• Coupling properties of directional couplers based on special waveguides 

  Rodríguez-Esquerre, Vitaly Félix; Oliveira, Ana Júlia Rodrigues Fernandes de; Costa, Matheus Silva; Souza, Lucas Uzêda (2013-05)

  The coupling characteristics of a novel kind of directional couplers composed by two parallel non-conventional waveguides are theoretically analyzed in details.The coupling length as a function of the operating wavelength ...
• A switchless multiband impedance matching technique based on multiresonant circuits 

  Silva, Fabrício G. S.; Lima, Robson Nunes de; Freire, Raimundo Carlos S.; Plett, Calvin (2013-07)

  In a number of applications, a matching network capable of providing specified impedances at different frequencies is necessary. In this brief, we present a novel technique for switchless multiband impedance matching ...
• Design and chromatic aberration analysis of plasmonic lenses using the finite element method 

  Mercedes, Cosme E. Rubio; Rodríguez-Esquerre, Vitaly Félix; Lima Junior, Ivan T.; Hernández-Figueroa, Hugo E. (2013)

  We designed plasmonic lenses and analyzed their chromatic aberration using the finite element method (FEM) in frequency domain with perfectly matched layers (PML). Plasmonic lenses permit subwavelength focusing of light ...
• Desenvolvimento de um tomógrafo ultrassônico para simulação do monitoramento dinâmico de injeção de CO2 em reservatórios de hidrocarbonetos 

  Oliveira, Amauri; Santos, Eduardo T. F. (Brasil, 2012-08)

  O principal objetivo deste artigo é apresentar o desenvolvimento de um tomógrafo ultrassônico que simula o monitoramento dinâmico da injeção de CO2 em um reservatório de hidrocarbonetos. É proposto o uso de tomografia ...
• Analysis of exact linearization and aproximate feedback linearization techniques 

  Schnitman, Leizer; Cardoso, Gildeberto de Souza (Brasil, 2011)

  This paper presents a study of linear control systems based on exact feedback linearization and approximate feedback linearization. As exact feedback linearization is applied, a linear controller can perform the control ...
• Multi-robot nonlinear model predictive formation control: moving target and target absence 

  Nascimento, Tiago Pereira do; Moreira, António Paulo; Conceição, André G. Scolari (2013)

  This paper describes a novel approach in formation control for mobile robots in the active target tracking problem. A nonlinear model predictive formation controller (NMPFC) for target perception was implemented to converge ...
• Analysis of the formation of a vinyltrimethoxysilane film on 1010 carbon steel using electrochemical techniques 

  Fernandes, Bruno Souza; Souza, Kleber Gustavo da Silva; Aoki, Idalina Vieira; Amado, Franco Dani Rico (2013)

  Purpose – The application of coatings on metal substrates can provide an increase in corrosion resistance in the environment where the material is employed. The use of silane causes low environmental impact and may represent ...
• Photosensitivity characterization of nanostructured tin oxide films and alternative photodetector application 

  Fontana, Márcio; Matias, Nilo; Costa, Fabiano Fragoso; Barros, Aiese Cruz; Oliveira, Amauri (2011-04)

  In this paper, we present an analysis of the photosensitivity property of electrical resistance of nanostructured porous tin oxide films (SnO2) deposited on Si substrates using a spray method. Based on this property, we ...
• A comparative analysis of Krylov Solvers for three-dimensional simulations of borehole sensors 

  Novo, Marcela S.; Silva, Luiz C. da; Teixeira, Fernando L. (2011-01)

  We perform a comparative analysis of three Krylov subspace methods, viz., the restarted generalized minimum residual (RGMRES), the conjugate gradient squared (CGS), and the stabilized biconjugate gradient (Bi-CGSTAB), for ...
• Decision support system for ultrasound inspection of fiber metal laminates using statistical signal processing and neural networks 

  Simas Filho, Eduardo Furtado de; Souza, Yure Nascimento de; Lopes, Juliana Lima da Silva; Farias, Cláudia Teresa Teles; Albuquerque, Maria Cléa Soares de (2013)

  The growth of the aerospace industry has motivated the development of alternative materials. The fiber–metal laminate composites (FML) may replace the monolithic aluminum alloys in aircrafts structure as they present some ...
• Artificial neural networks for the chromatic dispersion prediction of photonic crystal fibers 

