In this paper, we give an overview of state-of-the-art Operations Research models and techniques used in passenger railway transportation. For each planning phase (strategic, tactical and operational), we describe the planning problems arising there and discuss some models and algorithms to...

We consider generalized monotone functions f: X -- {0,1} defined for an arbitrary binary relation = on X by the property x = y implies f(x) = f(y). These include the standard monotone (or positive) Boolean functions, regular Boolean functions and other interesting functions as special cases. It...