• Title/Summary/Keyword: secondary materials

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The Orientation Comparison of the Primary and Secondary Beads Grain by EBSD (EBSD를 이용한 1, 2차 용융흔 결정립의 방위 비교 분석)

  • Park, Kwang-Muk;Bang, Sun-Bae;Yang, Sung-Chae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.30 no.11
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    • pp.728-733
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    • 2017
  • Herein, for the quantitative analysis of the arc beads related to electric fire, we used electron backscatter diffraction (EBSD), a measuring device for grain orientation of materials, we compared and analyzed the surface texture of primary and secondary beads according to the difference in cooling rate at ambient temperature. This analysis revealed that the primary beads showed similar distribution at both low and high angles, while the secondary beads showed a higher distribution at low angles than at high angles. Thus, EBSD can be used for quantitative analysis of the beads and can be applied to identify beads in the future.

Aesthetic Considerations after Free Flap Reconstruction

  • Lee, Sang Shin;Kim, Eun Key
    • Archives of Reconstructive Microsurgery
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    • v.23 no.1
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    • pp.8-12
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    • 2014
  • Purpose: The success rate of free flap operation has shown a recent increase. Especially for breast reconstructive patients, aesthetic results are considered a necessity. However, for patients who underwent reconstruction in parts of the body other than breast, for example, head and neck, lower and upper extremities, aesthetic considerations are underscored. Nowadays, however, aesthetic standpoint toward these patients is changing. Materials and Methods: We conducted a retrospective review of 8 patients who underwent secondary procedures after free flap surgery from March of 2011 to April of 2014. Results: Secondary refinement was a safe and less time-consuming technique for maximizing the function and aesthetic appearance for the patient. Conclusion: Appearance has become increasingly important with regard to function and quality of life. Therefore, for free flap reconstructive patients, secondary refinements may be considered in order to change the shape and contour. The secondary refinements are critical to the final result and must be a planned part of the entire reconstructive sequence.

Effect of Surface Treatment on Adhesive Bonding Strengh of Composite Material for Cryogenic Application (극저온용 복합재료의 접착부 강도에 미치는 표면처리 효과에 대한 연구)

  • Ahn, Myoung-Ho;So, Yong-Shin;Park, Dong-Hwan
    • Proceedings of the KWS Conference
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    • 2010.05a
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    • pp.28-28
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    • 2010
  • The secondary barrier of cargo containment for membrane LNG tank is composed of composite materials such as rigid triplex (rigid secondary barrier, RSB) and flexible triplex (flexible secondary barrier, FSB). RSB and FSB are adhered to each other using an epoxy adherent and the quality of the secondary barrier depends on the bonding strength between them. The bonding strength between RSB and FSB is greatly influenced by the surface condition of RSB prior to joining. In this study, the effect of surface condition prior to joining on the joint strength and the fracture mode occurred between RSB and FSB have been examined in order to establish a proper surface treatment method for improving the bonding strength at the temperature of $-170^{\circ}C$.

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Analysis on Power Consumption and Accumulated Energy According to Resistance of Superconducting Element and Winding Current of Transformer Type SFCL Using Double Quench (이중 ?치를 이용한 변압기형 초전도 한류기의 권선전류와 초전도소자 저항에 따른 전력소모 및 누적에너지 분석)

  • Han, Tae-Hee;Lim, Sung-Hun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.29 no.10
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    • pp.630-634
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    • 2016
  • In this paper, we analyzed the power consumption and the accumulated energy in HTSC (high-TC superconducting elements) according to the resistance of HTSC element and the winding current of transformer type SFCL (superconducting fault current limiter) using double quench. For the analysis, two different inductances of the one secondary winding among two secondary windings comprising the transformer type SFCL were selected and the short-circuit tests were carried out. The consumed power and the accumulated energy in HTSC element connected into the secondary winding with larger inductance were analyzed to be larger compared to the one connected into the secondary winding with lower inductance.

