• Title/Summary/Keyword: Crafts

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Study on the Improvement of Inter-laminar Bonding Strength of Carbon/Epoxy Composite Structures (Carbon/Epoxy 복합재료 구조물의 층간강도 향상 연구)

  • Choi Jaeho;Song Heung-Sub;Park In-Seo;Park Seung-Bum;Hwang Byung-Sun
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2004.04a
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    • pp.161-164
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    • 2004
  • In these days, composite materials are applied to the military field like parts of air crafts, rockets, ammunitions and so on. As high pressure is loaded on the composite body, however, cracks or delamination phenomena can be occurred between layers of laminate. These cracks or delamination usually cause a deterioration of mechanical properties under the complicated loads. In this study, methods for improvement of the inter-laminar bonding strength of thick carbon/epoxy composite structures are suggested and discussed in terms of segment bending test.

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Estimation of WIGs' Take-off State Based on Planing Theory (활주선의 정상 활주 상태 모델을 이용한 WIG선의 이수 상태 추정)

  • Yeo, Dong-Jin;Yoon, Hyeon-Kyu;Lee, Chang-Min
    • Journal of the Society of Naval Architects of Korea
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    • v.44 no.5
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    • pp.534-541
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    • 2007
  • This paper suggests the mathematical method for the estimation of the required engine output for WIG crafts. The engine size of a WIG craft Is a key parameter in the design stage, because WIGs should overcome the hump drag during the take-off. Therefore, it is very important for a WIG designer to estimate required power and state change during take-off. The mathematical method was developed based on the steady planing state model of a planing boat. Through numerical calculations on various take-off states, it was found that the suggested method could give reasonable estimation of required power and state change during take-off.

An Improved Synthesis of Methyl p-Hydroxyphenylalkanoates

  • Choi, Hong-Dae;Kowak, Yong-Sil;Geum, Dak-Hyun;Son, Byeng-Wha
    • Archives of Pharmacal Research
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    • v.17 no.3
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    • pp.190-193
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    • 1994
  • Friedel-Crafts reaction isopropoxybenzene with methyl $\alpha$-chloro-$\alpha$-(maethylthio)acetate 1 afforded methyl $\alpha$-methylthio-p-isopropoxyphenylacetate 2d, which was readily converted into methyl p-isopropoxyphenylacetate 3 by reductive desulfurization with zinc dust in acetic acid. Methylation of 3 with sodium hydride and methyl iodide gave methyl $\alpha$-(p-isopropoxyphenyl)propionate 5. Methyl p-hydroxyphenylakanoates (4,6), useful intermediates for some medicines, were easily prepared by treatment of 3 and 5 with titanium tetrachloride, respectively.

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On the impact hydrodynamic load on the bottom of high-speed small craft (고속정(高速艇)의 선저(船底)에 작용(作用)하는 충격하중(衝擊荷重)의 추정(推定))

  • S.J.,Yim;J.G.,Shin
    • Bulletin of the Society of Naval Architects of Korea
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    • v.15 no.3
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    • pp.1-7
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    • 1978
  • The dynamic pressures on the bottom of high speed small crafts are studied. Using the dynamic load factor the dynamic pressure can be replaced by equivalent static pressure. Assuming that (1) the system is undamped with a single degree of freedom and (2) the load is applied triangularly, we obtained the max, value of the dynamic load factor of 1.455. We believe that this method could provide a guide to the designer who has no data on the craft in the preliminary structural design stage.

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The Professionalism and Enlightenment of Pierre Fauchard, a scholar of 18th century (임상가를 위한 특집 1 - 18세기 피에르포샤르의 '전문가주의'와 계몽주의)

  • Lee, Jue-Yeon
    • The Journal of the Korean dental association
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    • v.52 no.11
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    • pp.656-669
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    • 2014
  • This literature considers Pierre Fauchard's exploits under historical context of the enlightenment movement and development of the surgery during 18th century in France. <치과의사 Le Chirurgien Dentiste, ou Traite des dents>, a vast collection of the former and contemporary dental knowledge, technologies, and skills, established Modern Dentistry. To emphasize the professionality of dental treatment and actions involving it, Fauchard replaces the title 'dental expert' with 'stomatologist, or Le Chirurgien Dentiste' As professionalism tried to contribute to the public interest by sharing dental knowledge and technolgies, it had become a model for the dentists. Moreover, the professionalism has been accepted as an important value throughout the manufacture crafts era and the modern capitalist industrial society. Also the principles of liberty, equality, and tolerance founded during enlightenment movement, which is based on empirical positivism and rational reason, has become the legal basis of modern nations. In order to resolve the contradiction or conflict between 'liberty and equality' by 'tolerance for the public benefit', Korean dentists need develop professionalism.

