A dynamic inverse problem for a one-dimensional system of the Hopf-type equations is considered. A theorem on local solvability in the class of functions
analytic in the variable *x* is proved.

The Cauchy problem for a one-dimensional homogeneous system of the Hopf-type equations arising in a two-fluid medium is considered. It is believed that energy dissipation occurs only due to the friction coefficient (analogous to Darcy) and the Cauchy data are given in the form of a finite trigonometric Fourier series...

A one-dimensional system of the Hopf-type equations is considered. Axial solutions to problems in the field of modeling two-fluid interactions are sought. A nonlinear system of ordinary differential equations is obtained. Direct and inverse problems for the obtained ODE are considered. A theorem on local solvability is proven.

We consider a one-dimensional inverse boundary value problem for a nonlinear system of the poroelasticity equations. We obtain estimates for the conditional stability of the inverse problem.

We consider a one-dimensional direct initial-boundary value problem for a nonlinear system of the poroelasticity equations. The theorem of local solvability of the classical solution to the problem is proved. The Frechet differentiability of the problem operator is proved, too.