Published online by Cambridge University Press: 27 July 2009
We define two new classes of multistate coherent systems by requiring, among other conditions, that their structure functions be Schur-concave (Schurconvex). The M + 1 performance levels of both the systems and their components are represented by the set [0, 1,…, M]. We present basic structural properties of the new classes. In particular, we study in some detail the number and form of the critical upper (lower) vectors to the various performance levels. We also present some probabilistic aspects of the new classes.