We derive formulas for the Fréchet (singular) subdiferentials of the bilateral minimal time function T:Rn×Rn→[0,+∞]T:\mathbb{R}^n \times \mathbb{R}^n \to [0,+\infty] associated with a system governed by differential inclusions. As a consequence, we give a connection between the Fréchet normals to the sub-level sets of TT and to its epigraph. Finally, we show that the Fréchet normal cones to the sub-level set of TT at a point (α,β)(\alpha,\beta) and to epi(TT) at ((α,β),T(α,β))((\alpha,\beta),T(\alpha,\beta)) have the same dimension.

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Luong V. Nguyen

Institute of Mathematics, Polish Academy of Sciences, ul. Śniadeckich 8, 00-656 Warsaw, Poland

luonghdu@gmail.com
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L. V. Nguyen. “Variational Analysis for the Bilateral Minimal Time Function.” Journal of Convex Analysis 24 (2017), No. 3, 1029–1050. https://doi.org/10.68381/jca24062