• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.291-295
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• 2005

The PEMFC behavior is quite complex and is influenced by several factors, including composition and structure of electrodes and membrane type. Fabrication of MFA is important factor for proton exchange membrane fuel cell. MFA of PEMFC with hot pressing and direct coating method were prepared, and performances were evaluated and compared each other. The effect of MEA preparation methods, hot pressing methods and direct coating methods, on the cell performance was analyzed by impedance spectroscopy and SEM. The performance of PEMFC wi th direct coat ing method was better than wi th hot pressing method because membrane internal resistance and membrane-:-interfacial resistance were reduced by elimination of hot pressing process in MEA fabrication. In addition the micro structure of MEA with direct coating method reveals uniform interface between membrane and catalyst layer.

• The Korean Journal of Quaternary Research
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• v.8 no.1
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• pp.1-8
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• 1994

한국서해 경기만 남부 반월조간대 퇴적층에서 망간과구리의 함량특성을 밝히기 위 하여 총 3개의 주상시료를 채취하여 퇴적물의 입자와 유기탄소(organic carbon)함량을 일차 적으로 분석하였고 이에 따른 중요 시료에 대하여 망간과 구리의 함량을 분석하였다. 이러 한 분석결과는 연구지역의 망간함량이 연근해역 퇴적물의 망간함량에 비해 낮고 구리함량은 상대적으로 높다. 연구지역 내에서도 환원환경인 중부와 하부조간대에서 망간함량이 낮고 구리의 함량이 높게 나타났다. 이와같이 반월조간대 퇴적물의 망간 함량이 낮은 이유는 환 원환경에 공급괸 망간 산화물이 수 mm 깊이의 퇴적층에서 용해되고 그결과 생성된 용존 망간이 퇴적층과 해수와의 경계면(interface)으로 이동 제거 되었기 때문이다. 그러나 구리- 유기물 결합체는 퇴적물내에서 분해되고 그결과 생성된 용존구리는 황화물로 재 침전 되기 때문에 높은 함량을 나타내는 것으로 해석된다, 이와같은 결과는 반월 조간대 퇴적층의 초 기속작용의 영향을 받는 것으로 사료된다.

• Annual Conference on Human and Language Technology
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• 2018.10a
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• pp.417-421
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• 2018

The Universal Dependencies 프로젝트는 현재 71개 언어, 122개 Treebank로 이루어져 있으며, 병렬 언어 처리를 위해 여러 언어에 적용할 수 있는 형태적, 구문론적 특성을 찾는 것을 목표로 한다. 본고는 UD의 형태 태그셋인 Universal POS를 살펴보고, 한국어의 기존 형태 태그셋을 UPOS로 자동 변환하여 적용하는 방안을 제안한다. 영어와 같은 굴절어를 중심으로 구축된 UPOS 체계를 교착어에 속하는 한국어에 적용하기 위해서는 UPOS의 개별 표지와 21세기 세종계획 형태 주석 표지 결합체 간의 일대다 사상을 시도해야 한다.

• Journal of the Korean Data and Information Science Society
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• v.25 no.4
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• pp.745-753
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• 2014

Parrondo paradox is the counter-intuitive situation where individually losing games can combine to win or individually winning games can combine to lose. In this paper, we compare the history-dependent Parrondo games and the space-dependent Parrondo games played cooperatively by the multiple players. We show that there is a probability region where the history-dependent Parrondo game is a losing game whereas the space-dependent Parrondo game is a winning game.

• The Journal of the Korea Contents Association
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• v.11 no.1
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• pp.83-91
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• 2011

The attribute of cartoon and comics has been known the combination of image and text. It is improved the we find the shape of comics at the first comics on the newspaper. But we can read the comic without word. These works don't give the difficult to read and it may transfer to readers by the image of figure on comics. Therefore how can the image reach the readers by the communication. This study is the research of the visual image communication and the attribute of wordless comics.

