• Journal of Conservation Science
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• v.32 no.3
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• pp.353-364
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• 2016

The materials of sculptured stone property around the Hyeonleung Royal Tomb in Guri consist mainly of high weathered of granitic rocks with magnetite-series. Deterioration characteristics occurred highly with microorganism, soil inflow and black contaminants at the burial mound zone. As a result of deterioration evaluation, stone surface around the burial mound zone show serious comprehensive damage of soil inflow (50.5%) and lichen coverage (47.6%) which are the major damaging factors, and there are about 8.6% of biological growth noticeably in the north side. Surface contaminants and the discoloration had the complex causes. Gypsum occurred between joints of stones and the major contaminant type, darkening which was analyzed organic bodies caused discoloration. From result of ultrasonic velocity measurements, there are mean value of 2,195 m/s with highly weathered (HW) grade. Most of the stone properties showed 4 to 5 weathered grade. Therefore, it turned out that sculpture stone properties require conservation treatments. To remove soil accelerating damage factors and lichen occupying high percents, the cleaning process is necessary and consolidation, rejoining and filling are needed as well. Also, consideration on removing conservation materials containing Ca and e fflorescence is required and retreatments need to be considered.

• The Korean Journal of Quaternary Research
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• v.1 no.1
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• pp.3-20
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• 1987

With regard to the Quaternary formations in the Korean Peninsula, very few studies have been done specially from a stratigraphic viewpoint. The alluvial sediments filling in the valleys have often been considered as the only formation of Quaternary age (more precisely of the Holocone) and so the Pleistocene was regarded as an erosional or nondepositional episode. This is apparently evident from a quick look at the general geological maps of the Peninsula, which show a lithological sequence of Mesozoic or Paleozoic substrata immediately overlain by Holocene alluvium. Likewise, the Pleistocene period was described in terms of unconformity in most local or regional stratigraphical successions of the Peninsula. Recently several different types of Quaternary formation, besides the so-called Holocene alluvium in the valley plain have been found around the Peninsula. They consist of coastal deposits, marine or fluviatile terrace deposits, ancient valley fill deposits or slope deposits. Some parts of the volcanic sediments in Jeju Is. are also known as the Quaternary sequence. Thus the Quaternary deposits in the Peninsula are far more developed than previously known to gelolgists. Moreover the importance of Quaternary research became recently apparent in Korea due to the shortage of raw materials and to the policy of an optimum land-use. Advanced constructions and land reclamation have required more precise engineering parameters of loose materials and an estimation of land stability. This does not imply only the engineering, or the structural properties of the loose material, but at the same time the basic study of the sediments from the stratigraphical and environmental viewpoints has been necessary. In this connection, Quaternary outcrops specially along the coastal fringe of the Peninsula have been mapped, profiled and sampled for sedimentological, clay-mineralogical and palaeomagnetic studies. All these results are compiled for the core of the Quaternary stratigraphy of the Peninsula.

• Food Science and Preservation
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• v.23 no.3
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• pp.422-431
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• 2016

To investigate the causes of the thermal deformations of packaging materials when microwave-heating ready-to-eat sauce products packaged in stand-up pouches, patterns of temperature changes were determined using an infra-red thermal imaging camera, a thermo-sensitive tape, and a fiver-optic thermometer. The temperature distributions of spicy chicken sauce and Indian curry samples in a stand-up pouch were found to be uneven during micrewave heating. A sharp increase in the temperature was detected, especially above the filling layers and in the corners of sealing layers of the package. The temperature measurements using an infra-red thermal imaging camera are restricted to the surface, and therefore might underestimate the actual temperature. Using a thermo-sensitive tape, temperature up to $200^{\circ}C$ were measured in the spicy chicken sauce sample showing package deformation. When the temperature is measured using a fiber-optic thermometer, it is crucial to have precise sensor performance to accurately measure the temperature in a narrow hot-spot area of the package. In this experiment, the fiber-optic thermometer was attached to a GaAs crystal sensor, which obtained more sensitive and accurate temperature measurements than those by a convectional sensor.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.1
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• pp.15-24
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• 2001

