• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.4
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• pp.640-647
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• 1996

It has been found that an white precipitates at the inside surface is a common characteristics of soda-lime-silica glasses which have not undergone special surface treatments during hot weather season. In this study, the white deposits were examed using by solution method, surface analysis etc., and the dependence of weathering on the atmospheric condition was also investigated. As a results, the white precipitates on the glass surface was discorved as carbonates like $Na_2CO_3{\cdot}H_2O,CaCO_3$. Coming to atmosphere-dependence, it was shown that the glass made and stored at sea shore province had 3 times much severe weathering than that at land province.

• Conservation Science in Museum
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• v.22
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• pp.69-84
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• 2019

This study investigated the formal characteristics and chemical compositions of eighty beads excavated from a Silla tomb complex at Deokcheon-ri, Uljin in order to reveal the methods of production and the characteristics of the raw materials involved, thereby illuminating characteristics of the relics from each tomb. The beads excavated from these Silla tombs include one curved bead, one tubular bead, and 78 globular beads. Among them, the curved and tubular beads and three globular beads were identified to be made of minerals, and the remaining 75 beads are made of glass. Most of the glass beads are thought to have been produced using the drawing technique. The characteristics of the beads were classified according to their site of excavation. The globular beads from Tomb No. 34 belong to the lead-barium glass and potash glass groups, indicating that these beads were produced at a relatively earlier period in time. The glass beads excavated from the tombs in the northern portion of the complex differ in color and chemical composition from those in the southern portion, which indicates the character that each group of beads had different aspect according to site location. Considering that the excavated beads were mainly from fifth- and sixth-century tombs, it is likely that certain groups of people living around Uljin used and buried beads in their tombs. As the governance of Silla became more centralized in the sixth century, the use of beads for burial purpose appears to have come to an end in this region.

• Journal of Conservation Science
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• v.33 no.5
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• pp.331-344
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• 2017

In this study, glass beads from Osan Sucheong were classified according to color into 10 groups. Among these groups, reddish brown, bluish green, and purplish blue were identified as the main colors of glass beads based on their large quantities in Osan Sucheong. The glass beads of these main colors were then classified according to their chemical compositions and and looked at the changing process. Based on the results, reddish brown and bluish green glass beads can both be divided into five types, and purplish blue glass beads can be divided into four types. Furthermore, according to continuity of type, it was identified as the main attributes that the reddish brown beads belong to two types, whereas the bluish green and purplish blue each belong to one type. Based on a review of primary attributes, beads of these three colors were identified as soda glass and high-alumina glass. The results indicate that these beads came from a single, consistent route of origin into the region. However, it is possible that glass beads came through various routes into Osan Sucheong in the $4^{th}$ century, because many types of chemical compositions have been detected for beads from this time.

• The Journal of Engineering Research
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• v.6 no.1
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• pp.15-27
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• 2004

The first aim of mass product of glass in Automatic bottle glass industry is to decrease the cost and to increase the quality. Second, the cullet is how widely used to save the energy and reducing of ecomaterials. However the physical and chemical properties of Soda-lime glass would be come true at the lower than 2% $Al_2 O_3$. Unfortunately the $Al_2 O_3$ contents of domestic silica is greater than 4% Since small glass class than 200ml bottle is made in domestic silica the producting efficiency would be decreased due to the defect such as cord, knot, devitrite, pore etc. There are many problems such as devitrifiacation and deteriorated effect on production in glass industry became of increasing of plate glass cullet. It is tried to solve these kinds of problems using various analysing methods in this experiments.

• 월간 기계설비
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• s.285
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• pp.89-99
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• 2014

세미나를, 혹은 공연을 보면서 하늘을 볼 수 있다면? 또 전문분야인 의과학 세미나 과정을 일반인들이 밖에서 지켜볼 수 있다면? 흔히 세미나와 공연은 집중을 요하기 때문에 밀폐된 시설로 건축된다. 그런데 세미나실을 투명한 유리로 마감하여 오픈된 공간으로의 과감한 선택과 대강의실에서 하늘의 구름과 별, 그리고 채광을 한껏 받아들일 수 있도록 설계된 건물이 우리나라에 들어선다. 인류의 질병치료와 생명연장 이념으로 건립되는 차병원그룹 판교종합연구소다. 세계적인 의과학 연구소로의 발돋움은 물론 국내 의료계 발전을 위한 랜드마크로서의 의미가 큰 차병원그룹 판교종합연구소는 (주)대우건설이 시공을 총괄하고 환경이엔지(주)가 기계설비 시공을 담당하고 있다. 본지는 차병원그룹 판교종합연구소를 이달의 표지로 선정했다.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2004.05a
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• pp.202-206
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• 2004

