• Title/Summary/Keyword: s equation

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NUMERICAL ANALYSIS OF ERGUN'S EQUATION FOR INTERIOR BALLISTIC ANALYSIS (강내탄도 해석에 사용되는 Ergun식에 관한 수치적 연구)

  • Bae, S.W.;Sung, H.G.;Roh, T.S.
    • 한국전산유체공학회:학술대회논문집
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    • 2010.05a
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    • pp.473-478
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    • 2010
  • In this study, the Ergun's equation has been verified in order to calculate pressure drop of the two phase flow. The equation had been used in the high Reynolds number region for interior ballistic analysis in spite of being verified in the low Reynolds number region. Therefore additional verification seems to be inevitable. Thus, the validity of the equation has been verified using CFD in the high Reynolds number cases of the diameter-particle ratio 10, 13 and 16.

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MOTION OF VORTEX FILAMENTS IN 3-MANIFOLDS

  • PAK, HEE-CHUL
    • Bulletin of the Korean Mathematical Society
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    • v.42 no.1
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    • pp.75-85
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    • 2005
  • In this paper, the visco-Da-Rios equation; (0.1) ($$\frac{{\partial}{\gamma}}{{\partial}t}=\frac{{\partial}{\gamma}}{{\partial}s}{\bigwedge}\frac{D}{ds}\frac{{\partial}{\gamma}}{{\partial}s}+{\nu}\frac{{\partial}{\gamma}}{{\partial}s}$$) is investigated on 3-dimensional complete orientable Riemannian manifolds. The global existence of solution is discussed by trans-forming (0.1) into a cubic nonlinear Schrodinger equation for complete orient able Riemannian 3-manifolds of constant curvature.

WAVEFRONT SOLUTIONS IN THE DIFFUSIVE NICHOLSON'S BLOWFLIES EQUATION WITH NONLOCAL DELAY

  • Zhang, Cun-Hua
    • Journal of applied mathematics & informatics
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    • v.28 no.1_2
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    • pp.49-58
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    • 2010
  • In the present article we consider the diffusive Nicholson's blowflies equation with nonlocal delay incorporated into an integral convolution over all the past time and the whole infinite spatial domain $\mathbb{R}$. When the kernel function takes a special function, we construct a pair of lower and upper solutions of the corresponding travelling wave equation and obtain the existence of travelling fronts according to the existence result of travelling wave front solutions for reaction diffusion systems with nonlocal delays developed by Wang, Li and Ruan (J. Differential Equations, 222(2006), 185-232).

MULTIGRID METHOD FOR NONLINEAR INTEGRAL EQUATIONS

  • HOSAE LEE
    • Journal of applied mathematics & informatics
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    • v.4 no.2
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    • pp.487-500
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    • 1997
  • In this paper we introduce a multigrid method for solving the nonliear Urysohn integral equation. The algorithm is derived from a discrete resolvent equation which approximates the continuous resolvent equation of the nonlinear Urysohn integral equa-tion. The algorithm is mathematically equivalent to Atkinson's adap-tive twogrid iteration. But the two are different computationally. We show the convergence of the algorithm and its equivalence to Atkinson's adaptive twogrid iteration. in our numerical example we compare our algorithm to other multigrid methods for solving the nonliear Urysohn integral equation including the nonlinear multigrid nethod introduced by hackbush.

Obstacle avoidance method in the UAV

  • Bae, Young-Chul;Kim, Chun-Suk;Kim, Yig-On
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2004.10a
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    • pp.7-10
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    • 2004
  • In this paper, we propose a method to avoid obstacles that have unstable limit cycles in a chaos trajectory surface. We assume all obstacles in the chaos trajectory surface have a Van der Pol equation with an unstable limit cycle. When a chaos UAVs meet an obstacle in an Arnold equation or Chua's equation trajectory, the obstacle reflects the UAV

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Target searching method in the UAV

  • Bae, Young-Chul;Kim, Chun-Suk;Kim, Yi-Gon
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2004.10a
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    • pp.11-14
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    • 2004
  • In this paper, we propose a method to target searching method that have unstable limit cycles in a chaos trajectory surface. We assume all targets in the chaos trajectory surface have a Van der Pol equation with an unstable limit cycle When a chaos UAV meet the target in the Arnold equation, Chua's equation trajectory, the target absorptive the UAV

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A CONSERVATIVE NONLINEAR DIFFERENCE SCHEME FOR THE VISCOUS CAHN-HILLIARD EQUATION

  • Choo, S.M.;Chung, S.K.
    • Journal of applied mathematics & informatics
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    • v.16 no.1_2
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    • pp.53-68
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    • 2004
  • Numerical solutions for the viscous Cahn-Hilliard equation are considered using the Crank-Nicolson type finite difference method which conserves the mass. The corresponding stability and error analysis of the scheme are shown. The decay speeds of the solution in $H^1-norm$ are shown. We also compare the evolution of the viscous Cahn-Hilliard equation with that of the Cahn-Hilliard equation numerically and computationally, which has been given as an open question in Novick-Cohen[13].

ASYMTOTIC BEHAVIOUR OF THE VISCOUS CAHN-HILLIARD EQUATION

  • Choo, S.M.;Chung, S.K.
    • Journal of applied mathematics & informatics
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    • v.11 no.1_2
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    • pp.143-154
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    • 2003
  • Analytical solutions for the viscous Cahn-Hilliard equation are considered. Existence and uniqueness of the solution are shown. The exponential decay of the solution in H$^2$-norm, which is an improvement of the result in Elliott and Zheng[5]. We also compare the early stages of evolution of the viscous Cahn-Hilliard equation with that of the Cahn-Hilliard equation, which has been given as an open question in Novick-Cohen[8].

A Chaotic Underwater Robot (카오스 수중 로봇)

  • Kim, Chun-Suk;Bae, Young-Chul
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.937-941
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    • 2005
  • In this paper, we propose a chaotic underwater robots that have unstable limit cycles in a chaos trajectory surface with Arnold equation, Chua's equation. We assume all obstacles in the chaos trajectory surface have a Van der Pol equation with an unstable limit cycle. We also show computer simulation results of Arnold equation and Chua's equation chaos trajectories with one or more Van der Pol obstacles

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