• 제목/요약/키워드: Material balance

검색결과 528건 처리시간 0.029초

흐름효과를 고려한 액정의 시뮬레이션 (Simulation of Liquid Crystals Considering Flow Effect)

  • 김훈;박우상
    • 한국전기전자재료학회논문지
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    • 제19권3호
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    • pp.260-266
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    • 2006
  • In this paper, We coupled fluid balance and director balance equation from Ericksen-Leslie's continuum theory and observed the motion of Liquid Crystal molecular. We simulated flow velocity and director distribution in which flow effect is considered in switching on and switching off state. We interpreted the dynamic response characteristic caused by the flow. As the result of the simulation, We could see the flow effect. In the case of Twisted Nematic(TN) cell, this flow caused abnormal twist temporarily in switching off state. We could prove that this abnormal twist is a direct cause of optical bounce phenomenon known well until now with the result of simulation. In addition, We analyzed the mechanism of the fast response due to flow in the case of Optically Compensated Bend(OCB) cell.

P의 함량에 따른 Sn-Ag-Cu 및 Sn-Cu 무연솔더의 특성평가 (Characterization of the Sn-Ag-Cu and Sn-Cu Lead-free Solder by adding P)

  • 신영의;황성진
    • 한국전기전자재료학회논문지
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    • 제16권6호
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    • pp.549-554
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    • 2003
  • The purpose of this paper is to investigate the solder properties by the change of P mass percentage. Tension test, wetting balance test, spread test, and analysis of intermetallic compound after isothermal aging of Sn-2.5Ag-0.7Cu-0.005P, Sn-2.5Ag-0.7Cu-0.01P, Sn-2.5Ag-0.7Cu-0.02P, Sn-0.7Cu-0.005P were performed. Adding P in the solder alloys resulted in improvement of tensile strength, reduction of intermetallic compound growth, reduction of oxidization in fusible solders under wave soldering. After comparing solder alloy containing P with tin-lead eutectic solder alloy, P contained solders alloys showed much better solder properties than eutectic solder alloy. Furthermore, this solder alloy presented remarkable properties than any other lead-free solder alloy.

흐름효과를 고려한 IPS-LCDs, VA-LCDs의 전기광학적 특성 시뮬레이션 (Simulation of Electro-optical Properties of IPS-LCDs and VA-LCOs Considering Flow Effect)

  • 김훈배;박우상
    • 한국전기전자재료학회논문지
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    • 제20권2호
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    • pp.167-172
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    • 2007
  • In this paper, we analyzed the molecular behavior of IPS-LCDs and VA-LCDs by using numerical simulation. The numerical simulation was performed on the basis of Ericksen-Leslie continuum theory. To improve the accuracy of the calculation, we considered fluid balance equation and director balance equation at the same time. thus, we calculated the flow effect for both switching on and off states. As the results of simulation, we confirmed abnormal twist in IPS-LCDs and fast molecular behavior in VA-LCDs which could influence response time.

산업연관분석법에 의한 궤도시스템의 환경부하 평가 (Study on assessment of the environmental impacts for track system by Input-Output Analysis)

  • 김용기;이철규;전용삼;조현정
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집
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    • pp.73-76
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    • 2009
  • LCA is nowadays getting popular as a tool to assess the environmental impacts. We can assess the environmental impacts of products and also compare the environmental performance between products with LCA. Furthermore, the LCA results can be used for designing eco-friendly products. But LCA needs an enormous amount of data collection, calculations of energy and material balance. which required to spend pretty much time and cost. However, If we use Input-Output Analysis, There is a lot of advantages that we can save time and cost to calculate and also analyze energy-material balance more comprehensively. Therefore, we implemented the fundamental research of the environmental impact assessment on railway system using life cycle inventory analysis and Input-Output Analysis method.

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Twisted Nematic(TN) 액정에서의 흐름효과 해석 (Analysis on the Flow Effect of the Twisted Nematic liquid Crystals)

  • 김훈;박우상
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.76-78
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    • 2005
  • We coupled fluid balance equation and director balance equation from Ericksen-Leslie's continuum theory and observed the motion of Twisted Nematic (TN) Liquid Crystals. We simulated flow velocity distribution and director distribution. We interpreted the dynamic response characteristic caused by the flow. As the result of the simulation, We could see the flow effect. And this flow caused abnormal twist to 4msec in switching off state. We could prove that this abnormal twist is a direct cause of optical bounce phenomenon known well until now with the result of simulation.

