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2010
Pereira, Pedro, Helena Fino, Fernando Coito, and Ventim M. Neves Automatic generation of RF integrated inductors analytical characterization. Symbolic and Numerical Methods, Modeling and Applications to Circuit Design (SM2ACD), 2010 XIth International Workshop on. Tunisia: IEEE, 2010.
Carvalho, G., R. Marques, A. R. Lopes, C. Faria, J. P. Noronha, A. Oehmen, O. C. Nunes, and M. A. M. Reis. "Biological treatment of propanil and 3,4-dichloroaniline: Kinetic and microbiological characterisation." Water Research. 44.17 (2010): 4980-4991.Biological Treatment of Propanil and 3,4-Dichloroaniline - Kinetic and Microbiological Characterisation 2010.pdf
Correia, Isabel, Stefan Nickel, and Francisco Saldanha-da-Gama. "The capacitated single-allocation hub location problem revisited: A note on a classical formulation." European Journal of Operational Research. 207 (2010): 92-96. Abstract

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Pereira, Pedro, Helena Fino, Fernando Coito, and Ventim M. Neves GADISI – Genetic Algorithms Applied to the Automatic Design of Integrated Spiral Inductors.. Doceis 2010. Caparica, Pt: Springer, 2010.
Nascimento, B., AG Batista, L. B. Alves, and M. D. Ortigueira. "MicroECG: An Integrated Platform for the Cardiac Arrythmia Detection and Characterization." EMERGING TRENDS IN TECHNOLOGICAL INNOVATION Book Series. IFIP Advances in Information and Communication Technology, 2010.
SCUTARU, G., F. SANDU, E. COCORADA, M. PAVALACHE, L. Gomes, F. Coito, A. K. MÖRSKY-LINDQUIST, S. CSEREY, M. DASCĂLU, V. NEUNDORF, and others RAPORT EDUCATIONAL., 2010. Abstract

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Santos, Pedro M. P., Alexandra Antunes, João Noronha, Eduarda Fernandes, and Abel J. S. C. Vieira. "Scavenging Activity of Aminoantipyrines Against Hydroxyl Radical." Journal of Medicinal Chemistry. 45 (2010): 2258-2264.Scavenging Activity of Aminoantipyrines Against Hydroxyl Radical.pdf
Queirós, R. B., J. P. Noronha, M. G. F. Sales, and González G. Aguilar. "Sensors for detection and quantification of bacterial contamination in waters for Human use." Advanced Engineering Materials. 12.5 (2010): 175-178.Sensors for the Detection and Quantification of Bacterial Contamination in Water for Human Use.pdf
Salema, Maria Isabel Gomes, Ana Paula Barbosa-povoa, and Augusto Q. Novais. "Simultaneous design and planning of supply chains with reverse flows: A generic modelling framework." European Journal of Operational Research. 203 (2010): 336-349. Abstract2010_salemabpovoanovais_ejor.pdfWebsite

The increase in societal awareness towards environmental issues has accrued the responsibility of goods producers, which at present came to encompass the entire product life cycle. Recently, the efficient design and operation of supply chains with return flows have, in particular, become a major challenge for many companies, given the high number of factors involved and their intricate interactions. In this paper, a multi-period and multi-product network model for the simultaneous design and planning of supply chains with reverse flows is proposed. A graph approach based on the conventional concepts of nodes and arcs is employed to model the network, where it is assumed that any network node is a transformation point of inbound into outbound flows, which in the limit may not differ, and that related arcs describe products flows along the chain. In here the formulation of time adopts a management perspective, i.e., the strategic design of the supply chain is dealt simultaneously with the tactical planning of its operation, which covers supply, production, storage and distribution. An example based on a Portuguese industry case is studied in order to validate both the applicability and adequacy of the model to real world problems.

Correia, Isabel, Stefan Nickel, and Francisco Saldanha-da-Gama. "Single-allocation hub location problems with capacity decisions and balancing requirements." International Conference on Mathematical and Computational Methods in Science and Engineering - Proceedings (2010): 51-56. Abstract

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Correia, Isabel, Stefan Nickel, and Francisco Saldanha-da-Gama. "Single-assignment hub location problems with multiple capacity levels." Transportation Research Part B: Methodological. 44 (2010): 1047-1066. Abstract

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Neagu, E. R., R. M. Neagu, C. J. Dias, M. C. Lanca, and J. N. Marat-Mendes. "The analysis of isothermal current in terms of charge injection or extraction at the metal-dielectric contact." Journal of Non-Crystalline Solids. 356 (2010): 833-837. AbstractWebsite

