• 한국기계가공학회지
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• 제5권4호
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• pp.33-40
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• 2006

The quality of the supply water which is supplied to consumer is not the thing of water after filtrating but the thing of water from faucet through pipe. As a result, heavy metals and microorganism, that is the major materials, which cause the distrust of the supply water is generated by supply process. Especially, the heavy metal is generated by the corrosion of waterworks. Besides, rupture by corrosion of pipe becomes the factor of supply water's pollution in waterworks and the factor of pollution of the soil and environment in drain pipe. Therefore, this research examined the weight reduction electric potential measure to measure the corrosion degree of piping materials after testing the corrosion of piping materials(Copper Pipe, Galvanized Steel Pipe, Stainless Steel Pipe) which is generally used at the moment in various corrosion environments(subterranean water, supply water, 3.5% NaCl, 3.5% $HNO_3$). And let me show basic design data about problem occurrence such as leakage water, rust water, inside and outside corrosion from this.

• Design & Manufacturing
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• 제11권2호
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• pp.15-19
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• 2017

Carbon fiber reinforced plastic (CFRP) is applied as structural material. CFRP is excellent in plane strength / stiffness and don't haves rust. Lightweight, rigid and robust at the same time as transportation material. Aluminum alloy and reinforcement material The application is increasing rapidly. In this study, the prototype of a semi - Monocoque structure frame, Longeron, Stringer, Skin of the aircraft, restraining the rigidity Clips of the aircraft was designated as the target product and the experiment was conducted. ln the experiment, (1) For CFRTP 3 points, data on heating, transfer, and cooling were measured using Thermo Couple, and optimum temperature required for flexible state was obtained. Heating was performed at a temperature 15% higher than the provided temperature. (2) By using a pneumatic press during molding, by dividing LH, center and RH according to the cooling time, thickness parameter of the target product due to the load is measured, and thickness control and time-deviations were analyzed and cross sections were observed with a low magnification microscope.

• 한국실내디자인학회논문집
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• 제32호
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• pp.82-89
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• 2002

This study is focused on the chairs for students, especially, middle school students who grow rapidly compared with other group. We make a certain definite possibilities by the scientific and medical comparison of the approved chair with existing chair about the function of feet-height control & the application of the flexible back. The object of this test is middle & high school student (ratio of gender is the same) in Inchon. And the study types are two. One is to bring a matter and to suggest a design as alternative, the other is to verify propriety of the alternative. The major finding from the research are summarized as follows: 1) K·S standards for existing chairs are not proper to the growth rate of present juveniles, and they don't cope with proactive the discrepancy of growth pace. 2) Existing chairs have caused troubles by using only the fixed back of a chair. This troubles made bad influences on juveniles in a growth period. 3) Even existing chairs can adjust the back of a chair, they can be easily broken , and if they adjusted once, they can't be easily controled. Furthermore, it is Impossible to manage them because of the rust of control parts. 4) In the case of supplying the same sizes of them, juveniles who are different to growth rate respectively, can't accept the chairs. Even supplied adjustable chairs, they cant be ideal types of chairs in Open Classroom mode.

• 보존과학연구
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• 통권19호
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• pp.109-132
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• 1998

According to excavation of Imdang site, these sites were excavated place to a various of sites from Early lron period to the Koryo Kingdom. Artifacts to be conserved were excavated from A, D and E district. Metal artifacts were excavated from D and E district and lacquer ware artifacts were excavated from Adistrict. Metal artifacts including lacquer ware iron sword, imitative bronze mirror, Osujen and bronze artifact with letter and so on. Bronze artifacts were covered with soil and rust and performed consolidation after passivation treatment with Benzotriazole solution. Also, iron artifacts performed desalting treatment with 0.1M sesquicarbonate solution. After desalinization, adhesive of these artifacts were processed with Araldite(rapid type) after consolidation with20%∼30% NAD-10 solution. Lacquer ware artifacts remained fragments of lacquer to be all corroded and soiled. Therefore these artifacts retained its original form. Fragments of lacquer joined with Caparol 1%∼3% solution and the soil of relics coated with PSNY 3%∼6% solution. There were many kinds of lacquer were. Lacquer ware artifacts presumed to a string instrument that provide important clues for lacquer ware research. As for lacquer fragments inquire, paints grain size were $2∼5\mum$ and conformed to vanished three times.

