• Journal of Mechanical Science and Technology
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• v.15 no.12
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• pp.1794-1800
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• 2001

Mass conservation is a key issue for accurate streamline and stream surface visualization of flow fields. This paper complements an existing method (Feng et al. 1997) for CFD velocity fields defined at discrete locations in space that uses dual stream functions to generate streamlines and stream surfaces. Conditions for using the method have been examined and its limitations defined. A complete set of dual stream functions for all possible cases of the linear fields on which the method relies are presented. The results in this paper are important for developing new methods for mass conservative streamline visualization from CFD and using the existing method.

• Animal cells and systems
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• v.3 no.1
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• pp.29-39
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• 1999

Current data on reproductive characters of endemic and native species are essential to provide a strategy for the conservation of these species. Red pine (Pinus densiflora Sieb. & Zucc.) is one of the dominant, native tree species in Korea, but its reproductive ecology is not well-known. In 1997, the pattern of variation in cone and seed yields contributing to the conservation of declining populations of red pines was examined. Plant height and dbh were measured, and several new cones were collected from each tagged tree after counting the number of cones on each tree. For a subset of cones sampled, the number of fertile scales, the number of seeds at three development stages (early/late aborted, and filled seed), seed wing size, wing color, and individual filled seed mass were measured. The three sites which differed significantly in mean plant size also differed in mean cone and seed production per plant. However further analyses showed that most variation in characters examined occurred among plants within sites, but not among sites. An average of 90% of the potential seeds on the cones aborted at an early developmental stage, demonstrating that early abortion is a major factor affecting the number of filled seeds per cone. Individual seed mass was the only character which exhibited significant variations among sites as well as among trees within sites. Individual seed mass was overall negatively correlated with both the percentage of late abortion and the number of old cones per plant, suggesting that both the past and current years' reproductive activities have caused variations in seed mass. The potential dispersal distance of red pine seeds is quite large. However, wing loading was correlated with seed mass and number in a complex pattern across the sites. Distribution of seeds with varied colored wings differed among sites and among trees within sites. These results suggest that red pines at different sites might possess different strategies to cope with selection pressures acting during the final phase of reproduction, from seed dispersal to establishment. Then the ‘fitted’ red pine trees at each site should be identified and managed to conserve or restore populations.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.269-275
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• 2013

Antifungal and insecticidal activity of Korean traditional medicinal plants was carried out to develop natural material for the development of organic cultural heritage conservation. As a result, Phellodendron amurense fruit was finally selected as a candidate of antifungal and insecticidal natural material. An novel active compound was purified from the ethylacetate fraction of Phellodendron amurense fruits using silica gel and Sephadex LH-20 column chromatography and PTLC. The compound was obtained as yellow oil form; UV ${\lambda}_{max}$(MeOH): 260 nm. The chemical structure of novel compound was determined as (4'-ethyl-2'-methylfuranyl)-6-methoxy-7-methylnona-2E,4E,6Z,8E-tetraenoic acid on the basis of various NMR experiments including $^1H$- and $^{13}C$-NMR, HMQC, HMBC and ESI-mass spectrum.

• Journal of Conservation Science
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• v.35 no.4
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• pp.363-372
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• 2019

Animal glue has been used as a binder in Dancheong since the Joseon dynasty. Binders play an important role in determining the physical characteristics of a painting layer. The analysis of binders can be used to identify the materials and techniques used in traditional Dancheong. Binders can be investigated using physicochemical component analyses methods such as gas chromatography/mass spectrometry, pyrolysis-gas chromatography/mass spectrometry, and fourier transform infrared spectroscopy, but the detection characteristics vary depending on the degradation properties of the pigment and binder. Therefore, cross-validation using a combination of physicochemical analysis and enzyme immunoassay is used to increase the reliability of the results. In this study, we present an enzyme-linked immunosorbent assay (ELISA) as an example of an enzyme immunoassay as a method for analyzing animal glue, a traditional binder used in Korea. The applicability of ELISA was tested using commercial animal glue, in addition to animal glue produced using a variety of extraction conditions. The animal glue was analyzed in a Noerok-additionally coated-replica sample to evaluate the possibility of analyzing the animal glue in a paint layer mixed with pigment. Based on the results, we performed an assay on the use of animal glue in the Dancheong sample of the temples of the Joseon dynasty, that are estimated to have been built in the 17^th century.

• Journal of Conservation Science
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• v.29 no.4
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• pp.297-309
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• 2013

Iron objects become corroded at fast speed from the moment when they are excavated, so it is needed to control corrosion through processes of conservation treatment. However, re-corrosion mostly takes place in excavate iron objects, although they have already gone through the process of conservation treatment, and it is more difficult to carry out the second conservation treatment of re-corroded excavated iron objects than the first conservation treatment, and it requires a longer period of time to treat them as well. In this study, aims to discover factors of re-corrosion by scientifically analyzing corrosion products generated during the process of storage after the process of conservation treatment. The finished on conservation treatment of the iron artifacts, which were unearthed from three ancient site in Gyeongju by using the same conservation method between 2002 and 2009, re-corrosion condition observed on the packaging-iron artifacts. Focused on 9 target forged iron artifacts among them, this study analyzed the physical changes by mass measurement, naked-eye and microscopic observations and the chemical changes by SEM-EDS, XRD, IC and ICP analysis. The results show that the yellowish brown corrosion products formed on the facing surface of part dropped from the artifacts had different associated forms but acicular shape. In addition, the acicular shape became clearer as the color changed from red to yellowish brown. According to the process when the conservation treatment was completed, the mass of the artifacts increased in proportion to the corrosion products and the chloride ion ($Cl^-$) concentration had a tendency to increase relatively. ${\beta}$-FeOOH (akaganeite) was confirmed in the XRD analysis for the corrosion products of all the collected samples. As a result of ICP analysis, $Na^+$ and $Ca^{2+}$ components were confirmed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.5
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• pp.28-37
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• 2010