The measured isothermal charging and discharging currents are analyzed either in terms of polarization mechanisms or in terms of charge injection/extraction at the metal-dielectric interface and the conduction current through the dielectric material. We propose to measure the open-circuit isothermal charging and discharging currents just to overpass the difficulties related to the analysis of the conduction mechanisms through the dielectric materials. Besides a polarization current, there is a current related with charge injection or extraction at the metal-dielectric contact and a reverse current related to the charge trapped into the superficial trap states of the dielectric and that can jump at the interface in a reverse way. By fitting the experimental data, two important parameters can be determined (i) the highest value of the relaxation time for the polarization mechanisms still involved into the transient current and (ii) the height W-0 of the potential barrier at the metal-dielectric interface immediately after the step voltage is applied. Only the initial part of the measured isothermal charging or discharging current can be used to obtain information about the polarization processes. By transforming the time-domain data into the frequency domain, a maximum for the imaginary part of the dielectric permittivity is obtained, in good agreement with the data obtained from AC dielectric measurements and the finally thermally stimulated discharge current measurements. (C) 2009 Elsevier B.V. All rights reserved.

Neagu, E. R., R. M. Neagu, C. J. Dias, M. C. Lanca, and J. N. Marat-Mendes. "The analysis of isothermal current in terms of charge injection or extraction at the metal-dielectric contact." Journal of Non-Crystalline Solids. 356 (2010): 833-837. AbstractWebsite
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Correia, Natacha, Virgílio C. Machado, and Isabel L. Nunes Case Study “Estratégia de Aplicação de Ferramentas de Apoio à Gestão do Desempenho Humano em Ambientes Lean” [Case Study “Strategy for the Application of Tools for Supporting Human Performance Management in Lean Environments”]. Eds. P. Arezes, J. S. Baptista, M. P. Barroso, P. Carneiro, P. Cordeiro, N. Costa, R. Melo, A. S. Miguel, and G. P. Perestrelo. Occupational Safety and Hygiene (SHO10). Guimarães - Portugal: SPOSHO, 2010. Abstract
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Neagu, E. R., C. J. Dias, M. C. Lanca, R. Igreja, P. Inacio, and J. N. Marat-Mendes. "Charge Carriers Injection/Extraction at the Metal-Polymer Interface and Its Influence in the Capacitive Microelectromechanical Systems-Switches Actuation Voltage." Journal of Nanoscience and Nanotechnology. 10 (2010): 2503-2511. Abstract
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Neagu, E. R., C. J. Dias, M. C. Lanca, R. Igreja, P. Inacio, and J. N. Marat-Mendes. "Charge Carriers Injection/Extraction at the Metal-Polymer Interface and Its Influence in the Capacitive Microelectromechanical Systems-Switches Actuation Voltage." Journal of Nanoscience and Nanotechnology. 10 (2010): 2503-2511. AbstractWebsite

Opposite results concerning the sign of the parasitic charge accumulated at the metal dielectric contact in RF microelectromechanical systems (MEMS) capacitive switches are found in the literature. The mechanism concerning charge injection/extraction at the metal-dielectric contact and its influence on the pull-in voltage needs to be further clarified. A model-switch, for which only one dimension is in the microns range, is used to study the behaviour of a capacitive RF MEMS switch. The aim is to analyze how the electric charge is injected/extracted into or from the dielectric material under the applied field and to obtain realistic data to understand how this parasitic charge influences the pull-in voltage V-pi and the pull-off voltage V-po. A triangle voltage is employed to measure V-pi and V-po by measuring the isothermal charging/discharging currents. Our results demonstrate that V-pi is strongly dependent on the injected/extracted charge on the free surface of the dielectric. The charge injected/extracted at the bottom side of the dielectric has no influence on the actuation voltage. The charge injected/extracted on the free surface of the dielectric determines an increase of the modulus of V-pi and, eventually, the switch can fail to actuate. An estimation of the charge stored into the material was obtained (i) by measuring the charging current and the discharging current and (ii) from the value of the V-pi. The parasitic charge necessary to keep the bridge stick to the insulator is 5.3 x 10(-4) cm(-2) for our experimental conditions. The modification of the V-pi determined by the stored charge in the dielectric is analyzed. An increase of the relative dielectric permittivity by a factor of 2 produces a decrease of the actuation voltage of 10%. A variation of 30% in the elastic constant determines a variation of about 20% in the V-pi. A voltage threshold for charge injection/extraction was not observed.

