Methodology for WSN communication technologies automated field tests

Wireless Sensor Networks(WSN) are networks of devices used to sense and act that applies wireless radios to communicate. To achieve a successful implementation of a wireless device it is necessary to take in consideration the existence of a wide variety of radios available, a large number of communication parameters (payload, duty cycle, etc.) and environmental conditions that may affect the device’s behaviour. However, to evaluate a specific radio towards a unique application it might be necessary to conduct trial experiments, with such a vast amount of devices, communication parameters and environmental conditions to take into consideration the number of trial cases generated can be surprisingly high. Thus, making trial experiments to achieve manual validation of wireless communication technologies becomes unsuitable due to the existence of a high number of trial cases on the field. To overcome this technological issue an automated test methodology was introduced, presenting the possibility to acquire data regarding the device’s behaviour when testing several technologies and parameters that care for a specific analysis. Therefore, this method advances the validation and analysis process of the wireless radios and allows the validation to be done without the need of specific and in depth knowledge about wireless devices.

A harmonização fiscal europeia

With this dissertation we aim to analyze the most relevant aspects of the excise duties harmonized regime, considering Community origins, but having also in attention all legal specifications of its implementation in Portugal. The legal regime of excise duties is presented as an ambitious theme, considering the challenge of different branches of law that influence this subject, such as Tax, Economic and Community laws, the inescapable influence of customs procedures, or regarding environmental objectives. In the European context, the harmonization of excise duties was seen as a condition for the implementation of the internal market, contributing to undo secular tax barriers between Member States and, since so, ensure fair competition and free movement of services and goods. Along with VAT, the excise duties harmonization process could represent a potential European tax system, essential for a full and integrated single market. In this context, it is essential to pay special attention to specific characteristics of excise duties regime, such as ‘duty suspension arrangement’ applicable during the production phase, storage and movement in certain conditions. The growing importance of excise duties, as for revenue or extra-fiscal purposes, recommends new academic studies on this subject, seeking new opportunities and challenges.

Cumprimento de ordens, obediência hierárquica e disciplina militar versus perpetração (in)voluntária de crimes

Following orders, hierarchical obedience and military discipline are essential values for the survival of the armed forces. Without them, it is not possible to conceive the armed forces as an essential pillar of a democratic state of law and a guarantor of national independence. As issuing orders as well as receiving and following them are inextricably linked to military discipline, and as such injunctions entail the workings of a particular obedience regime within the specific kind of organized power framework which is the Armed Forces, only by analysing the importance of such orders within this microcosm – with its strict hierarchical structure – will it be possible to understand which criminal judicial qualification to ascribe to the individual at the rear by reference to the role of the front line individual (i.e. the one who issues an order vs the one who executes it). That is, of course, when we are faced with the practice of unlawful acts, keeping in mind the organizational framework and its influence over the will of the executor. One thing we take as read, if the orders can be described as unlawful, the boundary line of the duty of obedience, which cannot be overstepped, both because of a legal as well as a constitutional imperative, will have been crossed. And the military have sworn an oath of obedience to the fundamental law. The topic of hierarchical obedience cannot be separated from the analysis of current legislation which pertains to the topic within military institutions. With that in mind, it appeared relevant to address the major norms which regulate the matter within the Portuguese military legal system, and, whenever necessary and required by the reality under analysis, to relate that to civilian law or legal doctrine.

Inclusão de crianças com paralisia cerebral no pré-escolar: perspetivas dos pais

Dissertação de mestrado em Educação Especial (área de especialização em Intervenção Precoce)

Implementation and comparison of different switching techniques for shunt active power filters

This paper presents a comparison between three switching techniques that can be used in three-phase four-wire Shunt Active Power Filters (SAPFs). The implemented switching techniques are: Periodic-Sampling (PS), Triangular Carrier Pulse-Width Modulation (TC-PWM) and Space Vector PWM (SVPWM). The comparison between them is made in terms of the compensated currents THD%, implementation complexity, necessary CPU time and SAPF efficiency. To perform this comparison are presented and analyzed several experimental results, obtained with a 20 kVA Shunt Active Power Filter prototype, specially developed for this purpose. The control system of the developed SAPF is based in the p-q Theory with a grid synchronization algorithm p-PLL.

