• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.16-17
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• 2005

Local lifetime control by ion implantation has become an useful tool for production of modern power devices. In this work, punch-through diodes were irradiated with protons for the high speed power diode fabrication. Proton irradiation was executed at the various energy and dose conditions. Characterization of the device was performed by I-V, C-V and Trr measurement. We obtained enhanced reverse recovery time characteristics which was about 45% of original device and about 73% of electron irradiated device. The measurement results showed that proton irradiation was able to effectively reduce minority carrier lifetime.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.3
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• pp.216-221
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• 2006

Lifetime control technique by proton implantation has become an useful tool for production of modern power devices. In this work, punch-through type diodes were irradiated with protons for the high speed power diode fabrication. Proton irradiation which was capable of controlling carrier's lifetime locally was carried out at the various energy and dose conditions. Characterization of the device was performed by current-voltage, capacitance-voltage and reverse recovery time measurement. We obtained enhanced reverse recovery time characteristics which was about $45\;\%$ of original device reverse recovery time and about $73\;\%$ of electron irradiated device reverse recovery time. The measurement results showed that proton irradiation technique was able to effectively reduce minority carrier lifetime without degrading the other characteristics.

• Proceedings of the Korea Contents Association Conference
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• 2017.05a
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• pp.59-60
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• 2017

중국은 다양한 소수민족으로 구성된 국가이다. 이처럼 풍부하고 다채로운 소수 민족문화는 애니메이션 창작 분야에서 무궁무진한 작품 소재로 사용되고 있다. 1980년대에 위구르족의 민간소재를 바탕으로 제작 된 스톱모션 애니메이션인 <아반티 이야기, 1979>는 위구르족의 문화와 전통을 잘 표현하였다. 이에, 본 논문은 스톱모션 애니메이션 기법으로 제작된 <아반티 이야기, 1979>에서 어떻게 위구르족의 문화와 전통 의상을 표현하고 중국문화와 연관성이 있는지, 그리고, 문화원형을 어떻게 현대적으로 해석하였는지 알아보고자 한다.

• Journal of the Korean Statistical Society
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• v.36 no.1
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• pp.175-182
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• 2007

The support vector machine has been successful in many applications because of its flexibility and high accuracy. However, when a training data set is large or imbalanced, the support vector machine may suffer from significant computational problem or loss of accuracy in predicting minority classes. We propose a modified version of the support vector machine using the K-means clustering that exploits the information in class labels during the clustering process. For large data sets, our method can save the computation time by reducing the number of data points without significant loss of accuracy. Moreover, our method can deal with imbalanced data sets effectively by alleviating the influence of dominant class.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.2
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• pp.247-253
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• 1989

The amino acid content and constitution of domestic flue-cured tobacco before and after the aging were investigated. The major amino acids of domestic flue -cured tobacco were histidine, serine, aspartic acid and proline and leucine, isoleucine and glycine were minority in them. Phenylalanine was the most changeable components through the aging. While the contents of tryptophan, sering and Proline which have herbaceous, harsh and bitter taste and aroma in smoke were reduced, tyrosine which adds smoothing and enhances smoke aroma was increased after the aging. The leaf tobacco aged at 4$0^{\circ}C$ for 30 days had a amino acid composition as good leaf tobacco storaged in natural condition for 2 years.

• The Journal of Internal Korean Medicine
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• v.39 no.5
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• pp.1068-1074
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• 2018

Objectives: Acute bronchitis is a common inflammatory disease with symptoms related to temporary inflammation of the airways. It is caused by a viral infections in over 95% of cases. A small minority of cases are caused by bacteria; however, there is little evidence that antibiotics are effective in the treatment of the condition. This report is a case of administering Dojukgangki-tang to three patients with acute bronchitis. Methods: Patients diagnosed with acute bronchitis were treated with Dojukgangki-tang, and the effects were studied using the bronchitis severity scale (BSS) and acute bronchitis severity scale (ABBS). Results: After treatment with Dojukgangki-tang for 2 weeks, average BSS score changed from $11.33{\pm}2.08$ to $1.67{\pm}1.15$. Average ABSS score decreased from $9.00{\pm}3.00$ to $2.00{\pm}1.00$. Conclusions: This study suggests that Dojukgangki-tang is effective in relieving coughs and sputum related to acute bronchitis.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.307-307
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• 2010

