Creat membership Creat membership
Sign in

Forgot password?

  • Forgot password?
    Sign Up
  • Confirm
    Sign In
home > search

Now showing items 1 - 16 of 141

  • Majority Logical Function Using a pi’npin a-SiC:H Structure1

    Silva, V.   Barata, M.   Louro, P.   Vieira, M.A.   Vieira, M.  

    Download Collect
  • Logic functions based on optical bias controlled SiC tandem devices

    Silva, V.   Vieira, M. A.   Vieira, M.   Louro, P.   Fantoni, A.   Barata, M.  

    The purpose of this paper is the design of an optoelectronic circuit based on a-SiC technology, able to act simultaneously as a 4-bit binary encoder or a binary decoder in a 4-to-16 line configurations and show multiplexer-based logical functions. The device consists of a p-i'(a-SiC:H)-n/p-i(a-Si:H)-n multilayered structure produced by PECVD. To analyze it under information-modulated wave (color channels) and uniform irradiation (background) four monochromatic pulsed lights (input channels): red, green, blue and violet shine on the device. Steady state optical bias was superimposed separately from the front and the back sides, and the generated photocurrent was measured. Results show that the devices, under appropriate optical bias, act as reconfigurable active filters that allow optical switching and optoelectronic logic functions development providing the possibility for selective removal of useless wavelengths. The logic functions needed to construct any other complex logic functions are the NOT, and both or either an AND or an OR. Any other complex logic function that might be found can also be used as building blocks to achieve the functions needed for the retrieval of channels within the WDM communication link. (C) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
    Download Collect
  • AND, OR, NOT Logical Functions in a SiC Tandem Device

    Silva, V.   Vieira, M.A.   Louro, P.   Barata, M.   Vieira, M.  

    Download Collect
  • Error rate analysis of M-PSK with magnitude modulation envelope control

    Silva, V.   Tomlinson, M.   Dinis, R.   Cercas, F.   Gomes, M.  

    Magnitude modulation (MM) envelope control is an efficient way of reducing the peak-to-average power ratio (PAPR) of single-carrier (SC) signals and improves an SC system's overall power efficiency. However, MM techniques reduce the PAPR at the cost of introducing distortion, highlighting a need to characterise the symbol error rate (SER) performance loss due to MM. This reported work focuses on the M-PSK case. An exact probability density function (PDF) based on the generalised extreme value distribution is proposed to model the statistical distribution of MM factors generated by MM techniques applied to SC constant amplitude constellations. By considering MM distortion as a form of fading, it is shown that this PDF may be used to derive an accurate union bound of the SER of M-PSK transmission on the additive white Gaussian channel channel when using MM envelope control.
    Download Collect
  • Lopes Gomes Da Silva v. Portugal

    Download Collect
  • Increased sensitivity in a-SiC pinpin multilayers in the VIS-NIR range under UV light

    Silva, V.   Rodrigues, I.   Vieira, M. A   Louro, P.   Vieira, M.  

    Download Collect
  • Prediction of Single Salt Rejection in Nanofiltration Membranes

    Silva, V.   Montalvillo, M.   Carmona, J.   Palacio, L.   Hernández, A.   Prádanos, P.  

    Download Collect
  • Logical functions in a tandem SiC device

    Silva, V.   Vieira, M.A.   Louro, P.   Barata, M.   Vieira, M.  

    This study demonstrates logical functions based on SiC technology. The device consists of a p-i'(a-SiC:H)-n/p-i(a-Si:H)-n heterostructure with low conductivity doped layers. Experimental optoelectronic characterization of the fabricated device is presented and shows the feasibility of tailoring channel bandwidth and wavelength by optical bias through illumination in the back and front sides with violet light. Two digital light signals are applied to the front side of the device while violet light steadily shines either at the back or front sides. Each digital light signal is composed by two wavelengths, one from the long and the other from the short visible wavelength range. One digital signal is the Red-Blue pair and the other the Green-Violet. The NOT logical function is shown with the Red-Blue pair likewise with the Green-Violet pair. The background biasing either at front or at the back side allows for an inverted signal or non inverted signal. Experimental results show and explain the interaction of two digital signal pairs and the identification of the logical AND, OR and XOR operations by the selection of the violet biasing illumination side. (C) 2014 Elsevier B.V. All rights reserved.
    Download Collect
  • Case of Salgueiro da Silva Mouta v. Portugal

    Presents information on the ruling of the European Court of Human Rights on a case regarding the violation of the right to respect for private and family life of Portuguese citizen Jo?o Manuel Salgueiro da Silva Mouta. Facts of the case; Complaints of Salgueiro da Silva Mouta; Details of the decision of the court.
    Download Collect
  • Posters * Demography, Epidemiology, Registries, and Health Economy