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Nonlinear damping and forced vibration analysis of laminated composite plates with composite viscoelastic core layer

  • Youzera, Hadj;Ali, Abbache;Meftah, Sid Ahmed;Tounsi, Abdelouahed;Hussain, Muzamal
    • Steel and Composite Structures
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    • 제44권1호
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    • pp.91-104
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    • 2022
  • The purpose of the present work is to study the parametric nonlinear vibration behavior of three layered symmetric laminated plate. In the analytical formulation; both normal and shear deformations are considered in the core layer by means of the refined higher-order zig-zag theory. Harmonic balance method in conjunction with Galerkin procedure is adopted for simply supported laminate plate, to obtain its natural and damping properties. For these aims, a set of complex amplitude equations governed by complex parameters are written accounting for the geometric nonlinearity and viscoelastic damping factor. The frequency response curves are presented and discussed by varying the material and geometric properties of the core layer.

부품ㆍ소재 산업의 발전을 위한 정보지원사업의 필요성 (The Necessity of Technology Information Service for Material & Component Industry in Korea)

  • 이창환;여운동
    • 기술혁신학회지
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    • 제6권1호
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    • pp.125-136
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    • 2003
  • This paper studies directions for technology information service on Korea material & component industry which is a main course for the deficit of balance of payments in Korea. We have got survey results through e-mail or fax, for the degree of the necessity of the service and the contents for the service. Finally, we will recommend the check point for the service, and for the policy.

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일본 기수호(Lake Obuchi)에서 생태계 모델의 개발과 적용 (Development and Application of the Ecosystem Model in Brackish Lake Obuchi, Japan)

  • Kondo, Kunio;Inaba, Jiro;Hosoda, Masahiro;Kutsukake, Hiroshi;Seike, Yasushi;Nakata, Kisaburo;Shinji, Ueda
    • 생태와환경
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    • 제37권4호통권109호
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    • pp.448-454
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    • 2004
  • 반폐쇄성 기수호인 Obuchi호에서 수질과 생물학적 mass balance를 평가하기 위해 생태계 모델을 개발하고 적용하였다. 2001년 1월부터 2002년 12월까지 관찰된 조석의 차이, 강으로부터의 유입수 및 기상 변수들에 대한 시계열 자료들을 hydrodynamic 모델의 변수들로 접목시켰다. 수질과 생물생체량 balance는 생태계 모델에 의해 평가되었으며, 모의된 수질 값은 관찰 값과 일치하였다. 호수에서 모델에 의해 계산된 POC와 식물플랑크톤, 동물플랑크톤의 carbon 함량은 각각 7,200 kg, 1,500 kg, 22 kg으로 나타났으며, 이는 관찰 값 POC (5,900 kg), 식물플랑크톤 (3,800 kg)밍, 동물플랑크톤 (150 kg)과 어느 정도 비교할 수 있었다.

염색가공분야에서 청정생산활동 접금방법 (Cleaner Production System in Dyeing & Finishing Its Approaching Mehods)

  • 이혜정;남창우;박영환
    • 청정기술
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    • 제9권2호
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    • pp.87-100
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    • 2003
  • 본 연구는 청정생산기술의 개념을 염색가공분야에 도입시키기 위한 방법론을 제시한 것이다. 먼저 각 분야별 전문가로 이루어진 진단지도팀을 구성하여 대상업체에서 진행중인 제조공정 진행상태를 파악하고 사용하는 원부자재의 성능 및 환경적 분석과 폐수의 환경적 분석을 실시하였다. 원부자재(조제 및 염료)의 환경성은 TOC, CODMn, CODCr, $BOD_5$의 항목으로 평가하였고, 발생되는 폐수는 TOC, CODMn, CODCr, $BOD_5$, TDS, pH의 항목으로 평가하였다. 또 물질수지 분석과 LCA 평가 후 다음 단계로 공정, 에너지, 원부자재, 생산관리, 일반관리에서의 문제점을 도출한 후 그 중에서 개선 대상을 선정하고 마지막 단계에서 각 부분에 대해 지도하여 개선토록 한 후 최종 개선 효과를 분석하였다.

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