• 제목/요약/키워드: nonlocal heat equation

검색결과 7건 처리시간 0.023초

BLOW UP OF SOLUTIONS WITH POSITIVE INITIAL ENERGY FOR THE NONLOCAL SEMILINEAR HEAT EQUATION

  • Fang, Zhong Bo;Sun, Lu
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제16권4호
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    • pp.235-242
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    • 2012
  • In this paper, we investigate a nonlocal semilinear heat equation with homogeneous Dirichlet boundary condition in a bounded domain, and prove that there exist solutions with positive initial energy that blow up in finite time.

Determination of Unknown Time-Dependent Heat Source in Inverse Problems under Nonlocal Boundary Conditions by Finite Integration Method

  • Areena Hazanee;Nifatamah Makaje
    • Kyungpook Mathematical Journal
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    • 제64권2호
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    • pp.353-369
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    • 2024
  • In this study, we investigate the unknown time-dependent heat source function in inverse problems. We consider three general nonlocal conditions; two classical boundary conditions and one nonlocal over-determination, condition, these genereate six different cases. The finite integration method (FIM), based on numerical integration, has been adapted to solve PDEs, and we use it to discretize the spatial domain; we use backward differences for the time variable. Since the inverse problem is ill-posed with instability, we apply regularization to reduce the instability. We use the first-order Tikhonov's regularization together with the minimization process to solve the inverse source problem. Test examples in all six cases are presented in order to illustrate the accuracy and stability of the numerical solutions.

A GN-based modified model for size-dependent coupled thermoelasticity analysis in nano scale, considering nonlocality in heat conduction and elasticity: An analytical solution for a nano beam with energy dissipation

  • Hosseini, Seyed Mahmoud
    • Structural Engineering and Mechanics
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    • 제73권3호
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    • pp.287-302
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    • 2020
  • This investigation deals with a size-dependent coupled thermoelasticity analysis based on Green-Naghdi (GN) theory in nano scale using a new modified nonlocal model of heat conduction, which is based on the GN theory and nonlocal Eringen theory of elasticity. In the analysis based on the proposed model, the nonlocality is taken into account in both heat conduction and elasticity. The governing equations including the equations of motion and the energy balance equation are derived using the proposed model in a nano beam resonator. An analytical solution is proposed for the problem using the Laplace transform technique and Talbot technique for inversion to time domain. It is assumed that the nano beam is subjected to sinusoidal thermal shock loading, which is applied on the one of beam ends. The transient behaviors of fields' quantities such as lateral deflection and temperature are studied in detail. Also, the effects of small scale parameter on the dynamic behaviors of lateral deflection and temperature are obtained and assessed for the problem. The proposed GN-based model, analytical solution and data are verified and also compared with reported data obtained from GN coupled thermoelasticity analysis without considering the nonlocality in heat conduction in a nano beam.

비국소 경계 조건들을 가진 상미분 방정식들의 근의 존재성에 음함수 정리들의 응용 I (Application of Implicit Function Theorem to Existence of Solutions to Ordinary Differential Equations with Nonlocal Boundary Conditions, I)

  • 도태석
    • 한국산업융합학회 논문집
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    • 제5권3호
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    • pp.219-224
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    • 2002
  • We consider the problem y"=a(x,y)(y-b), y(0)=0, y'(1)=g(y(${\xi}$), y'(${\xi}$)), (0${\xi}$ fixed in(0,1)) as a model of steady-slate heat conduction in a rod when the heat flux at the end x = 1 is determined by observation of the temperature and heat flux at some interior point ${\xi}$. We establish conditions sufficient for existence, uniqueness.

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비국소 경계 조건들을 가진 상미분 방정식들의 근의 존재성에 음함수 정리들의 응용 II (Application of Implicit Function Theorem to Existence of Solutions to Ordinary Differential Equations with Nonlocal Boundary Conditions, II)

  • 도태석
    • 한국산업융합학회 논문집
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    • 제5권4호
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    • pp.303-307
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    • 2002
  • We consider the problem y"=a(x,y)(y-b), (0$$y(0)=0,\;y^{\prime}(1)=g(y({\xi}),\;y^{\prime}({\xi})),\;{\xi}$$ fixed in (0,1). This is a model of steady-state heat conduction in a rod when the heat flux at the end x=1 is determined by observation of the temperature and heat flux at some interior point ${\xi}$. We establish conditions sufficient for existence, uniqueness, and positivity of solutions.

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비국소 경계 조건들을 가진 상미분 방정식들의 반무한 구간 상에서 근들의 존재성 (Existence of Solutions on a Semi-Infinite Interval for Ordinary Differential Equation with Nonlocal Boundary Conditions)

  • 도태석
    • 한국산업융합학회 논문집
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    • 제5권4호
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    • pp.309-312
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    • 2002
  • Motivated by the problem of steady-state heat conduction in a rod whose heat flux at one end is determined by observation of the temperature and heat flux at some point ${\xi}$ in the interior of the rod, we consider the problem y"(x)=a(x, y(x))y(x) (0$${\lim_{x{\rightarrow}{\infty}}}y(x)=0,\;y^{\prime}(0)=g(y({\xi}),\;y^{\prime}({\xi}))$$ for some fixed ${\xi}{\in}(0,{\infty})$. We establish conditions guaranteeing existence and uniqueness for this problem on the semi-infinite interval [0,${\infty}$).

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