Abstract
Modeling discrete event systems with sequential behavior can be a very hard and complex task. Some formalisms are used in this context, such as: Petri Nets, Statecharts, Finite automata, Grafcet and others. Among these, Grafcet seems to be a good choice because it is easy: to learn, to understand and to use. Teaching Grafcet is then relevant within engineering courses concerned with Industrial Automation. A virtual laboratory, e-GRAFCET, developed and first tested in UTAD University; it is a new, easy-to-use multimedia e-educational tool to support the self-learning process of Grafcet. This paper, reports a study of e-GRAFCET use by the students of University of Minho. A questionnaire was prepared and students asked to fulfill it in a volunteer basis. The results were statistically analyzed and the scores compared. The overall objective is to understand how the tool helps students in their study, and consequently improve their learning off Grafcet, independently of their engineering background.

Abstract
Technologies employed in greenhouse production systems have been developed considerably during the recent decades. These improvements have taken place in many different research areas, such as the development of new covering materials and actuating equipments, modeling of the plant physiological processes and greenhouse climate, new cultural techniques, among many other topics. Although, due to economic and environmental increasing requirements there is still a need to improve the tools used for greenhouse management. At the present this work is being addressed with the emphasis on the economic optimization of the production process. This approach implies to know the influence of climate factors on production, as well the establishment of a good interface between engineers, physiologists and biologists. This paper presents the methods that are being implemented and tested with the aim of improving the climate management of a greenhouse located in the UTAD-University campus.

Abstract
This paper proposes a novel method for controlling the convergence rate of a particle swarm optimization algorithm using fractional calculus (FC) concepts. The optimization is tested for several well-known functions and the relationship between the fractional order velocity and the convergence of the algorithm is observed. The FC demonstrates a potential for interpreting evolution of the algorithm and to control its convergence.

Abstract
An adaptive greenhouse climate controller was implemented to regulate the air temperature, humidity and carbon dioxide concentration, with the aim of achieving set-point accuracy and reduce energy consumption. An optimization algorithm, based on the minimization of a cost function, was used to tune a Proportional-Integral-Derivative controller. The cost function is computed over a future time horizon of one hour as a function of the errors between the predicted and desired outputs and the predicted energy demand. Since the controller must be able to predict the greenhouse climate, it was needed to employ recursive identification algorithms to estimate in real-time the parameters of the climate model. When compared with commercially available controllers, this adaptive controller proved to have better performance regarding set-point accuracy and energy consumption.

Abstract
In this paper, deterministic and Artificial Neural Networks (ANNs) based techniques are applied to generate solar radiation forecasts with the purpose of being incorporated within a greenhouse predictive control strategy. These predictions are essential to estimate heat load fluctuations in the greenhouse caused by high frequency solar radiation changes, and so to improve ventilation and heating computation requirements for the greenhouse.

Abstract
Human pressure is pushing many of our natural resources to their limits in various regions of the world. Optimize their use is an urgent need. The management of agro-industry has been aware of that need, seeking to improve the productivity and reduce waste throughout the production process, as well by increasing the distribution efficiency of their products. Information and Communication Technologies (ICT) can support the control/management of the process inputs and outputs in various activities. This article attempts to describe a complete mushroom production chain. The information system developed by the agro-industry company studied allows to acquire, in real-time, the information about what is being produced (quantity and type of mushroom), which products are to be delivered to the different clients and which should be the planning for the next few days. © 2011 AISTI.