• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 학술대회 논문집
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• pp.237-240
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• 2004

For the paralleled operation of DC/DC converters, the current sharing between each modules is the most important for the reliability of the power system. Interleaving method is commonly used with many paralleling schemes for the reduction of the ripple in the output voltage of paralleled converters and there are many commercial IC for interleaving application appliable. But for all of them, it is impossible to detect the number of module in operating and then change the phase of them automatically. In this paper, a novel paralleling method is proposed for the converter parallel operation, which detects the number of modules in active and sets the phases of PWM signals applied to each modules autonomously. This can greatly improve the output voltage ripple and reliability of the system. The expandibility of modular number can be done very easily by just adding several parts.

• Journal of Power Electronics
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• 제14권4호
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• pp.788-795
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• 2014

This paper demonstrates the dynamic behaviors of paralleled high power IGBTs using trench and fieldstop technologies. Four IGBTs are paralleled and standard deviation is adopted to represent the imbalance. Experiments are conducted under three different operation conditions and at different temperatures ranging from $-25^{\circ}C$ to $125^{\circ}C$. The experimental results show that operation at very low and very high temperatures usually aggravates the switching behaviors. There is a trade-off between the balance and the losses at low temperatures. These results can help in the design of heat sinks in paralleling applications confronting very low temperatures.

• 항공우주기술
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• 제2권1호
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• pp.89-95
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• 2003

본 연구에서는 전력 컨버터를 병렬 사용하는 여러 가지 모듈화 방법과 전류제어 방법, 컨버터를 병렬 사용할 경우 발생하는 모듈 간 전류 불균형(current unbalance)의 원인과 해결 방법에 대해서 알아보며, 각각의 모듈화 방법의 장단점과 전류 제어방법의 특성을 해석한다. 기존의 모듈화 및 전류 제어방법에서 unregulated bus 방식을 사용하는 위성의 solar power regulator용 컨버터의 모듈화에 적용 가능한 응용 방법을 검토한다. 마지막으로 적용 가능한 응용방법을 2-병렬 모듈 컨버터에 적용하여 시뮬레이션과 prototype 제작을 통한 실험으로 적용 가능성을 확인한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.400-402
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• 2008

A new interleaved forward converter, adopting series-input parallel-output structure with a common transformer reset circuit, is proposed in this paper. Series-input structure distributes the voltage stress on switches, which makes it suitable for high input voltage application. Paralleling output stage with an interleaving technique enables the circuit handle large output current and reduces filter size. In addition, since two forward converters share one active-clamp circuit for the transformer reset, its primary structure is simplified. All these features make the proposed converter promising for high input voltage applications with high efficiency and simple structure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1015-1017
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• 2002

This is the study on static excitation system of synchronous generator of large capacity in new model, which was developed by KEPRI using triple redundant digital method, associate three bridges of thyristor phase controlled rectifier. This paper will discuss the design conception and the application results of system which includes the power control devices(thyristors, GTO) and power excitation potential transformer. The multi-paralleling thyristor bridge converters of N+1 method have firing circuit. The initial product manufactured by proposed design in the study is in commercial operation, completing installation and commissioning in 400MW Thermal Power Plant. The performance test is done in practical technique.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.220-222
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• 2007

With the wide spread of direct current (DC) electric railroads in Korea, the stray currents or leakage currents from negative return rails become a pending problem to the safety of nearby underground infrastructures. The most widely used mitigation method for this interference is the stray current drainage method, which connects the underground metallic structures to the rails with diodes (polarized drainage) or thyristor (forced drainage). Although this method inherently possesses some drawbacks, its cost effectiveness and efficiency to protect the interfered structures has been the main reason for the wide adoption. In this paper, we show the field test results for the application of stray current drainage system to a city gas pipeline paralleling a depot area of a metropolitan rapid transit system. The process for optimal positioning is briefly illustrated. The effectiveness of constant voltage, constant current, and constant potential drainage schemes was also described.

• 농촌계획
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• 제10권1호
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• pp.41-55
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• 2004

The purpose of this study is to investigate a causal relationship between the mode of production and change of rural society. While dominant theories of social change have stressed variation of contingencies and periodical contexts, this theoretical paper drives a new insight paralleling diverse theoretical arguments of each mode of production with rural and urban changes. Investigating the drifts of intellectual ideologies of the mode of production, we get through diverse paradigm shifts of the production accumulation and its trigger effects on rural change. More specifically, the present study investigates change of rural society by way of investigating such fluctuations of societal changes as ancient society, slavery society, feudal society, industrial society, post-industrial society, and information society. We find that transportation and communication technologies have had a key role in the changes, however, the effects of the technologies on social changes have been different between rural- and urban-society. While we take it for granted that flexible accumulation in post-industrial society and time-space compression and informatization in information society will reduce developmental gap between rural- and urban-society, we also found that there have been big differences of actual application of the technologies between theory and reality in each era of mode of production.

• 한국콘텐츠학회논문지
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• 제21권4호
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• pp.723-733
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• 2021

'리부트'와 '오마주' 방식은 드라마와 영화 등 전통적인 스토리텔링 분야에서 창작 기법으로 활용되고 있지만 트랜스미디어 스토리월드의 확장 유형의 가능성은 아직 제시되지 않았다. 본 연구는 '리부트'와 '오마주' 방식을 트랜스미디어 스토리월드 확장 유형의 새로운 개념으로 제시하는데 목적을 두고 있다. '리부트'와 '오마주' 방식은 끊임없이 콘텐츠를 발간하여야 하는 K-POP 아이돌 그룹의 대표적인 스토리텔링 방식으로 자리잡고 있다. 독자적인 스토리월드를 구축한 <엑소>,<방탄소년단>,<워너원>을 사례로 선정하여 서사 창작 부문과 마케팅 활용 부문을 함께 살펴보았다. 연구 결과는 다음과 같다. 첫째, 기존의 스토리 리부트 사례인 엑소는 기존 설정을 '과거'로 만들어 새로운 스토리라인을 삽입하는 형식을 취하고 있다. 둘째, 캐릭터의 리부트는 방탄소년단 사례로서 '아이돌 방탄소년단'과 '캐릭터 방탄소년단'을 병행하여 스토리월드를 구축했다. 셋째, 기존 스토리월드의 오마주는 워너원의 사례로 <프로듀스 101>의 스토리월드를 재구성하며 기존 향유층을 자연스럽게 끌어오고 있다. 넷째, 타 미디어 오마주는 방탄소년단 사례로 고전 작품의 의미를 방탄소년단의 캐릭터와 스토리월드로 재해석하여 보여준다.