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2014
Guerreiro, B. J., C. Silvestre, R. Cunha, and A. Pascoal. "{Trajectory Tracking Nonlinear Model Predictive Control for Autonomous Surface Craft}." Transactions in Control Systems Technology. 22 (2014): 2160-2175. Abstract
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Guerreiro, B. J., C. Silvestre, R. Cunha, and A. Pascoal. "{Trajectory Tracking Nonlinear Model Predictive Control for Autonomous Surface Craft}." Transactions in Control Systems Technology. 22 (2014): 2160-2175. Abstract
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2013
Chemetov, N. V., and F. Cipriano. "The Inviscid Limit for the Navier-Stokes Equations with Slip Condition on Permeable Walls." JOURNAL OF NONLINEAR SCIENCE. 23 (2013): 731-750. Abstract

{We consider the Navier-Stokes equations in a 2D-bounded domain with general non-homogeneous Navier slip boundary conditions prescribed on permeable boundaries, and study the vanishing viscosity limit. We prove that solutions of the Navier-Stokes equations converge to solutions of the Euler equations satisfying the same Navier slip boundary condition on the inflow region of the boundary. The convergence is strong in Sobolev's spaces , which correspond to the spaces of the data.}

Chemetov, N. V., and F. Cipriano. "Boundary layer problem: Navier-Stokes equations and Euler equations." NONLINEAR ANALYSIS-REAL WORLD APPLICATIONS. 14 (2013): 2091-2104. Abstract

{This work is concerned with the boundary layer turbulence, which is an outstanding problem in fluid mechanics. We consider an incompressible viscous fluid in 2D domains with permeable walls. The permeability is described by the Yudovich condition. The goal of the article is to study the fluid behavior at vanishing viscosity (large Reynold's numbers). We show that the vanishing viscous limit is a solution of the Euler equations with the Yudovich condition on the inflow region of the boundary. (C) 2013 Elsevier Ltd. All rights reserved.}

Lavareda, G., A. de Calheiros Velozo, C. Nunes de Carvalho, and A. Amaral. "p/n junction depth control using amorphous silicon as a low temperature dopant source." THIN SOLID FILMS. 543 (2013): 122-124. Abstract

Phosphorus-doped amorphous silicon thin films, deposited at low temperatures by Plasma Enhanced Chemical Vapour Deposition were used as a dopant source on p-type c-Si substrates. A careful step of dehydrogenation was done in order to maintain the a-Si thin-film integrity. Subsequently, a fine-controlled drive-in of dopant, from the amorphous layer to the crystalline wafer was done, to form the p/n junction, using different time periods and temperatures. Dopant profiling in c-Si wafers as well as dopant concentration in a-Si: H films prior to diffusion, both measured by Secondary Ion Mass Spectrometry, are presented. Junction depths obtained are in the range of 98 nm to 2.4 mu m and surface concentrations are in the range of 1.1 x 10(21) to 4.3 x 10(20) at/cm(3). A dual diffusion mechanism explains the ``kink-and-tail{''} shape found for dopant profile. (C) 2013 Elsevier B.V. All rights reserved.

Lavareda, G., A. de Calheiros Velozo, C. Nunes de Carvalho, and A. Amaral. "p/n junction depth control using amorphous silicon as a low temperature dopant source." THIN SOLID FILMS. 543 (2013): 122-124. Abstract

Phosphorus-doped amorphous silicon thin films, deposited at low temperatures by Plasma Enhanced Chemical Vapour Deposition were used as a dopant source on p-type c-Si substrates. A careful step of dehydrogenation was done in order to maintain the a-Si thin-film integrity. Subsequently, a fine-controlled drive-in of dopant, from the amorphous layer to the crystalline wafer was done, to form the p/n junction, using different time periods and temperatures. Dopant profiling in c-Si wafers as well as dopant concentration in a-Si: H films prior to diffusion, both measured by Secondary Ion Mass Spectrometry, are presented. Junction depths obtained are in the range of 98 nm to 2.4 mu m and surface concentrations are in the range of 1.1 x 10(21) to 4.3 x 10(20) at/cm(3). A dual diffusion mechanism explains the ``kink-and-tail{''} shape found for dopant profile. (C) 2013 Elsevier B.V. All rights reserved.

