Abstract
This paper addresses the problem of parameter estimation of continuous-time systems using samples of its input-output data. We propose a method based on the bilinear transformation to obtain an equivalent discrete-time model. Introducing a new, polynomial pre-filter it is possible to compute the physical parameters via inverse mapping between the discrete-time and the continuous-time models. A simulation example is given to illustrate the noise effects in the parameter estimation results. Using experimental results, we demonstrate the ability of the estimator to handle real measurement problems.

Abstract
This paper describes a surveillance system for forest environments and protected natural areas with capacity for detecting fires and other ecological crimes. This system uses a digital camera that is controlled remotely by a system operator. Using the software the operator may chose to zoom a special spot or even take measures to place a strategy to fight the lire right before it becomes uncontrollable. Since that this system has to operate in the middle of forests, aspects like effectiveness, robustness and reliability are crucial. To make the positioning of camera, the system uses a stepper motor to the vertical movement of the camera, and a DC motor to the horizontal movement. The system also captures information about the temperature, humidity, wind speed and direction. All the processing is realized by a PIC16f877 microcontroller.

Abstract
The Pool, in many countries, was adopted for the participants of the electricity market to trade the electrical energy in a basis of each half-hour or one hour of the next day. However, like the traditional markets, the agents of electrical market are now exposed to the volatility of market price. In some countries, to face that problem and to turn the market more liquid, the derivatives markets - futures and options - were introduced to negotiate products with electrical energy as underlying active. In this context, there is a need of decision-support tools to assist those agents for the use of derivatives markets with the objective of practicing the hedge. In this paper, we present a decision model that supports producers to establish contracts with the objective to maximize the profit expected utility. © 2003 IEEE.

Abstract
This paper deals with some disturbances that reach the electric power systems. These problems originated some interest due to the changes of the electric loads characteristics, which were predominantly electromechanical and today are predominantly non-linear. This is due to the electronic systems involved. Results of some measurements performed in electric grid of the Oporto Engineering Faculty Campus and in the University of Vila Real (UTAD) are presented and some solutions that had been implemented for the related problems minimization are also described.

Abstract
In deregulated electrical systems, production schedule for power plants is the result of an auction process. In the Spanish case, this schedule includes two main concepts: energy production (to be actually produced) and secondary reserve (to maintain available). The generation company faces the problem of converting energy schedule into a power schedule, respecting the reserve schedule as well as technical constraints, and trying to accomplish different goals: to minimise the production costs, to obtain smooth shapes for the power schedules and to optimise eventual compensation in schedules. A weighted goal mixed integer programming model with a real-size application to deal with this problem is presented.

Abstract
The aim of this work was the development of a new approach to find an optimal solution for the internal electrical network configuration of a wind park. The new approach, described in this paper, allows solving the electrical design problem of a wind park, trying to find simultaneously the best topology for the network and for the cable speciifciations. The problem is considered as a global optimization problem (minimisation of the investments and operation costs), in which reliability is also taken into account. For that purpose, an evolutionary approach based on nitching type methods was used to develop a design tool able to find a reduced set of good solutions to be presented to the design engineers for further decision. This approach was tested with success in the project of a real wind park and the results proved to be satisfactory.