• 제목/요약/키워드: practical surface

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Recent progress of Ergonomics Studying in CRTs Design and Manufacturing

  • Wu, Mingli;Duan, Cheng
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.450-452
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    • 2004
  • This paper analyzes some important achievements in Ergonomics field in CRT industry. After introducing principal regulatory requirements for CRTs, including ISO 9241 and TCO standards, the paper indicates some theoretical research in ergonomics of the display devices, such as new contrast parameter for appraising the display devices and effects of environment on visual performance at the ergonomic. Then, as the pivot of this paper, some practical progress, in the ergonomics field in CRT manufacturing , are described, such as vacuum sputtering process for advanced CRTs, new developed wet process for getting the multi-coating layers on surface of the panel.

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연질재료의 최적 절삭조건설정에 관한 연구 (A Study on the Optimal Cutting conditions for Mild Materials)

  • 최상련
    • 한국생산제조학회지
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    • 제8권1호
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    • pp.112-118
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    • 1999
  • Aluminum alloy, which is advantageous to machining and injection, makes a great contribution to shortening in delivery time, infection cycle time and reducing expense. This study presents machining conditions for mild materials and describes the difference between theoretical and practical machined surface roughnesses affected by various machining conditions. Machining results have been evaluated and analyzed under varying machining conditions. Special properties of the mild materials have been presented by the quantitative analysis and the optimal machining condition has been proposed for the mild materials.

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피로 균열 형상 진전의 수치 모델링 기법에 관한 연구 (A Numeric Modelling Technique for the Shape Development of Fatigue Crack)

  • 한문식
    • 한국정밀공학회지
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    • 제16권2호통권95호
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    • pp.225-233
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    • 1999
  • This paper describes a versatile finite element technique which has been used to investigate of wide range of structural defects of practical importance. The procedure automatically remeshes the three-dimensional finite element model during the stages of crack growth. Problems analyzed to date include the surface cracks in leak-before-break situations, the development of quarter-elliptical corner defects, planar semi-elliptical surface defects and the fatigue growth of defects.

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압축 $SF_6$가스의 절연파괴에 대한 이론적 연구 (Theoretical Investigation of Electrical Breakdown in Compressed $SF_6$)

  • 이동인
    • 전기의세계
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    • 제27권2호
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    • pp.64-68
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    • 1978
  • By applying the streamer breamer breakdown criterion and the surface roughness factor, the effet of field distortion due to conductor surface roughness on breakdown is investigated theoretically in a uniform-field of compressed SF$_{6}$. It has been shown that the streamer constant has a significant influence on the threshold of breakdown and different shapes of protrusions do not result in different thresholds of breakdowns. Moreover, uniform-field tests can give results which apply to e-ratio coaxial-electrode systems of practical dimensions, and may offer some advantages compared with coaxial-electrode tests.s.

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분할법 구조를 갖는 반응표면 실험에서 최대경사법 수행 방법 (Carrying Out the Method of Steepest Ascent in a Response Surface Experiment with Split-Plot Structure)

  • 이종성
    • 산업기술연구
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    • 제31권A호
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    • pp.27-31
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    • 2011
  • In many industrial experiments, some practical constraints often force factors in an experiment to be much harder to change than others. Such an experiment involves randomization restrictions and it can be thought of as split-plot experiment. This paper investigates the path of steepest ascent/descent within a split-plot structure. A method is proposed for calculating the coordinates along the path.

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Transparent and Superhydrophobic Films Prepared by Polydimethylsiloxane-Coated Silica nanoparticles

  • Park, Eun Ji;Sim, Jong Ki;Jeong, Myung-Geun;Kim, Young Dok;Lim, Dong Chan
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.218-218
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    • 2013
  • We report a simple and cost-effective method to fabricate transparent superhydrophobic surface on various substrates. The surface was fabricated by coating hydrophobic PDMS (polydimethylsiloxane) film on the silica nanoparticle and subsequent fixing of the hydrophobic silica nanoparticles onto substrates. The water contact angle for the prepared surface was determined to be over $150^{\circ}$, whichindicates that the surface is highly repellent to water. The hierarchical structure and roughness of the surface were examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Additionally, transparency of the prepared surface was measured with UV-VIS spectrometer. The transmittance of the superhydrophobic surface was ~80%, which is lower than that without PDMS-coated silica by only 5 to 10%. It is also notable that the superhydrophobic surface fully recovers its original transmittance after self-cleaning process. Also the PDMS coating is stable under a wide range of pH conditions, UV radiation and salinity conditions, which is essential for the practical use. Moreover, our fabrication method is applicable in large scale production.

