• 제목/요약/키워드: Laplacian Operator

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유체-구조 연성 기법을 사용한 움직이는 2차원 실린더 주위의 유동 해석 (Fluid-structure interaction analysis of two-dimensional flow around a moving cylinder)

  • 이희범;이신형
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2011년 춘계학술대회논문집
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    • pp.68-74
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    • 2011
  • Recently, thanks to the advanced computational power and numerical methods, it is made possible to analyze the flow around moving bodies using computational fluid dynamics techniques. In those simulations, moving mesh techniques should be able to represent both the body motion and boundary deformation, which are frequently encountered in fluid-structure interaction and/or six degree-of-freedom problems. In the present study, the staggered loosely coupling algorithm was used for fluid-structure interaction and the Laplacian operator based technique was used for moving mesh. For the verification of the developed computational method, the flow around a two-dimensional cylinder was simulated and analyzed.

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TRANSLATION SURFACES OF TYPE 2 IN THE THREE DIMENSIONAL SIMPLY ISOTROPIC SPACE 𝕀13

  • Bukcu, Bahaddin;Karacan, Murat Kemal;Yoon, Dae Won
    • 대한수학회보
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    • 제54권3호
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    • pp.953-965
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    • 2017
  • In this paper, we classify translation surfaces of Type 2 in the three dimensional simply isotropic space ${\mathbb{I}}_3^1$ satisfying some algebraic equations in terms of the coordinate functions and the Laplacian operators with respect to the first, the second and the third fundamental form of the surface. We also give explicit forms of these surfaces.

WEAK SOLUTIONS AND ENERGY ESTIMATES FOR A DEGENERATE NONLOCAL PROBLEM INVOLVING SUB-LINEAR NONLINEARITIES

  • Chu, Jifeng;Heidarkhani, Shapour;Kou, Kit Ian;Salari, Amjad
    • 대한수학회지
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    • 제54권5호
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    • pp.1573-1594
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    • 2017
  • This paper deals with the existence and energy estimates of solutions for a class of degenerate nonlocal problems involving sub-linear nonlinearities, while the nonlinear part of the problem admits some hypotheses on the behavior at origin or perturbation property. In particular, for a precise localization of the parameter, the existence of a non-zero solution is established requiring the sublinearity of nonlinear part at origin and infinity. We also consider the existence of solutions for our problem under algebraic conditions with the classical Ambrosetti-Rabinowitz. In what follows, by combining two algebraic conditions on the nonlinear term which guarantees the existence of two solutions as well as applying the mountain pass theorem given by Pucci and Serrin, we establish the existence of the third solution for our problem. Moreover, concrete examples of applications are provided.

원전 증기 발생기 세관 검사용 비젼 시스템 개발에 관한 연구 (A Study on Development of a Vision System for the Test of Steam Generator in Nuclear Power Plants)

  • 왕한홍
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1996년도 춘계학술대회 논문집
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    • pp.200-204
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    • 1996
  • It is a great number of problem for the man to perform maintenance and repairing work owing to radioactive effusion for a nuclear fuel and the pollution of an related equipment in nuclear power plants. Therefore, the vision processing system presented in this research requires to maintain the good performance under the radioactive circumstances and to safety the real time processing system presented in this research requires to maintain the good performance under the radioactive circumstances and to safety the real time processing. The proposed vision scheme adapts the gradient and Laplacian operator to perform the high speed processing in an edge detection and the centroid formula at each direction to obtain the center position of a holes using DSPs

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LONG-TIME BEHAVIOR OF SOLUTIONS TO A NONLOCAL QUASILINEAR PARABOLIC EQUATION

  • Thuy, Le Thi;Tinh, Le Tran
    • 대한수학회논문집
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    • 제34권4호
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    • pp.1365-1388
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    • 2019
  • In this paper we consider a class of nonlinear nonlocal parabolic equations involving p-Laplacian operator where the nonlocal quantity is present in the diffusion coefficient which depends on $L^p$-norm of the gradient and the nonlinear term is of polynomial type. We first prove the existence and uniqueness of weak solutions by combining the compactness method and the monotonicity method. Then we study the existence of global attractors in various spaces for the continuous semigroup generated by the problem. Finally, we investigate the existence and exponential stability of weak stationary solutions to the problem.