• 박물관보존과학
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• 제14권
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• pp.1-5
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• 2013

공주박물관에서 의뢰한 공주 수촌리 출토 봉상의 칠기 칼집을 보존처리 및 분석을 하였다. 이 칠기는 철제유물들과 일괄 수습되었다. 전체적으로 외압에 의해 파손되어 있었으며 일부 칠기 편은 철 산화물에 부착되어 있고 손실된 부분도 있었다. 먼저 X-ray 촬영을 통해 함께 출토된 금속구와의 관계를 파악하고 칠 도막에 대한 분석을 하여 제작기법에 대해 연구하였다. 그 후 보존처리를 하여 원래의 형태를 구현하고자 하였으며, 보관 및 전시를 위한 보호틀을 제작하였다.

• 대한조선학회논문집
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• 제47권5호
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• pp.743-749
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• 2010

Multi-nozzle spray painting procedure of the inorganic zinc shop primer was established in order to obtain uniform film thickness. The shop primer paint prevents the corrosion of steel block during shipbuilding. When the dry film thickness of shop primer is insufficient, rust will be generated on the steel block. Otherwise, thick coating of shop primer may be a problem of weld defect. So, it is important to obtain the uniform film thickness of shop primer. The uniformity of dry film thickness is affected by spray speed, distance from spray gun to target surface and overlapping span of spray path. In order to uniformly maintain coating thickness of shop primer, the coating procedure was established based on the correlation of shop primer spray variables.

• 한국산업융합학회 논문집
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• 제24권5호
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• pp.581-587
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• 2021

In recent years, contamination of drinking water sources has emerged as a serious social problem, such as a large number of impurities in tap water or groundwater or the supply of suitable water due to rust of pipes. Although the government and public institutions are implementing various measures to protect water sources, they cannot improve water quality in a short period of time because of the enormous cost involved. Therefore, in recent years, preference has been given to a device that converts tap water, which is hard water, into soft water by installing a separate water softener at the faucet from which tap water is discharged. However, the existing filtration device has a problem that filtration performance is gradually lowered when impurities accumulate in the filter, requiring continuous filter replacement. In this study, the optimal design of the filter housing was performed to develop a water softener that can be washed when impurities accumulate on the filter inside the water softener connected to the faucet. For optimal design of the filter housing, fluid and fluid-structural interaction analysis were performed on the design pressure to determine the shape and thickness of the housing, and design review was performed through prototype.

• 한국표면공학회지
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• 제54권5호
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• pp.278-284
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• 2021

Corrosion of steel plate is common phenomenon which results in the gradual destruction caused by a wide variety of environments. Corrosion monitoring is the tracking of the degradation progress for a long period of time. Corrosion on steel plate appears as a discoloration and any irregularities on the surface. In this study, we developed a quantitative evaluation method of the rust formed on steel plate by using k-means clustering from the corroded area in a given image. The k-means clustering for automated corrosion detection was based on the GrabCut segmentation and Gaussian mixture model(GMM). Image color of the corroded surface at cut-edge area was analyzed quantitatively based on HSV(Hue, Saturation, Value) color space.

• Corrosion Science and Technology
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• 제18권4호
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• pp.121-128
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• 2019

Electrochemical Impedance Spectroscopy (EIS) was used to predict corrosion behaviour of metallic Cultural Heritage assets in two monitoring campaigns: 1) an iron bar chain exposed indoor from over 500 years in the Notre Dame Cathedral in Amiens (France); and 2) a large weathering steel sculpture exposed outdoor from tens of years in Ferrara (Italy). The EIS portable instrument employed was battery operated. In situ EIS measurements on the iron chain could be used to investigate the phenomena involved in the electrochemical interfaces among various corrosion products and assess and predict their corrosion behaviour in different areas of the Cathedral. Meanwhile, the sculpture of weathering steel, like most outdoor artefacts, showed rust layers of different chemical composition and colour depending on the orientation of metal plates. The EIS monitoring campaign was carried out on different areas of the artefact surface, allowing assessment of their protective effectiveness. Results of EIS measurements evidenced how employing a simple test that could be performed in situ without damaging the artefacts surface is possible to quickly gain knowledge of the conservation state of an artefact and highlight potential danger conditions.

• 국제강구조저널
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• 제18권5호
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• pp.1631-1638
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• 2018

In the periodic repainting of steel bridges, often the steel surface has to be prepared by using power tools to remove surface contaminants, such as deteriorated paint film and rust, and to increase the adhesive strengths of the paint films to be applied newly. Surface preparation by bristle roll-brush grinding, which is a type of power tool, may additionally introduce compressive residual stress and increase the fatigue resistance of welded joints owing to the impact of rotating bristle tips. In this study, fatigue tests were conducted for longitudinally out-of-plane gusset fillet welded joints and transversely butt-welded joints to evaluate the effect of bristle roll-brush grinding prior to repainting on the fatigue resistance of the welded joints. The test results showed that bristle roll-brush grinding introduced compressive residual stress and significantly increased fatigue limits by over 50%.