• 제목/요약/키워드: Boundary Nonlinear

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유한요소와 경계요소의 조합에 의한 반무한 영역 문제의 비선형해석 (A Nonlinear Analysis of Half Plane Problems Using Coupling of Finite Elements and Boundary Elements)

  • 김문겸;임윤묵
    • 전산구조공학
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    • 제2권1호
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    • pp.55-64
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    • 1989
  • 본 논문에서는 경계요소법과 비선형 유한요소법의 각 장점을 이용하여 반무한 영역을 가진 구조체의 해석방법을 논하였다. 여기서, 반무한 경계요소는 Melan의 반무한 평면에 대한 해로부터 구성하였다. 비선형 유한요소는 지하구조물에서 주로 접할 수 있는 탄소성 재료의 비균질성 또는 불규칙성을 모형화하기 위하여 사용하였다. 본 조합방법의 검증을 위하여 얕은 터널에 일정한 내압이 작용하는 경우를 택하여, 비선형 유한요소법과 조합방법의 결과를 비교하였다. 비교결과, 개발된 조합방법이 다른 해석방법에 비해 충분한 정확도를 가짐을 알 수 있었다.

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경계부 강성 치환 기법을 이용한 대공간 구조물의 부분 비선형 시뮬레이션에 관한 연구 (A Study on Nonlinear Partial Simulation of Spatial Structure Using Rigid Replacement Method of Boundary)

  • 김승덕;정혜원
    • 한국공간구조학회논문집
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    • 제19권2호
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    • pp.17-25
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    • 2019
  • In this study, we propose a new scheme of nonlinear analysis for Incheon International Airport Terminal-2 which was opened on January of 2018 for the Olympic Winter Games of PyeongChang in South Korea. The terminal was built by a single layered irregular space frame. It has hard problems for nonlinear analysis geometrically, because of a limitation of personal computer's ability by the number of rigid joints in the roof. Therefore we attempt easier approach to be chosen a center part of the roof instead of the whole structure, and to substitute the other boundary parts as springs. The scheme shows some merits for saving memory and calculation time and so on.

비선형 PSE를 이용한 압축성 경계층의 안정성 해석 (STABILITY ANALYSIS OF COMPRESSIBLE BOUNDARY LAYER IN CURVILINEAR COORDINATE SYSTEM USING NONLINEAR PSE)

  • ;박승오
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2007년도 추계 학술대회논문집
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    • pp.134-140
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    • 2007
  • Nonlinear parabolized stability equations for compressible flow in general curvilinear coordinate system are derived to deal with a broad range of transition prediction problems on complex geometry. A highly accurate finite difference PSE code has been developed using an implicit marching procedure. Blasius flow is tested. The results of the present computation show good agreement with DNS data. Nonlinear interaction can make the T-S fundamental wave more unstable and the onset of its amplitude decay is shifted downstream relative to linear case. For nonlinear calculations, rather small difference in initial amplitude can produce large change during nonlinear region. Compressible secondary instability at Mach number 1.6 is also simulated and showed that 1.1% initial amplitude for primary mode is enough to trigger the secondary growth.

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OSCILLATIONS OF CERTAIN NONLINEAR DELAY PARABOLIC BOUNDARY VALUE PROBLEMS

  • Zhang, Liqin;Fu, Xilin
    • Journal of applied mathematics & informatics
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    • 제8권1호
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    • pp.137-149
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    • 2001
  • In this paper we consider some nonlinear parabolic partial differential equations with distributed deviating arguments and establish sufficient conditions for the oscillation of some boundary value problems.

MULTIPLE SOLUTIONS FOR THE SYSTEM OF NONLINEAR BIHARMONIC EQUATIONS WITH JUMPING NONLINEARITY

  • Jung, Tacksun;Choi, Q-Heung
    • 충청수학회지
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    • 제20권4호
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    • pp.551-560
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    • 2007
  • We prove the existence of solutions for the system of the nonlinear biharmonic equations with Dirichlet boundary condition $$\{^{-{\Delta}^2u-c{\Delta}u+{\gamma}(bu^+-av^-)=s{\phi}_1\;in\;{\Omega},\;}_{-{\Delta}^2u-c{\Delta}u+{\delta}(bu^+-av^-)=s{\phi}_1\;in\;{\Omega}}$$, where $u^+$ = max{u, 0}, ${\Delta}^2$ denotes the biharmonic operator and ${\phi}_1$ is the positive eigenfunction of the eigenvalue problem $-{\Delta}$ with Dirichlet boundary condition.

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A NOTE ON THE EXISTENCE OF SOLUTIONS OF HIGHER-ORDER DISCRETE NONLINEAR STURM-LIOUVILLE TYPE BOUNDARY VALUE PROBLEMS

  • Liu, Yuji
    • Journal of applied mathematics & informatics
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    • 제27권1_2호
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    • pp.205-215
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    • 2009
  • Sufficient conditions for the existence of at least one solution of the boundary value problems for higher order nonlinear difference equations $\{{{{{\Delta^n}x(i-1)=f(i,x(i),{\Delta}x(i),{\cdots},\Delta^{n-2}x(i)),i{\in}[1,T+1],\atop%20{\Delta^m}x(0)=0,m{\in}[0,n-3],}\atop%20\Delta^{n-2}x(0)=\phi(\Delta^{n-1}(0)),}\atop%20\Delta^{n-1}x(T+1)=-\psi(\Delta^{n-2}x(T+1))}\$. are established.

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EXISTENCE OF NONTRIVIAL SOLUTIONS OF A NONLINEAR BIHARMONIC EQUATION

  • Jin, Yinghua;Choi, Q-Heung;Wang, Xuechun
    • Korean Journal of Mathematics
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    • 제17권4호
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    • pp.451-460
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    • 2009
  • We consider the existence of solutions of a nonlinear biharmonic equation with Dirichlet boundary condition, ${\Delta}^2u+c{\Delta}u=f(x, u)$ in ${\Omega}$, where ${\Omega}$ is a bounded open set in $R^N$ with smooth boundary ${\partial}{\Omega}$. We obtain two new results by linking theorem.

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