ICRF 또는 NB 시스템에 의해 가열된 고에너지 이온들을 측정하는 것은 핵융합 플라즈마에서 중요한 과제 중의 하나이다. 특히 ICRF를 이용한 D(H) 플라즈마의 H minority의 가열은 H의 분율에 따라 가열의 정도가 달라지고 이 결과는 이온의 고에너지 측정을 통해서 확인할 수 있으므로 정확한 고속 이온의 측정은 매우 중요하다. 본 연구에서는 고속 이온을 전하 교환된 중성입자로부터 측정하는 중성입자 검출기를 개발하였다. Si 광다이오드인 AXUV3ELA를 기반으로 50-300 keV 범위의 고에너지 H 및 D 이온을 측정할 수 있는 소형의 중성입자 검출기(Compact Neutral Particle Analyzer : CNPA)가 설계 제작되었다. 검출된 신호는 Pre-amp와 shaping amplifier를 통해 증폭되고 shaping 되며 마지막으로 다중채널 분석기(Multi Channel Analyzer : MCA)를 통해서 계수된다. 본 발표에서는 NPA의 구체적인 설계 특성과 함께 Am-241 gamma ray 선원을 이용한 NPA의 시험 및 보정결과를 보고할 예정이다.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.370-370
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• 2009

이종접합태양전지는 구조적 대칭성 때문에 웨이퍼 두께가 감소하여도 보우잉이 일어나지 않는 특징이 있으며, 산요에서 개발한 이종접합태양전지의 효율이 22% 이상을 보이고 있다. 이종접합태양전지에서 비정질 실리콘과 실리콘 웨이퍼의 계면에 따라 이종접합태양전지의 특성이 크게 변화한다. 본 연구에서는 패시베이션 층으로 사용되는 비정질 실리콘을 hot wire chemical vapor deposition(HWCVD)을 사용하여 이종접합태양전지에 적용하였으며 기존의 plasma-enhanced chemical vapor deposition을 이용한 비정질 실리콘을 적용한 이종접합태양전지와 비교하였다. 패시베이션 특성을 확인하기 위해 quasi-steady state photoconductance로 minority carrier lifetime을 측정하였고, 태양전지 특성평가로는 암전류특성 및 광전류특성을 사용하였다. HWCVD를 사용하여 패시베이션한 태양전지의 경우 16.1%의 효율을 보였다.

• Proceedings of the Korean Society for Language and Information Conference
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• 2007.11a
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• pp.146-154
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• 2007

AutoCor is a method for the automatic acquisition and classification of corpora of documents in closely-related languages. It is an extension and enhancement of CorpusBuilder, a system that automatically builds specific minority language corpora from a closed corpus, since some Tagalog documents retrieved by CorpusBuilder are actually documents in other closely-related Philippine languages. AutoCor used the query generation method odds ratio, and introduced the concept of common word pruning to differentiate between documents of closely-related Philippine languages and Tagalog. The performance of the system using with and without pruning are compared, and common word pruning was found to improve the precision of the system.

• Journal of Educational Research in Mathematics
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• v.8 no.2
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• pp.621-634
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• 1998

Emthusiasm about the introduction of computers into mathematics education is widespred. But, the perspectives about the relationship between mathematics education and computer are diverse. The purpose of this study is to examine theoretical background for using computers in mathematics education. In spite of the pedagogical possibilities of computers. only a small minority of mathematics teachers are using computers in mathematics classroom. It is natural to seek this obstacles within theoretical background of the teachers who manage computers, In this study, We discuss the problems in the two sides. First, due to increased computer activity, relationship of mathematics in school with mathematics in society is changing. It is tension between academic mathematics and practical mathematics. School mathematics have to be changed toward stressing practical mathematics. Second problem is the dialectical relationship between the individual and the collective. While maintaining a respect for the individuality of student contributions. We take into account the social dimension of mathematical meaning-making. We discussed theoretical clarification of work collaborative learning. We propose the case study for the roles of computer in collaborative mathematics learning.