• Corrosion Science and Technology
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• 제13권4호
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• pp.125-129
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• 2014

Shinning spot defects on galvanized steel sheets were studied by optical microscope, scanning electron microscope(SEM), Energy Dispersive Spectrometer (EDS) and Laser-Induced Breakdown Spectroscopy Original Position Statistic Distribution Analysis (LIBSOPA) in this study. The research shows that the coating thickness of shinning spot defects which caused by the substrate defect is much lower than normal area, and when skin passed, the shinning spot defect area can not touch with skin pass roll which result in the surface of shinning spot is flat while normal area is rough. The different coating morphologies have different effects on the reflection of light, which cause the shinning spot defects more brighter than normal area.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1300-1305
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• 2004

The purpose of this experiment is to study the radiant cooling effects by a plate directly viewing the nighttime sky. The measurements are performed at a rooftop of the Engineering building at the Dongguk University in Seoul during the month of August in 2004. The radiant cooling effects are compared using three different types of plate surfaces such as galvanized Iron, black painted, and aluminum film coated galvanized iron plate. Among these plates, the black painted surface show the lowest temperature that is lower than its ambient temperature. The maximum radiant cooling temperature difference, that is ambient temperature minus plate temperature, observed is about 5K..

• 한국표면공학회지
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• 제32권1호
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• pp.21-30
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• 1999

Coating adherance behavior of low carbon steels, produced by POSCO, Korea, was studied in order to study the characteristics of hot rolled galvanized iron(HGI) manufactured without pickling line and the development of its process. Galvanizing experiments were carried out in zinc pot with 0.2wt% Al after hot rolled plates with scale were reduced at $550~750^{\circ}C$ in 10~30% hydrogen gas atmosphere during 60~400seconds. The reduced plates and coated products were examined by SST, XRD, SEM and EPMA on their surfaces and cross sections. Coating layer of HGI manufactured with pickling line was composed of retained scale, Fe-Zn-Al compound, Fe-Zn compound ($\delta_1\;and\;\zeta$ Phase) and pure zinc. It was superior to HGI in coating adhesion. It seems to be due to forming of Fe-Zn-Al compound in interface of matrix and retained porous scale.

• 한국표면공학회지
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• 제32권1호
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• pp.31-42
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• 1999

The effect was investigated that aluminium in the zinc bath has on the coating adhesion of Hot-rolled Galvanized Iron(HGI) manufactured without pickling process. It is thought that the coating adhesion of HGI manufactured without pickling process is good due to the fact that increasing aluminium content in the zinc bath makes zinc and aluminium diffuse to the cracks or pores in the scale formed through the reduction heat treatment, and Fe-Zn-Al compound with good ductility is formed in the scale layer and plays a role of anchor between zinc coating and substrate. It is possible that HGI with the good coating adhesion was produced without pickling treatment in the zinc bath with more that 3wt% of Al content even at the $550^{\circ}C$ of conventional reduction heating temperature. In creasing the temperature of heating section and aluminium content in the zinc bath prevents the Zn-Fe alloy. The corrosion resistance of HGI manufactured without pickling process is excellent because of the mixed reaction of zinc sacrifice and aluminium passivity film.

• 설비공학논문집
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• 제17권6호
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• pp.605-610
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• 2005

The purpose of this experiment is to study the radiant cooling effects by a plate directly viewing the nighttime sky. The measurements are performed on a rooftop of the Engineering building at the Dongguk University in Seoul during the month of August in 2004. The radiant cooling effects are compared using three different types of plate sufaces, namely, galvanized iron, black painted, and aluminum film coated galvanized iron plate. Among these plates, the black Painted surface showed the lowest temperature that is lower than the ambient temperature. The maximum radiant cooling temperature difference, which is ambient temperature minus plate temperature, observed is about 5 K.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 1998년도 춘계학술발표회 초록집
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• pp.69-69
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• 1998

• 한국환경과학회지
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• 제16권1호
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• pp.121-128
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• 2007

This study performed in order to evaluate the effects of pipe materials on corrosion and bacteria regrowth using a laboratory scale batch test. Two varieties of feed water with different microbial conditions were selected: tap water, surface river water (Han River water), and five pipe materials; carbon steel, copper, galvanized iron, stainless steel, and PVC, Carbon steel and galvanized iron pipes showed higher corrosion rates than other materials. In terms of attached bacterial growth, pipes with PVC and stainless steel showed higher bacteria concentration compared to other materials. Pseudomonas vesicularis was the predominant bacteria found on biofilm. The behavior of bacterial growth in the pipes was observed using a scanning electron microscope.