EXISTENCE OF GLOBAL SOLUTIONS TO SOME NONLINEAR EQUATIONS ON LOCALLY FINITE GRAPHS

  • Chang, Yanxun;Zhang, Xiaoxiao
    • 대한수학회지
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    • 제58권3호
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    • pp.703-722
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    • 2021
  • Let G = (V, E) be a connected locally finite and weighted graph, ∆p be the p-th graph Laplacian. Consider the p-th nonlinear equation -∆pu + h|u|p-2u = f(x, u) on G, where p > 2, h, f satisfy certain assumptions. Grigor'yan-Lin-Yang [24] proved the existence of the solution to the above nonlinear equation in a bounded domain Ω ⊂ V. In this paper, we show that there exists a strictly positive solution on the infinite set V to the above nonlinear equation by modifying some conditions in [24]. To the m-order differential operator 𝓛m,p, we also prove the existence of the nontrivial solution to the analogous nonlinear equation.

CHARACTERIZING FUNCTIONS FIXED BY A WEIGHTED BEREZIN TRANSFORM IN THE BIDISC

  • Lee, Jaesung
    • Korean Journal of Mathematics
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    • 제27권2호
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    • pp.437-444
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    • 2019
  • For c > -1, let ${\nu}_c$ denote a weighted radial measure on ${\mathbb{C}}$ normalized so that ${\nu}_c(D)=1$. For $c_1,c_2>-1$ and $f{\in}L^1(D^2,\;{\nu}_{c_1}{\times}{\nu}_{c_2})$, we define the weighted Berezin transform $B_{c_1,c_2}f$ on $D^2$ by $$(B_{c_1,c_2})f(z,w)={\displaystyle{\smashmargin2{\int\nolimits_D}{\int\nolimits_D}}}f({\varphi}_z(x),\;{\varphi}_w(y))\;d{\nu}_{c_1}(x)d{\upsilon}_{c_2}(y)$$. This paper is about the space $M^p_{c_1,c_2}$ of function $f{\in}L^p(D^2,\;{\nu}_{c_1}{\times}{\nu}_{c_2})$ ) satisfying $B_{c_1,c_2}f=f$ for $1{\leq}p<{\infty}$. We find the identity operator on $M^p_{c_1,c_2}$ by using invariant Laplacians and we characterize some special type of functions in $M^p_{c_1,c_2}$.

On the use of spectral algorithms for the prediction of short-lived volatile fission product release: Methodology for bounding numerical error

  • Zullo, G.;Pizzocri, D.;Luzzi, L.
    • Nuclear Engineering and Technology
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    • 제54권4호
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    • pp.1195-1205
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    • 2022
  • Recent developments on spectral diffusion algorithms, i.e., algorithms which exploit the projection of the solution on the eigenfunctions of the Laplacian operator, demonstrated their effective applicability in fast transient conditions. Nevertheless, the numerical error introduced by these algorithms, together with the uncertainties associated with model parameters, may impact the reliability of the predictions on short-lived volatile fission product release from nuclear fuel. In this work, we provide an upper bound on the numerical error introduced by the presented spectral diffusion algorithm, in both constant and time-varying conditions, depending on the number of modes and on the time discretization. The definition of this upper bound allows introducing a methodology to a priori bound the numerical error on short-lived volatile fission product retention.

AN EXISTENCE OF THREE DIFFERENT NON-TRIVIAL SOLUTIONS FOR DISCRETE ANISOTROPIC EQUATIONS WITH TWO REAL PARAMETERS

  • Ahmed A.H., Alkhalidi;Haiffa Muhsan B., Alrikabi;Mujtaba Zuhair, Ali
    • Nonlinear Functional Analysis and Applications
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    • 제27권4호
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    • pp.855-867
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    • 2022
  • This study finds three different solutions (3-Sol's) for the fourth order nonlinear discrete anisotropic equations (DAE) with real parameter. We use the variational method(VM) and 𝜙p-Laplacian operator (𝜙p-LO) to prove the main results. In the following paper, we take the parameters λ, 𝜇 such that λ > 0 and 𝜇 ≥ 0 into consideration.

A Nonlinear Elliptic Equation of Emden Fowler Type with Convection Term

  • Mohamed El Hathout;Hikmat El Baghouri;Arij Bouzelmate
    • Kyungpook Mathematical Journal
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    • 제64권1호
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    • pp.113-131
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    • 2024
  • In this paper we give conditions for the existence of, and describe the asymtotic behavior of, radial positive solutions of the nonlinear elliptic equation of Emden-Fowler type with convection term ∆p u + 𝛼|u|q-1u + 𝛽x.∇(|u|q-1u) = 0 for x ∈ ℝN, where p > 2, q > 1, N ≥ 1, 𝛼 > 0, 𝛽 > 0 and ∆p is the p-Laplacian operator. In particular, we determine ${\lim}_{r{\rightarrow}}{\infty}\,r^{\frac{p}{q+1-p}}\,u(r)$ when $\frac{{\alpha}}{{\beta}}$ > N > p and $q\,{\geq}\,{\frac{N(p-1)+p}{N-p}}$.