Neagu, E. R., C. J. Dias, M. C. Lanca, R. Igreja, P. Inacio, and J. N. Marat-Mendes. "Charge Carriers Injection/Extraction at the Metal-Polymer Interface and Its Influence in the Capacitive Microelectromechanical Systems-Switches Actuation Voltage." Journal of Nanoscience and Nanotechnology. 10 (2010): 2503-2511. AbstractWebsite
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Araújo, J., P. V. Bünau, J. D. Mitchell, and M. Neunhöffer. "Computing automorphisms of semigroups." J. Symbolic Comput.. 45 (2010): 373-392. AbstractWebsite
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Lanca, M. C., M. Brandt, E. R. Neagu, C. J. Dias, and J. N. Marat-Mendes. "Dielectric spectra of natural cork and derivatives." Journal of Non-Crystalline Solids. 356 (2010): 763-767. AbstractWebsite

Cork is a cellular biomaterial that has unique characteristics that make it suitable for many types of applications. Since it is also an electrical insulator, the study of its electrical and dielectric properties can lead to new interesting applications. The moisture present in cork and derivatives has a very important role on the dielectric properties. In this work a composite made of both recycled cork and TetraPak (R) used containers was studied and compared with other cork products. The dielectric relaxation spectra of natural cork (as received), commercial cork agglomerate and of a composite cork/Tetrapak (R) was investigated in the temperature range of -50 to 120 degrees C and in the frequency range of 10(-1) Hz-2 MHz. For some samples of the composite a small amount of paraffin was added. The highest values for the imaginary part of the dielectric permittivity were found for the commercial material and the composite without paraffin. The lowest was found for the cork/TetraPak (R)/paraffin composite. The influence of humidity content was investigated for the composite with wax. Natural cork shows a peak around 80 degrees C (not seen in the derivative materials). The commercial agglomerate and the cork/TetraPak (R)/paraffin composite show a peak around 40-50 degrees C. In the composite this peak becomes smaller as humidity is removed. (C) 2009 Elsevier B.V. All rights reserved.

Lanca, M. C., M. Brandt, E. R. Neagu, C. J. Dias, and J. N. Marat-Mendes. "Dielectric spectra of natural cork and derivatives." Journal of Non-Crystalline Solids. 356 (2010): 763-767. Abstract
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Neagu, E. R., R. M. Neagu, C. J. Dias, M. C. Lanca, P. Inacio, and J. N. Marat-Mendes. "Electrical Method to Study the Weak Molecular Movements at Nanometric Scale in Low Mobility Materials." Advanced Materials Forum V, Pt 1 and 2. Eds. L. G. Rosa, and F. Margarido. Vol. 636-637. Materials Science Forum, 636-637. 2010. 430-436. Abstract

For the characterization of the new materials and for a better understanding of the connection between structure and properties it is necessary to use more and more sensible methods to study molecular movement at nanometric scale. This paper presents the experimental basis for a new electrical method to study the fine molecular movements at nanometric scale in dielectric materials. The method will be applied for polar and non-polar materials characterization. Traditionally, the electrical methods used to study the molecular movements are based on the movements of the dipoles that are parts of the molecules. We have proposed recently a combined protocol to analyze charge injection/extraction, transport, trapping and detrapping in low mobility materials. The experimental results demonstrate that the method can be used to obtain a complex thermogram which contains information about all molecular movements, even at nanoscopic level. Actually during the charging process we are decorating the structure with space charge and during the subsequent heating we are observing an apparent peak and the genuine peaks that are related to charge de-trapping determined by the molecular movement. The method is very sensitive, very selective and allows to determinate the parameters for local and collective molecular movements, including the temperature dependence of the activation energy and the relaxation time.

Neagu, E. R., R. M. Neagu, C. J. Dias, M. C. Lanca, P. Inacio, and J. N. Marat-Mendes. "Electrical Method to Study the Weak Molecular Movements at Nanometric Scale in Low Mobility Materials." Advanced Materials Forum V, Pt 1 and 2. Eds. L. G. Rosa, and F. Margarido. Vol. 636-637. Materials Science Forum, 636-637. 2010. 430-+. Abstract
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Faria, G., V. Lúcio, C. Chastre, and A. Nunes Estudo do comportamento à compressão de compósitos de madeira e cimento. Encontro Nacional Betão Estrutural 2010. Lisboa: LNEC, 2010. Abstract
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Santin, E., L. B. Oliveira, B. Nowacki, and J. Goes. "Fully integrated and reconfigurable architecture for coherent self-testing of IQ ADCs." Circuits and Systems (ISCAS), Proceedings of 2010 IEEE International Symposium on. IEEE, 2010. 1927-1930. Abstract
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