In order to understand the concentrating mechanism of the mammalian ki
dneys, it is necessary to study the relationship between the parameter
vector h (permeabilities of water and solutes) and the corresponding
vector of concentration profiles V. We consider the inverse problem: d
etermine h from a given V. This problem is ill-posed. Therefore, the r
egularization methods must be used to circumvent the ill-conditioning.
We show how the Levenberg-Tikhonov-Marquard method with the Sobolev n
orm can be used to handle the inverse problem.