This Letter provides necessary and sufficient conditions on the excitation measurement pattern (EMP) that guarantee identifiability of a dynamical network has structure loop. The are extremely simple in their formulation, they can be checked by visual inspection. They allow one to easily characterize all EMPs make loop identifiable.

This paper deals with particular families of DC optimization problems involving suprema convex functions. We show that the specific structure this type function allows us to cover a variety in nonconvex programming. Necessary and sufficient optimality conditions for these are established, where some structural features conveniently exploited. More precisely, we derive necessary (global local) s...