• Title/Summary/Keyword: bronze

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Theoretical Considerations on the Design of Metal Frames for Refractive Correction (시력교정용 금속테설계의 이론적고찰)

  • Kang, Hyunsik
    • Journal of Korean Ophthalmic Optics Society
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    • v.3 no.1
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    • pp.39-73
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    • 1998
  • In the 60's to 70's, frame selection was a purely mechanical consideration almost entirely dominated by the optician and his subjective judgments. Toddy the cosmetic factor is predominant. The variety of frame color, materials, and style means that the main burden of selection has passed to the customer, leaving the optician control a subtle factor often difficult to exert. Common materials include nickel silver, Hi-nickel alloy, bronze, stainless steel, gold, gold plated, gold clad, copper beryllium, titanium and sometimes aluminium. In manufacturing of metal frames with the materials, even though fashion is the stimulant of consumer demand, all the metal frame for the prescription to refractive correction should be designed correctly styled eyewear which is cosmetically pleasing, functional correct, physically comfortable, mechanically and structurally perfectible, and temperamentally acceptable.

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Analysis of Open Access Status of Domestic Author's Papers Published in International Journals: Based on Highly Cited Papers (국내연구자가 출판한 국제학술지 논문의 오픈액세스 현황 - 고피인용된 논문 중심 -)

  • Cho, Jane
    • Journal of the Korean Society for Library and Information Science
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    • v.54 no.1
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    • pp.325-341
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    • 2020
  • This study used the Unpaywall API, one of the open tools to track the OA version, to empirically identify the OA of 3,905 papers that have been published by Korean corresponding authors since 2015 in international journals. As a result, the following facts were found. First, less than 30% of papers have been open accessed, and more than half of them were bronze OA. Secondly, the archiving site of the Green OA papers was found not to be domestic but mainly subject repositories or institutional repositories of overseas universities to which co-authors belong. Third, only 19.6% of research fund granted papers were open accessed and half of them were in the medical field. In contrast to the international trends in which the OA papers showed higher citations, the analyzed OA papers showed no higher citations than the non-OA papers.

A Study on the Applicability of Corrosion Inhibitor for Outdoor Copper Alloy

  • Shin, Jeong Ah;Wi, Koang Chul
    • Journal of Conservation Science
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    • v.34 no.4
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    • pp.259-271
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    • 2018
  • Outdoor copper alloy is exposed to the atmospheric environment, accelerating corrosion progress compared with indoor copper alloy. In order to prevent corrosion, the outdoor copper alloy is coated with wax to block external corrosion factors. However, corrosion of the inside of the coating film is highly likely to continue without the internal corrosion prevention treatment. B.T.A, which is used as a copper alloy water-soluble corrosion inhibitor, has a high possibility of being harmful to the human body and is mainly used to treat excavated artifacts. This study had selected the water-soluble corrosion inhibitor, which was easier to use than the existing wax and B.T.A being used in corrosion inhibition treatment for outdoor copper alloy. A comparative study was conducted on B.T.A, which is a water-soluble corrosion inhibitor used on excavated artifacts, and $VCI^{(R)}$, $Rus^{(R)}$, and L-cys, an amino acid corrosion inhibitor, used for tin bronze test pieces. The experimental method was conducted for a certain period of time with the salt, acid, and air pollution affecting the corrosion of outdoor copper alloy. Based on experiment results, it was concluded that the best water - soluble copper alloy corrosion inhibitor in the atmospheric environment is $VCI^{(R)}$. and it could be considered to be applied in replacement of B.T.A due to its low harmfulness. In addition, $VCI^{(R)}$ is judged to serve as a corrosion inhibitor for outdoor copper alloy because it showed the best result even in the outdoor exposure test which is a real atmospheric environment.

Manufacturing Techniques of Ancient Metal Buddha Statues from Archaeological Sites in Bagan, Myanmar

  • Lee, Jae Sung;Win, Yee Yee;Lee, Bonnie;Yu, Jae Eun
    • Journal of Conservation Science
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    • v.35 no.4
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    • pp.309-316
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    • 2019
  • This study intends to identify manufacturing techniques, including casting and alloy composition, of nine metal Buddha statues excavated from archaeological sites in Bagan, Myanmar. Two Buddha statues from Pyu city state(2nd to 9th century) contain Cu-Sn alloy(including <1 wt% Fe), with different relatively high percentages of Sn(16 wt% and 25 wt%) identified from each Buddha statue, and no Pb detected. Five Buddha statues from the Bagan dynasty contain various alloy ratios of Cu-Sn(including <1 wt% Pb), Cu-Sn-Pb, and Cu-Sn-Zn-Pb. All Buddha statues appear to be fabricated by casting, as there is no evidence of other heat treatments. The silver Buddha statue manufactured in the 18th century includes >1% Cu besides silver with no additional metallic components identified. The bronze Buddha statue manufactured in the Konbaung dynasty(18th century) is of Cu-Sn-Pb alloy. The Buddha statues of Pyu was alloy of Cu-Sn without Pb including ahigh percentage of The Buddha statues of both the Bagan and Konbaung dynasties are comprised of ternary Cu-Sn-Pb alloys, with a heterogeneous distribution of lead and tin. Some of Buddha statues of the Bagan dynasty have similar alloy ratios as those of Pyu, suggesting that similar manufacturing techniques were used.