The purpose of this study is to evaluate the tissue response in applying of various bone substitutes included toothash-plaster mixture, resorbable hydroxylapatite (HA) and demineralized freeze-dried bone and to show the clinical usefulness of toothash-plaster mixture for the repair of craniomaxillofacial bone defect. For this experiment, 100 Sprague-Dawley rats weighing 200gm or more were used. There were four experimental groups: group I, toothash-plaster mixture; group II, demineralized freeze-dried bone; group III, resorbable HA; and group IV, control group. A full thickness, round bone defect measuring 10mm in diameter was created in the midcranium, and the substitutes cited above were embedded in the experimental rats based on their group assignment. Blood clot was filled in the rats assigned to the control group. Experimental rats were sacrificed on the 1st, 3rd, 5th, 8th, 12th and 24th week after implantation and stained with the hematoxylineosin, Masson's Trichrome, using Van Gieson's stain method, and were examined under light microscope. The results were as follows: 1. In all the groups, prominent inflammatory reaction and the infiltration of multinucleated giant cells were noted during the early stage. Gradual healing decreased this reaction. 2. Among the rats in the experimental group II, which were given demineralized freeze-dried bone implants, active formation of new bone traveculae manifested. Chondroid tissues appeared, and it was suggested that the defect was filled with newly formed bone by virtue of osteoinductive activity. On the 12th week after the experiments, most of the defect was filled with newly formed bone trabeculae. 3. In experimental groups I and III, it was noted that HA manifested a healing process similar to that characterized by the toothash-plaster mixture, but inflammatory reaction was more prominent in experimental group I. Active osteoblasts were observed along the periphery of osteoid tissues, while newly formed bone trabeculae appeared adjacent to the implanted materials three weeks later. Formation increased to the extent that newly formed bone trabeculae fused directly with the host bone. Increase in new bone ingrowth into the filling materials was revealed by both experimental groups. 4. In the control group, new bone formation adjacent to the host bone was observed, but most of the defect was filled with mature connective tissue 24 weeks after the experiments.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.4
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• pp.624-632
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• 2006

In recent years, xenon plasma arc lamp was introduced for high-intensity curing of composite filling materials in direct resin restorations. In this study, two types of restorative materials, namely composites point $4^{(R)}$ and $Z250^{(R)}$ were selected and curing was conducted using a conventional halogen light and two plama curing lights. Two different resin composites were cured using the different units($Flipo^{(R)}$, Ultra-lite 180A, and $TriLight^{(R)}$) and tested for microhardness. The purpose of this study was to test the hypothesis that exposure to a plasma curing lamp for 3, 6. 9 seconds is equivalent to 20 or 40 seconds of irradiation using a conventional halogen curing unit. 1. $Flipo^{(R)}$ and Ultra-lite 180A were able to polymerize point $4^{(R)}$ at 6 seconds to a degree equal to that of the $TriLight^{(R)}$(control) at 40 seconds. 2. $Flipo^{(R)}$ was able to polymerize $Z250^{(R)}$ at 9 seconds to a degree equal to that of the $TriLight^{(R)}$(control) on the bottom surface at 20 seconds. whereas Ultra-lite 180A could not do. 3. Two plasma curing units were able to cure the test-composites with bottom/top ratios approximately 61% to 96% at 3 to 9 seconds. There were some differences between the two composite brands, with $Z250^{(R)}$ displaying less difference between top and bottom hardness values. For point $4^{(R)}$ and $Z250^{(R)}$, at least 6 or 9 seconds were necessary to produce microhardness equivalent to that of the $TriLight^{(R)}$ curing at 20 or 40 seconds.

• Journal of Marine Bioscience and Biotechnology
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• v.7 no.2
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• pp.58-70
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• 2015

Injectable RGD-bioconjugated Mussel Adhesive Proteins (RGD-MAPs) composite hydroxypropyl methylcellulose (HPMC) hydrogels provide local periodontal tissue for bone filling in periodontal surgery. Previously we developed a novel type of injectable self-supported hydrogel (2 mg/ml of RGD-MAPs/HPMC) based porcine nano hydroxyapatite (MPH) for dental graft, which could good handling property, biodegradation or biocompatibility with the hydrogel disassembly and provided efficient cell adhesion activity and no inflammatory responses. Herein, the aim of this work was to evaluate bone formation following implantation of MPH and collagen membrane in rabbit calvarial defects. Eight male New Zealand rabbits were used and four circular calvarial defects were created on each animal. Defects were filled with different graft materials: 1) collagen membrane, 2) collagen membrane with MPH, 3) collagen membrane with bovine bone hydroxyapatite (BBH), and 4) control. The animals were sacrificed after 2 and 8 weeks of healing periods for histologic analysis. Both sites receiving MPH and BBH showed statistically increased augmented volume and new bone formation (p < 0.05). However, there was no statistical difference in new bone formation between the MPH, BBH and collagen membrane group at all healing periods. Within the limits of this study, collagen membrane with MPH was an effective material for bone formation and space maintaining in rabbit calvarial defects.