본 연구에서는 고밀도로 백색 발광다이오드를 웨이퍼 상에 제작하기 위한 제조공정에 필요한 포토마스크를 제작하는 연구를 수행하였다. 발광다이오드 한 개의 패턴을 웨이퍼상에 연속적으로 배열하여 이를 병렬로 연결하는 금속배선을 고려하였다. AutoCAD의 DWG 파일로 캐드작업을 수행하여 이를 DXF 파일로 변환하였으며, 레이저빔으로 스켄하여 소다라임 유리판 위에 크롬을 식각함으로써 포토마스크를 제작하였다. 이는 기존에 제작된 개별칩 형태의 발광다이오드 제작공정을 집적공정화함으로써 웨이퍼상에서 전면 발광하는 조명광원의 구조를 갖는다. 또한 이를 활용하여 백색 발광다이오드 집적칩을 제작하려 한다.

• 보존과학연구
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• s.35
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• pp.5-23
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• 2014

The possibility of non-destructive inspection glass beads for verification. Conduct a comparative analysis of the Chungcheong area with glass beads excavated Age-specific characteristics of the glass beads shall be classified by region. Trace amounts of ingredients such as CaO, $Al_2O_3$ (stabilizer), MgO, the difference is negligible. $SiO_2$ (subjects), $Na_2O$ (flux) analysis and the difference between the values was greater than in the other ingredients. Composition differences occurred rough surface to a non-uniform cross-section analysis is considered. Minimize the error value, such as the surface of carbon-coated Study, there are additional requirements. Produced at the time of the social and cultural characteristics of ancient glass and important archaeological materials, and to inform the process of cultural exchange between each region in the production of glass technology era according to the level of science and technology, arts and crafts, can be identified.

• Journal of Conservation Science
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• v.7 no.1
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• pp.23-30
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• 1998

The examination of scientific analysis could give many information on the object of ancient glass. It would be allowed to understand the cultural situation and a course of inflow that the data of glass composition was classified by raw materials, technique of making, period and regional groups. Quantitative analysis conditions for SEM-EDS were set for glass and glaze on the pottery and 62 samples of glass beads excavated from Yangdong-ri remains at Kimhae were analyzed and classified. It was found that the glass beads were made of all alkali-glass. In addition, it was postulated that the potash glass was appeared from the 1st century A.D. and soda glass was appeared from the late second or early 3rd century A.D. in this region. The colors of glass were closely related to the concentration of metallic elements such as copper, iron and manganese. It was confirmed that the composition of glass beads could be classified and characterized by raw materials, color, period and regional groups.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.5
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• pp.74-81
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• 2019

This study reports the CW $CO_2$ laser scribing of soda lime glass. In this study, scribing experiments are carried out at different laser powers, scan speeds, and focal positions to investigate the effect of the process parameters on the interaction characteristics between a laser beam and glass. In particular, the interaction characteristics are analyzed and described with the input laser energy per unit length. According to the experimental results, the damage threshold for the glass surface was found to exist between 0.072 and 0.08 J/mm. The input laser energy in this region induced partial melting of the surface and grain-shaped cracks. These cracks tended to increase as the input laser energy increased. At the laser input energy larger than 1 J/mm, a huge crack propagating along the scan direction was produced, and the volume below the scribed area was fully melted. The growth of this crack finally resulted in the complete cutting of the glass at the input laser energy above 8 J/mm. It was found that both the width and depth of the scribed line increased with increasing input laser energy. For the beam focusing at the rear surface, the width of the scribed line varied irregularly. This could be ascribed to the increased asymmetry of the beam intensity distribution when the laser beam was focused at the rear surface. Under this condition, a large burr was only produced on one side of the scribed line.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.3
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• pp.103-106
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• 2022

The effect of Al₂O₃ on isokom temperatures in soda-lime glass is estimated by comparing calculated isokom temperatures using viscosity model proposed by Lakatos. Substitution of SiO₂ with Al₂O₃ by 0.5 mol% raises the isokom temperatures by 3.1, 3.3, 3.6 and 7.2℃ at the viscosity of log η = 12.3, 10, 6.6 and 1 (Pa·s), respectively. Meanwhile, replacing 0.5 mol% of CaO with Al₂O₃ raises the isokom temperatures by 1.6, 2.3, 4.1 and 17.7℃ at the viscosity of log η = 12.3, 10, 6.6 and 1 (Pa·s), respectively.