In this paper we present an amorphous silicon device that can be used in two operation modes to measure the concentration of ions in solution. While crystalline devices present a higher sensitivity, their amorphous counterpart present a much lower fabrication cost, thus enabling the production of cheap disposable sensors for use, for example, in the food industry. The devices were fabricated on glass substrates by the PECVD technique in the top gate configuration, where the metallic gate is replaced by an electrolytic solution with an immersed Ag/AgCl reference electrode. Silicon nitride is used as gate dielectric enhancing the sensitivity and passivation layer used to avoid leakage and electrochemical reactions. In this article we report on the semiconductor unit, showing that the device can be operated in a light-assisted mode, where changes in the pH produce changes on the measured ac photocurrent. In alternative the device can be operated as a conventional ion selective field effect device where changes in the pH induce changes in the transistor's threshold voltage.

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Would it be necessary to charge rapidly the electric vehicle (EV) and hybrid electric vehicle (HEV)? It is not easy to answer without a thorough look at the capability of the modern propulsion battery and the power necessities of the EV and HEV. The different possible solutions are compared and maximum speed of charging is analysed. The wired connection for charging is compared to the wireless energy transfer and because of the limitations imposed by the modern and future batteries, the contactless energy transfer is chosen as the future charging method.

The proposed regulation strategy consists in obtaining at the right time the correct information about the energy contained in the resonant tank. This information allows a stable operation of the switches and a higher efficiency of any Series Loaded Series Resonant (SLSR) power converter, especially when contactless energy transfer is concerned. The strategy is based on guaranteeing the correct portion of energy transported by the resonant tank to the load. The portion has to vary corresponding to the error signal taken from the output voltage and remains unchanged if the error signal is at its minimum. In a certain way this method is similar to the Current Mode Control of the classical power converters. The viability of the idea is demonstrated by simulation of a realistic analogue circuit (on preparation for a digital implementation in the near future).

Recent issues of global heating and energy shortages are imposing a need to change our paradigm around transportation. Somehow, electric vehicles are progressively standing as a strong and necessary alternative for the society. Technically and technologically the acceptance of the EV is easier now than ever but the psychology of the consumers and the running business of internal combustion vehicles, the whole existing infrastructure are too much conservative to be changed easily. The changes in technology require changes in the engineering society and its human resources. The objective of this paper is to give a contribution to the discussion and reflection of potential future scenarios where EV?HEV?s are spread across the society. It gives an overview of the range of knowledge and competences necessary for a sustainable and streamlined development of those. In fact, it is expected that a new kind of professional profiles need to be created or developed to supply the work market with the right human resources. The paper provides some discussion on the creation of new profiles or adaption of existing ones. Among different possible scenarios the creation of post-graduation courses for students holding undergraduate profiles in the fields referred to earlier would be an interesting and viable solution for fast response. The post graduation would be focused in specific key areas of the EV?HEV. Several factors are pointed out to endorse this scenario

The electromagnetic resonance became irreplaceable tool for wirelessly transfer energy and information. Since long this effect is widely used in communications but recently it is deeply studied and applied at the contactless transfer of energy. The electric?hybrid car battery charging is an urgent need and the knowledge about the resonant contactless transfer became very important. The study of the Series Loaded Series Resonant converter shows it as well suitable for the contactless energy transfer. The idealized Series Resonant Power Converter is used as a base for defining the best (most efficient) modes of operation. Based on the magnetic parameters of the loosely coupled transformer (magnetic link), the characteristics of the contactless power converter are described in approximated form, thus permitting an easier and faster calculation of the converter variables. This is used for instantaneous control of the converter, free from previously known defects.

