A method to compute various upper bounds for the Clar number (defined as the number of circles in a Clar formula) of a benzenoid hydrocarbon is given. Based...

Weber's problem consists in locating a facility in the plane in such a way that the weighted sum of Euclidean distances to <i>n</i> given points be minimum....

A hexagonal system is a connected plane graph without cut vertices in which each interior face is a regular hexagon. A linear algorithm is proposed to find ...

In many manufacturing systems, parts must be fed to automatic machines in a specific orientation. This is often accomplished by what are known as part orien...

A necessary and sufficient condition is given for the Clar graph and the inner dual of a benzenoid system to be equal. It is shown that <i>k &gt</i> 2 hexag...

This paper presents the first experiments undertaken with a stochastic programming model of gas contract portfolio management. This model is intended to be ...

There has been much recent statistical research in the area of inference under constraints. Here we consider the problem of bounded parameter estimation, in...

We investigate here the problems raised by the demand for quality. In particular, we show that the (inverse) demand, which yields the price the consumers ar...

In a first attempt to explain the good behavior of local improvement heuristics (such as Tabu Search and Simulated Annealing) for the <i>k</i>-coloring prob...

Given a two-way contingency table in which the rows and columns both define ordinal variables, the parameters are estimated by maximizing the likelihood fun...

A branch-and-bound algorithm is proposed for global minimization of indefinite quadratic functions subject to box constraints. Branching is done according ...

Approaches like infinitesimal perturbation analysis and the likelihood ratio method have drawn a great deal of attention recently, as ways of estimating the...

Interval arithmetic and Taylor's formula can be used to bound the slope of the cord of a univariate function at a given point. Such bounds for the function,...

The lattice structure of conventional linear congruential random number generators (LCGs), over integers, is well known. In this paper, we study LCGs in the...

A new heuristic algorithm, based on the Tabu Search methodology, is proposed for constrained redundancy optimization in series and in complex systems. It h...

A multiregional electricity supply and trading model, derived from MARKAL and involving four regions, is used to assess the advantages derived from a cooper...

We derive from Boolean methods a transformation which, when it can be applied, builds from a graph <i>G =</i> (<i>V,E</i>) a new graph <i>G'=</i> (<i>V',E'<...

Layout planning is an appropriate area in which to apply optimization models. A method is proposed here for evaluating general layouts (block layouts) when ...

For a weighted graph <i>G =</i> (<i>V,E</i>), the maximum weighted <i>k</i>-coloring problem is to color a set of vertices of maximum weight using <i>k</i> ...

Consider a network facility location problem where congestion arises at facilities, and is represented by delay functions that approximate the queuing proce...