    Silva, V.   Pita Barros, P.   Lourenco, O.   Batel Marques, F.   Martinez-Salazar, J.   Palumbo, A.   De La Fuente, P.   Rodriguez, M.   Sanchez, F.   Lizan, C.   Marqueta, J.   Espallardo, O.   Lizan, L.   Polanco, C.   Paz, S.   Haagen, E. C.   Nelen, W. L. D. M.   Hermens, R. P. M. G.   Adang, E. M.   Grol, R. P. T. M.   Kremer, J. A. M.   Pinborg, A.   Hougaard, C. O.   Nyboe Andersen, A.   Kragh Andersen, P.   Boivin, J.   Schmidt, L.   Moolenaar, L.   Broekmans, F. B.   van de Veen, F.   Fauser, B. C. J. M.   Hompes, P.   Mol, B. W.   Porcu - Buisson, G.   Lehert, P.   Chabert - Orsini, V.   Giorgetti, C.   Shirkavand, A.   Sedigh Sarvestani, R.   Ezabadi, Z.   Omani Samani, R.   Silva Carvalho, J. L.   Santos, A.   Tabuas, I.   Braga, D. P. A. F.   Setti, A. S.   Figueira, R. C. S.   Queiroz, P.   Iaconelli, A.   Borges, E.   Fuldeore, M.   Wu, N.   Boulanger, L.   Chwalisz, K.   Marx, S.   Scaravelli, G.   De luca, R.   D\"Aloja, P.   Vigiliano, V.   Mayorga, J. M.   Bolli, S.   Spoletini, R.   Fiaccavento, S.   Monzo, A.   Flores, R.   Aniorte, S.   Rubio, J. M.   Peinado, I.   Pellicer, A.   Woodward, B. J.   Sohan, K.   Dahl, E.   Ziegler, A.   Horlbeck, S.   Strowitzki, T.   Eggert-Kruse, W.   Padhy, N.   Mahla, A.   Balasubramanyam, S.   Varma, T. R.   Yellamareddygari, S.   Willett, M. J.   Batra, S.   Farquhar, C.   Wang, Y. A.   Sullivan, A. E.  

    Download Collect
  • Extending displacement-based earthquake loss assessment (DBELA) for the computation of fragility curves

    Silva, V.   Crowley, H.   Pinho, R.   Varum, H.  

    This paper presents a new procedure to derive fragility functions for populations of buildings that relies on the displacement-based earthquake loss assessment (DBELA) methodology. The recent developments in this methodology are also presented herein, such as the development of new formulae for the calculation of the yield period or the consideration of infilled frame structures. In the fragility method proposed herein, thousands of synthetic buildings have been produced considering probabilistic distributions describing the variability in their geometrical and material properties. Then, their nonlinear capacity has been estimated using the DBELA method and their performance against a large set of ground motion records has been calculated. Global limit states are used to estimate the distribution of buildings in each damage state for different levels of ground motion, and a regression algorithm is applied to derive fragility functions for each limit state. The proposed methodology is demonstrated for the case of ductile and non-ductile Turkish reinforced concrete buildings with and without masonry infill walls, and compared with results obtained using nonlinear dynamic procedures and with the results from previous studies.
    Download Collect
  • Case of Matos e Silva, Lda. and others v. Portugal

    Download Collect
  • Quadtree based block merging algorithm for subband coding

    Silva, V.   de Sa, L.  

    In this paper an efficient video coding algorithm is described. It is based on a new quadtree block merging algorithm and wavelet decomposition of video signals using orthonormal and biorthogonal filter banks. The merging algorithm represents the motion compensated predicted images in a small set of rectangular regions in order to improve the coding efficiency and to minimize the border effects associated with the wavelet transform. Results of coding simulations using 8times8 and 16times16 blocks are presented. Also, subjects such as, choice of the optimal filter bank, boundary effects, quantization of the wavelet coefficients and filtering the prediction error by wavelet decomposition will be discussed
    Download Collect
  • Salgueiro Da Silva Mouta v. Portugal

    Difference in treatment in awarding parental responsibility dictated by factors related to sexual orientation of one parent was not permissible under the Convention.
    Download Collect
  • Isolation of\r Malassezia furfur\r from patients with onychomycosis

    Silva, V.   Moreno, G.-A.   Zaror, L.   De-Oliveira, E.   Fischman, O.  

    Download Collect
  • Analytical optimization of CQF filter banks

    Silva, V.   de Sa, L.  

    The optimization of subband filter banks for signal and image coding is normally dealt with by numerical means. It is shown that this optimization can be done analytically in the case of the prototype four-tap causal conjugate quadrature filter (CQF). The coding gain and aliasing energy are considered in the optimization. Using parametrizations of the prototype filter coefficients, it was found that the optimal filter is the regular Daubechies D 2 wavelet filter
    Download Collect
1 2 3 4 5 6 7 8 9


If you have any feedback, Please follow the official account to submit feedback.

Turn on your phone and scan

Submit Feedback