• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.153-154
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• 2015

Voltage Source Converter HVDC (VSC-HVDC) are a better alternative than conventional thyristor based HVDC systems. Unfortunately, VSC-HVDC's full potential cannot be utilized up till now due to absence of suitable HVDC protection. Recently, hybrid HVDC circuit breakers (HDCCB) have been developed and successfully lab tested. However, their application and feasibility in VSC-HVDC needs to be investigated. In this research paper we have modelled an existing HDCCB and evaluated its impact on fault reduction and interruption in VSC-HVDC systems. The HDCCB was applied in Korean Jeju-Haenam VSC-HVDC system model and its impact was analyzed for HVDC line-to-ground and line-to-line faults. HDCCB successfully interrupted the fault current and prevented the damages to costly IGBTs and converter transformers.

• 동력기계공학회지
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• 제7권3호
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• pp.23-28
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• 2003

In heavy nuclear power plant, high energy through main steam line is provided to turbine that generate the electric power. Since plant had generated power, high noise has been occurred. Noise make equipments and work environment worse. For finding out the location and the cause of making noise, noise was measured along main steam line at open/close test of Main Steam Isolation Valve (MSIV hereafter). As the result, it was identified that the vortex shedding in the cavity of MSIV is main noise source. The profile change of MSIV seat ring was proposed as the method of noise reduction. After filletting MSIV seat ring, the noise level reduced $10{\sim}20dB$ compared before the change of profile.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1490-1493
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• 2009

In this work we present a new type of line plasma source using an internal-type ICP operated at 2MHz with a ferrite module, describe the effect of ferrite module on the enhancement of the plasma properties and the uniformity, and compare to those obtained with 13.56MHz discharge. Also the electrical characteristics of the antenna line and the characteristics of the plasma uniformity were studied.

• 한국정보전자통신기술학회논문지
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• 제1권2호
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• pp.21-25
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• 2008

A CCFL which commonly used in the back light units for the LCD, possess very high brightness hence, was widely used as a line light source. However, the use of CCFL, caused for several environmental concerns since it contain highly toxic mercury, gradually replaced into a LED. But the LED is a spot light source, the dark area occurs in the surface of the back light units. In this paper, we proposed the lens that can convert the spot light into the line light and it can remove the dark area in the surface of the back light units. The lens is composed with the light condensation part and the light guiding part. The conditions obtained will be helpful to plan an optimum structure for such preparation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.446-448
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• 1995

This paper dscribes a detail simulation model with EMTP (Electro-Magnetic Transients Program) which is very effective to analyze the interaction between the ac transmission line and STATCON (static condenser). The SATCON was represented by two voltage-source converters connected in parallel and sharing an energy storage dc capacitor bank. The voltage source converters was modeled with ideal gate turn-off switches. The power system was represented by a detail generator model and a distributed tramnsmission line model for detail performance analyses. Analysis results show that the conceived simulation model is very effective to analyze the interaction between the ac transmission line and STATCON, and to evaluate the performance of STATCON.

• 디지털콘텐츠학회 논문지
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• 제9권4호
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• pp.551-560
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• 2008

디지털 영상콘텐츠 분야에서의 원소스 멀티유스(One-Source Multi-Use) 전략은 하나의 소재(onesource)로 다양한 상품(multi-use)을 개발, 배급할 경우 시장에서의 시너지효과가 크다는 판단에 의해 서로 다른 장르에 적용하여 파급효과를 노리는 마케팅관점에서 중시된 이론으로 알려져 있다. 최근 문화산업재의 온라인화 및 디지털 콘텐츠화가 급진전되고 각 장르간 경계가 모호해지고 매체간 이동이 용이해짐에 따라 이 전략은 창구효과(Window Effect)가 큰 문화산업의 특성에 맞추어 기획 단계부터 영화 게임 애니메이션 캐릭터 등을 총 망라하는 문화 콘텐츠를 개발뿐만 아니라 플랫폼 재활용측면에서 소프트웨어엔지니어링 분야까지 확장되고 있는 추세이다. 특히 하나의 인기 소재만 있으면 추가적 비용부담을 최소화하면서 다른 상품으로 전환해 높은 부가가치를 얻을 수 있다는 점에서 각광받고 있으며, 관련 상품과 매체를 체계적으로 관리할 수 있어 마케팅 및 홍보 플랫폼 제작 등에서 제작비용 절감효과를 누릴 수 있다는 장점이 있다. 이러한 관점에서 본 연구는 세계적으로 영상콘텐츠산업 비중이 높은 한 미 일 3국의 제작방식의 비교를 통하여 각국이 선호하는 장르 및 제작방식을 고찰하고자 한다.

• 한국해안해양공학회:학술대회논문집
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• 한국해안해양공학회 2004년도 학술발표논문집 Proceedings of Coastal and Ocean Engineering in Korea
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• pp.73-84
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• 2004

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.1008-1011
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• 1998

Output of arc welding power source can be evaluated dynamically and also statically through an arc simulator. The arc simulator is developed to simulate the arc load of short circuit and arc and return power to the line.

• The Journal of the Acoustical Society of Korea
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• 제22권2E호
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• pp.78-86
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• 2003

We analyzed the measured acoustic field to explore the characteristics of a horizontal coherence in shallow water. Signal spatial coherence data were obtained in the continental shelf off the east coast of Korea using a horizontal line array. The array was deployed on the bottom of 130 m water depth and a sound source was towed at 26 m depth in the source-receiver ranges of 1-13 ㎞. The source transmitted 200 ㎐ pure tone. Topography and temperature profiles along the source track were measured to investigate the relationship between the horizontal coherence and environment variations. The beam bearing disturbance and array signal gain degradation is examined as parameters of horizontal coherence. The results show that the bearing disturbance is about ± 8° and seems to be affected by temporal variations of temperature caused by internal waves. The array signal gains show degradation more than 5㏈ by the temporal and spatial variations of temperature and by the down-sloped topography.

• 한국식품영양학회지
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• 제24권2호
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• pp.217-225
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• 2011

The current research identified the impacts of WOM(Word-of-Mouth) regarding dining experience and the factors which were likely to influence them. Specifically, this study is examined from the perspective of WOM recipient's in on-line settings. For the purpose of this research, online survey was used and a total 203 online questionnaires of respondents who had experienced restaurant reviews and recommendations via internet last 6 month were analyzed. Overall, the results indicated that in aspects of WOM recipients, the impacts of WOM were 'visit intention', 're-WOM intention' and 'source credibility' affected 'WOM acceptance' in this process. Additionally, 'online homophily' and 'message vividness' had a positive effects(p<0.001) on builiding source credibility. By clarifying the process between on-line WOM of restaurant consumers and their actual visit, this study intend to provide basis which can be used for restaurant industry's effective marketing activity.