Recently, Araujo and De la Pena (1998) gave bounds for the connectivity index of chemical trees as a function of this index for general trees and the ramifi...

We prove that amongst all fullerenes the dodecahedron has maximum smallest eigenvalue (equal to -<img src="G0234-1.gif" align=middle>), followed by the thre...

A survey is made of computer systems which help to obtain and sometimes provide automatically proofs, conjectures and refutations in graph theory.

This paper investigates a new variation in the continuous single facility location problem. Specifically, we address the problem of locating a new facility...

We study various uniform <i>k</i>-partition problems which consist in partitioning <i>m</i> sets, each of cardinality <i>k</i>, into <i>k</i> sets of cardin...

We survey computers systems which help to obtain and sometimes provide automatically conjectures and refutations in algebraic graph theory.

A generalization of the Roy-Gallai theorem on the chromatic number of a graph is derived which is also an extension of several other results of Berge and of...

We give characterizations of integral graphs in the family of complete split graphs and a few related families of graphs.

Variable neighborhood search (VNS) is a recent metaheuristic for solving combinatorial and global optimization problems whose basic idea is systematic chang...

This paper introduces a new kind of operational crew scheduling problem which consists in simultaneously modifying, as necessary, the existing flight depart...

Although airlines plan aircraft routes and crew schedules in advance, perturbations occur everyday. As a result, flight schedules may become infeasible and ...

Proposed just a few years ago, Variable Neighborhood Search (VNS) is a new metaheuristic for combinatorial and global optimization, based upon systematic ch...

This paper solves the problem of designing an access tree network for which the users are connected to the switches through SONET channels on fiber optics l...

This paper describes and solves the operational pilot scheduling problem for one day of operations. The problem consists in simultaneously modifying, as nec...

On the basis of a variable-neighbourhood search with the AutoGraphiX software, it is conjectured that for even numbers of atoms the fully conjugated acycli...

A generalization of the Roy-Gallai theorem is presented: it is based on the existence in any oriented graph of a stable set S such that for any node <i>w</i...

Maximum Clique is one of the most studied NP-hard optimization problem on graphs because of its simplicity and its numerous applications. A basic Variable N...

An algorithm with a complexity linear in the number of vertices is proposed for the computation of the Hyper-Wiener index of chemical trees. This complexity...

La Recherche à Voisinage Variable (RVV) est une métaheuristique récente basée sur l'idée d'un chargement systématique de voisinage, à la fois dans une phase...

Given a set of logical sentences and probabilities that these sentences are true, the probabilistic logic problem consists in determining whethe...