양자계산을 이용한 Phenyl Alanine Layase (PAL)의 메커니즘 연구

  • Kim, Seong-Han
    • Proceeding of EDISON Challenge
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    • 2013.04a
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    • pp.203-204
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    • 2013
  • Phenylalanine Ammonia Lyase (PAL)는 phenylalanine의 산성도가 더 큰 ammonium hydrogen 과는 반응하지 않고 그것의 nonacidic ${\beta}$ proton을 제거하는 역할을 한다. Phenylalanine은 electrophilic 그룹을 갖고 있으며 지난 30 여년 동안 phenylalanine의 electrophilic 그룹이 PAL의 반응 기작에 중요한 역할을 한다고 믿어왔다. 그러나 최근 X-ray와 UV spectroscopy를 통하여 상당히 electrophilic 한 5-methylene-3,5-dihydroimidazol-4-one (MIO) 그룹이 발견되었다. 이전의 연구들은 실험을 통하여 MIO와 관련된 electrophile에 의한 Friedel-Crafts Attack 메커니즘과 electrophile에 대한 nucleophilic addition 메커니즘을 제시하였으며, 본 연구진은 양자계산을 통하여 두 가지 메커니즘의 에너지 차이를 살펴봄으로써 더욱 합리적인 메커니즘을 제시, 규명하고자 한다. 본 연구에서는 특히 electrophile에 대한 nucleophilic addition 메커니즘에 대하여 양자계산을 이용하여 반응물, 생성물, 전이상태의 분자 구조를 제시하고 반응이 일어나는데 필요한 에너지를 계산하고자 한다.

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Wharton Esherick: as a Pioneer of Studio Furniture Movement In the United States (미국 스튜디오퍼니쳐 운동에서 와튼 에쉬릭(1887-1970)의 선구자적 역할에 관한 연구)

  • 김명태;김정호;김성아
    • Journal of the Korea Furniture Society
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    • v.14 no.2
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    • pp.53-61
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    • 2003
  • Wharton Esherick (1887-1970) is the pioneer of the Studio Furniture movement which was emerging after the Second World War in the United States. As Esherick began to work on his studio at Paoli, Pennsylvania from 1926, he became enormously influential in the Stuido Furniture movement until his death in 1972. He was connecting the English Arts and Crafts ideal to the post-war craft revival. As the work of William Morris did, in the period of consumerism Esherick's furniture gave a chance to purchase unique furniture to people who wanted a different taste. Not only his furniture is unique and hand-crafted also has sculptural quality which made his followers to see furniture as a different possibilities. His work was influential to the people who followed him after the war such as Arthur Carpenter, Wendell Castle, and Sam Maloof. In the roots of the craft revival, it is hard to underestimate the contribution of Esherick's notion of sculptural furniture.

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A Study on the Background of Social Design Appearance (사회적 디자인(Social Design)의 등장 배경에 관한 연구)

  • Kang, Hyundae;Hong, Sunki
    • Journal of the Korea Furniture Society
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    • v.23 no.4
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    • pp.425-434
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    • 2012
  • The concept of humanity is considered as the common issue of various areas in the $21^{st}$ century. The diverse issues such as social design, social enterprise, and ethical consumption, etc., actually involves in the humanity. The unique aspect is that they focus on the disadvantaged group and want to do something for their severe situation in spite of the economic recession all the world faced. This paper shows how the social design appeared as a paradigm of the $21^{st}$ century design on the historical consideration, and tries to prove that the social design is not a new trend but the subtle movement that begun from $19^{th}$ century.

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Spread of Bamboo stands in the Kinki Region

  • Koizumi, Keigo;Tanimoto, Chikaosa;Piao, Chunze
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.441-443
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    • 2003
  • The Bamboo stands, which had been planted for agricultural uses, have been spreading from fields to hills and mountains beyond farmers’ expectation over the last 50 years. Bamboo stands yield bamboo shoots to be served as a vegetable dish (‘takenoko in Japanese’) every spring, and supply materials for bamboo crafts in various ways. Now, as bamboo products have lost their social demand, bamboo stands has been gradually abandoned. This has resulted in the wild and unfavorable spread of bamboo stands in many regions over the western half of Japan. This paper illustrates the unfavorable spread of bamboo stands regionally in the southern Kyoto from 1985 to 1999 and the Yamashiro area from 1948 to 2000 through the observation of satellite images and aerial photographs.

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Synthesis of 2-Aryl-5-benzoxazolepropionic Acid Derivatives as Antiinflammatory Agent (항염증제로서 2-아릴-5-벤즈옥사졸프로피온산 유도체의 합성)

  • Choi, Hong-Dae;Kowak, Yong-Sil;Geum, Dek-Hyun;Son, Byeng-Wha
    • YAKHAK HOEJI
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    • v.38 no.5
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    • pp.504-510
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    • 1994
  • A facile synthesis of 2-aryl-5-benzoxazolepropionic acid derivatives(1 0a-d), which are potent antiinflammatory agent, is reported. Methyl ${\alpha}$-(p-hydroxyphenyl)propionate(5) was prepared from Friedel-Crafts reaction of isopropoxy benzene with methyl ${\alpha}$-chloro-${\alpha}$-(methylthio) acetate(1), followed by desulfurization, methylation and clevage of ether bond. Compounds(10a-d) were made from(5) by a sequence of nitration, reduction, formation of benzoxazole ring, and hydrolysis in good yields, respectively.

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