Abstract
In the 2005 Portuguese Parliament General Elections there were non-valid experiments of e-voting at five voting places and also through the Internet. Faculdade de Engenharia da Universidade do Porto audited such experiments. Relevant security, transparency, usability and accessibility evaluation criteria and sub-criteria were defined, and an auditing procedure based on AHP was established. This paper shortly presents the methodology used, the four e-voting systems and the main results of the overall experiment. The systems could be used successfully and were extremely popular with voters. However, more information to the citizens and to the officials involved in the e-voting process would be required for a valid election. The systems also need to be improved, for instance, to make sure that the number of votes electronically cast is the same as the number of voters that were validated and actually registered to vote at any particular site on the Election Day.

Abstract
This paper describes a case study concerning the teaching of logistics in the Computers and Electrical Engineering degree at FEUP. The logistics course is taken in the last semester of the degree and there are no lectures given by the teachers. All the learning strategy is based upon the autonomous learning capacity of the students, following the widespread citation of Confucius, ‘I hear and I forget. I see and I remember. I do and I understand’. The students are organized in groups and their autonomous work is motivated by the presentation that each group leader has to give every other week. A discussion period follows each presentation, and can be used by the teachers to evaluate the involvement of each member of the group and to complement the presentation whenever necessary. All the students are leaders at least once. The leaders are responsible for the group management and must prepare for the ‘leaders’ meeting', where the presentation session is organized. Assessment is based both on the quality of the presentation and on the technical correctness and completeness in the way subjects are treated and on leadership skills. While the teachers evaluate the two first issues, peers evaluate leadership. © 2004, Taylor & Francis Group, LLC.

Abstract
In this paper an application of constraint logic programming (CLP) to the resolution of nesting problems is presented. Nesting problems are a special case of the cutting and packing problems, in which the pieces generally have non-convex shapes. Because of their combinatorial optimization nature, nesting problems have traditionally been tackled by heuristics and in the recent past by meta-heuristics. When trying to formulate nesting problems as linear programming models, to achieve global optimal solutions, the difficulty of dealing with the disjunction of constraints arises. On the contrary, CLP deals easily with this type of relationships among constraints. A CLP implementation for the nesting problem is described for convex and non-convex shapes. The concept of nofit polygon is used to deal with the geometric constraints inherent to all cutting and packing problems. Computational results are presented. © 2003 Wiley Periodicals, Inc.

Abstract

Abstract
We address the short-term production planning and scheduling problem coming from the glass container industry. A furnace melts the glass that is distributed to a set of parallel molding machines. Both furnace and machine idleness are not allowed. The resulting multi-machine multi-item continuous setup lotsizing problem with a common resource has sequence-dependent setup times and costs. Production losses are penalized in the objective function since we deal with a capital intensive industry. We present two mixed integer programming formulations for this problem, which are reduced to a network flow type problem. The two formulations are improved by adding valid inequalities that lead to good lower bounds. We rely on a Lagrangian decomposition based heuristic for generating good feasible solutions. We report computational experiments for randomly generated instances and for real-life data on the aforementioned problem, as well as on a discrete lotsizing and scheduling version.

Abstract
Gupta and Magnusson [The capacitated lot-sizing and scheduling problem with sequence-dependent setup costs and setup times. Computers and Operations Research 2005;32(4):727-47] develop a model for the single machine capacitated lot-sizing and scheduling problem (CLSP) with sequence dependent setup times and setup costs, incorporating all the usual features of setup carryovers. In this note we show that this model does not avoid disconnected subtours. A new set of constraints is added to the model to provide an exact formulation for this problem.