Abstract
This paper presents a conceptual framework where the development of an information system for aggregate management of virtual / networked enterprises is taking place. Firstly, the general objectives of the system are described. An ontology based development approach is presented, assuming the role of conceptual guidance, both for the requirements analysis and design phases. Finally, a broad specification of aggregate management in this context is described through use cases.

Abstract
Due to their efficiency and their interesting design and implementation features, metaheuristics have been used for a long time with success, in dealing with combinatorial problems. In recent years they have been applied to the Unit Commitment problem with rather interesting results that justify further research in the area. In this paper we present a Simulated Annealing approach to the Unit Commitment problem. Two coding schemes are compared, new neighbourhood structures are presented and some searching strategies are discussed. Preliminary computational experience, performed on some test instances, shows that this approach is flexible, effective and able to handle variations on the problem structure. © 2001 IEEE.

Abstract
This paper describes the methods and experiences of developing of an information system in an industrial innovation context. The case analysed respects to a system supporting quality management tasks of working teams in industrial companies, developed within a research & development EU funded project. The initial concept of the system is described first, followed by the way how requirements where elicited and structured and the system specified. Next, design and prototyping are analysed , detailing the end-users evaluation approach. Conclusions are drawn on the opportunities and difficulties od R&D involving industrial enterprises.

Abstract
This paper presents a conceptual foundation for enterprise modelling from the social and organisational viewpoints. First, a method for the qualitative evaluation of enterprise modelling methods according to those viewpoints is presented. Next, the proposed approach of methodological mediation through a social and organisational conceptual core is outlined, and its implementation using the so called ontological engineering explained. Copyright (C) 2000 IFAC.

Abstract
The wastewater plumes show to be very difficult to observed in detail. The several studies already conducted exhibit very complex and patchy structures both in vertical and horizontal sections. It is not clear if this plume patchiness is due to physical processes or measurement limitations. Rapid tow-yo sampling is expected to reduce the time variability during and between transects. The AUVs may be a useful instrument to map and detect wastewater plumes. This paper presents several prediction studies using time series files of actual in-situ measurements integrated in a near field model. The model predictions of the plume characteristics at the end of near field support the definition of the best sampling strategy for an AUV monitoring mission in a Portuguese west coast outfall.

Abstract