• ETRI Journal
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• 제25권5호
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• pp.412-417
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• 2003

Using a galvanostatic charge/discharge cycler and cyclic voltammetry, we investigated for the first time the electrochemical properties of iron-containing minerals, such as chalcophanite, diadochite, schwertmannite, laihuite, and tinticite, as electrode materials for lithium secondary batteries. Lithium insertion into the mineral diadochite showed a first discharge capacity of about 126 mAh/g at an average voltage of 3.0 V vs. $Li/Li^+$, accompanied by a reversible capacity of 110 mAh/g at the 60th cycle. When the cutoff potential was down to 1.25 V, the iron was further reduced, giving rise to a new plateau at 1.3 V. Although the others showed discharge plateaus at low potentials of less than 1.6 V, these results give an important clue for the development of new electrode materials.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.37-40
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• 2006

In these days, as building structures are getting taller, larger, and more diversified, structural systems with more economy and more efficiency are being required and so are more efficient building materials. this study conducted a basic experiment to conclude an adequate selection of materials and to calculate an optimal mixing proportion of those materials to produce High-strength concrete in a 130MPa of specified concrete strength. And also we conducted an experiment to find out basic properties of this concrete such as slump-flow, strength.

• 한국초전도ㆍ저온공학회논문지
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• 제13권2호
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• pp.29-32
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• 2011

The thermal properties of insulation material are essential to develop a high-temperature superconducting (HTS) power cable to be operated at around liquid nitrogen temperature. Unlike metallic materials, nonmetallic materials have a high thermal resistance; therefore special attention needs to be paid to estimate heat flow correctly. Thus, we have developed a precise instrument for measuring the thermal conductivity of insulating materials over a temperature range from 40 K to near room temperature using a cryocooler. Firstly, the measurement of thermal conductivity for Teflon is carried out for accuracy confirmation. For a supplied heat flux, the temperature difference between warm and cold side is measured in steady state, from which the thermal conductivity of Teflon is calculated and compared with published result of NIST. In addition, the apparent thermal conductivity of Polypropylene laminated paper (PPLP) is presented and its temperature dependency is discussed.

• 대한기계학회논문집
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• 제14권1호
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• pp.23-36
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• 1990

본 연구에서는 Iosipescu의 전단 시험법을 사용하여 직접 측정한 응력 프린지 치(ｆ$_{LT}$ )와 Sampson의 응력-광법칙에 의하여 구한 ｆ$_{LT}$ 와 서로 비교하여 Sampson의 응력-광법칙이 ｆ$_{LT}$ 를 간접적으로 측정하는데 사용할 수 있는가를 확 인한다. 그리고 직교 이방성 재료를 광탄성 실험에 의하여 해석하는 경우에 필요한 기본물성치와 응력 프린지치 관계를 구하여 이 관계가 상온과 고온에서도 성립하는가 를 확인하고 또 직접 물성치를 측정하는 대신에 각 물성치에 대응되는 응력 프린지치 에 의하여 물성치를 구하는 방법을 개발하는데 이 연구의 목적을 둔다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2001년도 추계 학술발표강연 및 논문개요집
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• pp.167-167
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• 2001

• 한국재료학회:학술대회논문집
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• 한국재료학회 2001년도 춘계학술발표강연 및 논문개요집
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• pp.138-138
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• 2001

• 한국재료학회:학술대회논문집
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• 한국재료학회 1996년도 재료학회 춘계학술발표회
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• pp.7-7
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• 1996

• Bulletin of the Korean Chemical Society
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• 제26권1호
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• pp.165-168
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• 2005

• 반도체디스플레이기술학회지
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• 제18권3호
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• pp.77-81
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• 2019

Recently, Korea has been making efforts at the government level to overcome the national crisis that Japan's dependency on technology in the semiconductor and display materials sectors has also escaped due to export regulations on three materials carried out by Japan. Therefore, based on the data of the National Science & Technology Information Service (NTIS) operated by the government, we analyze the trend of R & D investment in the display field, thereby improving R & D to improve material technology competitiveness in the future. Let's examine the implications of investment. A total of 5 years of new research and development investment in the field of display was invested as basic research fund for 25%, 15% for applied research, and 53% for development research. In terms of development cost and development period, the basic research showed that the amount of money and the development period were shorter than that of applied research. In other words, the basic research accounted for 25% of the R & D investment and the average R & D period was only 3.2 years. As we can see from the recent development of H fiber carbon fiber, which was recently developed and entered full-scale production, we were able to succeed because of the benefits of government support for 10 years while giving the same material title differently. In order to escape from Japan's technological dependence on semiconductor and display materials in Korea, As such, basic research in the field of materials is only possible when long-term research is conducted.

• 한국문헌정보학회지
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• 제58권1호
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• pp.351-371
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• 2024

문화체육관광부 1차 소속기관으로 격상된 국립장애인도서관이 현 단계 가장 주력해야 할 과제는 독립청사 확보와 함께 전국장애인서비스를 총괄·선도하기 위한 전제조건으로서의 국내외 장애인자료를 전략적으로 수집하는 것이다. 본 연구는 국립장애인 도서관의 독립청사 건립 준비 및 외연 확대를 위하여 수집할 자료의 기초목록을 제시하였다. 법적 제약과 현실적 한계로 인하여 국립장애인도서관이 장애인자료를 수집하기 위해서는 연차적으로 자료구입비를 투입하여 구입에 주력해야 하며, 교육·학술자료와 미소장 및 소급 장애인자료의 망라적 수집을 위한 전략 수립이 요구된다. 이에 본 연구는 국립장애인도서관의 현행 장서개발정책을 기반으로 장애인자료를 포괄적으로 수집하기 위한 기초연구를 수행하였다. 구체적으로 국가도서관 및 주요 대학도서관의 소장자료를 대상으로 장애인 및 장애 관련 자료의 발행 및 수집동향을 분석하고 국립장애인도서관이 앞으로 확보할 현행 및 소급자료의 규모, 실물자료 및 다운로드 혹은 아카이빙 대상 자료군을 설정하기 위한 기초목록을 구축하였다.