Frequency hopping is a feature in GSM (Global System for Mobile Communications) cellular systems in which a frequency carrying the communication rapidly chan...

In this paper, we prove that the maximum <i>k</i>-club problem defined on an undirected graph is NP-hard. We also give an integer programming formulation f...

In a graph <i>G</i>, a <i>k-club</i> is a vertex set inducing a subgraph of diameter <i>k</i>. These structures play an important role in several applicati...

In this paper we derive lower bounds on the size of a minimum cover of a graph <i>G</i> by computing packings of edges, odd cycles and cliques of <i>G</i> o...

This paper describes strip sequencing models for large scale traveling salesman problems arising in flexible manufacturing operations in two or three discre...

It is well known that several combinatorial optimization problems can be nicely and readily modeled as an appropriate quadratic 0-1 function to be optimized...

This paper considers a flexible manufacturing system for several products, each requiring a number of sequential non-preemptive tasks, some of which may be...

Some earlier results on k-star constraints and comb inequalities are generalized.