• 한국초등과학교육학회지:초등과학교육
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• 제24권4호
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• pp.443-451
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• 2005

This study was designed to investigate children's response types, which are always consistent when they meet with different evidence materials. The participants in this study were 119 students of 6th grade in elementary school, who were acquainted with evidence materials presented and able to state logically. Evidence materials were constructed on the main subjects of a cause of the dinosaur extermination and a purpose of the astronomical observatory establishment. The criteria, 'whether or not believe evidence materials presented', 'whether or not believe evidence materials newly presented', 'where or not decrease their belief in the preinstructional evidence materials', and 'whether or not change their belief' were used to classify the type of their responses. So the students' responses to the evidence materials were classified into low types: rejection, reinterpretation, belief decrease, and valuation by evidences. Only about a third of them was also consistent with response types, but the others showed individually different responses to new evidence materials. The types of belief decrease and valuation by evidences were relatively below, while those of the rejection and reinterpretation were likely to represent them again, and these results did not reflect a meaningful difference between male and female. These results show that children's response type are not always coherent, and that they respond variously according to the evidence materials except for an individual cognitive view and a background in estimating evidence materials, and most of them are contents dependent in evaluating evidences. Therefore we are expected to apply it to studies on a thought process of the student as data on the basis of them and develop more various evidence materials responded by basis on evidence.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2011년도 춘계학술논문집 2부
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• pp.679-682
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• 2011

The effects of heat input(1.5~3.6kJ/mm) and postweld heat treatment(PWHT, $600^{\circ}C$, 40hr.) on the TMCP HSB600 steel weldments made by GMAW process were investigated. The tensile strength and CVN impact energy of as-welded specimens decreased with increasing heat input. The fine-grained acicular ferrite was mainly formed in the low heat input while polygonal and side plate ferrites were dominated in the high inputs. Meanwhile, tensile strength and hardness of PWHT weldments decreased due to the coarsening of microstructure and reduction of residual stresses.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2011년도 추계학술논문집 2부
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• pp.391-393
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• 2011

본 연구에서는 원자력 발전 및 화력 발전소에서 Turbine 운전 시 열교환기 및 콘덴서에 증기를 응축시 열효율을 높여주기 위해 콘덴서 Tube 내에 이물질 및 스케일을 Sponge Ball을 이용하여 자동으로 제거하는 장치로서 콘덴서 튜브 클리닝 시스템(CTCS)에 사용되고 있는 Screen 재료인 Duplex Stainless Steel UNS S31803의 파손사례에 대해 연구하였다. 파손원인 분석은 스크린의 강도해석, 재료의 화학분석시험, 조직시험 및 점용접부의 신뢰성 시험(Peel-off test)으로 수행되었고 저항용접부의 용접 불량 때문에 발생하였을 확인하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1378-1381
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• 2006

The CNTs are the most extensively studied material which are characterized by the complete property of matter, structure, and the large thermal conductivity (Thermal conductivity of $CNTs\;{\sim}>2000W/mK$ vs. Thermal conductivity of Aluminum ${\sim}\;>204W/mK$). Thus, they are successfully applied to the various fields. However, due to the strong agglomeration caused by the van der waal's force, their applications are limited. In the present study, a new method for CNTs dispersion was developed by using the mechanical dispersion, acid treatment, and then Cu was coated. This process produces CNTs/Cu nanocomposite powders, whereby the CNTs are homogeneously located within the Cu powders. The thermal properties of the CNTs/Cu nanocomposite were investigated.

• Elastomers and Composites
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• 제52권1호
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• pp.17-21
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• 2017

The optimum mixing conditions of silica and silane containing rubber composites were evaluated by investigating the properties of rubber composites prepared with a silica composition of 10, 20, 40, 60, and 80 g, respectively. The crosslinking rate decreased with increasing silica content, with he promoters being adsorbed on the silica surface with in the rubber composite. As a result, the increase in crosslinking time resulted in the destruction of the silica structure. The increase of the bound rubber content due to the destruction of the silica structure inhibited the chain motion of the polymer molecules and reduced the cohesion of the silica itself. Finally, the increase of silica content showed the increase of hardness, tensile strength, and storage modulus of rubber composites.

• 한국표면공학회지
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• 제38권2호
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• pp.55-59
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• 2005

ITO/Ni/ITO thin films were deposited on the PET by RF magnetron sputtering. Dependance of the process parameters such as deposition pressure, positions of Ni layer, on the transmittance, reflectance and sheet resistance of ITO/Ni/ITO film were investigated. When the Ni layer is placed at the center of ITO and deposition pressure is low, ITO/Ni/ITO films showed better optical and electrical properties. At these conditions, the transmittance, reflectance and sheet resistance of the ITO film were $90\%,\;0.38\%$ and $185\Omega/\Box$ respectively.

