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• pp.585-586
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• 2009

• 한국융합학회논문지
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• 제11권8호
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• pp.147-152
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• 2020

이 연구는 점차 증가하고 있는 젊은층과 여성 초보 골퍼들이 골프를 배워가는 과정에서 자세의 어려움, 골프 자체의 지루함, 더딘 실력 향상 등의 이유로 골프에 대한 흥미를 잃고 골프를 포기하는 사례가 많아 이를 보완하기 위한 보조기구를 개발하는 것이 목적이다. 이를 위해 먼저 골프채 그립 하단에 각종 센서를 탑재한 하드웨어 장치를 부착하여 골퍼의 스윙 자세와 비거리 등의 데이터를 수집, 전달할 수 있는 플랫폼을 설계하였다. 이후 이러한 데이터들을 분석, 보관할 수 있는 스마트폰 앱을 개발하고 연동하여 골퍼의 자세를 식별하고 자세를 스스로 교정할 수 있도록 하였다. 아울러 스마트폰 앱은 자기 비교와 타인 비교 콘텐츠를 통해 게임적 요소를 가미하여 초보 골퍼들의 지속적 운동참여를 위한 내적 동기부여도 제공할 수 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.209-212
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• 2003

This paper proposes a soft-transition control strategy for a three phase ZCS(Zero Current Switching) inverter circuit. Each phase leg of inverter circuit consists of an LC resonant tank, two main switches, and one auxiliary switches. This paper presents design consideration via a study example of a three phase prototype inverter for motor drives. A simple device tester with zero current switching capability is proposed to select eligible auxiliary switches. The principle of operation, feature and design considerations are illustrated and verified through the experiment with a 2.2kW 5kHz IGBT based experimental circuit.

• 전기학회논문지
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• 제64권1호
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• pp.57-63
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• 2015

Fault currents characteristics contain decaying DC offset. First cycle peak value of fault currents is higher than steady-state fault current value. These characteristics can affect the operation of protective device. To reduce the asymmetric fault current, the method using a series connection of two hybrid-type Superconducting Fault Current Limiter(SFCL) components, an auxiliary SFCL and a main SFCL, has been proposed. The auxiliary SFCL limits the first half cycle fault current, while main SFCL limits the steady state fault currents. This paper proposed a decision method of the optimal insertion resistance of auxiliary and main SFCL components. To verify the effectiveness of proposed scheme, the various simulations are performed by using Electromagnetic Transient Program(EMTP).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.155-158
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• 2004

This paper proposes a soft-transition control strategy for a three phase ZCS(Zero Current Switching) inverter circuit. Each phase leg of inverter circuit consists of an LC resonant tank, two main switches, and two auxiliary switches. This paper presents design consideration via a study example of a three phase prototype inverter for motor drives. A simple device tester with zero current switching capability is proposed to select eligible auxiliary switches. The principle of operation, feature and design consideration is illustrated and verified through the experiment with a 2.2kW 5kHz IGBT based experimental circuit.

• 조명전기설비학회논문지
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• 제17권4호
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• pp.100-105
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• 2003

본 논문은 새로운 보조 공진 DC 링크 스너버 회로를 제안하였으며, 실제적인 스위칭 소자 모듈의 유도 손실특성을 근거로 하여 전력손실의 저감에 대해 다루었다 보조 공진 DC 링크 스너버 회로를 이용하여 전압형 소프트 스위칭 3상 인버터의 회로정수값을 추종하였다. 그리고 실험과 시뮬레이션 결과에 의해서 3상 하드스위칭과 소프트스위칭 인버터의 전력 손실 해석을 하였다.

• 전기학회논문지
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• 제64권11호
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• pp.1639-1644
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• 2015

Auxiliary air compressor(ACM) applied to railroad cars is a device which controls amount of compressed air in order that pantographs can be mounted correctly on the roof of an electric train. Existing ACMs consist of dc motors and brushes wear out due to friction with a commutator. Therefore, continuous maintenance is required. However, three phase BLDC motors have higher power density compared to dc motors and the machine maintenance is not needed because electric commutation is possible. The three phase generally uses hall sensors to get position information and this enables the accurate control. This paper suggests an algorithm that compensates the errors occurred when the hall sensors have a breakdown for stable operation.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1440-1444
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• 2011

Memory-device is one of the auxiliary components of point-switch machine; connecting front-rod and tongue-rail. The right side and left side of memory-device are different from each other. When there would be a derailing accident of rolling stock or motor-car, the memory-device properly bends and protects the internal of point-switch machine. Memory-device is one of the important site maintenance spare parts. Memory-device for each of right and left side should be secured so that they can be installed on correct side during an exchange work. This study suggests the development of memory-device with different left and right side and the performance test of it. The study intends to contribute in the convenience improvement of maintenance by improving the unification of memory-device.