de Calheiros Velozo, A., G. Lavareda, C. Nunes de Carvalho, and A. Amaral. "Thermal dehydrogenation of amorphous silicon: A time-evolution study." THIN SOLID FILMS. 543 (2013): 48-50. Abstract

A model is proposed to describe the decrease of H content in hydrogenated amorphous silicon (a-Si: H), during annealing at a fixed temperature. H content has been measured in several a-Si: H samples ( grown by plasma enhanced chemical vapor deposition) after being submitted to different annealing times at 400 degrees C. Obtained data has been fitted to the proposed model and initial diffusion coefficients of 3.2 x 10(-14) cm(2)/s for intrinsic films and 4.2 x 10(-14) cm(2)/s for n-type films were obtained. Reversely, H content evolution can be predicted during a thermal treatment if diffusion coefficients are previously known. (C) 2013 Elsevier B.V. All rights reserved.

de Calheiros Velozo, A., G. Lavareda, C. Nunes de Carvalho, and A. Amaral. "Thermal dehydrogenation of amorphous silicon: A time-evolution study." THIN SOLID FILMS. 543 (2013): 48-50. Abstract

A model is proposed to describe the decrease of H content in hydrogenated amorphous silicon (a-Si: H), during annealing at a fixed temperature. H content has been measured in several a-Si: H samples ( grown by plasma enhanced chemical vapor deposition) after being submitted to different annealing times at 400 degrees C. Obtained data has been fitted to the proposed model and initial diffusion coefficients of 3.2 x 10(-14) cm(2)/s for intrinsic films and 4.2 x 10(-14) cm(2)/s for n-type films were obtained. Reversely, H content evolution can be predicted during a thermal treatment if diffusion coefficients are previously known. (C) 2013 Elsevier B.V. All rights reserved.

Santos, J. P., J. P. Marques, A. M. Costa, M. C. Martins, P. Indelicato, and F. Parente. "Transition probability values of the 1s 22s3p 3P 0level in Be-like ions." Physica Scripta. T156 (2013): 014020. AbstractWebsite
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Santos, J. P., J. P. Marques, A. M. Costa, M. C. Martins, P. Indelicato, and F. Parente. "Transition probability values of the 1s 22s3p 3P 0level in Be-like ions." Physica Scripta. T156 (2013): 014020. AbstractWebsite
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Pé-Leve Santos, Sara C., Mariana Eloy Cruz, António M. E. Barroso, Catarina P. S. Fonseca, Mauro Guerra, Maria Luisa Carvalho, and Jose Paulo Santos. "Elemental characterization of plants and soils in Panasqueira tungsten mining region." Online (2013). AbstractWebsite
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Martins, Rodrigo F. P., Arman Ahnood, Nuno Correia, Luis M. N. P. Pereira, Raquel Barros, Pedro MCB Barquinha, Ricardo Costa, Isabel M. M. Ferreira, Arokia Nathan, and Elvira EMC Fortunato. "Recyclable, Flexible, Low-Power Oxide Electronics." Advanced Functional Materials. 23 (2013): 2153-2161. AbstractWebsite
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Araújo, Ricardo, Rui Castanhinha, Rui M. S. Martins, Octávio Mateus, Christophe Hendrickx, F. Beckmann, N. Schell, and L. C. Alves. "Filling the gaps of dinosaur eggshell phylogeny: Late Jurassic Theropod clutch with embryos from Portugal." Scientific Reports. 3 (2013). AbstractWebsite
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Cordas, Cristina M., Americo G. Duarte, Jose J. G. Moura, and Isabel Moura. "Electrochemical behaviour of bacterial nitric oxide reductase-Evidence of low redox potential non-heme Fe-B gives new perspectives on the catalytic mechanism." Biochimica Et Biophysica Acta-Bioenergetics. 1827.3 (2013): 233-238. Abstract
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Silva, Pedro C., Orestes J. Cerdeira, João M. Martins, and T. Monteiro-Henriques. "Data depth for the uniform distribution." Environmental and Ecological Statistics. 21 (2013): 27-39. AbstractWebsite
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Pina, J. M., P. Pereira, D. Valadas, J. M. Ceballos, and A. Alvarez. "Sand Pile Modeling of Multiseeded HTS Bulk Superconductors: Current Densities Identification by Genetic Algorithms." IEEE Transactions on Applied Superconductivity. 23.3 (2013): 8000804. AbstractWebsite