  Rodríguez-Esquerre, Vitaly Félix; Lima, J. J. Isídio; Dourado-Sisnando, A.; Silva, F. G. Simões (2013-09)

  Multilayer perceptron artificial neural networks have been used for the efficient evaluation and prediction of the chromatic dispersion properties of microstructured optical fibers, with very low computational resources ...
• A set of novel modifications to improve algorithms from the A* family applied in mobile robotics 

  Nascimento, Tiago Pereira do; Costa, Pedro; Costa, Paulo G.; Moreira, António Paulo; Conceição, André Gustavo Scolari (2013)

  This paper presents a set of novel modifications that can be applied to any grid-based path planning algorithm from the A* family used in mobile robotics. Five modifications are presented regarding the way the robot sees ...
• Comments on “intelligent optimal control of robotic manipulator using neural networks” 

  Cerqueira, Jés J. F.; Jungbeck, Mario (2002)

  This note points out that the proof of Theorem 3 in Kim, Lewis, and Dawson (Automatica 36(9) 1355) has a mistake. Additionally, it is presented as the correction of the theorem.
• Transient response analysis and modeling of near wall flow conditions in a micro channel: evidence of slip flow 

  Neff, Helmut Franz; Lima, Antonio Marcus Nogueira; Loureiro, Fernanda Cecília Correia Lima; Almeida, Luiz Alberto Luz de (2007)

  An experimental tool for determination of the near wall transport parameters in a micro channel, supported by flow simulation, is presented. The method is based on the transient flow response due to convective diffusion, ...
• Aspects of the anodic behaviour of duplex stainless steels aged for long periods at low temperatures 

  Sousa, Carlos Alberto Caldas de; Kuri, Sebastião Elias; May, J. E. (2003)

  Duplex stainless steel samples were aged at low temperatures (300 and 400 °C) for 1000 and 2000 h. Their anodic behaviour was studied in a 0.1 N concentration of sulphuric acid, which revealed that the polarisation curves ...
• Fluid phase behavior modeling of CO2 + molten polymer systems using cubic and theoretically based equations of state 

  Arce, Pedro F.; Aznar, Martin; Silva, Silvana Mattedi e (2008)

  Phase equilibrium data of CO2 + molten polymer systems are of great relevance for chemical engineers because these are necessary for the optimal design of polymer final-treatment processes. This kind of processes needs ...
• Electron-hole transport and photovoltaic effect in gated MoS2 Schottky junctions 

  Fontana, Marcio; Deppe, Tristan; Boyd, Anthony K.; Rinzan, Mohamed; Liu, Amy Y.; Paranjape, Makarand; Barbara, Paola (Scientific ReportsBrasil, 2013)

  Semiconducting molybdenum disulfphide has emerged as an attractive material for novel nanoscale optoelectronic devices due to its reduced dimensionality and large direct bandgap. Since optoelectronic devices require ...
• Figures of merit and optimization of a VO 2 microbolometer with strong electrothermal feedback 

  Neto, Gilson; Lima, Antonio Marcus Nogueira; Khrebtov, Igor A.; Malyarov, Valery G.; Moreira, Cleumar S.; Almeida, Luiz Alberto Luz de; Neff, Helmut Franz (2008)

  The influence of electrothermal feedback and hysteresis on the operation conditions, noise, and performance of a VO2 transition-edge microbolometer has been evaluated. The material undergoes a first-order semiconductor-to-metal ...
• (A, B)-Invariance conditions of polyhedral domains for continuous-time systems 

  Dorea, Carlos Eduardo Trabuco; Hennet, J. C. (European Journal of Control, 1999)

  This paper provides an explicit characterisation of the (A,B)-invariance property of polyhedral sets with respect to linear continuous-time systems. A typical application of the concept of (A,B)-invariance is to investigate ...
• CMOS multiplier based on the relationship between drain current and inversion charge 

  Machado, M. B.; Cunha, A. I. A.; Lacerda, L. A. de; Galup Montoro, C.; Schneider, Marcio Cherem (2009)

  The authors propose a four-quadrant multiplier based on a core cell that exploits the general relationship between the saturation current of an MOS transistor and the source inversion charge density, valid from weak to ...

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