Abstract
In this paper, the Unit Commitment (UC) problem is presented and solved, following an innovative approach based on a metaheuristic procedure. The problem consists on deciding which electric generators must be committed, over a given planning horizon, and on defining the production levels that are required for each generator, so that load and spinning reserve requirements are verified, at minimum production costs. Due to its complexity, exact methods proved to be inefficient when real size problems were considered. Therefore, heuristic methods have for long been developed and, in recent years, metaheuristics have also been applied with some success to the problem. Methods like Simulated Annealing, Tabu Search and Evolutionary Programming can be found in several papers, presenting results that are sufficiently interesting to justify further research in the area. In this paper, a resolution framework based on GRASP - Greedy Randomized Adaptive Search Procedure - is presented. To obtain a general optimisation tool, capable of solving different problem variants and of including several objectives, the operations involved in the optimisation process do not consider any particular characteristics of the classical UC problem. Even so, when applied to instances with very particular structures, the computational results show the potential of this approach.

Abstract
We propose an automated timetabling system for a typical situation in universities, where agents (usually departments or faculties) compete for a set of resources (lecture rooms) on a given number of time slots. Each agent uses its own algorithm (which might be unknown to the others). A central system decides whether some agent is granted a resource or not, based on a list of requests and on a certificate, obtained from each agent, asserting that it does not have requests with priority higher that a certain amount. Priority is measured primarily by the number of attendees and some requirements for particular features on the resources, but other criteria are proposed for ties. We describe a prototype implementation, in use at the Faculty of Sciences, University of Porto.

Abstract
This article presents the results of a qualitative study of a Portuguese bank regarding customer use of Internet banking integrated in a multi-channel offering that includes high street branches, telephone banking, and automatic teller machines. The results show that performance evaluation is a key factor influencing channel use. Customers tend to use the different service delivery systems in a complementary way, taking into account their assessment of the advantages and disadvantages of each one. Customer characteristics, and the type of financial operation, are also identified as important factors influencing this process. These results indicate that, in a multi-channel context, customer satisfaction with Internet services depends not only on the performance of this channel in isolation, but also on how it contributes to satisfaction with the overall service offering. © 2003, MCB UP Limited

Abstract
This article presents the results of a qualitative study of a multi-channel bank. It aims at developing new methods of gathering user requirements for web interfaces, joining HCI and Marketing perspectives. The results obtained so far indicate that, as most of financial operations are functionally available in the different service channels, experience requirements become increasingly important. In this context, essential use cases are particularly valuable in improving the process of gathering customer requirements. As they allow the analysis of users' interaction needs in a channel-independent way, their use can improve decisions on what services are best suited to each channel, to effectively address customer needs across different interaction modes, and make an efficient allocation of resources among channels.

Abstract
The commercial use of the Internet for service provision has deeply changed the environment where human-computer interaction takes place. Web interfaces are now integrated in overall service provision, and are designed for a huge and diversified set of potential users, in an uncontrolled context. With the aim of understanding customer interaction needs and improving the methods of requirements elicitation in the web context, a qualitative study of a multi-channel Portuguese bank was made. The results obtained so far indicate that Interaction Design and Services Marketing have strong complementarities. The Marketing perspective is especially useful with regard to the study of customer experience requirements, which are increasingly influential in customer decisions to adopt Internet services. Essential use cases are also very useful in the multiple platform service context, as they allow the elicitation of experience requirements in a technology-independent way, and therefore allow an integrated management of the different interaction channels.

Abstract
A large variety of techniques have been developed to solve or approximate the solution of multiattribute ranking problems. From such techniques, several implicit or explicit partial orders, defined on the same set of alternatives, are obtained (in many cases, by pairwise comparisons) with the goal of determining a linear order. Often, this goal is attained by assigning positive weights to each partial order relation. However, the imprecise judgments of the pairwise comparisons as well as other factors lead to inconsistencies which have been analyzed in an extensive literature devoted to this type of problem. In this paper, numerical results about linear extensions of weighted sum relations are applied to the recognition of pairwise imprecise judgments between alternatives as well as to the confirmation of a ranking solution as a linear extension of a quasi-order defined by a weighted sum of binary preference relations. (C) 2003 Wiley Periodicals, Inc.