• International Journal of Highway Engineering
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• v.20 no.4
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• pp.35-46
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• 2018

PURPOSES : The purpose of this study is to compare the lane curing time of natural drying and a lane drying device when painting lines on a highway. METHODS : The painting process was carried out in July 2015 and September 2015, respectively, for the Gimcheon IC - Gimcheon JC. After the painting, measurements were obtained three times at six measurement points located at 20 m intervals on the shoulder line and the dividing line. The curing time was measured for natural drying and drying using a lane drying device, and compared for different pavement types (asphalt, concrete) and paint types (waterborne paint, methyl methacrylate paint). RESULTS : The results of the lane curing time comparison on the highway are as follows. The combination of asphalt and methyl methacrylate paint cured more rapidly during both the natural drying and drying using the lane drying device. Finally, it was cured at least 32.2% and 40.7% faster when using a drying device than in natural drying. CONCLUSIONS : The comparison of lane curing time of the highway showed that the combination of asphalt and methyl methacrylate paint cured more rapidly when using both natural drying and a lane drying device.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.12
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• pp.828-836
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• 2010

The drying is a process that involves coupled and simultaneous heat and mass transfer. When a wet solid is subjected to thermal drying, two processes occur simultaneously. Drying is classified according to heat transfer characteristics in terms of conduction, convection and radiation. In thermal drying, radiation is easier to control than conduction and convection drying and involves a relatively simple structure. In this study, we measured energy consumption, surface hardness of paint and surface gloss with variation of surface temperature of drying materials and drying time. Drying characteristics and energy consumption between heating panels and hot air heating have been presented. The present study shows that a dryer using heating panels is more effective than a hot air dryer from the viewpoint of energy conservation. The hot air dryer, however, was not optimized and more studies on various parameters related to drying will need to be investigated for definite comparison of drying characteristics of the dryers. The result, even if limited, would present the effective availability of paint drying.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.12
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• pp.867-874
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• 2012

In the present study, three-dimensional transient numerical simulations were carried out to improve the performance of a vehicle paint drying process. In order to describe the movement of a vehicle, the techniques of moving boundary condition and multiple reference flames (MRF) were used. For the validation of the numerical analysis, the predicted temperature on the surface of a vehicle was compared to the experimental data, and a good agreement was achieved. With validated numerical procedure, various operating conditions of the temperature and the flow rate of the supply air were investigated to improve the drying performance of the facility. It is shown that the optimization of the operating condition can lead to energy savings and faster line speed of the production.

• Journal of the Korea Institute of Building Construction
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• v.3 no.1
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• pp.107-114
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• 2003

This study aims to find methods that prevents aging of buildings paint coating and that limits defects in construction. Defects in painting can occur in four stages: pure paint, during painting, after the paint coating has dried, and after some period of time has passed after coating. Paint may become bad due to precipitation of pigments, formation of membranes, and seeding during manufacturing. Therefore, it is important that the paint is well mixed and kept airtight at a cool, dark place. Indents, paint brush strokes, orange peel, separation of colors, and paint running and spreading during the paint work process can be prevented by using high quality materials and applying a high-level of construction method. After the paint coating has dried, boiling, yellowing, poor drying, poor bonding, and/or glen deficiency may occur. These are influenced by the levels of cleanness of the dried product, drying temperature and hydration. Then, when the coating has been left dried for some period of time, cracking, peeling, scaling, swelling, discoloring, and/or rusting may develop due to the ultraviolet and contaminants in the air. Since these defects occur due to inappropriate construction schedule and/or hot and humid condition, one must use weatherproof materials. Furthermore, poor paint color may be caused by contamination in the sample plate, discoloration, and/or discrepancies in colors which are due to material differences, level of glossiness, degree of dispersion, dual color property of metallic colors, precipitation of pigments, etc. One should achieve reduction in construction cost and effectiveness in paint work by limiting contaminations in the construction site and strictly observing to construction regulations.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.97-101
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• 2001

Composite materials have been applied widely in interior panels of buildings and transport vehicles. Recently good fire performance and weight reduction are key issues in the fields. In the present study we investigated effects of processing parameters on the performance of honeycomb sandwich panels, especially peel strength of the panel and fire performance. The processing parameters considered were types of matrix resin, resin contents, panel cure conditions, and surface painting process conditions. The results showed that the higher resin content provides the better peel strength. Controled cure steps are also needed to obtain good pee] strength. Paint processing parameters including base putty thickness and paint drying conditions and paint thickness are important to obtain good paint adhesion and good fire performance.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.18 no.4
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• pp.293-302
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• 2008

