• 보존과학연구
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• s.29
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• pp.163-182
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• 2008

Precise scientific-diagnosis for preserving stone cultural properties has been well-advanced, but research on proper methods for conservation, restoration and repair is still in early stage. Accordingly it is quite difficult to establish conservation treatment methods compatible to unique characteristics and environments of each cultural property. We tried to select most compatible conservation materials through thorough assessment of conservation materials in current use. This research is focused on conservation and restoration materials except cleaner, which are used as adhesive, filler, repellent and consolidant. Conservation treatments for stone cultural properties were first tested in 1960's and have been carried out by various methods under relevant organizations and conservation treatment companies since. We investigated present status of conservation materials being used for cultural properties. Based on these data, we will look through types and properties of the conservation materials to figure out existing problems. Among many kinds of resins, the ratio of conservation materials used in cultural properties is very low. Therefore, new conservation materials equipped with proved long-term stability should be developed as soon as possible.

• 보존과학연구
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• s.24
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• pp.5-28
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• 2003

Stone has been one of the most intensely studied materials in conservation. Understanding the deterioration of stone needs various knowledge in different mineralogical and physical characteristics and its weathering response under different climate and environment. The alteration and weathering of stone is affected by natural or artificial elements whether they are physical, chemical or biological damaging factors. It can be said that the bio deterioration of stone is coupled with every environmental factors, which induce decomposition of stone structure, either directly or indirectly as a form of catalysis. Many elements contribute to the deterioration of stone monuments and other objects of cultural value such as pagoda, stature of Buddha, etc. This report concentrates on the action of biodeteriorative factorsincluding bacteria, algae and higher plants. Preventive and remedial methods and a selection of chemical treatments are also described.

• Journal of the Korean Institute of Rural Architecture
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• v.4 no.1
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• pp.71-86
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• 2002

This research aims to illustrate the structure of the ancient Korean wooden buildings by a comparative study of the historical resources such as stone remains, wall paintings historiographies and excavations. As stone pagodas are the most typical stone remains, I selected for analysis some stone pagodas which contain architectural elements and results of the study are as follows: 1) The number of stories and structural modes of the base stone part show the wooden architectural aspects: they have one or two stories and their base part is constructed in the mode of assembling rectangular stones. 2) The body of the pagoda contains such architectural elements as pillars, door and windows, crossbeams, balcony, bracket sets. 3) The roof of the stone pagoda contains such architectural elements as eaves, roofs and modes of stone assembling. The results inferred through this research could be of help for further comparative studies with the other secondary materials by providing basic knowledge for it.

• Structural Engineering and Mechanics
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• v.65 no.1
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• pp.81-89
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• 2018

Stone column installation is a convenient method for improvement of soft ground. In very soft clays, in order to increase the lateral confinement of the stone columns, encasing the columns with high stiffness and creep resistant geosynthetics has proved to be a successful solution. This paper presents the results of three dimensional finite element analyses for evaluating improvement in behaviour of ordinary stone columns (OSCs) installed in soft clay by geotextile encasement under monotonic and cyclic loading by a comprehensive parametric study. The parameters include length and stiffness of encasement, types of stone columns (floating and end bearing), frictional angle and elastic modulus of stone column's material and diameter of stone columns. The results indicate that increasing the stiffness of encasement clearly enhances cyclic behaviour of geotextile encased stone columns (GESCs) in terms of reduction in residual settlement. Performance of GESCs is less sensitive to internal friction angle and elasticity modulus of column's materials in comparison with OSCs. Also, encasing at the top portion of stone column up to triple the diameter of column is found to be adequate in improving its residual settlement and at all loading cycles, end bearing columns provide much higher resistance than floating columns.

• 보존과학연구
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• s.28
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• pp.169-182
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• 2007

It is very difficult to attain stable and satisfactory result satisfaction from newly developed materials and methodologies for conservation of cultural properties. In order for an effective conservation method, it is necessary that the manual for application of the proper materials and its methodology should be set up. However, stone conservation value must be established in advance of the manual, because the philosophical concepts and the technical methodology are not standardized. In this study, therefore, the conservators' opinion about the conservation for stone artifacts was collected. The opinions were based on the questionnaire about cleaning of surface contamination on masonry, and hereafter those will be referred to the conservation method about stone artifacts.

