• 제목/요약/키워드: material processing

검색결과 3,283건 처리시간 0.035초

피부로 침투된 양자점 나노입자의 분포와 전자현미경 분석 시 발견되는 오스뮴산 결합물과의 구분 (Distribution of the Quantum Dot Nano-particles that Penetrate Skin and Distinction of Combined Osmium Tetroxide in Electron Microscopic Analysis)

  • 최기주;박상용;이정민;신헌섭;양정은;이돈길;;이태후
    • Applied Microscopy
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    • 제42권1호
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    • pp.1-7
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    • 2012
  • 나노입자의 가능성은 의생물학 분야의 연구자들에 의해 열띤 토론이 되어지고 있다. 우리는 일종의 추적자인 양자점(quantum dots)을 이용하여 피부로 침투된 나노입자의 분포를 전자현미경으로 확인하는 과정에서 나타나는 문제점과 이를 해결하기 위한 방법을 제안해 보고자 하였다. 나노입자는 피부의 각질층과 모공을 통한 일부 피지세포 내부까지 침투되는 것을 확인하였다. 이 과정에서 오스뮴산이 세포 내 지방산과의 결합에 의해 나노입자 형태의 축적물이 생성되는 것을 확인할 수 있었고, 이것은 의도한 나노입자(양자점)의 분포를 확인하는데 간섭을 주는 요인이 되는 문제점을 발견하였다. 이를 해결하기 위해, 양자점과 오스뮴산을 달리 처리하는 방법을 통하여 각각의 사진에서 나타나는 나노입자의 진위 여부를 비교하므로 의도한 나노입자의 정확한 분포를 확인할 수 있었다. 이러한 결과는 의생물 분야에서 생체내 나노입자의 분포를 확인하기 위한 연구 시 오차를 감소시키고, 보다 정확한 분석을 제공할 수 있을 것으로 기대해 본다.

냉간 단조용 금형 수명 및 단조품 품질 향상을 위한 금형 특성 연구 (Characteristics of tools for improving the tool life and forged product on cold forging)

  • 이영선;권용남;권용철;이정환;최석탁
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2006년도 춘계학술대회 논문집
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    • pp.125-126
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    • 2006
  • The characteristics of the tool system give many effects into the costs and qualities for the finished components. Therefore, a tool life is one of the important issues on cold forging industry. However, since variables related with tool life are many complicated, the studies for solution should be investigated by the systematic research approach. In this study, heat-treatment of tool material is investigated to improve the tool life. Deep cryogenic treatment of tool steel is very efficient to improve the wear resistance due to the fine carbide. And, it is investigated that the shape and dimension of tool give effect into both tool life and quality of forged product.

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전자기장을 이용한 결정립 제어 소재 공정 기술 (The Technology of Material Processing for Gram Size Control by Electromagnetic Stirring)

  • 정용식;서판기;고재홍;강충길
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2004년도 춘계학술대회 논문집
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    • pp.254-258
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    • 2004
  • Actual trends in automotive industry lead to an increase use of lightweight structures imposing the need fur high strength aluminum alloys with complex shape. In the electromagnetic stirring process, it has many merits which are the exact control ability about material processing and a good point of the protection of environment comparison with the mechanical stirring. The interface of cells consisting of primary particle formed by the electromagnetic stirring due to particle regrowth during cooling the alloy. By electromagnetic stirring process, the microstructure of material has a good point, also it can control the material processing exactly.

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마찰교반처리법을 이용한 복합재료 제조의 최근 동향 (Recent Trends in the Manufacture of Composites by Friction Stir Processing)

  • 정용하;홍성태;서호철
    • Journal of Welding and Joining
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    • 제30권5호
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    • pp.16-21
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    • 2012
  • In various manufacturing industries including automotive industries, the use of lightweight materials is rapidly increasing. In the use of lightweight materials, it is obvious that enhancing their mechanical or material properties without significant weight increase is extremely beneficial. One method to enhance material properties of a lightweight material while maintaining its light weight is fabricating metal matrix composites (MMC) by adding reinforcements to the material. In the present study, recent trends in the manufacture of MMC by friction stir processing are briefly reviewed.

변형 공정지도를 활용한 A350 LF2 합금의 최적성형 조건설계에 대한 연구 (Optimum forming design of A350 LF2 alloy using the deformation processing map)

  • 정은정;염종택;김정한;이동근;박노광
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2006년도 춘계학술대회 논문집
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    • pp.168-171
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    • 2006
  • Hot deformation behavior of A350 LF2 alloy was characterized by compression tests in the temperature range of 800-$1250^{\circ}C$ and the strain rate range of $0.001-10s^{-1}$. The microstructural evolution during hot compression was investigated and deformation mechanisms were analyzed by constructing processing map. Processing maps were generated using the dynamic material model (DMM). The combination of dynamic material model and Ziegler's instability criterion was applied to predict an optimum condition and unstable regions for hot forming.

