in this paper we consider a petrovsky viscoelastic inverse source problem with memory term in the boundary condition. we obtain sufficient conditions on relaxation function and initial data for which the solutions of problem are asymptotically stable when the integral overdetermination tends to zero as time goes to infinity.

mathematical simulation of flow toward drains is an important and indispensable stage in drainage design and management. many related models have been developed, but most of them simulate the saturated flow toward drains without a due consideration of the unsaturated zone. in this study, the two dimensional differential equation governing saturated and unsaturated flow in porous media is numeri...

in this paper, two inverse problems of stephen kind with local (dirichlet) boundary conditions are investigated. in the first problem only a part of boundary is unknown and in the second problem, the whole of boundary is unknown. for the both of problems, at first, analytic expressions for unknown boundary are presented, then by using these analytic expressions for unknown boundaries and bounda...

Spectral factorization is a computational procedure for constructing minimumphase (stable inverse) filters required for recursive inverse filtering. We present a novel method of spectral factorization. The method iteratively constructs an approximation of the minimum-phase filter with the given autocorrelation by repeated forward and inverse filtering and rearranging the terms. This procedure i...

An adjoint based functional optimization technique in conjunction with the spectral stochastic finite element method is proposed for the solution of an inverse heat conduction problem in the presence of uncertainties in material data, process conditions and measurement noise. The ill-posed stochastic inverse problem is restated as a conditionally well-posed L2 optimization problem. The gradient...

We study inverse spectral analysis for finite and semi-infinite Jacobi matrices H. Our results include a new proof of the central result of the inverse theory (that the spectral measure determines H). We prove an extension of Hochstadt’s theorem (who proved the result in the case n = N) that n eigenvalues of an N ×N Jacobi matrix, H, can replace the first n matrix elements in determining H uniq...

We present a spectral and inverse spectral theory for the zero dispersion spectral problem associated with the Camassa-Holm equation. This is an alternative approach to that in [10] by Eckhardt and Teschl. Mathematics Subject Classification (2010). Primary 37K15, 34B40 ; Secondary 35Q35, 34L05.

For finite dimensional CMV matrices the classical inverse spectral problems are considered. We solve the inverse problem of reconstructing a CMV matrix by its Weyl’s function, the problem of reconstructing the matrix by two spectra of CMV operators with different “boundary conditions”, and the problem of reconstructing a CMV matrix by its spectrum and the spectrum of the CMV matrix obtained fro...

We present an approach to de Branges’s theory of Hilbert spaces of entire functions that emphasizes the connections to the spectral theory of differential operators. The theory is used to discuss the spectral representation of one-dimensional Schrödinger operators and to solve the inverse spectral problem.