• 한국지구물리탐사학회:학술대회논문집
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• 2004.08a
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• pp.138-156
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• 2004

GPR(Ground Penetrating Radar) was used for imaging the interior of the historical masonry such as stone pagoda in order to provide the basic information of safely inspection. The scope of the imaging was restricted to the foundation part of stone pagoda that transferred the load of the pagoda to the ground. Kirchhoff migration and traveltime tomography was used for imaging the outer stone and the inside of stone pagoda, respectively. From the migrated images, we could measure the thickness and the shape of the boundaries of the outer stone in the foundation part. From the reconstructed tomograms for the physical model, we could get the GPR propagation velocity distribution and exactly find the position of the air in the model and calculate the average velocity with respect to the different filling materials. The properties and the shape of the interior materials of stone pagoda can be basic informations for the safety inspection.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.592-599
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• 2002

Objective : The purpose of this study was to evaluate the effects of several light curing methods and several adhesives on the microleakage of composite resin restorations in primary teeth. Materials and methods : In 150 extracted human primary anterior teeth, O-shaped cavities were prepared in the labial surface ; the cavity diameter and depth were 1.6mm. The cavities were filled with light-activated composite resin, Compoglass. Four kinds of adhesives were used. Each filling materials were polymerized with three light cure methods. The restorations were polished using Sof-Lex discs(3M Co., USA). The samples were thermocycled 1,000 times between $5^{\circ}C$ and $55^{\circ}C$ with a 1-minute dwell time. Then, they were immersed in a 2% methylene blue solution(pH 7) for 12hours. Subsequently they were sectioned labio-lingually through the center of the restoration with a diamond saw at low speed with a water coolant, and evaluated by stereomicroscopy. Microleakage analyses were done, using scores from 0 to 4. Results : Results showed the least microleakage in Compoglass group(P<0.05). There were less microleakage in SBMP group among the adhesive groups, but no significant difference was observed(P>0.05). And there were no significant differences among the groups depending on curing methods(P>0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.498-508
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• 2002

The purpose of this study was to compare the amount of fluoride release and remineralizing effect of compomer with those of glass ionomer cement and composite resin. Composite resin($Z-100^{(R)}$) was used for negative control group(Group I), glass ionomer(Fuji II $LC^{(R)}$) for positive control group(Group IV), compomer(Dyract $AP^{(R)}$ and $F-2000^{(R)}$) for experimental group(Group II and Group III). The results obtained can be summarized as follows : 1. Glass ionomer showed the higher amount of fluoride release than compomer groups. Composite resin showed no fluoride release during test period. 2. Significant evidence of remineralization could be noticed in samples of all groups. The highest degree of remineralization was observed in glass ionomer group followed by compomer group. The least evidence of remineralization was observed in composite resin group. 3. Microhardness values of carious site was lower than control site, but Microhardness values of caries site at form away from filling materials in group II, III, IV was significantly higher than the other area. Based on the above results, compomer could be considered as one of the very attractive restorative materials in the field of pediatric dentistry.

• Analytical Science and Technology
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• v.9 no.4
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• pp.382-391
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• 1996

In this study, 12 different chemical species of fine ceramic($BaTiO_3$) were synthesized as the standard materials for the fast and accurate measurements of X-ray fluorescence spectrometry. Samples were diluted to sixteen times with the filling compound ($Li_2B_4O_7+LiBO_2$) in order to remove the matrix effect, and to get the convenient storage and homogeneity of ingredients. The matrix effects among the ingredients were corrected by the empirical coefficient method based on the Lucas-Tooth and Price model. The standard curve on 12 standard materials containing 15 elements were obtained by using X-ray fluorescence spectrometry at three different laboratories. The correlation factors of BaO, PbO, SrO, $Fe_2O_3$, $La_2O_3$, $SnO_2$, ZnO, $ZrO_2$, CaO indicated the relati vely good agreement over 0.995 among the three different laboratories. $SiO_2$ and $Al_2O_3$ showed the poor linearity because of their low fluorescence intensities.