• Journal of the Korean earth science society
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• v.37 no.1
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• pp.11-20
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• 2016

Diatoms were studied from the trench sediments around Bangudae petroglyphs in order to better understand the depositional environment before and after the construction of Sayeon dam in Ulsan. There were no diatoms produced from the sediments before the dam construction while the diatoms were produced from the sediments (depth of trench 228 cm) after the construction of the dam. Seventy-five species of diatoms of 27 genera were identified in the trench sediments. The number of diatom valves per gram of dry sediment ranged from $0.2-5.8{\times}10^5g^{-1}$. Four diatom assemblage zones were identified according to the frequency of critical taxa as follows: assemblage zone I, from 228 to 150 cm; assemblage zone II, from 150 to 122 cm; assemblage zone III, from 122 to 62 cm; and assemblage zone IV, from 62 to 0 cm. In addition, based on the environmental indicator species, an analysis was carried out to measure eutrophication, acidity and $Cl^-$ value. Results of the eutrophication and $Cl^-$ values were as follows. Based on the lower 74 cm horizons, the degree of eutrophication middle-high to $Cl^-$ values were lower, upper horizons appeared to eutrophication in the low, and $Cl^-$ values were high. Acidification from low horizons of 122 cm showed a neutral-alkaline degree whereas it exhibited acid in the upper part. In particular, regarding nutrients (TP and TN), the index taxa showed a higher TP value at 175 cm while higher TN value at 62 cm.

• Journal of the Korean Applied Science and Technology
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• v.29 no.1
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• pp.108-115
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• 2012

Archaeological waterlogged woods found under the sea, in lakes, or in swamp environments are generally weak and fragile. If waterlogged wood materials were taken out of the water and left without modification, they would collapse and lose their original dimensions completely. Conservation is performed to replace the water with chemical agents and to give dimensional stabilization and durability. EDTA and PEG are the most commonly used in the preservation of wood. pH control-precipitation method is used for recovery of EDTA from waste fluid of archeological waterlogged wood conservation treatment. The black substance is eliminated from wood as Fe-EDTA complex are formed and EDTA is separated and precipitated from Fe-EDTA complexes at pH 2.68 or less. The result of analysis of the precipitated products and the commercial EDTA by FT-IR and FE-SEM showed that precipitated product by pH adjusted was not a type of Fe-EDTA complex, but pure EDTA. Waste fluid produced in PEG treatment shows the black color and has an offensive odor by organic matter extracted from wood. Color of waste fluid is decolored with oxidation reaction by peroxy hydrate. In FT-IR and SEM-EDX of PEG after freeze-drying process, no significant change of functional groups induced from oxidation is observed, and any metal ion does not exist in the solid PEG specimen. The molecular weight of PEG is measured using GPC and viscometry. Properties of PEG before and after preservation treatment, and after oxidation with $H_2O_2$ were not changed. Consequently, the peroxidation with $H_2O_2$ is a reasonable and simple method to decolor the used PEG solution.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.249-256
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• 2001

The objective of this study was to analyze characters of the vegetation structure, vegetation-environment relationships of Kyeryongsan forest community. Fifty plots were sampled in the valley forest of Donghaksa, Gabsa, Sanghasinri and Shinwonsa regions in Kyeryongsan. Field survey was carried out in August of 1999 to examine a vegetation type and measure a diameter. The classification by TWINSPAN, the DCCA ordination, and structure of stand were used to analyze data. The results of this study are as follows : 1. With the classification by TWINSPAN, the community was categorized into four groups, such as Carpinus laxiflora, Quercus variabilis-Quercus serrata, Zelkova serrata-Celtis jessoensis and Carpinus cordata communities. 2. The dominant species in Carpinus laxiflora community were Carpinus laxiflora, Quercus variabilis, Quercus serrata, Pinus densiflora and Styrax japonica. The dominant species in Quercus variabilis-Quercus serrata community were Quercus variabilis, Quercus serrata, Styrax japonica, Castanea crenata and Platycarya strobilacea. The dominant species in Zelkova serrata-Celtic jessoensis community were Quercus serrata, Castanea crenata, Lindera erythrocarpa, Zelkova serrata and Styrax japonica. The dominant species in Carpinus cordata community were Carpinus cordata, Carpinus laxiflora, Sapium japonicum, Cornus controversa and Zelkova serrata. 3. The results of the correlation between Kyeryongsan valley forest community and environmental factors by DCCA ordination method are as follows; The Carpinus laxiflora community was found in low elevation and steep slope area. The Quercus variabilis-Quercus serrata community was found in low elevation and lower slope area. The Zelkova serrata-Celtis jessoensis community was found in high elevation and lower slope area. The Carpinus cordata community was found in high elevation and midium slope area.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.4
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• pp.120-131
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• 2014

