• Proceedings of the KSEEG Conference
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• 2000.04b
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• pp.247-248
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• 2000

• Journal of Conservation Science
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• v.22
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• pp.121-134
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• 2008

The mechanism of stone exfoliation and its cause in relation to chemical weathering by soluble salt were studied. Chemical, mineralogical and physical analysis was performed in exfoliation samples from stone monuments. The representative salt is gypsum in the exfoliation samples. In order to understand the salt reaction, stone samples(tuff and granite) were treated with two type of the salt, gypsum and sodium sulfate, which have different solubility. The capillary water uptakes are slight increased in impregnated with Na2SO4 and weathering simulation of two rock types. It means that the rock is deteriorated in the near of the surface by $Na_2SO_4$. $CaSO_4{\cdot}2H_2O$ bring out the thicker exfoliation than $Na_2SO_4$ because it is penetrated into the deeper zone and amount of accumulated salt is more abundant in the inner part than in the near of the surface. The exfoliation was formed in the tuff by salt treatment and 30cycle of weathering simulation, but there are not significant symptoms of exfoliation in the granite by same condition. This result was caused by the different capillary water uptakes and porosity of the rocks. In the tuff, salt solutions are penetrated into the inner part due to its high capillary water uptakes and porosity but the granite, which has low value relatively, can be formed thinner exfoliation.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.1
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• pp.119-125
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• 2005

A kind of mineral water obtained from the basing of deep under the sea was reported to have a characteristic mineral composition and its effect on the quality of Kimchi was evaluated in this study. Kimchi samples were prepared with NaCl and the mineral water under rock floor as sources of salt together with fermented seafoods and fermented at 20 for 6 days. The qualities of Kimchi were evaluated by analyzing the pH, acidity, number of viable cell, lactic acid bacteria, sensory properties and texture profiles during fermentation. The pH and total acid contents were not different among Kimchi samples. The microbiological changes were not observed in the samples. The sensory scores of Kimchi containing NaCI and fermented sandlance sauce, and of Kimchi containing the mineral water under sea rock floor with fermented seafoods were significantly higher than those of the others. On the other hand, Kimchis prepared with NaCl alone or mineral water under sea rock floor alone earned the lowest sensory scores among the tested samples with an exception of firmness of the sample made with the mineral water. As the Kimchi fermentation proceeds, the hardness value of Kimchi prepared with the mineral water became higher than that of Kimchi with NaCl. This study suggests that the mineral water under sea rock floor could be useful to keep the texture of Kimchi firm during the fermentation.

• Conservation and Restoration of Cultural Heritage
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• v.1 no.1
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• pp.29-37
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• 2012

The West Stone Pagoda at Gameunsaji Temple Site constructed in the 7th century is mainly composed of dark grey dacitic tuff bearing small numerous dioritic xenoliths. These xenoliths resulted in small holes due to differential weathering process from the host rocks. Physical strength of the pagoda was decreased due to weathering and damage caused by petrological, biological and coastal environmental factors. The southeastern part of the pagoda was extremely deteriorated that the rock surface showed exfoliation, fracture, open cavity, granular decomposition of minerals and salt crystallization by seawater spray from the eastern coast. The stone blocks were intersected by numerous cracks and contaminated by subsequent material such as cement mortar and iron plates. Also, the pagoda was colonized by algae, fungi, lichen and bryophytes on the roof rock surface and the gaps between the blocks. As a result of ultrasonic test, the rock materials fell under Highly Weathered Grade (HW) or Completely Weathered Grade (CW). Thus, conservational intervention is essentially required to prevent further weakening of the rock materials.

• Journal of The Geomorphological Association of Korea
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• v.25 no.3
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• pp.19-42
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• 2018

In this study, we surveyed weathering progressing aspect by major elements variation and rock hardness by using XRF analysis, schmidt hammer, and thin section analysis. This observation suggested that the weathering process is likely to develop differently according to microstructural characteristics. R-value on the inside wall are lower than those on the outside. Also, the shadier the environment was, the closer it was to inshore areas, the R-value appeared to be lower. The movement of the elements such as Ca, Na and K shows that feldspar is hydrolyzed and can form salt crystallization like a gypsum or halite when they combine with the elements such as S or Cl. It proved a high CaO, $Na_2O$ and $K_2O$ content on flaking inside wall and rock meal. The exfoliation was mainly observed along the shady backwall and ceiling of tafoni. This helped in predicting the growth of tafoni as well as the direction of its progress.

