• 제목/요약/키워드: Stokes

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FINITE ELEMENT ANALYSIS FOR A MIXED LAGRANGIAN FORMULATION OF INCOMPRESSIBLE NAVIER-STOKES EQUATIONS

  • Kim, Hong-Chul
    • 대한수학회지
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    • 제34권1호
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    • pp.87-118
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    • 1997
  • This paper is concerned with a mixed Lagrangian formulation of the wiscous, stationary, incompressible Navier-Stokes equations $$ (1.1) -\nu\Delta u + (u \cdot \nabla)u + \nabla_p = f in \Omega $$ and $$ (1.2) \nubla \cdot u = 0 in \Omega $$ along with inhomogeneous Dirichlet boundary conditions on a portion of the boundary $$ (1.3) u = ^{0 on \Gamma_0 _{g on \Gamma_g, $$ where $\Omega$ is a bounded open domain in $R^d, d = 2 or 3$, or with a boundary $\Gamma = \partial\Omega$, which is composed of two disjoint parts $\Gamma_0$ and $\Gamma_g$.

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PULLBACK ATTRACTORS FOR 2D g-NAVIER-STOKES EQUATIONS WITH INFINITE DELAYS

  • Quyet, Dao Trong
    • 대한수학회논문집
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    • 제31권3호
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    • pp.519-532
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    • 2016
  • We consider the first initial boundary value problem for the 2D non-autonomous g-Navier-Stokes equations with infinite delays. We prove the existence of a pullback $\mathcal{D}$-attractor for the continuous process associated to the problem with respect to a large class of non-autonomous forcing terms.

비압축성 Navier-Stokes 방정식을 이용한 추력 편향 노즐 해석(원통에서 사각형으로 변환하는 내부 흐름을 중심으로) (A Flow Analysis of Vectored Thrust Nozzle Using Incompressible Navier-Stokes Solver)

  • 신대용;윤용현
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 1997년도 추계 학술대회논문집
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    • pp.66-72
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    • 1997
  • Circular-to-rectangular transition ducts are used as exhaust components of high performance fighter aircraft with vectored thrust nozzles. Three-dimensional incompressible Navier-Stokes solver is used to analyze the transition duct. Cross sections of transition duct are defined by superelliptic equation. The grid system is generated by Non-Uniform Rational B-Spline, after generating surface grid by blending the cross sections. Good agreement between the results of the computational simulation and the experimental data is observed.

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Legendre Tau Method for the 2-D Stokes Problem

  • Jun, SeRan;Kang, Sungkwon;Kwon, YongHoon
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제4권2호
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    • pp.111-133
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    • 2000
  • A Legendre spectral tau approximation scheme for solving the two-dimensional stationary incompressible Stokes equations is considered. Based on the vorticity-stream function formulation and variational forms, boundary value and normal derivative of vorticity are computed. A factorization technique for matrix stems based on the Schur decomposition is derived. Several numerical experiments are performed.

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A MIXED FINITE ELEMENT METHOD FOR NAVIER-STOKES EQUATIONS

  • Elakkad, Abdeslam;Elkhalfi, Ahmed;Guessous, Najib
    • Journal of applied mathematics & informatics
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    • 제28권5_6호
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    • pp.1331-1345
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    • 2010
  • This paper describes a numerical solution of Navier-Stokes equations. It includes algorithms for discretization by finite element methods and a posteriori error estimation of the computed solutions. In order to evaluate the performance of the method, the numerical results are compared with some previously published works or with others coming from commercial code like ADINA system.

다중 격자 Navier-Stokes 해석을 위한 예조건화된 다단계 시간 전진 기법 (Preconditioned Multistage time stepping for the Multigrid Navier-Stokes Solver)

  • 김윤식;권장혁;최윤호;이승수
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2002년도 춘계 학술대회논문집
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    • pp.59-64
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    • 2002
  • In this paper, the preconditioned multistage time stepping methods which are popular multigrid smoothers is implemented for the compressible Navier-Stokes calculation with full-coarsening multigrid method. The convergence characteristic of the point-Jacobi and Alternating direction line Jacobi(DDADI) preconditioners are studied. The performance of 2nd order upwind numerical fluxes such as 2nd order upwind TVD scheme and MUSCL-type linear reconstruction scheme are compared in the inviscid and viscous turbulent flow caculations.

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PS-LCI를 이용한 혈당 농도에 따른 Stokes 파라미터 측정 (Measurement of Stokes parameter changes due to blood glucose using PS-LCI)

  • 이상원;김법민
    • 한국광학회:학술대회논문집
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    • 한국광학회 2003년도 하계학술발표회
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    • pp.258-259
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    • 2003
  • 최근 수년간 polarimetry, Raman spectroscopy, near infrared (NIR) absorption spectroscopy, NIR scattering, optoacoustics 등의 방법을 통하여 비침습적으로 Glucose의 농도를 측정하려는 연구가 많이 시도되었다. 일반적으로 이들 방법은 sensitivity 와 signal-to-noise ratio가 매우 낮고 복잡한 알고리즘이 요구되어져 glucose 농도 측정에 한계가 있음이 드러났다. 본 연구에서는 polarization sensitive low coherence interferometer (PS-LCI) 기법을 이용하여 농도에 따른 stokes parameters를 측정함으로써 비침습적으로 glucose를 측정하는 것이 가능한지 알아보는데 그 목적이 있다. (중략)

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A UNIFIED STABILIZED FINITE VOLUME METHOD FOR STOKES AND DARCY EQUATIONS

  • Boukabache, Akram;Kechkar, Nasserdine
    • 대한수학회지
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    • 제56권4호
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    • pp.1083-1112
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    • 2019
  • In this paper, we present and analyze a cell-centered collocated finite volume scheme for incompressible flows to compute solutions simultaneous to Stokes and Darcy equations by applying a pressure jump stabilization term to avoid locking. We prove that the new stabilized FV formulation satisfies a discrete inf-sup condition and error estimates for both problems. Finally, we present some numerical examples confirming this analysis.

Isolation of flavonoids from Rhus verniciflua STOKES

  • Kim, Ho-Kyoung;Lee, A-Yeong;Kim, Jung-Hee;Jeon, Won-Kyung
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.258.2-258.2
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    • 2003
  • Rhus verniciflua STOKES (RVS) belongs to Anacardiaceae and grows Korea, China and Japan. distributed in the northeastern Asia. Rhus verniciflua STOKES has been used for anthelmintic medicine, stomachache, emmenagogue and constipation in oriental medicine. From the EtOAc fraction of 70% MeOH extracts, flavonoids were isolated by column chromatography using ODS, Sephadex LH-20 and silica gel. The structure of these compounds were identified on the $^1$H-NMR, $\^$13/C-NMR and FAB/MS spectroscopic methods.

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GLOBAL AXISYMMETRIC SOLUTIONS TO THE 3D NAVIER-STOKES-POISSON-NERNST-PLANCK SYSTEM IN THE EXTERIOR OF A CYLINDER

  • Zhao, Jihong
    • 대한수학회보
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    • 제58권3호
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    • pp.729-744
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    • 2021
  • In this paper we prove global existence and uniqueness of axisymmetric strong solutions for the three dimensional electro-hydrodynamic model based on the coupled Navier-Stokes-Poisson-Nernst-Planck system in the exterior of a cylinder. The key ingredient is that we use the axisymmetry of functions to derive the Lp interpolation inequalities, which allows us to establish all kinds of a priori estimates for the velocity field and charged particles via several cancellation laws.