Abstract
Electrical Power Quality represents a challenging as much as attracting research topic nowadays, with consequences to all economic areas. Here, we studied the alternatives for reactive compensation in a residential low-voltage distribution grid using the Alternative Transient Program (ATP-EMTP). We developed a simulation model based on the results obtained from field measurements in a low voltage residential distribution grid with non-linear loads. We employed capacitors in different strategic places throughout the grid and changed their configurations, aiming to evaluate the technical viability of the application of reactive compensation. In this way, we investigated a methodology for the optimization of reactive compensation in secondary distribution grids, based on different solutions, in order to improve the voltage profile throughout the grid, as well as the technical losses that occur in a grid of this type. Next, we compared the simulated results with the field measurements. This analysis revealed that both approaches produced similar results, validating the simulation model. We therefore conclude that this model effectively reproduces the real linear and non-linear loads of the residential distribution grid and is suitable to be used in future studies. © 2011 IEEE.

Abstract
Power-Quality (PQ) is a crucial competitive and developing factor to all economic areas. The economic impact resulting from a bad PQ will be drastic to all consumers. Computers, uninterruptible power supplies (UPS), commuted power sources and fluorescent lamps/tubes are examples of nonlinear loads that have for main drawback the consumption of non-sinusoidal current. This paper presents a useful computer tool that can simulate and predict the behavior of non-linear loads and LV power systems with main focus on residential electrical grids. The paper also reviews some of the basic concepts and techniques related with power quality parameters and how they can be computed and presented in the simulation tool. The tool has an easy-to-use, friendly interface, and can be used as a tool to teach design techniques or as a laboratory to study the applicability of methods to real situations. The students can do simulations with their own data on Microsoft™ Windows® based platforms. © 2011 IEEE.

Abstract
Ever since the first studies about biomedical implantable devices, the problem of how to energize them has stood out as both important and notoriously difficult to solve. In order to extend the lifetime of implants, it is imperative to develop power generators that are autonomous, safe and maintenance-free. Energy harvesting is a natural way of meeting these requirements. First, the energy source is theoretically everlasting, a fact that helps to guarantee the autonomy. Second, the energy is obtained from the environment of the application itself, contributing to its safety. Finally, a properly designed energy harvesting system is very unlikely to ever require maintenance. This paper follows this line and describes an electromagnetic power transducer that harvests electrical energy from the human gait and stores it. An efficient power management module uses the stored energy to energize the telemetric system of a smart hip prosthesis implant, enabling the early detection of loosening, the target application of this work. The system is able to extract a total 1912.5 mu J of usable energy under normal walking conditions.

Abstract
Despite the benefits of precision agriculture and precision viticulture production systems, its adoption rate in the Portuguese Douro Demarcated Region remains low. One of the most demanding tasks in wine making is harvesting. Even for humans, the environment makes grape detection difficult, especially when the grapes and leaves have a similar color, which is generally the case for white grapes. In this paper, we propose a system for the detection and location, in the natural environment, of bunches of grapes in color images. The system is also able to distinguish between white and red grapes, at the same time, it calculates the location of the bunch stem. The proposed system achieved 97% and 91% correct classifications for red and white grapes, respectively.

Abstract
The rate of adoption of Precision Agriculture and Precision Viticulture production systems in the Douro Demarcated Region remains low. We believe that one way to raise it is to address challenging real-world problems whose solution offers a clear benefit to the viticulturist. For example, one of the most demanding tasks in wine making is harvesting. Even for humans, the detection of grapes in their natural environment is not always easy. White grapes are particularly difficult to detect, since their color is similar to that of the leafs. Here we present a low cost system for the detection of white grapes in natural environment color images. The system also calculates the probable location of the bunch stem and achieves 91% of correct classifications.

Abstract
In order to develop a flexible simulator, a variety of models for Ancillary Services (AS) negotiation has been implemented in MASCEM a multi-agent system competitive electricity markets simulator. In some of these models, the energy and the AS are addressed simultaneously while in other models they are addressed separately. This paper presents an energy and ancillary services joint market simulation. This paper proposes a deterministic approach for solving the energy and ancillary services joint market. A case study based on the dispatch of Regulation Down, Regulation Up, Spinning Reserve, and Non-Spinning Reserve services is used to demonstrate that the use of the developed methodology is suitable for solving this kind of optimization problem. The presented case study is based on CAISO real AS market data considers fifteen bids. © 2011 IEEE.