• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2003.05a
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• pp.20-20
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• 2003

용융아연도금은 내식성 아연코팅목적으로 산업체에서 광범위하게 사용되고 있다. 이 공정에서 아연의 배출성능이 나쁜 관계로 피처리물의 끝부분에 고드름이 생기거나 작은 구멍을 메우는 문제가 종종 발생한다. 본 연구에서는 용융아연욕에 Bi를 단독 첨가하거나 Bi와 AI을 함께 첨가하여 이 문제를 해결하였다. Bi의 첨가는 아연의 배출성능을 현저하게 증가시켰으며 0.1 wt.% Bi, 0.025~0.05 wt.% AI을 함유한 용융아연욕에서 가장 균일성이 좋은 코팅층을 얻을 수 있었다. 산업현장 적용시험 결과 아연의 수율을 향상시켰고 드로스의 형성량이 감소하였다.

• Journal of Welding and Joining
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• v.16 no.6
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• pp.77-85
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• 1998

Effects of non-cleaning and cleaning fluxes on the wetting properties and defects at flow soldered joints were investigated. Non-cleaning flux (R-type of 3.3% solid content) and cleaning flux (RMA-type of 15% solid content) were used. Wetting test was accomplished by wetting balance method with changing surface state of wetting specimen, CU. Sn-37%Pb solder was used for wetting test and flow soldering. As experimental results, the wetting time for vertical force from the surface tension being zero was mainly affected by surface state of the wetting specimen. Non-cleaning flux had a good wettability compared with cleaning flux. In case of non-cleaning flux, conveyor speed had a great affection to defects of bridge, icicle, and poor solder.

• Journal of Science Education
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• v.38 no.1
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• pp.41-56
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• 2014

This study has developed STEAM educational program designed to cultivate topophilia using Jeonbuk educational resources and applied the program to a science camp. Topophilia is a sense of attachment and nostalgia towards one's birth place and specific objects, which can create positive affection and act as motivations for learning to the students. We developed a 32-hour STEAM program which consisted of 8 experiential activities and 2 travel programs including Gochujang, Hanok Village, a reverse ice spikes in Mai Mountain, and art works by Choi Book. In particular, we emphasized the fun of class, voluntary learning, and process of attaching significance by providing aesthetic and emotional experience of synesthesia. As a result of application, the students' level of confidence(Likert scale level 4, 2.5 points) in science and the level of interests(3.3 points) have improved. The pleasant experience of voluntary learning and active participation in class provided meaningful memories through value recognition and significance ascription. 93.3% of the students participated said they would recommend the Topophilia science camp to their peers. The level of satisfaction overall was 3.8 points(Likert scale level 5) and the program received positive evaluations that the class was fun and interesting(4.1 points).