• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.255-261
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• 2002

The purpose of this study was to compare the microleakage pattern of flowable composite resin to sealant, composite resin used in preventive resin restoration and glass ionomer cement used as liner. 120 extracted sound human molars were divided into 6 groups : group 1 and 2:sealant ; group 3 and 4:preventive resin restoration ; group 5 and 6:sandwich technique restoration. For the experimental groups(group 2, 4 and 6), flowable composite resin(Tetric flow) was used. For the control group, Concise was used as sealant material(group 1), Z-100 with Concise were used as preventive resin restoration(group 3), and Vitrebond was used as cavity liner(group 5). All the restorations were thermocycled and the degree of dye penetration was evaluated with stereomicroscope. The microleakage of each group was measured and statistically analyzed. The results of the present study were as follows : 1. In group 1 and 2, there was no statistically significant difference in microleakage between Concise and Tetric flow(p>0.05). 2. In groups of preventive resin restorations, there was no statistically significant difference in microleakage between Z-100 with Concise and Tetric flow(p>0.05). 3. The microleakage of Vitrebond and Tetric flow used as liner showed no statistically significant difference(p>0.05).

• Journal of Conservation Science
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• v.26 no.4
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• pp.429-436
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• 2010

Dyestuffs extracted from fifteen kinds of natural dyeing materials were researched on their antimicrobial performance against 3 kinds of bacteria and 2 kinds of fungi in order to develop conservation/storage materials of traditional and natural dyed papers. The three types of mordants were evaluated by using the same method and then mixed with the dyestuffs to research their antimicrobial performance. With those results, dyed paper was made by mixing mordants with 9 kinds of dyestuffs with excellent antimicrobial performance. Among the dyed papers, Cotinus coggygria, Coptis chinensis, Phellodendri amurense, Rhus javanica and Acer ginnala multiple mordant papers were found to have an antibacterial quality against fungi, while, in the insect repellent experiment using termites, Coptis chinensis and Phellodendri amurense dyed papers were found to have insect repellent qualities. Also, with regard to the research result about the affect of dyeing paper on other materials like metal, Coptis chinensis have relatively stable qualities. Also, the three types of dyeed paper by Cotinus coggygria, Coptis chinensis and Phellodendri amurense, were found to have a tendency to remove harmful gases. Not only can these dyed papers be used for making storage box for cultural properties to prevent various organic artifacts from bio-damaging, but they can also be utilized as functional finishing materials in various spaces.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.599-605
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• 2004

기존의 구축된 GIS 컴포넌트 혹은 개발 중이거나 향후개발을 목표로 설계단계에 있는 컴포넌트들의 최종 목표는 재사용성과 상호운용성의 가능성 여부이다. 하지만 컴포넌트 개발에 있어 시스템 개발환경의 다양성으로 인하여 그 재활용성은 생각만큼 쉬운 작업이 아니며, 특히 공간정보를 다루고 있는 GIS(Geographic Information System)분야에서의 GIS 컴포넌트 재활용은 전 세계의 산재한 각 데이터형의 포맷, 개발 환경, 운영환경을 고려하여 볼 때 시급한 일임에도 불구하고 그에 대한 노력이 상당히 미진한 실 정 이 다. 본 논문에서는 GIS 애플리케이션을 보다 효율적이고 유용하게 개발하기 위하여 GIS 컴포넌트의 개발과 관리에 이르는 전 과정을 관리 감독할 수 있는 COGIS(Component Oriented Geographic Information System)을 제안하고, COGIS 프로세스의 가이드라인이며 GIS 컴포넌트의 기능적인 면을 정의하기 위한 GCA(GIS based Component Architecture) 아키텍처를 제안하였다. 아울러 GIS 컴포넌트의 메타데이터를 분류 및 정의하여 GIS 컴포넌트의 비 기능적면을 제시하고 이를 이용하여 웹 기반 GIS 컴포넌트 등록/검색 에이전트 시스템을 개발하였으며 기존 GIS 컴포넌트 재사용 및 확장, 신규 컴포넌트의 등록, 검색이 가능하도록 한다. 사례연구로 웹 상에서 산불 발생 위험지수 표출을 위한 GIS 공간 분포도 작성이 쉽게 이루어지도록 2FDRV.avx와 2FDRC.exe 컴포넌트를 개발하였으며, COGIS 프로세스의 컴포넌트 관리방법을 통하여 여러 관련 컴포넌트를 조합함으로써 웹 기반 산불위험지수예보시스템을 구축하였다.입력 근거의 확보’, ‘갱신주체별 역할의 정의 및 유지관리 기준의 설정’, ‘분야별업무 특성을 고려한 관련 기준의 마련 및 타 시스템과 연계되는 항목을 고려한 절차 정의’ 등에 대한 다양한 접근을 시도하였다. 본 연구에서 제시하는 유지관리 모델을 기반으로 각 지자체별로 적절한 컨설팅이 진행되고 이에 따라 담당자의 실천이 이루어진다면 지자체 GIS의 투자대비 효과에 대한 기대는 이상이 아닌 현실로 다가오게 될 것이다.가오게 될 것이다. 동일하게 25%의 소유권을 가지고 있다. ？스굴 시추사업은 2008년까지 수행될 계획이며, 시추작업은 2005년까지 완료될 계획이다. 연구 진행과 관련하여, 공동연구의 명분을 높이고 분석의 효율성을 높이기 위해서 시료채취 및 기초자료 획득은 4개국의 연구원이 모여 공동으로 수행한 후의 결과물을 서로 공유하고, 자세한 전문분야 연구는 각 국의 대표기관이 독립적으로 수행하는 방식을 택하였다 ？스굴에 대한 제1차 시추작업은 2004년 3월 말에 실시하였다. 시추작업 결과, 약 80m의 시추 코아가 성공적으로 회수되어 현재 러시아 이르쿠츠크 지구화학연구소에 보관중이다. 이 시추코아는 2004년 8월 중순경에 4개국 연구팀원들에 의해 공동으로 기재된 후에 분할될 계획이다. 분할된 시료는 국내로 운반되어 다양한 전문분야별 연구에 이용될 것이다. 한편, 제2차 시추작업은 2004년 12월에서 2005년 2월 사이에 실시될 계획이다. 수백만년에 이르는 장기간에 걸쳐 지구환경변화 기록이 보존되어 있는 ？스굴호에 대한 시추사업은 후기 신생대 동안 유라시아 대륙 중부에서 일어난 지구환경 및 기후변화를 이해함과 동시에 이러한 변화가 육상생태계 및 지표지질환경에 미친 영향을 이해하는데 크게 기여할 것이다.