Renewable energy system for an isolated micro grid

This paper presents the development of the power electronics needed for the interaction between the electrical generator of a wind turbine and an isolated ac micro grid. In this system there are basically two types of receptors for the energy produced by the wind turbine, which are the loads connected to the isolated micro grid and the batteries used to store energy. There are basically two states in which the system will work. One of the states is when there is enough wind power to supply the loads and the extra energy is used to charge the batteries. The other state is when there is low wind power and the batteries have to compensate the lack of power, so that the isolated micro grid has enough power to supply at least the priority loads. In this paper are presented the hardware and the control algorithm for the developed system. The topology was previously tested in computer simulations, using the software PSIM 9.0, and then validated with the implementation of a laboratory prototype.

Bidirectional battery charger with grid-to-vehicle, vehicle-to-grid and vehicle-to-home technologies

This paper presents the development of na on-board bidirectional battery charger for Electric Vehicles (EVs) targeting Grid-to-Vehicle (G2V), Vehicle-to-Grid (V2G), and Vehicle-to-Home (V2H) technologies. During the G2V operation mode the batteries are charged from the power grid with sinusoidal current and unitary power factor. During the V2G operation mode the energy stored in the batteries can be delivered back to the power grid contributing to the power system stability. In the V2H operation mode the energy stored in the batteries can be used to supply home loads during power outages, or to supply loads in places without connection to the power grid. Along the paper the hardware topology of the bidirectional battery charger is presented and the control algorithms are explained. Some considerations about the sizing of the AC side passive filter are taken into account in order to improve the performance in the three operation modes. The adopted topology and control algorithms are accessed through computer simulations and validated by experimental results achieved with a developed laboratory prototype operating in the different scenarios.

A escolha do direito aplicável ao mérito do litígio na arbitragem comercial internacional

Dissertação de mestrado em Direito dos Contratos e da Empresa

Development of high specific strength components, with internal cellular structure, for several applications

Dissertação de mestrado em Engenharia Mecânica

Utilização de gás natural comprimido em veículos pesados de passageiros

Dissertação de mestrado em Engenharia Mecânica

Racionalização e redução de custos das TIC na Administração Pública: o caso da PSP

Dissertação de mestrado integrado em Engenharia e Gestão de Sistemas de Informação

O direito de livre revogação nos contratos celebrados à distância e fora do estabelecimento comercial

Dissertação de mestrado em Direito dos Contratos e da Empresa

A celebração do contrato de seguro à distância

Dissertação de mestrado em Direito dos Contratos e da Empresa

A eficácia da Mediação Familiar no contexto das Responsabilidades Parentais

Dissertação de mestrado em Direito das Crianças, Família e Sucessões

The Irish Pub: past, present – whither the future?

The purpose of this research is to examine the main economic, legislative, and socio- cultural factors that are currently influencing the pub trade in Ireland and their specific impact on a sample of publicans in both Galway city and county. In approaching this task the author engaged in a comprehensive literature review on the origin, history and evolution of the Irish pub; examined the socio-cultural and economic role of the public house in Ireland and developed a profile of the Irish pub by undertaking a number of semi-structured interviews with pub owners from the area. In doing so, the author obtained the views and opinions of the publicans on the current state of their businesses, the extent to which patterns of trade have changed over recent years, the challenges and factors currently influencing their trade, the actions they believed to be necessary to promote the trade and address perceived difficulties and how they viewed the future of the pub business within the framework of the current regulatory regime. In light of this research, the author identified a number of key findings and put forward a series of recommendations designed to promote the future success and development of the pub trade in Ireland. The research established that public houses are currently operating under a very unfavourable regulatory framework that has resulted in the serious decline of the trade over the last decade. This decline appears to have coincided initially with the introduction of the ban on smoking in the workplace and was exacerbated further by the advent of more severe drink-driving laws, especially mandatory breath testing. Other unfavourable conditions include the high levels of excise duty, value added tax and local authority commercial rates. In addition to these regulatory factors, the research established that a major impediment to the pub trade is the unfair competition from supermarkets and other off-licence retail outlets and especially to the phenomenon of the below-cost selling of alcohol. The recession has also been a major contributory factor to the decline in the trade as also has been the trend towards lifestyle changes and home drinking mirroring the practice in some continental European countries.