This dissertation tries to track the route of power production from photovoltaic sources. A worldwide look into the photovoltaic solar power production is given. The theory behind the PV cell and its application in PV power modules is presented. The DC ? DC power converters usually associated with solar PV panels are showed. The main maximum power point tracking (MPPT) algorithms are also showed. A solar PV system was dimensioned using the theoretical models and the solar PV modules (BS ? 40) available at the Departamento de Engenharia Electrotécnica (DEE). This system was used as a reference for designing a simulator implemented in MatLab?Simulink. This simulator includes all the components needed to test the different MPP tracking algorithms. Those components are: A PV solar module, which can be associated with others to form a solar panel; A Flyback DC ? DC power converter and a classic perturb and observe (P&O) tracking algorithm. A solar power meter that gives values in W?m2 was built in order to validate simulation values of the solar PV modules. Measuring the solar module characteristics (tension ? current) and knowing the solar irradiation at that given time it is possible to check if the simulated values and the measured ones agree. With the data collected in the simulation a new MPP tracking algorithm was presented. This is based in the classic P&O algorithm, but using modules that try to overcome the local maxima problem. It also tries to minimize the control oscillations in the converter?inverter, this is done in order to minimize losses and to maximize power production.

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Research activities at European level on the concept of new working environments offers considerable attention to the challenges of the increased competencies of people working together with automated technologies. Since the decade of 1980 the development of approaches for the humanization of work organization, and for the development of participative organizational options induced to new proposals related to the development of complex and integrated automated systems. From such parallel conceptual development emerged the concept of “anthropocentric robotic systems” and quickly it covered also other fields of automation. More recently, the debate also covers issues related to working perception of people dealing with autonomous systems (e.g. Autonomous robotics) in tasks related to production planning, to programming and to process control. In fact, today one can understand the wider use of the anthropocentrism concept of production architectures, when understanding the new quality of these systems. In this chapter the author analyses the evolution of these issues related to governance of ICT applied to manufacturing and industrial services in research programmes strengthening very much the ‘classical’ concept of anthropocentric-based systems. It is emerging a new value of the intuitive capacities and human knowledge in the optimization and flexibilization of the manufacturing processes. While this would be a pre-condition to understand the human-robot communication needs, there is also a need to take into consideration the qualitative variables in the definition and design of robotic systems, jobs and production systems.

Nowadays, among the available transparent semiconductors for device use, the great majority (if not all) have n-type conductivity. The fabrication of a transparent p-type semiconductor with good optoelectronic properties (comparable to those of n-type: InOx, ITO, ZnOx or FTO) would significantly broaden the application field of thin films. However, until now no material has yet presented all the required properties. Cu2S is a p-type narrow-band-gap material with an average optical transmittance of about 60% in the visible range for 50 nm thick films. However, due to its high conductivity at room temperature, 10 nm in thickness seems to be appropriate for device use. Cu2S thin films with 10 nm in thickness have an optical visible transmittance of about 85% rendering them as very good candidates for transparent p-type semiconductors. In this work CuxS thin films were deposited on alkali-free (AF) glass by thermal evaporation. The objective was not only the determination of its optoelectronic properties but also the feasibility of an active layer in a p-type thin film transistor. In our CuxS thin films, p-type high conductivity with a total visible transmittance of about 50% have been achieved. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Nowadays, among the available transparent semiconductors for device use, the great majority (if not all) have n-type conductivity. The fabrication of a transparent p-type semiconductor with good optoelectronic properties (comparable to those of n-type: InOx, ITO, ZnOx or FTO) would significantly broaden the application field of thin films. However, until now no material has yet presented all the required properties. Cu2S is a p-type narrow-band-gap material with an average optical transmittance of about 60% in the visible range for 50 nm thick films. However, due to its high conductivity at room temperature, 10 nm in thickness seems to be appropriate for device use. Cu2S thin films with 10 nm in thickness have an optical visible transmittance of about 85% rendering them as very good candidates for transparent p-type semiconductors. In this work CuxS thin films were deposited on alkali-free (AF) glass by thermal evaporation. The objective was not only the determination of its optoelectronic properties but also the feasibility of an active layer in a p-type thin film transistor. In our CuxS thin films, p-type high conductivity with a total visible transmittance of about 50% have been achieved. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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