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
In the scope of the reregulation process of the electric sector, both competitive pool markets and contract mechanisms at the generation and commercialization levels have been emerging. At the wholesale level, and apart from Pool structures and Bilateral Contracts, there are hybrid models in which these two types of structures coexist. In any case, the dispatch coming from the Pool Market Operator, prepared according to the buying and selling offers, together with the bilateral contracted powers must be analyzed from a technical point of view by an independent entity - System Operator. The System Operator aims at checking if the scheduled injected powers do not lead to a decrease of the security standards of the system. Taking in account this concern, in this paper we describe several models to perform the technical validation of sets of electricity schedules, namely trying to minimize the financial impact of the required changes on pre-scheduled generations and loads. This objective is modelled in terms of maximizing the satisfaction degree felt by the participants in the market. The developed application uses Simulated Annealing to solve the corresponding optimization problems. In Section IV of this paper we will include results obtained from several simulations in order to illustrate and demonstrate the interest of the referred models. © 2001 IEEE.

Abstract
In this paper we present a Monte Carlo based application to evaluate estimates of nodal marginal prices leading to target prices of transmission congestion contracts. The application integrates an optimization model to evaluate nodal marginal prices for each sampled state including an estimate of transmission losses. This formulation is integrated in a Monte Carlo simulation in order to deal with the probabilistic nature of component outages and to allow the user to represent load behavior using Load Duration Curves. The computational performance of the Monte Carlo simulation is enhanced by adopting a variance reduction acceleration technique based on a regression function. At a final section the paper includes results from a case study to illustrate the application of the model and to evaluate the efficiency of the referred acceleration technique. © 2001 IEEE.

Abstract
This paper describes the design of a multi-part mirror catadioptric vision system and its use for self-localization and detection of relevant objects in soccer robots. The mirror and associated algorithms have been used in robots participating in the middle-size league of RoboCup - The World Cup of Soccer Robots. (C) 2001 Published by Elsevier Science B.V.

Abstract
Simulation of the dynamic behaviour of liquid-liquid systems is of prominent importance in many industrial fields. Algorithms for fast and reliable simulation of single stirred vessels and extraction columns have already been published by some of the present authors. In this work, we propose a methodology to develop a parallel version of a previously validated sequential algorithm, for the simulation of a liquid-liquid Kuhni column. We also discuss the algorithm implementation in a distributed memory parallel-computing environment, using MPI. Despite the difficulties encountered to preserve efficiency in the case of a heterogeneous cluster, the results demonstrate performance improvements that clearly indicate that the approach followed may be successfully extended to allow real-time plant control applications.

Abstract
A MATLAB/SIMULINK-based simulator was employed for studies concerning the control of baker's yeast fed-batch fermentation. Four control algorithms were implemented and compared: the classical PID control, two discrete versions- modified velocity and position algorithms, and a fuzzy law. The simulation package was seen to be an efficient tool for the simulation and tests of control strategies of the nonlinear process.