• The Journal of the Korean dental association
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• v.38 no.8 s.375
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• pp.757-764
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• 2000

• The Journal of Advanced Prosthodontics
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• v.7 no.3
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• pp.199-206
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• 2015

PURPOSE. The present study investigated the influences of various gypsum materials on the precision of fit of CAD/CAM-fabricated prostheses and analyzed their correlation with surface roughness. MATERIALS AND METHODS. The master model of the mandibular right first molar was replicated, and four experimental groups based on two types of Type IV stone (GC Fujirock EP, Die keen) and two types of scannable stone (Aesthetic-Basegold, Everest Rock) were created to include a total of 40 specimens, 10 in each group. The surface roughness of the working models for the respective experimental groups was measured. Once the zirconia cores had been fabricated, the marginal and internal fits were measured with a digital microscope using the silicone replica technique. The mean and standard deviation of the respective points of measurement were computed and analyzed through the one-way ANOVA and Tukey's HSD test. The correlation between surface roughness and the precision of fit of the zirconia core was analyzed using the Pearson correlation analysis (${\alpha}$=.05). RESULTS. The zirconia cores fabricated from the scannable stone working models exhibited a superior precision of fit as compared to those fabricated from the Type IV stone working models. The correlation analysis results showed a clear positive correlation between surface roughness and the precision of fit of zirconia cores in all of the experimental groups (P<.05). CONCLUSION. The results confirmed that the surface roughness of dental working models has a decisive influence on the precision of fit of zirconia cores.

• Journal of Conservation Science
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• v.17 s.17
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• pp.5-18
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• 2005

Rock materials of the Stone Lantern in the Gwanchoksa temple was composed of dark grey granodiorite. This Stone Lantern is partly structural distortion as S-shape, especially, rocks of the upper supports and under the roof materials were highly deterioration due to the surface exfoliation, and strong secondary contaminations owing to the discoloration by oxidation of inserted iron plates between the rock properties, and white grey to dark black contaminants along the rain path way. Rock surface of the Stone Lantern occurred as partly green patches because of coated by algae, lichen and moss. This biological problems are need for cleaning and treatments. The Stone Lantern have to be considered to conservation method that can reduce weathering factors with long-term monitoring about environmental change for structural stability, surface degradation and mechanical weathering. Materials of the Stone Lantern and basement rocks of the area are consisted of same petrogenetic granodiotite based on occurrences, petrological and geochemical characteristics.

• Conservation Science in Museum
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• v.26
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• pp.1-12
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• 2021

The bisphenol A epoxy resin currently used for the conservation of stone cultural heritage items is known to suffer from yellowing discoloration. In order to mitigate this yellowing and explore the availability of more diverse materials for the conservation of stone cultural heritage items, a hydrogenated Bisphenol A-based epoxy resin was prepared and compared with the epoxy resin currently used in the conservation treatment of stone cultural heritage items. The newly prepared epoxy resin showed improved physical properties relative to the existing materials, especially in terms of tensile strength, adhesion, and machinability, while the yellowing discoloration was reduced by a factor of roughly five to eight. The results suggest that epoxy resin could be used as a stable material for the conservation treatment of stone cultural heritage items, most of which are located outdoors.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.717-724
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• 2003

Although sand compaction pile is applied considerably for increase of hearing capacity in domestic, it is getting more necessary to develope the alternative materials because of exhaustion and increase of unit cost of sand. In this study, stress concentration ratio between crushed-stone pile and soft ground was measured and, a displacement ratio 30, 40 and 50%, variation of stress concentration ratio was analyzed. As an increase displacement ratio, the stress concentration effect of crushed-stone compaction pile doesn't increase proportionally and effect of ground improvement in case of ground was good at displacement ratio 30% or 40%. The stress concentration ratio of crushed-stone compaction pile in group piles is 1.5 times that of crushed-stone compaction pile in single pile.