A Scientific Analysis of Archaeological Textiles and Wooden comb Excavated from Hapgang-ri, Dong-myun, Yungi-gun, Chungcheongnam-do (충남 연기군 동면 합강리 유적 출토 직물류 및 목제 빗의 과학적 분석)

  • Cho, Namchul;Kim, Woohyun;Kim, Soochul
    • Journal of Conservation Science
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    • v.30 no.4
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    • pp.329-334
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    • 2014
  • A scientific analysis of ancient textiles provides significant data to understand weaving techniques and culture of textiles in each region and charateristics of materials used at that time. In addition, species identification of waterlogged wooden objects is a scientific analysis method that allow us to verify information of relation of foreign species trade and exchange, of preferable species through kinds of wooden products, and of forest environment as well as method setting of conservation. As a result of a species analysis about historical textiles and a wooden comb in a bronze bowl that were excavated from Hapgang-ri, Dong-Myun, Yungi-gun, Chungcheongnam-do, Textile1 and Textile3 are identified as Urticacese Boehmeri nivea ; ramie, Textie2 is identified as Malvaceae Gossypium herbaceum, and a wooden comb is identified as Betulaceae Betula spp. It is expected that this result will help to make further comparative studies, identifying species of textiles and trees of ancient times.

A Study on the Possibility as a Site for Geopark in Korea: Byeonsanbando National Park (국내 지구공원 적지 가능성 연구: 변산반도 국립공원)

  • Heo, Chul-Ho
    • Journal of the Korean earth science society
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    • v.28 no.1
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    • pp.136-141
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    • 2007
  • The UNESCO`s earth science division has developed the geoparks program to recognize earth scientific heritage sites worldwide. To respond to this movement, I suggest Byeonsanbando National Park (BNP) as the first geopark in Korea and provide, at the same time, a line of evidence supporting the designation of geopark. BNP has the best qualifications with geological, geomorphological, ecological, and cultural resources. In Chaeseokgang and Jeokbyukgang, there are many geological and geomorphological resources attracting the scientific importance. In addition, BNP has a total of 844 species of wild plants and 550 species of wild animals. Cultural properties abound in BNP, including Koryo bronze bell of Naesosa and Taeungjon hall of Kaeamsa. To be designated a geopark by UNESCO, a management plan of geotourism will be required in addition to the geological, geomorphological, ecological and cultural resources, which should be prepared by the Korea National Parks Service and related local government authority. If the above-mentioned conditions are met completely, Korea would enter the global network of geoparks for the first time.

A Study on Korean Man's Head Ornaments in the Joseon Dynasty (조선시대 남자(男子)의 수식(首飾) 연구(I))

  • Chang, Sook-Whan
    • Journal of the Korea Fashion and Costume Design Association
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    • v.10 no.1
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    • pp.99-116
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    • 2008
  • This study reviewed pertinent literature and examined relics of manggon(a headband worn to hold a man's topknot hair in place), donggot(a topknot pin), and chigwan(a topknot cover). Before the modernized short hair style, wearing a gat was an important custom. Therefore, manggon, which was used to hold a man's hair in place under the gat, was considered an essential part of the man's official dress code. Donggot is a pin that held the topknot hair in place. It was a must have for a married man, like the binyeo, a lod-like hairpin, for a married woman. Unlike gwanja, it had nothing to do with official rank, but materials were of a variety of materials, including jade and gold. The structure of the donggot was studied in three parts-head, neck and body. Major forms for the head include the mushroom, bean and ball. Bullet and half-cut bullet forms were also found. Forms for the neck include straight-neck and curved-neck. A neck with a belt around a double chin was also found. Forms for the body include the tetrahedron, octahedron and cylinder. The most popular form for silver and white bronze donggot heads was the mushroom, followed by bean and pile forms. Chigwan is also called chipogwan, chichoal, choalgyesogwan, noingwan and sangtugwan. In poetry it was called chichoal, and it used to be called taegogwan in the past as well. Chigwan was so small that it managed to hold a topknot. According to confucian custom in the Joseon period, by wearing chigwan, men didn't display their bare topknot even when they didn't dress up. When they went out, they wore another official hat over the chigwan.