Lead chromate is made by sodium dichromate and lead acetate, and has being used widely in the part of pigment, paints, inks, plastics and so on. Even though lead chromate has health hazards which like both lead and chromium, there are a few study about pigment workplaces using lead chromate in Korea. The purpose of this study is to evaluate workers' exposure levels and airborne lead and chromium concentration in the pigment workplaces using lead chromate. There are 20 workers in the total 5 workplaces. 10 workers(50%) have been exposed to lead and 3 workers(15%) have been exposed to chromium, which exceeded the American Conference of Governmental Industrial Hygienists(ACGIH) Threshold Limit Value (Pb: $0.05\;mg/m^3$, Cr: $0.012\;mg/m^3$) and Korean Ministry of Labor's Standard. Geometric mean (GM) of airborne lead was highest in pigment ($0.0421\;mg/m^3$), paint ($0.0020\;mg/m^3$) and PVC coloring ($0.0007\;mg/m^3$), respectively(p<0.05). The result of airborne chromium concentration was paint ($0.0033\;mg/m^3$), paint ($0.0004\;mg/m^3$) and PVC coloring ($0.0003\;mg/m^3$). Also the lead and chromium concentration in the manual process is each 30 times and 10 times higher than the value in automatic process(p<0.01). In the classified process by detail, the concentration of airborne lead was $0.0638\;mg/m^3$ in grinding & packaging, mixture & after-measuring ($0.0436\;mg/m^3$), filtration & drying ($0.0402\;mg/m^3$), lead nitrate & dissolution($0.0129\;mg/m^3$), pigment commitment & mixture ($0.0013\;mg/m^3$) and dispersion & grinding ($0.0010\;mg/m^3$) (p<0.05). Moreover the concentration of a sample in weighting & packaging was $0.0023\;mg/m^3$. The concentration of lead in workers' blood was pigment (15.12 ug/dl), paint (4.74 ug/dl) and PVC coloring (2.50 ug/dl), and some samples have exceeded biological exposure limit. In conclusion, the depending on their work industry and process, workers have been exposed to the high lead chromate.

• Journal of architectural history
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• v.31 no.4
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• pp.45-56
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• 2022

Gachiljang(假漆匠), along with Jinchiljang(眞漆匠), is an important craftsman who cannot be left out during the finishing process of wooden furniture and wooden buildings during the Joseon Dynasty. The current definition of Gachiljang does not properly explain the nature and role of Gachiljang. In many related terminology dictionaries, Gachiljang is defined as "artisan who dose the base paintwork of Dancheong." But an analysis of the Joseon Dynasty's Uigwe(儀軌) shows that Gachiljang appears frequently in works that are not related to Dancheong at all. Therefore the current definition seems to be inaccurate and need to be revised. Gachiljang is a name that contrasts with Jinchiljang, and he makes and paints Myongyu(明油). Just as Jinchiljang uses not only lacquer but also various pigments to paint colorful lacquer, Gachiljang also uses various pigments to decorate buildings or furniture in a fancy way and then finishs with a transparent paint. Even in the Dancheong(丹靑) work of the building, all the base painting and finish coating work will be in charge of Gachiljang, except for the paintings performed by the Whawon(畫員) or the Whasa(畫師).

• Korean Journal of Materials Research
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• v.22 no.10
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• pp.531-538
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• 2012

Hollow silica spheres were prepared by spray drying of precursor solution of colloidal silica. The precursor solution is composed of 10-20 nm colloidal silica dispersed in a water or ethanol-water mixture solvent with additives of tris hydroxymethyl aminomethane. The effect of pH and concentrations of the precursor and additives on the formation of hollow sphere particles was studied. The spray drying process parameters of the precursor feeding rate, inlet temperature, and gas flow rate are controlled to produce the hollow spherical silica. The mixed solvent of ethanol and water was preferred because it improved the hollowness of the spheres better than plain water did. It was possible to obtain hollow silica from high concentration of 14.3 wt% silica precursor with pH 3. The thermal conductivity and total solar reflectivity of the hollow silica sample was measured and compared with those values of other commercial insulating fillers of glass beads and $TiO_2$ for applications of insulating paint, in which the glass beads are representative of the low thermal conductive fillers and the $TiO_2$ is representative of infrared reflective fillers. The thermal conductivity of hollow silica was comparable to that of the glass beads and the total solar reflectivity was higher than that of $TiO_2$.