Zu einigen Nachbarschaftsstrukturen fiir Iterationsverfahren zur naherangsweisen Lösung spezieller Reihenfolgeprohleme

Many discrete optimization. problems belong to the class of NP-hard problems. Therefore a number of approximation methods has been developed for these problems. As regards iteration methods, the determination of a suitable neighbourhood has a special importance. In this paper we consider various neighbourhood structures which can be used to solve such problems iteratively where the set of solutions is given by the set of permutations of m elements, Based on some introduced neighbourhood graphs, we state some properties of these structures