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레이저 가공기술을 이용한 도시철도차량 제작 기술 개선에 대한 고찰 (A Study of the Production Technique Improvement for EMU Using. Laser Material Processing)

  • 정종덕;김원경;홍용기;편장식
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 추계학술대회 논문집(III)
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    • pp.406-411
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    • 2003
  • This paper deals with the effect of laser material processing on the EMU production technique. Material processing with lasers takes advantage of all the characteristics of laser light. The high energy density and directionality achieved with lasers permits strong localized heat- or photo-treatment of materials with spatial resolution below one micrometer. The pulsed and mono-chromatic light allows the control of depth of heat treatment or selective excitation. The laser beam can be moved to process large areas, is a sterile tool and is no subject to wear and tear. Using laser processing have taken more interests in EMU production for improving the rigidity, weight reduction, crash durability, and cost savings so that their application to auto-bodies has been increased.

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박막 다이아몬드 필름의 후처리 공정법에 대한 고찰 (Review on Post-Processing of Diamond Thin Film Semiconductor)

  • 이헌택;이한영;황운택
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 추계학술대회 논문집
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    • pp.253-256
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    • 1995
  • This paper reviewed the methods about cost-processing of diamond stone and thin film. Five different crises of annealing conditions have been discussed with the electrical properties of doping and implantation.

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Face Detection Using Shapes and Colors in Various Backgrounds

  • Lee, Chang-Hyun;Lee, Hyun-Ji;Lee, Seung-Hyun;Oh, Joon-Taek;Park, Seung-Bo
    • 한국컴퓨터정보학회논문지
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    • 제26권7호
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    • pp.19-27
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    • 2021
  • 본 논문에서는 영상 속 인물을 탐지하고 얼굴 영역을 검출하는 방법을 제안하며, 이 방법은 2가지 작업으로 구성한다. 첫째, 서로 다른 두 명의 인물을 구분하여 프레임 내 인물의 얼굴 위치를 탐지한다. 빠른 탐지를 위해 영상 내 물체를 실시간으로 검출하는 YOLO(You Only Look Once)를 이용하여 얼굴의 위치를 탐지하고 객체탐지상자로 나타낸다. 둘째, 객체탐지상자를 바탕으로 정확한 얼굴 면적을 검출하기 위해 3가지 영상처리 방법을 제시한다. 각 방법은 검출 도형으로 추정한 영역에서 추출한 HSV 값을 이용하여 인물의 얼굴 영역을 검출하였으며 검출 도형의 크기와 모양을 바꾸어 각 방법의 정확도를 비교하였다. 각 얼굴 검출 방법은 신뢰성 검증을 위해 비교 데이터와 영상처리 데이터로 비교 및 분석하였다. 그 결과 원형, 직사각형, 분할 직사각형 방법 중 분할된 직사각형 방법을 사용했을 때 87%로 가장 높은 정확도를 달성하였다.

Challenges in Carbon/Carbon Composites Technologies

  • Dhami, T.L.;Bahl, O.P.
    • Carbon letters
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    • 제6권3호
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    • pp.148-157
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    • 2005
  • Carbon/Carbon Composites due to their far superior thermo-mechanical properties are used in a number of demanding applications. However, the material still is used only in specific high tech applications with few exceptions in general industrial applications. The material is extremely expensive and the major challenge is to reduce its cost. Various innovative processing routes are outlined to reduce the cost of processing.

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RAPD Pattern of Ginseng(Panax ginseng C.A. Meyer) Lines Containing High Level of Ginsenoside

  • Kang, Tae-Jin;Kim, Se-Young;Rho, Yeong-Deok;Deok-Chun
    • Plant Resources
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    • 제6권3호
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    • pp.170-174
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    • 2003
  • The important component for medical effect in ginseng is ginsenoside. Korea Ginseng & Tobacco Research Institute contains approximately 200 lines produced by inbred selection. It is assumed that ginseng lines containing high level of ginsenoside should be included in those lines. Besides, new breeding methods such as cell line selection in vitro and hairy root were recently developed. Therefore, this study was carried out to detect genes related to ginsenoside, and to use it for selection marker to select and distribute lines containing high level of ginsenoside. DNA was extracted from both ginseng roots and hairy roots, and the difference between the line containing high ginsenoside(KG101) and normal ginsenoside(KG103) were analysed. As a result, 28 out of 36 primers showed bands, and many primers showed band difference between ginseng lines. It is considered that the bands should be analysed using DNA sequence comparison to check if those are related to ginsenoside. In case of hairy roots of ginseng, almost no differences were found between two lines.

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