• Proceedings of the KWS Conference
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• 2000.10a
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• pp.268-270
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• 2000

• Proceedings of the KWS Conference
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• 1997.10a
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• pp.43-45
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• 1997

• Proceedings of the KWS Conference
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• 2001.05a
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• pp.171-173
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• 2001

• Journal of Korean Society of Steel Construction
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• v.23 no.3
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• pp.295-304
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• 2011

Bracket-type connection is often used for the weak-axis steel connection. In general, a beam-to-column connection for the bracket type is fabricated at the shop and abeam splice is additionally attached to the bracket in the site. Therefore, steel construction would not be competitive due to the increase of beam splice fabrication cost and overall construction period. This paper now proposes the new weak-axis connection types without a scallop, which has more definite strength flow, simple connection details, and better workability. From the series of experiments, the proposed connections showed better strength and ductility in comparison with standard details with scallop because the thickness of the welding plate for wide-flanged, beam-to-column connection can be easily adjusted.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.8 no.2
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• pp.76-82
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• 2009

In this papers, Study on the Bonding property and Strength Evaluation in Bonding interface Joints of Dissimilar material using DOE. We found optimal condition that uses experimental design method (Response Surface Analysis, DOE) used temperature, pressure, time on experiment factor. And we could get bonding condition and strength that break and crack do not happen in mechanical processing about united dissimilar material. And progress 3 point bending tests and verified result.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.186-186
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• 2013

반도체 배선용 무전해 구리 도금에서 pH조정제가 구리피막과 Ta 확산방지막 사이의 접합력에 미치는 영향에 대하여 연구하였다. TMAH로 pH가 조절된 경우 NaOH 사용시에 비하여 높은 접합력을 나타내었다. 면간거리 및 밀도 측정결과 TMAH를 사용한 경우 구리피막이 보다 치밀한 구조임을 확인할 수 있었다. TMAH 사용시의 높은 접합력은 NaOH을 사용 한 경우에 비하여 무전해 구리피막이 보다 낮은 내부응력을 갖기 때문으로 판단되었다. pH조정제에 따른 내부응력의 변화를 결정구조의 관점에서 자세히 고찰하였다.

• Korean Journal of Materials Research
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• v.6 no.11
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• pp.1146-1152
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• 1996

실제 사용시 신뢰성을 보장하기 위하여, 고온에서 장시간 동안의 시효로 인한 ACA COG(Anisotropic Conductive Chip On Glass) 접합 특성의 변화가 연구되었다. 모든 접합 시편들은 16$0^{\circ}C$에서 156시간 동안 유지되었고 시효하는 동안의 접촉저항의 변화는 감소하였다. 특히, 156시간이후, 4000개 /$\textrm{mm}^2$의 입자밀도를 가진 ACA에서는 접촉저항의 벼노하가 나타나지 않았다. 입자크기의 경우 작은 입자를 가진 ACA는 16$0^{\circ}C$에서 시효후에도 접촉저항의 변화를 보이지 않았다. 또한 4000개/$\textrm{mm}^2$ 및 5$\mu\textrm{m}$ 입자를 가진 ACA를 사용한 시편은 접합상태가 안정하였기 때문에 16$0^{\circ}C$에서도 경화수지의 팽창 및 리플로우(reflow)에 의한 영향을 받지 않았다. 따라서 이 ACA에서는 16$0^{\circ}C$에서 156시간 동안 시효한 후에도 오픈(open)이 나타나지 않았다.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.123-128
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• 2018

Effect of activators in flux on the printability and wettability of a solder paste was evaluated in this study. The activators in this study were dicarboxylic acids, which were oxalic acid (n = 0), malonic acid (n = 1), succinic acid (n = 2), glutaric acid (n = 3), adipic acid (n = 4), and pimelic acid (n = 5). When the solder pastes were observed with a SMT scope, solder with glutaric acid showed clean and shiny surface when it was melted. Slump ratio of the solder pastes was low when the carbon numbers of the dicarboxylic acid were 1-3. Spreadability was high when the carbon number was over 2. Zero cross time of wetting balance test was under 1 sec when the carbon number was over 3. When activator was oxalic acid or malonic acid, zero cross time was over 1 sec and maximum wetting force was low. Fluxes with the oxalic acid and malonic acid showed decomposition at the temperature close to melting point. Among the dicarboxylic acids, glutaric acid provided excellent slump, spreadability, and wettability.

• Conservation Science in Museum
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• v.7
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• pp.3-10
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• 2006

The bronze bowl with lid excavated from Eunnyeongchong Tumulus in Gyeongju had been united in the past and then damaged. We removed deteriorated adhesive and other impurities from it and reunited it. Some fragments of the artifact has been lost; in particular, only half of the whole main body remains. Therefore, it needed restoration treatment for exhibition and conservation. The lid, relatively much part of which remains, was treated with the method that could easily detach the restored part; the main body with much restored part was united using epoxy resin so that the restored part could well bear the weight of the artifact.

• Proceedings of the KWS Conference
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• 2008.05a
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• pp.25-25
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• 2008