Let X be a Banach space, let A : D ( A ) ⊆ X → X be the infinitesimal generator of a C 0 -semigroup, let I be a nonempty, bounded interval and let K : I ↝ X be a given multi-valued function. By using the concept of A - quasi-tangent set introduced by Cârjă, Necula, Vrabie [O. Cârjă, M. Necula, I.I. Vrabie, Necessary and sufficient conditions for viability for a semilinear differential inclusions, Trans. Amer. Math. Soc., 361 (2009) 343–390; O. Cârjă, M. Necula, I.I. Vrabie, Viability, Invariance and Applications, North-Holland a Mathematics Studies, vol. 207, Elsevier, 2007] and using a tangency condition expressed in the terms of this concept, we establish a necessary and sufficient condition for mild viability referring to evolution inclusions of the form u ′ ( t ) ∈ A u ( t ) + F ( t , u ( t ) ) , where F is a multi-function defined on the graph of K . As applications, we deduce a sufficient condition for null-controllability and a comparison result for semilinear evolution inclusions.
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