• 한국표면공학회지
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• 제31권6호
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• pp.379-388
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• 1998

The iron-zinc interfacial reaction and corrosin properties in galvanizing bath containning Ni have been intestigated. The substrate steel plates were galvanized in Zn or Zn-0.018Al baths with various Ni contents. The corrosion resistance of galvanized specimens was also evaluated by $60^{\circ}$bending test for galvannealing speaaimens. The corrosion resistance was improved with Ni addition in pure Zn bath, while deteriorated with Ni addition in Zn-0.18Al bath. The anti-powdering property, on thhe otherhand, was improved with Ni addition in Zn-0.18Al bath, while deteriorated with Ni addition in pure Zn. It was found that the anti-powdering property was improved with increasing $\xi$ phase ratio in reaction layer.

• 한국표면공학회지
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• 제36권6호
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• pp.466-474
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• 2003

To develop a method of detecting dross in coating layer on hot-dip galvanizing steel, chemical etching behavior of the artificial coating layers with top and bottom dross were investigated. After chemical etching with the mixture of picric acid and sodium thiosulfate, each of the top and bottom dross take its distinct color, and alloy layer in coating is also observed. Defects in the coating layers of HGI(hot rolled galvanized iron), CGI(continuous galvanized steel sheet) and GA(galvannealed steel) were analysed, and methods of dross detection which can be applied to inspection process in manufacture were suggested.

• 대한지리학회지
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• 제51권3호
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• pp.441-454
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• 2016

이 연구는 지붕 형태, 지붕 재료, 외벽 재료에 초점을 두고 울릉도 산지 촌락 가옥의 유형과 특성을 고찰하는 연구이다. 그리고 울릉도 산지의 촌락 가옥 유형을 제주도와 경남의 촌락 가옥 유형과 비교하면서 그 특성도 논의한다. 울릉도 산지 촌락 가옥의 지붕 형태를 보면, 팔작지붕(42.1%)이 가장 많이 나타나고, 그 다음으로는 맞배지붕(25.8%), 우진각지붕(11.8%), 단순평지붕(10.7%) 등이 많이 나타난다. 지붕 재료를 보면, 컬러강판(69.1%), 아스팔트싱글(11.8%), 시멘트(10.7%) 등이 많이 나타난다. 컬러강판을 지붕 재료로 사용한 가옥이 압도적으로 많고, 기와나 슬레이트를 지붕 재료로 사용한 가옥은 한 채도 없다. 그리고 외벽 재료에서는 시멘트(27.5%), 사이딩(21.3%), 함석(16.8%), 목재(6.7%) 등이 많이 나타난다. 지붕 형태와 지붕 재료의 결합 관계로 본 가옥 유형에서는 팔작지붕-컬러강판 가옥 유형(73채; 41.0%)이 가장 많이 나타나고, 지붕 형태를 중심으로 해서 지붕 재료와 외벽 재료의 결합 관계로 본 가옥 유형에서는 팔작지붕-컬러강판-시멘트 가옥 유형(32채; 18.0%)이 가장 많이 나타난다. 울릉도 산지 촌락 가옥의 지붕/외벽 재료로 함석을 사용하는 빈도가 높은 것, 기와나 슬레이트를 지붕 재료로 사용하지 않는 것, 적벽돌이나 석재를 외벽 재료로 사용하는 빈도가 낮은 것 등은 건축 자재의 운송비용과 관련이 있을 것이다.