Abstract
In this busy society of ours people push their limits to work better and more in order to remain competitive with their peers. Nonetheless, working longer hours does not necessarily improves productivity nor performance. In order to prevent the negative consequences of this increasing trend, the evolution of performance throughout the day of work should be more closely monitored. This could avoid undesirable states or even breakdowns, which have social and economical implications. In this work we measure user performance through their interaction with the computer. We monitor its evolution during a day of work and how different types of music may increase or decrease its natural daily degradation. We conclude that the relationship between types of music and its effects is not universal and depends, among other things, on the musical profile of the individual. A prototype for a distributed music recommendation service is presented that suggests musics at an individual and group level, based on user musical profiles and objectives.

Abstract
As a recently increasing trend among different applications of smart grid vision, smart households as a new implementation area of demand response (DR) strategies have drawn more attention both in research and in engineering practice. On the other hand, optimum sizing of renewable energy based small scale hybrid systems is also a topic that is widely covered by the existing literature. In this study, the sizing of additional distributed generation and energy storage systems to be applied in smart households, which due to DR activities have a different daily demand profile compared with normal household profiles, is investigated. To the best knowledge of the authors, this is the first attempt in the literature to consider the impact of DR on sizing. The study is conducted using a mixed-integer linear programming framework for home energy management system modeling and techno-economical sizing. Also, different sensitivity analyses considering the impacts of variation of economic inputs on the provided model are realized.

Abstract
The work reported in this paper introduces a periodic switching technique applied to continuous-time filters, whose outcome is an equivalent filter with scaled time-constants. The principle behind the method is based on a procedure that extends the integration time by periodically interrupting the normal integration of the filter. The net result is an up scaling of the time constant, inversely proportional to the switching duty-cycle. This is particularly suitable for reducing the area occupied by passive devices in integrated circuits, as well as to accurately calibrate the filter dynamics. Previous works have been following this concept in an entirely continuous-time perspective, either focusing on specific circuits or using approximations to provide an extended analysis. This paper includes input/output sampling to derive a closed-form representation for the scaling technique herein coined as 'Filter & Hold' (F&H). A detailed mathematical analysis is described, demonstrating that the F&H concept represents an exact filtering solution. Simulation results and experimental measurements are provided to further validate the theoretical analysis for an F&H vector-filter prototype. Copyright (C) 2014 John Wiley & Sons, Ltd.

Abstract
The goal of this project, one of the proposals of the EPS@ISEP Spring 2014, was to develop an Aquaponics System. Over recent years Aquaponics systems have received increased attention since they contribute to reduce the strain on resources within 1st and 3rd world countries. Aquaponics is the combination of Hydroponics and Aquaculture, mimicking a natural environment in order to successfully apply and enhance the understanding of natural cycles within an indoor process. Using this knowledge of natural cycles, it was possible to create a system with capabilities similar to that of a natural environment with the support of electronics, enhancing the overall efficiency of the system. The multinational team involved in the development of this system was composed of five students from five countries and fields of study. This paper describes their solution, including the overall design, the technology involved and the benefits it can bring to the current market. The team was able to design and render the Computer Aided Design (CAD) drawings of the prototype, assemble all components, successfully test the electronics and comply with the budget. Furthermore, the designed solution was supported by a product sustainability study and included a specific marketing plan. Last but not least, the students enrolled in this project obtained new multidisciplinary knowledge and increased their team work and cross-cultural communication skills.

Abstract
Nowadays, our lifestyle can lead to a scatter of focus, especially when we attend to several tasks in parallel or have to filter the important information from all the remaining one. In the context of a computer this usually means interacting with several applications simultaneously. Over the day, this significant demand on our brain results in the emergence of fatigue, making an individual more prone to distractions. Good management of the working time and effort invested in each task, as well as the effect of breaks at work, can result in better performance and better mental health, delaying the effects of fatigue. This paper presents a non-intrusive and non-invasive method for measuring distraction and fatigue in an individual and in a group of people. The main aim is to allow team managers to better understand the state of their collaborators, thus preparing them to take better decisions concerning their management.

Abstract
Technology is present in almost all aspects of our modern lives, and technological advances have been more and more prevalent. One would expect this to facilitate everybody's life, rendering common tasks more practical and easier to perform, but that is often not the case - at least not for the elderly. Older people have significant difficulties in using technological equipment due to the visual, physical, cognitive and hearing limitations associated with the natural aging process; these aspects must be taken into account if the intention is that of integrating technology in the lives of the elderly. In order to improve the quality of life of the elderly, as well as to prevent their social isolation, a mobile device application was developed to act as an intelligent remote control. This mobile application deals with data from two different platforms that were previously developed for improving the quality of life of the senior population: HbbTV and +Social. The features built into this virtual remote control include the integration with the +Social platform, as well as a speech recognition mechanism, and the possibility of making and receiving video calls with an integrated contacts list. A comprehensive study was carried out, focusing on recommendations and rules for graphical interfaces for the elderly, so as to allow equipping the application with adequate usability standards. The most relevant result was the definition of a list of guidelines used to steer the development of the interface. An investigation of mechanisms and technologies for enabling the implementation of the required functionalities was also carried out in order to define methodologies for freeing the user from the need of possessing any level of computer literacy. A series of usability tests was also performed to validate the viability of the remote control application. These tests allowed assessing the quality of the application, especially concerning the Graphical User Interface, as well as to receive feedback from potential end users. Based on the data collected during the test phase we conclude that this product is useful and that it responds to a current need.