• 한국어교육
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• 제23권1호
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• pp.25-45
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• 2012

The purpose of this article is to examine types and construction method of multimedia materials for the Korean language education, finally in order to construct digital library on Nuri-Sejonghakdang. Firstly, this article reviews some major concepts such as teaching material, multimedia, learning object, meta-data, reusability, etc. Secondly, various multimedia materials are divided into three types(namely, example material, explanation material, training and evaluating material) according to their characteristics as a learning objects. And then, this article tries to propose the classification-search system and meta-data elements for effective search and use of multimedia materials. Finally, this article is concluded by presenting the long-term plan of digital library construction on Nuri-Sejonghakdang and some follow-up task of this study.

• 한국과학교육학회지
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• 제11권1호
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• pp.117-126
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• 1991

The new movement in science education in America and Europe has been heavilly oriented into technological and soceital aspect of science since 1970. However, this spirit has not been well informed in Korea and not adapted in science education. This paper aimed to arouse Korean science educators attention to everyday situation as a science education context. In this paper, the discipline centered science education was briefly reviewed and problems related to the philosophy was pointed out. At the same time the researcher introduced STS context as a science education objective, and elaborated the three elements(physical situation, technological situation. and societal situation) of the context. In the paper, the advantages of the use of everyday context in science education were examined. THe advantages were analysed in terms of the nature of science, learning psychology, integrated science, and societal aspect of science education. The paper also suggested the criteria to select teaching materials from STS context. The suggested criteria were the degree of science concepts involvement, frequency of experience, strength of experience, and possibility of direct experience.

• 한국전자파학회논문지
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• 제12권1호
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• pp.27-36
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• 2001

In this paper, micromachined millimeter-wave cavity resonators ar presented. One-port and two-port cavity resonators at Ka-band are designed using 3D design software, HP $HFSS^{TM}$ ver. 5.5 Cavity resonators are fabricated on Si substrate, which is etched down for the cavity, bonded with a Quartz wafer in which metal patterns for the feeding line coupling slot are formed. One-port resonator shows the resonant frequency of 39.34 GHz, the return loss of 14.5 dB, and the loaded $Q(Q_{L})$ of 150. Two-port cavity resonator shows the resonant frequency of 39 GHz, the insertion and return losses of 4.6dB and 19,9dB, the loaded($Q_{L}$) and unloaded $Q(Q_{U})$) of 44.3 and 107, respectively.

• 정보교육학회논문지
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• 제22권4호
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• pp.473-489
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• 2018

컴퓨터 정보 리터러시는 21C를 살아가는 학생들에게 길러주어야 할 주요 핵심 역량 중 하나이다. 미국, 영국 등 세계 여러 나라는 학생들의 컴퓨터 정보 리터러시를 신장시키기 위하여 소프트웨어 교육 내용을 교육과정에 포함시키고 있다. 우리나라도 2015 개정 교육과정에서 소프트웨어 교육을 강조하였다. 위와 같은 교육적 변화에 대처하기 위해 많은 책자 형태의 소프트웨어 교육 교재들이 개발되고 있다. 하지만 이러한 교재들이 컴퓨터 정보 리터러시를 신장시키기에 적합한지 알아보는 연구는 아직 미흡하다. 본 연구에서는 국가 기관의 주도로 온라인 상에 보급된 네 권의 소프트웨어 교육 교재가 컴퓨터 정보 리터러시를 신장시키기에 적합한 지 평가하였다. 연구의 대상은 초등학생에게 피지컬 컴퓨팅을 지도하기 위한 교재로 한정하였다. 우선, 교육부에서 제공한 '검 인정 교과서 평가 기준'과 '2018 ICILS 평가 틀'을 참고하여 교재 평가 기준을 개발하였다. 다음으로 소프트웨어 교육에 전문성을 갖춘 12명의 현장 교사를 선정하였고, 개발된 평가 틀을 이용하여 교재 평가를 실시하였다. 평가가 끝난 후, 평가 위원들이 매긴 점수를 평균 내어 3.5 이상을 우수한 교재로, 3.5 미만은 미흡한 교재로 구분하였다. 그리고 우수한 교재의 특징과 미흡한 교재의 특징을 추출하였다. 마지막으로 연구의 결과를 바탕으로 컴퓨터 정보 리터러시를 길러 줄 수 있는 피지컬 컴퓨팅 교육 교재 개발을 위한 시사점을 제시하였다.