• Journal of Conservation Science
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• v.25 no.2
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• pp.131-145
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• 2009

Goryeong Yangjeondong Petroglyph on the joint face of the bedrock (6m in width, 3m in height) composed of the green sandstone has circles and shield pattern sculptures. The rock is mainly composed of quartz, feldspar, chlorite, illite and calcite with the clay minerals. These clay minerals occur as pore lining, replacement of component and pore fillings. Investigated the weathering aspects including the connection between soluble salt and rock weathering and the stability of the bedrock with petroglyphs. The Major deterioration aspect are grain peel-off, surface exfoliation, cracks and damage. And the bedrock where the joints and cracks advance is interpreted with the fact that has the possibility of the falling rock. For conservation, adhesive need to cover crack and damage and consolidation is necessary in the surface which becomes weak.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.444-446
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• 2003

Mogao Grottos are located at the eastern foot of the Mingsha Mountain, 25km southeast of Dunhuang City. The caves were excavated into the cliff on the west bank of the Daquan River. The wall paintings in the caves are subject to the severe deterioration generated by recrystallization of salt. It relates with the movement of water/moisture in rock formation. Through the satellite image analysis and geological survey it has been clarified that the movement of ground water is governed by the fault system. The geographical nature is specified by the aggressive tectonic movement from the south.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.586-589
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• 2001

In this study, phosphate was produced through the solublization of hydroxyapatite and rock phosphate by Pantoea agglomerans, and it was examined the possibility of solublizing insoluble phosphate salt by immobilized P. agglomerans on Ca-alginate bead as support. 520mg/L of phosphate was solublized when P. agglomerans was cultured in HY meclium at $30^{\circ}C$, pH7, 100rpm, during 48hours culture. And solublized phosphate amount was 86.09mg/L when hydroxyapatite in the HY medium was exchanged to rock phosphate. In case of being used immobilized P. agglomerans. 740mg/L of phosphate was solublized in the HY medium, during 120hrs in the same condition. And 182mg/L of phosphate was solublized when rock phosphate was added instead of hydroxyapatite.

• Journal of the Korean GEO-environmental Society
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• v.5 no.4
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• pp.13-24
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• 2004

This study was carried out to plan the prevention of the generation and discharge of Acid Rock Drainage (ARD). The Acid Base Accounting(ABA) test was performed for geological materials such as pit wall, waste rock and stream sediments near the Imgi abandoned pyrophyllite mine in Busan, Korea. In addition, hydraulic characteristics were tested with the disk tension infiltrometer around the waste rock dump. Maximum Potential Acidity(MPA) of geological materials near the Imgi mine was 246.942kg $H_2SO_4/t$, and maximum Acid Neutralising Capacity(ANC) was 8.7kg $H_2SO_4/t$. These results indicate the pit wall and waste rock, except most of stream sediments are acid generating geological materials. These have salt and free hydrogen ion which resulted from oxidation of sulfides. Hence they could be convert rain water to acid rock drainage. Although the waste rock dump of the Imgi mine have very low infiltration rate, slopes of the waste rock dump have many "V" type erosion gullies and multi-layers. These gullies and multi-layers have coarse clastic particle layers which have very large hydraulic conductivity. Through this coarse clastic particle layer a large part of rain flow into ground. And also this layer could function as aeration path which induced oxidation of sulfide minerals and generation of ARD continuously.

• Geomechanics and Engineering
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• v.30 no.1
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• pp.45-49
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• 2022

In the present study, a physical model was built for the Jintan underground gas storage cavern group according to the similarity theory. In this regard, four ellipsoid caverns were built with scaled in-situ stresses and internal pressure. Then the stability of underground caverns was analyzed. The obtained results demonstrate that loss of internal pressure adversely affects the safety of caverns and attention should be paid during the operation of gas storage.