• 세라미스트
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• 제21권4호
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• pp.349-365
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• 2018

Since the electrification of vehicles has been extended, solid-state batteries have been attracting a lot of interest because of their superior safety. Especially, polymer, sulfide, and oxide based materials are being studied as solid electrolytes, and each type of materials has advantaged and disadvantages over others. Oxide electrolytes has higher chemical and electrochemical stability compared to the other types of electrolytes. However, ionic conductivity isn't high enough as much as that of organic liquid electrolytes. Also, there are many difficulties of fabricating solid-state batteries with oxide based electrolytes because they require a sintering process at very high temperature (above ${\sim}800^{\circ}C$). Herein, we review recent studies of solid-state batteries with oxide based electrolytes about the ionic conductivity, interfacial reactions with Li metal, and preparation of solid-state cell.

• 센서학회지
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• 제30권3호
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• pp.170-174
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• 2021

As the rising attention to the medical and healthcare issue, Bio-MEMS (Micro electro mechanical systems) platform such as bio sensor, cell culture system, and microfluidics device has been studied extensively. Bio-MEMS platform mostly has high resolution structure made by biocompatible material such as polydimethylsiloxane (PDMS). In addition, three dimension structure has been applied to the bio-MEMS. Lithography can be used to fabricate complex structure by multiple process, however, non-rectangular cross section can be implemented by introducing optical apparatus to lithography technic. X-ray lithography can be used even for sub-micron scale. Here in, we demonstrated lines with round shape cross section using the tilted gold absorber which was deposited on the oblique structure as the X-ray mask. This structure was used as a mold for PDMS. Molded PDMS was applied to the cell culture platform. Moreover, molded PDMS was bonded to flat PDMS to utilize to the sub-micro channel. This work has potential to the large area bio-MEMS.

• 소성∙가공
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• 제31권5호
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• pp.267-272
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• 2022

A dual-phase structure refers to a material with two different phases of components or crystal structures. In this study, we analyze the stress distributions for harmonic and composite structured materials which are a kind of dual-phase structure materials. The finite element method (FEM) was used to progress compression test to analyze the strain distribution, and rather than constituted of a fully dense material, a dual-phase structure was designed to make a lightweight structure that has different shapes and volumes of vacancy in each case. As a result of each case, the dual-phase structured materials showed different stress distribution patterns and based on this, the cause was identified through the research.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 2019년도 제31회 한글 및 한국어 정보처리 학술대회
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• pp.460-464
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• 2019

번역 품질 예측은 기계번역 시스템이 생성한 번역문의 품질을 정답 번역문을 참고하지 않고 예측하는 과정으로, 번역문의 사후 교정을 위한 번역 오류 검출의 역할을 담당하는 중요한 연구이다. 본 논문은 문장 수준의 번역 품질 예측 문제를 HTER 구간의 분류 문제로 간주하여, 번역 품질 말뭉치의 HTER 분포 불균형으로 인한 성능 제약을 완화하기 위해 인조 사후 교정 말뭉치를 이용하는 방법을 제안하였다. 결과적으로 HTER 분포를 균등하게 조정한 학습 말뭉치가 그렇지 않은 쪽에 비해 번역 품질 예측에 더 효과적인 것을 보였다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2015년도 추계학술논문요약집
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• pp.269-270
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• 2015

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2016년도 추계학술논문요약집
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• pp.133-134
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• 2016

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2016년도 추계학술논문요약집
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• pp.135-136
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• 2016

• 대한금속재료학회지
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• 제46권12호
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• pp.788-799
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• 2008

This study is concerned with the effects of Mo, Cr, and V addition on tensile and Charpy impact properties of API X80 linepipe steels. Four kinds of steels were processed by varying Mo, Cr, and V additions, and their microstructures and tensile and Charpy impact properties were investigated. Since the addition of Mo and V promoted to form fine acicular ferrite and granular bainite, while prohibiting the coarsening of granular bainite, it increased the strength and upper shelf energy, and decreased the energy transition temperature. The Cr addition promoted the formation of coarse granular bainite and secondary phases such as martensite-austenite constituents, thereby leading to the increased effective grain size, energy transition temperature, and strength and to the decreased upper shelf energy. The steel containing 0.3wt.% Mo and 0.06wt.% V without Cr had the highest upper shelf energy and the lowest energy transition temperature because its microstructure was composed of fine acicular ferrite and granular bainite, together with a small amount of hard secondary phases, while its tensile properties maintained excellent.

• Composites Research
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• 제19권6호
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• pp.23-31
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• 2006

나노허니컴 구조물의 영률, 굽힘 탄성 계수. 공칭파괴강도를 구하였다. 양극산화 알루미늄은 잘 정렬된 나노허니컴 구조물의 일종으로서 공정이 간단하고, 높은 종횡비, 자가 정렬된 기공구조를 가지고 있고, 기공의 크기를 조절할 수 있다. 원자현미경으로 외팔보 굽힘 시험을 수행하였고 나노-UTM을 이용한 3점 굽힘 실험결과와 비교하였다. 또한 나노-UTM으로 인장시험을 수행하였다. 나노허니컴 구조물의 한쪽 면은 막혀 있어서, 일반적인 샌드위치 구조물의 면재에 비유될 수 있다. 하지만 이러한 막힌 면은 굽힘 강도 증가에 영향을 끼치지 못하고 균열선단으로 작용한다는 것을 알 수 있었다. 본 연구로 나노허니컴 구조물을 설계하는데 기초적인 물성을 제공하고자 한다.

• 정보과학회지
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• 제28권4호
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• pp.45-48
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• 2010

본 가고문은 2008년 개편한 포항공과대학교 컴퓨터공학과 학부 교과과정을 소개한다. 교과과정 개편의 배경과 방향을 설명하고 구체적인 교과과정 내용을 살펴봄으로써 교과과정 설계의 철학음 전달하고자 한다. 그리고 개편한 교과과정의 주요 과목을 소개하고 교과과정 개편의 의의를 정리한다.