• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.505-509
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• 1997

Praseodymium-based ZnO varistor containing 2.0mol% and 4.0mol% $Y_2$O$_3$ were fabricated, respectively and its microstructure and electrical properties were investigated. Yttrium distributed nearly in the grain boundaries and cluster phase at nodal point but more in cluster phase. The average grain size of the 2.0%mol% and 4.0mol% $Y_2$O$_3$-added samples was 14.8${\mu}{\textrm}{m}$ and 8.6${\mu}{\textrm}{m}$, respectively. Compared to 2.0mol% $Y_2$O$_3$, 4.0mol% $Y_2$O$_3$-added varistors showed very good I-V characteristics exhibiting highly nonlinear exponent(87.4) and low leakage current(46.7nA). These results are the important experimental fact in this paper.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2014년도 전력전자학술대회 논문집
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• pp.343-344
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• 2014

마이크로그리드에서 ESS용 PCS를 모듈화하면 용량의 확장성, 신뢰성 향상 등의 장점을 갖는다. 모듈화 된 인버터는 병렬구조를 갖고 인버터 모듈간의 접속점(PCC)에 공통으로 중요부하를 공유하고 있어 독립운전 시 정확한 부하분담이 요구된다. 또한 독립운전 및 계통연계 모드전환 시 제어기 변동으로 인한 과도상태로 인해 접속점에 연결된 중요부하에 악영향을 끼칠 수 있다. 따라서 본 논문에서는 ESS용 PCS로서 모듈화 된 병렬 인버터가 모드전환 시 과도상태가 없는 무순단 절체 기능을 갖는 마스터-슬레이브 제어알고리즘을 제안한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2015년도 전력전자학술대회 논문집
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• pp.199-200
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• 2015

The paper describes the development of Fast Charger by using Vienna Rectifier as AC/DC converter. The Vienna Rectifier is proven to have a high efficiency performance as well as a prominent power quality performance on AC side of the fast charger. The Vienna Rectifier is compared to other topology, especially T-type inverter, and analyzed carefully. Experimental results from a 10kW prototype are provided to validate the theoretical consideration.

• 한국실내디자인학회논문집
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• 제15권1호
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• pp.98-105
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• 2006

This study tries to find how architects interpret and express fashion brand images. First, it examines the concept of brand images and its architectural expression of them in contemporary commercial architecture. Second, it investigates the brand strategies and architectural expression strategies of world-famous fashion brand companies such as Prada and Louis Vuitton. Third, it finds out architects' expression of the brand strategies focusing on Rem Koolhaas, Herzog & do Meuron, Jun Aoki, Barthelemy-Grino, Kumiko Inui. In conclusion, architects have their own expression tools for fashion brand images but the extent of expression vanes according to each brand strategy.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2000년도 제32회 추계학술대회 정기총회
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• pp.115-121
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• 2000

The contaminant seperation performance of fitters has been widely investigated for many years. However, most of the proposed filter assessment techniques have proven disappointing for practical use. Although the Multipass (Beta) Filtration test method (ISO 4572) provides valuable information in assessing fi ters, it has a limitation on evaluating the increasing family of low-flow and high Beta filters. The limitation stems from two main sources: the over simplified theoretical model and the inherently complicated procedure in analysis of data. Hence a new advanced filtration theory, the Beta Prime developed on a draw-down test basis is applied to predict field operating characteristics of a filter for tractor hydraulic systems in this study.

• 한국BIM학회 논문집
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• 제13권1호
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• pp.33-40
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• 2023

In architectural design studios, students' needs are evaluated from a diverse and objective point of view. And the evaluation process and results are to use a design evaluation method that everyone can recognize. Therefore, in this study, we propose Crowdsourcing, in which a large number of participants participate in the evaluation to solve fundamental problems. However, the field of architecture is an area in which expertise such as evacuation, firefighting, rescue, and regulations is essential. Therefore, we expanded the concept by participation of a large number of architects, not the general public. And It presented a new word, Prowdsourcing. Prowdsourcing is a group of architects working on-line as an evaluator. It is a method that can have objectivity and expertise of evaluation at the same time. Therefore, prowdsourcing will provide students with a variety of objective assessments, which will be a recognized design evaluation method by everyone.

