Stopping and merging problems for the porous media equation
نویسندگان
چکیده
A class of boundary value problems for nonlinear diiusion equations is studied. Using singular perturbation theory and matched asymptotic expansions, the author analyzes the interactions of compact-support solutions of the porous media equation with xed boundaries and with other solutions. The boundary layer analysis yields results on how \stopping" and \merging" disturbances at the interface propagate back into the solution. Analysis is also extended to cover merging problems for the fourth order lubrication equation.
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