Sajikdan(a sort of national shrine in Korea) built at the time of foundation of Joseon was entrenched into Sajik Park going through Japanese colonial era and recently the efforts to restore it is in progress. The details of change in Sajikdan in terms of diachronic analysis are as follows: Firstly, the first period refers to one prior to Japanese colonial era from the first king (also named as "Taejo" in Korean) of the Joseon Dynasty, during which it secured and strengthened the presence as a place for performing important national rites in a nation. It was built on the foot of Inwangsan Mt. at the time of the first king in Joseon Dynasty at first, was destroyed fully by fire during a Japanese Invasion period to Korea(1592-98) and afterward its ancestral ritual facilities were completed under the regime of Youngjo. However, as Japanese intervention coming to the fore, its place was destroyed and then ancestral rites were also abolished in 1908. Secondly, next period falls on 1910 to 1944 when it was transformed and entrenched into a park by the Japanese Empire. While facilities related to a park and an heterogeneous building around the part of boundary were set up, the area of altar, a ritual house and d door of Sajikdan were also designated as historical remains and treasures. Thirdly, this period refers to one from Korea's liberation year from Japanese colony(1945) to the year of 1984 when it had a mixed placeness with the statues, monuments and buildings with heterogeneous nature built. Furthermore, a door of Sajikdan was removed and reconstructed over twice due to opening of Sajik Tunnel. Fourthly, a final period falls on 1985 to the present when efforts are in progress to restore the historicity and symbolism of Sajikdan. A plan for restoration is promoted but now is a difficult time suffering from troubles caused by residents' resistance. Scrutinized historical researches through excavation investigation and residents' understanding are required altogether for restoration of Sajikdan.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.4
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• pp.73-84
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• 2014

This research has conducted historical data analysis and on-site investigation on Chungam Pavilion and Seokchun Valley in Bonghwa. Based on the results, the original planting form was identified, and the vegetation management were drawn up. The results of this study can be summarized as follows. First of all, The Book of Seokchun states that there used to be forest trees such as pine tree, saw-leaf zelkova and maple tree, and flowering trees such as peony, royal azalea, rose, chrysanthemum, and lotus, planted around Chungamjeong. Around Seokchunjeongsa, there used to be boxwood, bamboo, maple, peach, gooseberry and peony planted in the area. Through this discovery it can be realized that the vicinity of Chungam Pavilion and Seokchunjeongsa provided not only the grand aesthetics of four clear seasons, but also planting landscapes with various symbolistic significance and meanings. The description of the planting situation in the historical records offers a useful reference for future vegetation management in Chungam Pavilion, Seokchunjeongsa and surrounding valleys. Furthermore, it holds critical value in the identification of planting pattern in late Chosun dynasty. Second, the planting landscape in and around Chungam Pavilion and Seokchunjeongsa will have to be maintained as described in the historical records The Book of Seokchun. Also, the once famous colony of pine trees in the area is gradually reducing in its scale, which calls for active management measures such as elimination of broadleaf trees.

• Journal of Conservation Science
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• v.33 no.5
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• pp.371-380
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• 2017

To investigate the pigments used in modern and contemporary oil paintings, thirty-two paintings by Jiho Oh and Bonung Gu were selected. The white pigment found in the ground and painting layers was identified as lead white (hydrocerussite), zinc white (zinc oxide), titanium white (titanium dioxide in anatase or rutile forms), calcite (calcium carbonate), and barite (barium sulfate). Further, this indicated that pigments differ according to the artist and date of the painting's creation. However, both Oh and Gu used zinc white during the modern and contemporary period, while lead white was replaced by titanium white, barite and calcite. Compared with the overseas studies on pigments and oil paints, the change patterns of pigments were the same with them but the periods of the use were partially different. It seems to be due to the fact that South Korea is linked to the historical background of the art material which was imported from Japan instead of Western countries. Therefore, it is inevitable that any change in the white pigments used for domestic oil paintings occurred at a different time from global transitions. If the results of this study are used in the analysis of art works it is suggested that a database recording such aspects as material properties of oil paints, artistic techniques, and chronology would become important for future conservation science and the study of art history.

