Свойства нестационарных псевдовершин краевого множества при разрыве гладкости кривизны его границы в задаче Дирихле для уравнения типа эйконала

A number of properties of pseudo-vertices of a boundary value set in the Dirichlet problem to the first-order PDE of the eikonal type are revealed. Special points of the boundary of the boundary set responsible for the origin of the singularity of the generalized solution of the equation from the corresponding domain — the fundamental solution (according to S. N. Kruzhkov) in geometric optics or the minimax solution (according to A. I. Subbotin) in the theory of optimal control, are studied. In this paper, formulas for markers — numerical characteristics of pseudo-vertices are obtained. The formulas are found for the non-stationary case when the smoothness of the curvature of the boundary of the edge set is broken. The necessary conditions for the existence of pseudo-vertices are also derived in the form of relations generalizing the curvature stationarity conditions. The obtained results are illustrated by the example of building a solution to the velocity control problem.