This study is intend to evaluate natural conservation value, and to suggest natural park plan based on conservation value evaluation. In this study evaluation items are selected through related studies about ecological conservation evaluation, and evaluation items in this study can be classified into 2 aspects, ecological environment and topographic environment. After each evaluation items are overlaid with GIS program, management levels are derived from comprehensive overlaid maps of each evaluation items. Management areas can be classified into 5 levels; Critical Conservation Area, Conservation Area, Restoration Area, Passive Usable Area, Active Development Area and Settlement Area. So management areas can be matched each management levels to land use of natural park, that is district of preservation, district of natural environment, district of settlements and district of mass facilities. This study have good enough to evaluate ecological value for natural park plan, but, it is difficult to evaluate conservation value only with maps of each evaluation items, so it needs supplementary field survey for precise conservation value evaluation.

• Transactions of Materials Processing
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• v.12 no.2
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• pp.128-133
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• 2003

In this study, the momentum conservation type punching mechanism for micropunching system was developed to avoid the punch failure in the misaligned status between the punch and die. The punching energy can be precisely controlled by the falling height of the projectile mass and the intermediata mass, which contacts with the punch, transmit the energy to the punch with the same contact condition. The potential energy of the projectile mass is converted to kinetic energy at the light weight punch that the projection speed into the sheet metal workpiece can be accelerated. The butt formation characteristics for the alignment condition and for the projection speeds are investigated to verify the feasibility of the proposed punching mechanism.

• Conservation Science in Museum
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• v.9
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• pp.105-116
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• 2008

The Conservation Science Team of National Museum of Korea has established the data base of lead isotope ratio as the scientific research of bronze patina, which was acquired from conservtion process of metal objects, and based on this result, it intends to conduct the research related to the origin of raw material for the bronze objects. As the equipment for analysis of lead isotope ratio of the bronze patina, the thermal ionization mass spectrometer(TIMS) was used. As a part of this study, in 2nd year 2008, lead isotope ratios of total 18 samples inclding 2 samples of Round-type gold-bronze belong to Baekje period, the 2 items of head of bronze arrow belong to Nangnang(Lelang) and 10 items of the flower-shaped bronze dishes from the Unified Silla period, the 4 items of the bronze patina from the objects(era of 1 item not identified) of Wonpungtongbo(year 1078-North Sung) were analyzed.

• Journal of Conservation Science
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• v.37 no.4
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• pp.391-401
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• 2021

Outdoor sculptures of modern art works are being damaged and deteriorated as they are exposed to the outdoor environment due to the nature of exhibition in the outdoor environment, but secure of basic data through the measures for conservation and advanced researches still remain in the early stage. The surface of "Conversion" which is exhibited in the Busan Cheonmasan Sculpture Park has been exfoliated and deteriorated due to outdoor exhibition for a long time, so systematic conservation and management of works are considered necessary. Prior to the conservation and management, this study conducted observation of cross section, analysis of inorganic components, FT-IR, Raman and Py-GC/Mass analysis to examine the nature and type of paints used for the work through a scientific analysis. As a result of analysis, paints used for the "Conversion" include paint mixed with silvery aluminium powder and white pigment, reddish paint mixed with toluidine red, bluish paint that mixed prussian blue and titanium white and mixture of phthalocyanine blue and titanium white. The result is expected to be used as basic data for selecting materials necessary for conservative treatment of and establishing a plan for conservative treatment of the "Conversion".

• Journal of the Korean Society of Costume
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• v.58 no.5
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• pp.211-231
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• 2008

To conserve historic textiles, analyses of textile materials, pollutants and deterioration are prerequisite steps. Based upon analytical results, guides for conservation of historic textiles are established. In analyses of textile materials, pollutants and deterioration, there are chemical methods(burning, solubility and staining), physical methods(microscopy and density) and instrumental analysis(Fourier Transform Infrared Spectroscopy (FT-IR), Fourier Transform Raman Spectroscopy(FT-Raman), Gas Chromatography(GC), Mass Spectroscopy(MS), X-Ray Fluorescence (EDXRF, WDXRF), Energy Dispersive Spectroscopy(EDS), and X-Ray Diffraction(XRD), Tensile Testing Machine etc.). Combination of qualitative and quantitative analyses makes accurate diagnosis of textile condition possible. As examples of analyses and conservation of historic textiles, Chuninsan(19 century) similar to sunshade with handing down historic textile and golden decorative skirt(17 century) with excavated costume are taken.