“…Throughout this article, we refer to the penalty function proposed in [23] as a singular exact penalty function, since one achieves smoothness of this exact penalty function via the introduction of a singular term into the definition of this function. Recently, singular exact penalty functions have attracted a lot of attention of researchers [6,14,15,44], and were successfully applied to various constrained optimization problems [25,27,31,32,35,51,52]. It should be noted that the main feature of both smoothing approximations of exact penalty functions and singular exact penalty functions is the fact that they depend on some additional parameters apart from the penalty parameter.…”