• 융합보안논문지
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• 제17권3호
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• pp.73-81
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• 2017

2009년 4월 미국 오바마 대통령의 프라하 연설을 계기로 국제사회는 핵안보 증진과 핵테러리즘 저지를 위해 2010년부터 2016년까지 4차례의 핵안보정상회의를 개최하였다. 핵안보정상회의는 테러리스트들이 핵무기 또는 핵 분열성 물질의 획득 노력을 저지하기 위한 중대한 진전을 이루었으나 여전히 한계와 문제점을 남겼다. 이를 해결하기 위한 향후 국제 사회의 과제는 첫째, 양자간 협력과 다자간 핵안보 레짐 강화를 위한 공동의 노력을 재개하고, 참가국은 자국의 핵물질 방호와 핵시설 보안을 위한 공약 이행을 위해 노력해야한다. 둘째, 4차 핵안보정상회의에서 채택된 5개 행동계획에 따라 유엔, 국제원자력기구, 국제형사경찰기구(인터폴), 세계핵테러방지구상, 글로벌파트너십은 지속적인 핵안보 증진을 위해 임무를 수행해야한다. 셋째, 참가국들은 핵안보정상회의에서 다루지 못했던 군수용 핵물질의 관리와 방호에 대한 논의를 시작해야한다. 넷째, 핵안보의 국제법적 기반인 개정 핵물질방호협약과 핵테러억제협약의 이행을 강화하고, 핵시설에 대한 사이버 공격 대비 및 핵물질의 도난 불법거래 사보타주 저지를 위해 노력해야한다.

• 한국실내디자인학회논문집
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• 제27권2호
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• pp.12-23
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• 2018

The purpose of this study is to examine the innovative and experimental housing design alternatives in the transition period to the modern era and to discuss about the motivation of modern architectural form. Thus, first, this study examined the planning concepts and the meaning of new design of the four Werkbund dwelling Exhibitions in eastern Europe reflecting the demands of modern times. Second, I analyzed how the formative experiment appeared as a stereoscopic mass design and as a architectural composition in exterior. Experimental trials at housing exhibitions were to respond to the demands for the new forms, which required a new approach to modern style and aesthetics. The major features of formative experiments can be summarized as follows. First, new housing design have escaped from the historically descended style. Secondly, through the operation of volume and surface modern dwelling created a formative conformation. Finally, the shape and the surface replaced the decoration. In conclusion, the works of modern architects can be said to have achieved the harmony between 'purpose of expression' and 'technical purpose' in realizing the 'Zeitgeist' that corresponds to the paradigm of modern housing.

• 전력전자학회논문지
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• 제21권5호
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• pp.373-380
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• 2016

In this paper, a 50-kW high-efficiency modular fast charger for both electric vehicle (EV) and neighborhood electric vehicle (NEV) is proposed. The proposed fast charger consists of five 10-kW modules to achieve fault tolerance, ease of thermal management, and reduce component stress. Three-level topologies for both AC-DC and DC-DC converters are employed to use 600V MOSFET, resulting in ease of component selection and increase in switching frequency. The proposed three-level DC-DC converter with coupled inductor and its hybrid switching method can reduce the circulating current under wide output voltage range. A 50-kW prototype of the proposed fast charger was developed and tested to verify the validity of the proposed concept. Experimental results show that the proposed fast charger achieves a rated efficiency of 95.2% and a THD of less than 3%.

• 한국안전학회지
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• 제16권1호
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• pp.48-52
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• 2001

This study was undertaken to investigate fire risk characteristics of the plastics foam that is used an insulating materials in workplaces. The ignition characteristics and combustion gas of the plastics foam were carried out using the ISO self-Ignition tester, the Cone Calorimeter, and NES combustion analyzer. The experimental materials used were commercial samples and their composition is not disclosed by the manufacturer. As the experimental results, the self-ignition temperature of the plastics foam ranges from $410^{\circ}C$ to $510^{\circ}C$, and the flash-ignition temperature of plastics foam ranges from $370^{\circ}C$ to $450^{\circ}C$. The difference of ignition temperature on density with plastics foam type was smaller since the amount of combustible gas to ignite is not caused enough. The time to ignition of the polyethylene foam in samples of the plastics foam was shorter, and its of polyethylene foam was longer. The concentration of carbon dioxide of the polyethylene foam shows higher in samples of the plastics foam. It is found that the concentration values of carbon monoxide of the plastics foam show very fatality on people during exposure of 30 minutes in fire.