• Journal of Conservation Science
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• v.36 no.6
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• pp.541-548
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• 2020

There is a growing demand for natural materials to replace adhesives based on volatile organic compounds (VOCs). However, the exclusion of VOCs from the manufacturing process leads to difficulties in manufacturing, and reduction in productivity and preservability. In this paper, we report the manufacture of natural bioadhesives using the carrageenan component of seaweed. λ-carrageenan, isolated from the extracted total carrageenan, was used to prepare a highly stable adhesive for paper. The resulting composition was 52.0 ± 1.0% λ-carrageenan, 30.5 ± 0.5% Polyvinylpyrrolidone, 1.0 ± 0.05% ethylhexylglycerin, 1.5 ± 0.05% glycerin, 13.5 ± 0.5% dextrine, and 0.6 ± 0.05% food-grade antifoam emulsion. The viscosity was found to be 1.13 ± 0.07 × 105 cP (25℃), UV degradation occurred at pH6.22, drying rate was 15min, △b^* was -10.79, and △E^* ab was 8.18. The bioadhesive showed an excellent adhesion strength of 44.63 kgf/cm². Thus this adhesive showed excellent fungal resistance and good adhesive persistence, without the presence of total volatile organic compounds (TVOC), formaldehyde (HCHO), and heavy metals.

• Economic and Environmental Geology
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• v.56 no.2
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• pp.201-215
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• 2023

In the stone-lined tombs from Cheongyang Rokpyeong-ri site, several stone-lined tombs corresponding to the Three Kingdoms Period, Unified Silla Period and Goryeo Dynasty were excavated. In this study, the stone properties of petrological, mineralogical and geochemical characteristics from 15 stone-lined tombs were analyzed, the rock species and occupation rate were reviewed, also the provenance area was interpreted. There are five types of rocks used as members of the tombs, including black sandstone, greywacke, slate, conglomerate and gneiss. As a result of magnetic susceptibilities, the rocks of the tombs and presumed provenance are all shown in the same range, and the similarity between the tombs and the source area is high in geochemical behavior characteristics. The stone properties of the tombs are the same as the presumed provenance rocks and is distributed within a 500m around the bedrock of the tombs in the excavation site, so it seems that self-sufficiency was possible on the site without a special procurement system. These stones are interpreted to have been constructed through some trimming without any special technique, but some stone tombs have been confirmed to used homogeneous black sandstone at the bottom of the tombs, so it is believed that there were artificial selection of stones.

