• Title/Summary/Keyword: 열 탄성

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Ultimate Strength Evaluation of Through Plate Girder Bridge Using Nonlinear Inelastic Analysis (비선형비탄성해석을 활용한 하로 판형교의 극한강도 평가)

  • Jeon, Shin-Youl;Tai-Huu, Thai;Kim, Seung-Eock
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.1713-1718
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    • 2010
  • An ultimate strength evaluation of the through plate girder bridge using nonlinear inelastic analysis is presented. In this method, separate member capacity checks after analysis are not required, because the stability and strength of the structural system and its component members can be rigorously treated in analysis. The method captures the inelastic redistribution of internal forces throughout a structural system, and allows an economic use of material for highly indeterminate steel bridges.

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Characterization of Flaws in the Elastic Medium by Time Domain Born Approximation (시간 정의구역 Born 근사에 의한 탄성매질에서의 결함에 관한 연구)

  • Yi, J.Y.;Lee, S.K.;Lee, J.O.;Kim, Y.H.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.3 no.1
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    • pp.5-11
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    • 1983
  • The impulse response function are studied using time domain Born approximation in two cases; firstly when the material parameters of a flaw are constant, secondly when the parameters are varying with positions. From the impulse response functions, characteristics can be learned about a flaw with high symmetry.

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고속전철용 디스크 브레이크의 열탄성 마멸에 관한 수치적 연구

  • 황준태;김청균
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1999.11a
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    • pp.269-275
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    • 1999
  • This paper presents the results of thermoelastic wear phenomena in ventilated disk brakes for a high-speed train using finite element method. The computed results show that the sinusoidal distortions due to non-uniform distributions of temperature profiles may lead to thermoelastic wears at the rubbing surface. This may decrease the life of a disk brake and produce micro-cracks, noise and squeals between two rubbing surfaces.

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Finite Element Analysis on the Thermoelastic Wear Behaviors for a High-Speed Disk Brake (고속용 디스크 브레이크의 열탄성 마멸거동에 관한 유한요소해석)

  • 이일권;김청균
    • Tribology and Lubricants
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    • v.15 no.4
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    • pp.291-296
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    • 1999
  • This paper presents the results of thermoelastic wear behaviors in ventilated disk brakes for a high-speed automotive and train using the finite element method. The computed results show that the sinusoidal distortions due to non-uniform distributions of temperature profiles may lead to thermoelastic wears on the rubbing surface. This may decrease the service life of a disk brake and produce micro-cracks, noise and squeals between two rubbing surfaces.

Dynamics of an Axially Moving Thermoelastic Beam-Plate (축방향으로 이동하는 열탄성 보-평판의 동특성 해석)

  • 김도연;이우식
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2003.10a
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    • pp.21-28
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    • 2003
  • The use of frequency-dependent spectral element matrix (or dynamic stiffness matrix) in structural dynamics may Provide very accurate solutions, while it reduces the number of degrees of freedom to improve the computational efficiency and cost problems. Thus, this paper develops a spectral element model for the coupled thermoelastic beam-plate moving with constant speed under uniform in-plane tension.

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Stress analysis and fatigue failure of rubber in automobile (자동차용 고무재의 응력해석 및 피로파손)

  • 이강용;백운천
    • Journal of the korean Society of Automotive Engineers
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    • v.12 no.2
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    • pp.11-15
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    • 1990
  • 고무재료는 강재에 비해 큰 탄성변형을 할 수 있고 충격 흡수능력이 뛰어나므로 자동차에서도 진동문제 및 승차감을 향상시키기 위하여 엔진 마운트, suspension bushing등을 비롯한 여러 곳에 사용되고 있다. 여기에 이용되는 고무재의 요구조건은 1) 피로수명이 충분히 길것, 2) 열 및 산화에 강할 것, 3) 소음이 없을 것 등이다. 본 고에서는 1)번의 요구조건을 기준으로 고무재의 기본적인 역학적 특성 및 해석방법을 소개하고자 한다.

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Analysis of Frictional Power Loss Due to the Effects of Elastic Deformation in the Piston Skirt Profile (탄성변형을 고려한 피스톤 스커트의 마찰 손실 해석)

  • 조준행;장시열
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2000.11a
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    • pp.385-396
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    • 2000
  • The secondary motion of piston occurs due to the transient forces and moments in the clearances between piston skirt and cylinder liner The motions are very related to the skirt profile and the magnitude of piston-pin offset. Above all, the elastic deformation is another major effect on the piston secondary motion that has not been considered in the previous researches. In this work, the effects of elastic deformation of the piston skirt on the secondary piston motion are studied for the frictional power loss by using commercial softares, PISDYN and ANSYS.

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Thermo-elastic Effect Analysis of Optical Performance for Thermal Imaging Camera (열상카메라 광학성능의 열탄성 효과 분석)

  • 김현규;김창우;서상호;유병철;김창오
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.07a
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    • pp.144-145
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    • 2003
  • 열상카메라는 빛이 전혀 없는 야간에도 선명한 영상을 획득할 수 있도록 구성된 장비이다. 이러한 열상카메라는 야간 영상 획득에 있어서 많은 분야에서 사용되고 또한 반드시 사용되어야만 한다. 또한 열상카메라를 구성하기 위하여 사용되는 렌즈의 재질은 온도에 대한 굴절률의 변화가 크고 경도가 낮아 외부 환경에 대한 영향성이 크다. 열상카메라의 성능에 영향을 주는 외부 환경 요소로는 열상카메라가 사용되는 환경에서 발생하는 진동의 요인과 내부 및 외부로부터 받는 온도에 대한 요인이다. (중략)

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A Study on Variations of mechanical properties of Carbon-epoxy Composites with Thermal Fatigue Cycles or Thermal Shock Cycles (열적 피로 및 충격이 부가된 Carbon-Epoxy 복합재료의 기계적 특성에 관한 연구)

  • Lee, Dong-Sik;Park, Se-Man
    • Korean Journal of Materials Research
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    • v.10 no.5
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    • pp.354-659
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    • 2000
  • Applications of composite materials have been in progress noticeably in manufacturing areas of automotive, aircraft and in other industries, resulting in ensuing research activities. Carbon-epoxy, one of major composite materials, is investigated for its thermal characteristics. Upon treatments of the composite material with repeated heatings and coolings variations of its elastic constants are monitored to reveal the thermal nature of the composite material. In this study, generally, changes in elastic constants are observed to occur mostly during the first 10~20 thermal cycles. Values of G(sub)13 remain almost unchanged except a minor decrease. However in the observed small changes thermal shocks produce less effect than thermal fatigues. On the other hand, values of $E_1$show gradual increases with the num-ber of applied thermal cycles and temperatures. Meanwhile, values of $E_2$ and G(sub)23 decrease to a certain extent in the early stage during the applications of thermal cycling but are not appreciable affected by frequencies of thermal cy-cles. Also, thermal shocks are observed to induce different effects depending on treatment temperatures.

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