• Journal of the Korean Ceramic Society
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• v.27 no.4
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• pp.548-552
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• 1990

Effects of binder addition method during compacting on microstructural change and magnetic characteristics of Sr-ferrite system was investigated. Used binders were PVA and PEG, which were added separately or simultaneously. After compacts were heated at 50$0^{\circ}C$ for 3hr in air for burning out all the binders, they were sintered at 125$0^{\circ}C$ for 2h. Based on results, in the case of using the two binders simultaneously, comparing to single binder system, compacted density was somewhat higher but sintered density was rather lower, and abnormal grain growth was accelerated. According to these sintering characteristics, remanent magnetization and coercive force were also diminished.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.11 no.1
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• pp.79-86
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• 2015

The purpose of this study is to evaluate structural integrity of a weldment which is partially screwed and then welded. Two finite element models are constructed and solved: operating temperature and internal pressure are considered in the first simple model, and welding process and normal operating condition including heat-up process are simulated in the second model. Structural integrity assessment criteria are satisfied with both finite element models, therefore the repair weldment finely sustains structural integrity of this assembly and prevents leakage. Stresses are dramatically increased when weld residual stress is considered, but it should be considered as a secondary stress.

• Journal of the KSME
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• v.28 no.2
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• pp.146-149
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• 1988

19세기의 기술시대 이후, 20세기 전반은 과학의 시대, 20세기 후반은 과학과 공학이 연합한 세 련된 기술의 창조시대였으며, 21세기는 정교한 공학과 과학의 지식이 요구되는 시대라고 한다. 이러한 논리는 현대공학이 기술주도와 과학주도 공학분야의 결합체로서, 공학적 수련(engineering practice)을 위해서는 과학이 원리에 기본을 둔 지시과 수련과 기술에 의하여 주도된 경험적 지 식을 모두 요구하고 있기 때문이다. 공학은 응용과학과는 다르며 과학적인 원리와 경험적 지 식을 사용하여 기술적인 해를 추구하는 방법임에도 불구하고 오늘날의 세계적인 공학교육의 추 세는 아직까지도 과학적 원리에 중점을 두어왔으며, 따라서 공학의 요체라 할 수 있는 수련과 기술에 의한 경험적 지식은 대학교육에서 도외시 되어온 반면, 많은 부분이 산업체에 축적, 존 재하게 되었다. 특히 현대의 고도기술 경쟁사회에 있어서 창의적 기술개발은 상대적 기술우위를 점하기 위해 필수적인 요소가 되고 있으며 '기술에는 과거가 있어도 기술자에게는 과거가 없고 오직 미래만이 있다'는 아이러니가 통용되고 있는 실정이다.

• Korean Journal of Microbiology
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• v.27 no.2
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• pp.108-116
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• 1989

Based on the specificty of recognition of the vacuolar arginine transporter, N-p-nitrobenzoxycarbonyl (NBZ)-L-arginyl diazomethane was synthesized and used as an affinity label specific for the arginine transporter. This arginyl derivative ingibited both ATP-dependent and independent L-arginine transport into vacuolar membrane vesicles. When vacuolar proteins were labeled with radioactive NBZ arginyl diazomethane, the binding was irreversible, detached by treatment with base and blocked by treatment with cysteinyl blocking groups suggesting cysteine as a labeling site.

• Journal of the korean Society of Automotive Engineers
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• v.12 no.4
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• pp.66-74
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• 1990

Friction between piston-ring assembly and cylinder wall of a spark ignition engine was evaluated under various engine operating conditions utilizing a grasshopper linkage system. The friction force was estimated by the force balance relation at the small end of connecting rod. Three forces were chosen to be measured for the objective. They were gas pressure inside the cylinder, inertia force of the piston-ring assembly, and the force exerted by the connecting rod. These forces were measured by a piezo type pressure sensor, an accelerometer and strain gauges, respectively. Comparisons were made with the frictional force evaluated by the conventional method where the assumption of constant rotational speed of engines was adopted. Due to the variation of rotational speed of engines, the conventional method was found to lead to a large error in the evaluation of the frictional force.