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Effect of Seed-layer on the Crystallization and Electric Properties of SBN60 Thin Films (SBN60 박막의 결정화 및 전기적 특성에 관한 씨앗층의 영향)

  • Jang, Jae-Hoon;Lee, Dong-Gun;Lee, Hee-Young;Jo, Sang-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.723-727
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    • 2003
  • [ $Sr_xBa_{1-x}Nb_2O_6$ ] (SBN, $0.25{\leq}x{\leq}0.75$) ceramic is a ferroelectric material with tetragonal tungsten bronze (TTB) type structure, which has a high pyroelectric coefficient and a nonlinear electro-optic coefficient value. In spite of its advantages, SBN has not been investigated well compared to other ferroelectric materials with perovskite structure. In this study, SBN thin film was manufactured by ion beam sputtering technique using the prepared SBN target in $Ar/O_2$ atmosphere. SBN30 thin film of $1000{\AA}$ was pre-deposited as a seed layer on $Pt(100)/TiO_2/SiO_2/Si$ substrate followed by SBN60 deposition up to $3000{\AA}$ in thickness. As-deposited SBN60/SBN30 layer was heat-treated at different temperatures of 650, 700, 750, and $800^{\circ}C$ in air, respectively The crystallinity and orientation behavior as well as electric properties of SBN60/SBN30 multi-layer were examined. The deposited layer was uniform and the orientation was shown primarily along (001) plane from XRD pattern. There was no difference in the crystal structure with heat-treatment temperature, but the electric properties depended on the heating temperature and was the best at $750^{\circ}C$. In electric properties of Pt/SBN60/SBN30/Pt thin film capacitor prepared, the remnant polarization (2Pr) value was $15{\mu}C/cm^2$, the coercive field (Ec) 75 kV/cm, and the dielectric constant 1075, respectively.

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The Effect of Annealing Heat Treatment by Anodic Polarization Impedance Experiments for Cu-10%Ni Alloy

  • Lee, Sung-Yul;Moon, Kyung-Man;Jeong, Jae-Hyun;Lee, Myeong-Hoon;Baek, Tae-Sil
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.5
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    • pp.536-541
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    • 2015
  • Copper has been used extensively as an electric wire or as a base material in various types of machineries owing to its good electrical and thermal conductivity and good fabricating property, as well as its good corrosion resistance compared to iron. Furthermore, the copper-nickel alloy has significant corrosion resistance in severely corrosive environments. Although, cupro-nickel alloy shows better corrosion resistance than the brass and bronze series, this alloy also corroded in severely corrosive environments, including aggressive chloride ions, dissolved oxygen, and condition of fast flowing seawater. In this study, and annealing treatment at various annealing temperatures was carried out on the cupro-nickel (Cu-10%Ni) alloy, and the effects of annealing were investigated using electrochemical methods, such as measuring the polarization and impedance behaviors under flowing seawater conditions. The corrosion resistance increased by annealing compared to non heat treatment in the absence of flowing seawater. In particular, the sample annealed at $200^{\circ}C$ exhibited the best corrosion resistance. The impedance in the presence of flowing seawater showed higher values than in the absence of flowing seawater. Furthermore, the highest impedances was observed in the sample annealed at $800^{\circ}C$, irrespective of the present of flowing seawater. Consequently, the corrosion resistance of cupro-nickel (Cu-10%Ni) alloy in a severely corrosive environment can be improved somewhat by annealing.

A Study on the Material of Furniture in Goryeo (고려시대 가구재료 연구)

  • Cho, Sook-Kyung
    • Journal of the Korea Furniture Society
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    • v.25 no.1
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    • pp.19-27
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    • 2014
  • This paper studied the materials of the furniture which the noble men used in Goryeo, based on the furniture material category of solid wood furniture, lacquerware inlaid with mother-of-pearl and hardware. As for the solid wood furniture, the wood and furniture types are inferred based on the documents. The trees used for the wood furniture were zelkova, korean willow, pine, royal paulownia, maidenhair tree, korean pine, chinese juniper and elm. The furniture types were table, chair, wooden bench, small portable table, writing table, and folding screen. As to the types of lacquerware inlaid with mother-of-pearl, most of them were hams with top, which were made of abalone shells. The features of the lacquerware inlaid with mother-of-pearl were in detail and elaborate like the pattern of the full bloomed chrysanthemum. Writing tables were also made of lacquerware as pieces of furniture. Distinctively, the mother-of-pearl furniture material was popular enough to be used even in a horse saddle. Regarding the metal feldspar used as both a practical use and decoration, there are drop handle, hinge, the front basis, and lock seen in the artifacts, which were made of cast iron, bronze, and brass. Their manufacture techniques were eojamoon, bratticing and sheet metal. Through this study of the furniture materials used in Goryeo, it seems that Goryeo furniture focused on the functions rather than on the decorations, and in turn the forms were simple and basic. The technique of mother-of-pearl, a bit elaborate one, was used in the props furniture like kitchen wares, hams, or writing talbes. Probably, the solid wood is inferred to be used in a low wooden bench, a chair, and a table based on the documents.

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