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표면적이 증가된 분별침전에 의한 paclitaxel의 입자 크기 감소 (Decrease in the Particle Size of Paclitaxel by Increased Surface Area Fractional Precipitation)

  • 이지연;김진현
    • 한국미생물·생명공학회지
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    • 제40권2호
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    • pp.157-162
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    • 2012
  • In this study, we have for the first time applied increased surface area fractional precipitation in order to decrease the particle size of the anticancer agent paclitaxel from plant cell cultures. When compared with the case where no surface area increasing material was employed, the addition of ion exchange resin as a surface area increasing material resulted in a considerable decrease in the size of the paclitaxel precipitate. When ion exchange resin was used, the paclitaxel particles were four to five times smaller, having less than a 20 ${\mu}m$ radius, than those obtained in the absence of ion exchange resin. This is presumably because the growth of paclitaxel particles was impeded by the addition of ion exchange resin. The size of the paclitaxel precipitate also depended on the material used to increase the surface area, a result considered to be due to differences in the affinity between the particular ion exchange resin used and the paclitaxel particles. The yield of paclitaxel was significantly improved when ion exchange resin was used as a material to increase surface area. Paclitaxel, with a reduced particle size due to the addition of a surface area increasing material during the fractional precipitation process, is believed to be particularly useful for practical applications of the drug.

기본 오프셋을 이용한 상선의 선체표면 격자계 생성방법 (Practical Method for Generating Surface Mesh using Offset Table)

  • 김우전;반석호
    • 대한조선학회논문집
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    • 제36권1호
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    • pp.61-69
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    • 1999
  • 수치 계산을 이용하여 선형의 유체동력학적인 특성을 신속히 파악하기 위해서는 선체표면 격자계를 생성하는 과정이 쉽고 자동화되어 있어야 한다. 이를 위하여 기본 스테이션 오프셋과 선수미 윤곽선만을 이용하여 선형을 정의하고, 이를 이용하여 퍼텐셜 유동이나 점성유동의 계산에 필요한 선체 표면 격자계를 손쉽게 생성할 수 있는 방법을 개발하였다. 선수와 선미 벌브를 가진 일반 상선의 선형을 표현하기 위해 수선의 양 끝단을 타일, 포물선, 쌍곡선, 3차 곡선 등의 조합으로 표시할 수 있게 하였다. 그리고 선수와 선미의 윤곽선을 격자계의 경계선으로 하였기 때문에 비선형 자유수면 조건을 이용한 조파저항 계산에서의 격자 변형이나 점성유동 해석을 위한 난류 경계층에서의 벽좌표의 정의가 종단면을 기준으로 한 종래의 격자에 비해 매우 편리하다고 할 수 있다.

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Geometric Correction for Uneven Quadric Projection Surfaces Using Recursive Subdivision of B$\acute{e}$zier Patches

  • Ahmed, Atif;Hafiz, Rehan;Khan, Muhammad Murtaza;Cho, Yongju;Cha, Jihun
    • ETRI Journal
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    • 제35권6호
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    • pp.1115-1125
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    • 2013
  • This paper presents a scheme for geometric correction of projected content for planar and quadratic projection surfaces. The scheme does not require the projection surface to be perfectly quadratic or planar and is therefore suitable for uneven low-cost commercial and home projection surfaces. An approach based on the recursive subdivision of second-order B$\acute{e}$zier patches is proposed for the estimation of projection distortion owing to surface imperfections. Unlike existing schemes, the proposed scheme is completely automatic, requires no prior knowledge of the projection surface, and uses a single uncalibrated camera without requiring any physical markers on the projection surface. Furthermore, the scheme is scalable for geometric calibration of multi-projector setups. The efficacy of the proposed scheme is demonstrated using simulations and via practical experiments on various surfaces. A relative distortion error metric is also introduced that provides a quantitative measure of the suppression of geometric distortions, which occurs as the result of an imperfect projection surface.