Research and Development of Marine Bio-Organisms - Introduction and Its prospect -

  • Han, Sangtae;Kim, Jong-Man
    • Journal of Marine Bioscience and Biotechnology
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    • v.2 no.2
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    • pp.73-76
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    • 2007
  • A large number of natural products were worldwidely discovered from maine organisms. There are many secondary metabolites produced by maine organisms which showed very strong bio-activities and distinct bio-active mechanisms. In korea, about 350 secondary metabolites including more than 280 novel compounds have been isolated and structually defined. Many researches for developing products such as cosmetics, functional food materials, anti-fouling substances are being performed using distinct activities of marine organisms. Although the research on marine natural products has been remained at its initial or developing stage of drug development, significant progress has been made for isolation, structure determination and bioassay of secondary metabolites.

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An Analysis of the Needs of the Preservice Secondary School Teacher on Understanding of International Society and Curriculum of International Understanding (국제사회의 이해 및 국제이해교육과정에 관한 중등 예비교사들의 인식 연구)

  • Park, So-Young;Park, Jae-Kook
    • Journal of Fisheries and Marine Sciences Education
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    • v.22 no.1
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    • pp.11-24
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    • 2010
  • The purpose of this study was to analyze the needs of the preservice secondary school teacher on understanding of international society and curriculum of international understanding and to derive the implications on developing curriculum of international understanding. This study used a questionnaire survey. The results are summarized as follows. First, it seems to be necessary to develop curriculum for satisfying the higesconcerns on worldsculture of preservice secondary school teacher. Second, the curriculum of educating international understanding for preservice secondary school teacher should contain such contents as multiple cultures, multiple perspectives, global relations and instructional materials. Third, it is necessary that instructions on educating international understanding should employ experience of global culture, discussion, lecture and so on.

Secondary Science Teachers' Employment Systemin China Mainland

  • Jingjing, Luo;Xingkai, Luo
    • 한국과학교육학회:학술대회논문집
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    • 2008.08a
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    • pp.47-56
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    • 2008
  • This article presents how in China mainland a school and a school district find their science teachers. Based on studying relevant materials and years of intensive involvement in teacher education and recruitment practices the authors draw three features of the current secondary science teachers' employment system in China mainland: certification control conducted very loosely selection criteria and process vary with schools and school districts due to the remarkable difference existed among them the normal universities/colleges established originally only for secondary science teacher education still play a vital role in shaping effecting quality of teacher candidates although no one of them for a long time have focused on only doing what they were supposed to do. For further development, changes and essential reform are expected duo to the increasing promotion toward the internal quality of education and therefore high quality of teachers and teacher candidates.

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A New Method for Synthesizing Tetrazoles from Secondary Amines using Trichloroacetonitrile (이차 아민으로부터 트리클로로아세토니트릴을 사용한 테트라졸 유도체의 새로운 합성법)

  • Oh, Su-Jin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.6
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    • pp.781-787
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    • 2017
  • A new method for synthesizing the tetrazole derivatives from secondary amines through cyanation/tetrazolation has been developed. Trichloroacetonitrile is used as the cyano source to synthesize N-nitrile instead of highly toxic and expensive cyanogen bromide. In this protocol, the reaction of secondary amines with various substituents proceed smoothly, and the desired tetrazole derivatives are obtained directly in fair to high yields without isolation of intermediate cyanamides.

Vertical Vibration Analysis of a Magnetically Levitated Vehicle due to Random Track Disturbances and Dynamic Design of Its Secondary Suspensions (불규칙 궤도외란을 받는 자기부상열차의 진동해석 및 2차현가장치 동적설계)

  • Choe, Yeong-Hyu;Heo, Sin;Kim, Yu-Il
    • 연구논문집
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    • s.22
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    • pp.39-46
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    • 1992
  • A dynamic design process was proposed for the design of the secondary suspension characteristics of a magnetically levitated vehicle(MAGLEV). It is based on a ride quality-secondary stroke trade-off. For the vertical vibration analysis, a magnetically levitated vehicle was simplified as 2 d.o.f. linear model, and FRA's class-6-track irregularities were considered as exciting disturbances. The optimum value of airspring stiffness and damping coefficient for the secondary suspension of a prototype MAGLEV was determined using this proposed design process.

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