A filter method for inverse nonlinear sideways heat equation

AbstractIn this paper, we study a sideways heat equation with a nonlinear source in a bounded domain, in which the Cauchy data at $x = \mathcal {X}$x=X are given and the solution in $0 \le x < \mathcal {X}$0≤x<X is sought. The problem is severely ill-posed in the sense of Hadamard. Based on the fundamental solution to the sideways heat equation, we propose to solve this problem by the filter method of degree α, which generates a well-posed integral equation. Moreover, we show that its solution converges to the exact solution uniformly and strongly in $\mathscr {L}^{p}(\omega,\mathcal {X};\mathscr {L}^{2}(\mathbb {R}))$Lp(ω,X;L2(R)), $\omega\in [0,\mathcal {X})$ω∈[0,X) under a priori assumptions on the exact solution. The proposed regularized method is illustrated by numerical results in the final section.