• Journal of Conservation Science
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• v.34 no.5
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• pp.319-331
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• 2018

The collection of the National Museum of Modern and Contemporary Art, Korea, features a sansu folding screen that was created in 1940 to commemorate the sixtieth birthday of Soseok Kang Jin-Koo. It was created by six oriental painters, who were among the ten best painters in that era. The folding screen has been previously repaired and restored; however, owing to damage such as twisting of its wooden frame, abrasion, and moisture stains, rigorous conservation treatment is required. Hence, scientific research was conducted to analyze the textile, paper and pigments employed while creating the folding screen, to identify the associated material properties. Results showed that the textile used in the screen's picture and janghwang comprise synthetic fibers and natural fibers such as cotton and silk. Various types of papers were used in the folding screen, such as those from mulberry, herbaceous, and coniferous fibers. Furthermore, calcite deposits were found on the base of every picture, and certain colors employed by the artists appear to be produced from different pigments.

• Journal of Conservation Science
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• v.34 no.5
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• pp.379-385
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• 2018

This study examined the condition of degraded plastic artifacts and conducted materials assessments for conservation treatment. The properties and bond characteristics of five types of adhesives(EVA, PVAc, Cyanoacrylate) were evaluated to select the adhesive most suitable for conservation treatment. The degradation of plastic artifacts caused cracks, peelings, and surface warping. According to the FT-IR analysis, the synthetic resin used in the artifact was estimated to EVA type. The properties of the adhesives were evaluated through acidity, and hardness measurements. The results showed that acidity varies with the type of adhesive, and that the hardness of PVAc was higher than those of EVA. On comparing the bond characteristics of the samples after artificial degradation, it was found that PVAc and Cyanoacrylate increased the chromaticity and hardness of the samples, while EVA was the most stable with relatively little change. Thus, EVA was confirmed to be the most suitable materials for conservation treatment of degraded plastic artifacts. In this study, as the experiment of treatment materials based on actual artifact, it is expected that it could be used a basis research for conservation treatment of plastic artifacts.

• Journal of Conservation Science
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• v.36 no.5
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• pp.351-367
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• 2020

The pigments of three old and new celestial charts folding screens(『Celestial Chart(Folding Screen)』 and 『Old and New Celestial Charts, Eight-Panel Folding Screen』 of National Folk Museum of Korea and 『Koudou-Nanboku-Ryousouseizu』 of National Diet Library of Japan) were analyzed to estimate their dating. It was estimated that the 『Celestial Charts(Folding Screen)』 was painted using traditional pigments from the Joseon dynasty such as azurite, indigo lake, malachite, atacamite, vermilion, iron oxide, cochineal, gamboge, orpiment, lead white, talc and soot. The green and blue colors of the 『Old and New Celestial Charts, Eight-Panel Folding Screen』 and 『Koudou-Nanboku-Ryousouseizu』 were painted using artificial inorganic pigments such as emerald green and ultramarine blue. These pigments were imported from Europe post the mid-19th century. In the 『Old and New Celestial Chart, Eight-Panel Folding Screen』, only artificial inorganic pigments were used for green and blue colors. However in the 『Koudou-Nanboku-Ryousouseizu』, emerald green and atacamite in green color, and ultramarine blue and indigo lake in blue color were used together. Based on both the results of pigment analysis and the study of star charts and inscriptions, the 『Celestial Charts(Folding Screen)』 was painted post mid-18th century. The 『Koudou-Nanboku-Ryousouseizu』 and 『Old and New Celestial Charts, Eight-Panel Folding Screen』 were painted after green and blue artificial pigments were imported in the mid-19th century. The 『Koudou-Nanboku-Ryousouseizu』 in which both traditional and western artificial pigments were used, can be dated earlier than the 『Old and New Celestial Chart, Eight-Panel Folding Screen』.

• Journal of Conservation Science
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• v.6 no.1 s.7
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• pp.15-30
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• 1997

The chamical and physical properties of the fragments of an ancient pottery such as earthenware, gliazed pottery and celadon excavated in Chonnam province has been investigated by X-ray diffraction inductively coupled plasma spectroscopy(ICP), thermal mechanical analysis(TMA). Glazed pottery fragments of Chonnam province are cotaining Fe2O3 $4\~7\%$ by the analyis of ICP, firing temperature range was presumed to $1100-1150^{\circ}C$ by TMA. Celadon fragments of Chonnam province are containing Fe2O3 $2\~3\%$ by the analyis of ICP, firing temperature range was presumed to $1140\~1200^{\circ}C$ by TMA. The charateristics in the trace element composition of an ancient pottery of Chonnam provinceis are similar, it is an reflection of similar geological charateristics. The charateristic elements of Chonnam provincical ancient pottery were Rb, Sr, V, Zr, Y, Nd, Sc, La, Ce, Nb, Sm, Eu, Dy and Yb of the analyzed 21 trace elements. By Fe2O3-Zn ditribution diagram, potteries excavated in Yong-am, celadons excavated in Haenam, Kangjin, Buan and glazed pottery excavated in Hae-nam are grouped into the same class.