• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.2
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• pp.85-92
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• 2007

In 1980s, a number of bridges with bare concrete deck were constructed on the Korea highway. After 20 years service, many bare concrete decks are still in good condition without special maintenance activity. Therefore, the application of the bare concrete deck is being reestimated from the view of construction and maintenance. As a part of the program, the characteristic of penetration(surface chloride and apparent diffusion coefficient) of de-icing salt into bare concrete bridge deck was analyzed in order to predict the service life of bridge on Korea highway.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.4
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• pp.363-370
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• 2020

This paper reports the results of an experimental study using the BOTDR sensor to detect the unbonded location of attached CFRP sheet for structural rehabilitation. A specimens with the unattached CFRP sheet were fabricated for this study, on which BOTDR sensor was attached with a nylon net. During the flexural test of the specimens, the strain of the CFRP sheet was measured using the BOTDR sensor and electric resistance gauges. From the results, it was confirmed that the strain distribution obtained through the BOTDR sensor can be effectively used to visualize and detect the unbonded position of the CFRP sheet. In addition, In addition, the strain measured by the BOTDR sensor was found to be more effective in analyzing the overall structure behavior than the electric resistance strain gauge. The development of a BOTDR sensor with a measuring longth of less than 100 mm will enable accurate detection of the local unbonded position of the CFRP sheet.

• Economic and Environmental Geology
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• v.46 no.5
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• pp.445-453
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• 2013

The Uiseong Tapriri Five-Storied Stone Pagoda (National Treasure No. 77) is typical stone cultural heritage in Unified Silla Dynasty, Korea. The pagoda has been occurred black, brown discoloration and microcrack, exfoliation, granularity decomposition with white discoloration because of continuous weathering. As the results of analysis for the contaminants, chemical weatherings are generated that black contaminant by manganese oxide, brown contaminant by iron oxide, white contaminants by gypsum and taranakite. And physical weatherings, such as microcrack, exfoliation, are occurred by salt(gypsum) crystallization. Therefore, these need to remove the contaminants according to the conservation treatment manual, and regular monitoring using P-XRF to preserve long-term the Five-Storied Stone Pagoda at Tapri-ri, Uiseong.

• Conservation Science in Museum
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• v.9
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• pp.85-93
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• 2008

Conservation science team of the National Museum of Korea has conducted conservation treatment for 3 pieces of portraits as a part of project for publishing illustration book of relics of paintings and writings. Among them, portrait scroll of Jo Gyeong is a representative portrait of Seonmoogongsin rank in 17th century of Chosun, which was donated in 1997 and its whole body painted on silk was scrolled. This portrait was in poor state including the silk of portrait got loose from lining paper completely and exfoliation of the pigments. Accordingly before preservation treatment, production technique and the quality of the material lining were surveyed through scientific study(investigation through microscope, XRF, X-ray) and preservation treatment was conducted in order of disassembly, cleaning, removal of lining paper, infiling of the missing parts, lining, finishing.

• Journal of Conservation Science
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• v.19
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• pp.85-98
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• 2006

Rock property of the Seosan Maaesamjonbulsang is composed of biotite granite with medium grained texture. The triad Buddha is highly deteriorated by the joint, fracture, break-out, exfoliation, dew condensation of the surface and discoloration of the secondary pollutant. Host rock of the triad Buddha is divided dozens of rock blocks with various shape, and developed irregular discontinuity planes. Besides, the host rock is promoted biological pollution due to the surrounding crowded vegetation and high humidity environment. As the results of structural stability, it is confirmed that developed discontinuity system in the host rock is exposed instability sloping environment. Therefore, the host rock and surroundings are required maintenance, and required preservation by continuance monitoring for understand behavior of discontinuity system.

• Journal of Conservation Science
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• v.25 no.4
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• pp.383-398
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• 2009

We have investigated chemical properties of the pigments and carried out the deterioration diagnosis using nondestructive techniques of the wall painting in Yaksajeon Hall of Gwanyongsa Temple. As the results of pigments analysis, it was unusual that the cobalt was detected in the blue and green colors used to traditional paint background. According to the deterioration diagnosis, ultrasonic measurement and infrared thermography, dominant cracks and exfoliation caused by high content of moisture. Therefore, it should be devised effective plan to prevent penetration of water for the long term this wall painting.

• Journal of Conservation Science
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• v.35 no.5
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• pp.403-415
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• 2019

According to oral tradition, the King Sejo's palanquin is indeed the palanquin of King Sejo, the 7^th monarch of the Joseon dynasty who reigned from 1455 to 1468, which was left behind after visiting the Magoksa temple. The palanquin is painted in five colors, mainly black, white, yellow, red and green. The chromaticity measurement of the yellow pigment showed that orpiment and gold are a noticeable distinction between the lightness and b^⁎ values. In the case of the red pigment, a^⁎ values of areas painted with cinnabar tend to measure at high values. As a result of the optical microscopy, scanning electron microscopy and energy dispersive spectroscopy analyses, it was determined that Chinese ink was used for the black pigment, lead white and white clay were used for the white, and orpiment and gold for the yellow. The red pigment was found to be the result of minium, cinnabar and red ocher, atacamite was used as green pigment. Though the analysis results of the cross sections on very small exfoliation fragments of pigments, it was confirmed that white clay and lead white were used for the preparation layer. In addition, several coloration techniques were considered based on these analyses.

• Journal of Conservation Science
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• v.31 no.4
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• pp.457-476
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• 2015

This study is expected to present instructions and analysis of Modern Dancheong pigments by its physical characteristics. Search pigments currently used and experiments proper mixing ratio of Jangdanyuksaek(Incarnadine). Samples are made by based on presented a mixture ratio which is less exfoliation, cracks and color change. And put into accelerated weathering test and ultraviolet ray degradation test. As a result in case of Jidang($TiO_2$) Rutile type is superior in discoloration and durability. Rutile type makes color difference remarkably because of oil absorption difference while mixing with Jangdan. Water paints which are used as a alternative present yellowness which means water paints lack in durability. whiting should be taken carefully as it has high brightness after degradation.

• Journal of the Korean Wood Science and Technology
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• v.42 no.4
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• pp.393-406
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• 2014

To figure out the problems of flame retardant treatment (FRT) on wooden buildings, field investigation and analysis of statistical data are performed. After FRT on historical wooden building, efflorescence and exfoliation showed most often. These problems appeared especially on column, rafter and Ga-gu (Ingredients for supporting structure of a roof) which are liberally spreaded. To compare before and after FRT, analyzed 20 elements using P-XRF. In this process, found sulfur which informs FRT. This helped set up nondestructive assay. Through this process, confirmed field application by analysis residue component of Songgwang-sa Temple.

• Journal of the Korean Geographical Society
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• v.45 no.3
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• pp.342-359
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• 2010

The Bangudae Petroglyphs locate at Bangudong, Daegok-ri, Eonyang-eup, Ulju-gun, Ulsan and was designated as the No. 285 national treasure since 1995. After the construction of Sayeon-dam in 1965, there were many controversies of the rock weathering problems by the periodic immersion for approximately a few months. The isopleths of water content on the rock are drawn and the result shows relationships between the isopleths and distribution of joints or exfoliations. The distributions of water content rates in the Petroglyphs show the downward increasing pattern. This may suggest that the rates of water content are further influenced by the duration of immersion. Also, the upper part of the Petroglyphs with dense joints shows high rates of water content. If the water content rates in rocks increase, the water absorption rates increase too, because of the increasement of coefficient of permeability and porosity. The weathering damages of the Petroglyphs in which the pores are saturated by the periodic immersion are in the critical conditions.