• Korean Journal of Heritage: History & Science
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• v.57 no.3
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• pp.70-88
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• 2024

Syenite is the name of a rock that has been used since ancient Roman period, but it is not widely distributed worldwide, and cases of its use as a material for Korean stone cultural heritages are very rare. However, the Three-story Stone Pagoda in Beomhak-ri of Sancheong, is composed of syenite, and each stone property has very similar rock phases, mineral compositions, grain sizes, colors and magnetic susceptibilities, indicating that they are all stones of the same rock series. Outcrops of syenite are relative widely distributed in the Beomhak-ri area, and it was mined for use as building stones until recently. This rock is almost identical in overall colors, occurrences, and mineralogical and petrological characteristics to that of the stone pagoda, and the geochemical evolution trends of the rocks are also very similar. In addition, numerous quarrying traces were identified in the same rock around the Beomhaksaji Temple site. In this way, the original stone properties of the Beomhak-ri Stone Pagoda were determined to be syenite because precise petrological and geochemical analysis and provenance interpretation was possible, the syenite was distributed around the temple site, and ancient quarrying traces were scattered in the same rocks. Therefore, it can be interpreted that the Beomhak-ri Stone Pagoda was processed and constructed using self-sufficient stone materials from the temple site area.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.842-846
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• 2016

It's possible for a human to breathe under water, but the amount of dissolved oxygen in the water is small and a large amount of water is necessary to obtain sufficient dissolved oxygen from water. So, large separation system with large water pumps, having large surface areas, and large battery sources are needed. Exhalation gases are used to solve this problem. Theses gases contain some oxygen, nitrogen, and carbon dioxide; they contain less oxygen and more carbon dioxide compared to air. Therefore, reduction of the amount of carbon dioxide is necessary. If exhalation gases are employed appropriately, the separation device can be made more compact. Inlet water mixed with exhalation gases is supplied into the separation device, and dissolved gases are separated from the mixed water as it passes through the device. The inlet part of a typical separation system with a water delivery pump before the membrane module has more than one atmosphere. Hence, a compressor is used to mix the exhalation gases. In this study, the pressure at the inlet due to the use of a suction pump after the membrane module was less than one atmosphere; hence, compressors were not required. Separation characteristics were studied using a separation device without a compressor. The use of exhalation gases led to an increase in the amount of dissolved gases being separated. As the amount of inlet exhalation gases was increased, the separation of dissolved gases was increased as well.

• Conservation Science in Museum
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• v.29
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• pp.81-98
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• 2023

This study was conducted to examine the effect of the light source for the media facade of the 10-story Gyeongcheonsa Stone Pagoda on the pagoda's restoration materials. To restore the pagoda, two types of epoxy resin-L-30, Araldite (AW106, and HV953U)-were used, and the photostability of the restoration materials and the acceptable lighting irradiation time were estimated through accelerated aging experiments of the restoration specimens. Six types of specimens were used in this process: a specimen painted with blue and yellow pigments for each resin type, and an unpainted specimen. Among them, the ΔE of the unpainted specimens (BA) of Araldite AW106 and HV953U was the highest of 4.66, and the acceptable light irradiation time was about 130,000 hours if the change rate of ΔE is limited to about 1. It was confirmed that the BA specimens were losing their characteristics due to light, as their reflectance and transmittance increased and the absorbance decreased, making them more transparent than their original color. It was found that the painted specimens had a low change rate of ΔE, with insignificant changes in their reflectance, transmittance and absorbance. Therefore, the use of pigments with high photostability provides more restoration materials options.

• Proceedings of the Korea Contents Association Conference
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• 2006.11a
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• pp.218-222
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• 2006

In making 3D animation with digital technology, it is necessary to increase productivity and reusability by managing production pipeline systematically through standardization of animation content. For this purpose, we try to develop the animation content management system that can manage all kind of information on the production pipeline, based on SCORM of e-teaming by considering production, publication and re-editing. A scene as the unit of visual semantics is standardize into an object that contains meta-data of place, cast, weather, season, time and viewpoint about the scene. The meta-data of content includes a lot of information of copyright, publication, description, etc, so that it plays an important role on the management and the publication. If an effective management system of meta-data such as ontology will be implemented, it is possible to search multimedia contents powerfully. Hence, it will bring on production and publication of UCC. Using the meta-data of content object, user and producer can easily search and reuse the contents. Hence, they can choose the contents object according to their preference and reproduce their own creative animation by reorganizing and packaging the selected objects.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.329-334
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• 2005

The use of Polymer Concrete (PC) is growing very rapidly in many structural and construction applications such as box culverts, hazardous waste containers, trench lines, floor drains and the repair and overlay of damaged cement concrete surfaces in pavements, bridges, etc. However, PC has a defect economically because resin which be used for binder is expensive. Therefore the latest research is being progressed to replace existing resin with new resin which can reduce the high cost. Here, Polymer concrete using the recycled PET(polyethylene terephthalate) has some merits such as decrease of environmental destruction, decrease of environmental pollution and development of new construction materials. The variables of this study are amount of resin, curing condition and maximum size of coarse aggregate to find out mechanic properties of this. Stress-strain curve was obtained using MTS equipment by strain control. The results indicated that modulus of elasticity was increased gradually in an ascending branch of curve, as an increase of resin content. Compressive strength was the highest for resin content of $13\%$. And Compressive strength was increased as maximum size of coarse aggregate increases. The strain at maximum stress increases with an increase of resin content and size of coarse aggregate. For the descending branch of stress-strain curve the brittle fracture was decreased when it was cured at the room temperature compared to high temperature.