The sand pile model, in conjunction with Bean model, is often applied to describe single grain bulk superconductors. However, in several applications such as electric motors, multiseeded bulks are needed, due to the need to increase sample dimensions. In this paper, an extension of the sand pile model is presented in order to manage this type of materials. Multiseeded HTS bulk superconductors, produced, e.g., by the top-seeded melt growth process, are characterized by intra- and intergrain currents, and these are reflected in the model. However, identifying these currents from flux density measurements is not straightforward, when considering more than one grain. In fact, the number of currents increases with the number of grains, and these have to be identified from the measured field surface. A method to identify these currents based on genetic algorithms is validated with artificial data and then used in real measurements.

Neuparth, Nuno, Daniel Aelenei, Iolanda Caires, João Teixeira, João Viegas, Manuela Cano, Paula Leiria-Pinto, and Pedro Martins Environment and Health in Children Day Care Centers - Ambiente e Sa. Eds. Nuno Neuparth, Daniel Aelenei, Iolanda Caires, Joao Paulo Teixeira, Jo Viegas, Manuela Cano, Paula Leiria Pinto, and Pedro Martins. Universidade Nova de Lisboa, 1169-056 Lisboa: Faculdade de Ciências Médicas, 2013.Website
Guerreiro, B. J., C. Silvestre, R. Cunha, and A. Pascoal. "{Trajectory Tracking Nonlinear Model Predictive Control for Autonomous Surface Craft}." European Control Conference (ECC). 2013. 3006-3011. Abstract
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Guerreiro, B. J., C. Silvestre, R. Cunha, and A. Pascoal. "{Trajectory Tracking Nonlinear Model Predictive Control for Autonomous Surface Craft}." European Control Conference (ECC). 2013. 3006-3011. Abstract
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R, Igreja, Domingos H, Borges JP, and Dias CJ. "Enhancing the Response of Chemocapacitors with Electrospun Nanofiber Films." ADVANCED MATERIALS FORUM VI, PTS 1 AND 2. 730-732 (2013): 197-202. Abstract
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Cardoso, Alberto, Maria Teresa Restivo, Pedro Cioga, Miguel Delgado, J. Monsanto, João Bicker, Eduardo Nunes, and Paulo Gil. "flock.uc.pt – A Web Platform for Online Educational Modules with Online Experiments." International Journal of Online Engineering (iJOE). 9 (2013): 13-15. Abstract

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Gil, Paulo, Catarina Lucena, Alberto Cardoso, and Luís Palma. "Fuzzy controllers gains tuning: a constrained nonlinear optimization approach." Neural Computing & Applications. 22 (2013). Abstract

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Palma, Luís, J. Moreira, Paulo Gil, and Fernando Coito. "Hybrid Approach for Control Loop Performance Assessment." KES - IDT - 5th International Conference on Intelligent Decision Technologies. KES IDT 2013 - IOS Press - Frontiers of Artificial Intelligence and Applications (FAIA). 2013. 235-244. Abstract

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Palma, Luís, J. Cruz, Fernando Coito, and Paulo Gil. "Interactive Demonstration of a Java-Based Simulator of Dynamical Systems." 2nd Experiment@ International Conference. Exp@2013. 2013. Abstract

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