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相关论文: An inverse problem for an abstract evolution equat…

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Let $u_t-a(t)u_{xx}=f(x, t)$ in $0\leq x \leq \pi,\,\,t\geq 0.$ Assume that $u(0,t)=u_1(t)$, $u(\pi,t)=u_2(t)$, $u(x,0)=h(x)$, and the extra data $u_x(0,t)=g(t)$ are known. The inverse problem is: {\it How does one determine the unknown…

偏微分方程分析 · 数学 2016-12-01 A. G. Ramm

We consider an inverse problem of determining a coefficient $p(x)$ of an evolution equation $\sigma\ppp_tu = a(x)\ppp_x^2u - p(x)u$ for $0<x<\ell$ and $0<t<T$, where $\sigma \in \C \setminus \{0\}$, $\ell>0$ and $T>0$ are arbitrarily given.…

偏微分方程分析 · 数学 2024-10-01 Oleg Y , Imanuvilov , Masahiro Yamamoto

An evolution problem for abstract differential equations is studied. The typical problem is: $$\dot{u}=A(t)u+F(t,u), \quad t\geq 0; \,\, u(0)=u_0;\quad \dot{u}=\frac {du}{dt}\qquad (*)$$ Here $A(t)$ is a linear bounded operator in a Hilbert…

动力系统 · 数学 2010-10-01 A. G. Ramm

This paper investigates an inverse random source problem for stochastic evolution equations, including stochastic heat and wave equations, with the unknown source modeled as $g(x)f(t)\dot{W}(t)$. The research commences with the…

偏微分方程分析 · 数学 2025-09-22 Xu Wang , Guanlin Yang , Zhidong Zhang

In this paper, we investigate a nonlinear inverse problem aimed at recovering a coefficient $a(t, x)$, dependent on both time and a subset of spatial variables, in a diffusion equation \( u_t - \Delta_x u - u_{yy} +a(t, x) u = f(t,x,y) \),…

偏微分方程分析 · 数学 2025-08-07 R. R. Ashurov , O. T. Mukhiddinova

In this paper, we consider the backward problem for fractional in time evolution equations $\partial_t^\alpha u(t)= A u(t)$ with the Caputo derivative of order $0<\alpha \le 1$, where $A$ is a self-adjoint and bounded above operator on a…

偏微分方程分析 · 数学 2022-11-30 S. E. Chorfi , L. Maniar , M. Yamamoto

In this work the authors consider an inverse source problem in the following stochastic fractional diffusion equation $$\partial_t^\alpha u(x,t)+\mathcal{A} u(x,t)=f(x)h(t)+g(x) \dot{\mathbb{W}}(t).$$ The interested inverse problem is to…

偏微分方程分析 · 数学 2018-10-09 Pingping Niu , Tapio Helin , Zhidong Zhang

In this work, forward and inverse problems for a time-fractional pseudo-parabolic equation $D_t^{\rho} [u(t) + \mu Au(t)] + \sigma(t) Au(t) = r(t)g$ are investigated in a Hilbert space, where $A$ is an unbounded, positive, self-adjoint…

偏微分方程分析 · 数学 2026-05-14 Ravshan Ashurov , Elbek Husanov

We survey some of our recent results on inverse problems for evolution equations. The goal is to provide a unified approach to solve various types of evolution equations. The inverse problems we consider consist in determining unknown…

偏微分方程分析 · 数学 2019-12-09 Kaïs Ammari , Mourad Choulli , Faouzi Triki

We consider, in a Hilbert space $H$, the convolution integro-differential equation $u''(t)-h*Au(t)=f(t)$, $0\le t\le T$, $h*v(t)=\int_0^t h(t-s)v(s) ds$, where $A$ is a linear closed densely defined (possibly selfadjoint and/or positive…

泛函分析 · 数学 2007-05-23 Alfredo Lorenzi , Alexander Ramm

When considering fractional diffusion equation as model equation in analyzing anomalous diffusion processes, some important parameters in the model, for example, the orders of the fractional derivative or the source term, are often unknown,…

偏微分方程分析 · 数学 2019-04-15 Zhiyuan Li , Masahiro Yamamoto

In the Hilbert space $H$, the inverse problem of determining the right-hand side of the abstract subdiffusion equation with the fractional Caputo derivative is considered. For the forward problem, a non-local in time condition $u(0)=u(T)$…

偏微分方程分析 · 数学 2023-08-11 Ravshan Ashurov , Marjona Shakarova

Under consideration are mathematical models of heat and mass transfer. We study inverse problems of recovering lower-order coefficients in a second order parabolic equation. The coefficients are representable in the form of a finite…

偏微分方程分析 · 数学 2024-12-23 S. G. Pyatkov , O. A. Soldatov

The inverse problem of determining the right-hand side of the subdiffusion equation with the fractional Caputo derivative is considered. The right-hand side of the equation has the form $f(x)g(t)$ and the unknown is function $f(x)$. The…

偏微分方程分析 · 数学 2023-02-28 Ravshan Ashurov , Shakarova Marjona

In this paper, we consider two linear inverse problems for the time-fractional wave equation, assuming that its right-hand side takes the separable form $f(t)h(x)$, where $t \geq 0$ and $x \in \Omega \subset R^N $. The objective is to…

偏微分方程分析 · 数学 2025-03-25 Durdiev Durdimurod Kalandarovich

In this work, we study the inverse problem of determining a potential coefficient in an abstract wave equation that includes a lower-order term. The equation incorporates a time-fractional derivative in the Caputo sense, as well as a…

偏微分方程分析 · 数学 2025-07-10 D. K. Durdiev , H. H. Turdiev , A. A. Rahmonov

In this paper we shall study the inverse problem relative to dynamics of the w function which is a special arithmetic function and shall get some results.

数论 · 数学 2015-05-13 Chaohua Jia

In this paper, we investigate the direct and linear inverse problems of identifying time-dependent and time-independent source terms in a time-fractional diffusion-wave equation, using measured data at an interior point of the time…

偏微分方程分析 · 数学 2025-08-11 Rahmonov Askar Ahmadovich

We consider the inverse problem of determining the density coefficient appearing in the wave equation from separated point source and point receiver data. Under some assumptions on the coefficients, we prove uniqueness results.

偏微分方程分析 · 数学 2019-06-24 Manmohan Vashisth

Large time behavior of solutions to abstract differential equations is studied. The corresponding evolution problem is: $$\dot{u}=A(t)u+F(t,u)+b(t), \quad t\ge 0; \quad u(0)=u_0. \qquad (*)$$ Here $\dot{u}:=\frac {du}{dt}$, $u=u(t)\in H$,…

动力系统 · 数学 2010-12-14 A. G. Ramm
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