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- Empresas comunicativas : um projecto de investigação em relações públicasPublication . Fernandes, J.L.; Ribeiro, Isabel
- O contributo dos descobrimentos na ampliação vocabular da língua portuguesaPublication . Pires, Natália AlbinoHoje em dia, parece bastante óbvio que toda e qualquer sociedade evolui graças aos contactos, quaisquer que sejam, que mantém com as demais sociedades. Assim, partindo deste pressuposto e de uma breve contextualização, ao longo do artigo pretende-se dar a conhecer algum do vocabulário, fruto de contactos mais ou menos prolongados entre portugueses e outros povos de além-mar, introduzido na Língua Portuguesa durante a diáspora.
- dAMUSE : a new tool for denoising and blind source separationPublication . Tomé, A.M.; Teixeira, Ana; Lang, E.W.; Stadlthanner, K.; Rocha, A.P.; Almeida, R.In this work a generalized version of AMUSE, called dAMUSE is proposed. The main modification consists in embedding the observed mixed signals in a high-dimensional feature space of delayed coordinates. With the embedded signals a matrix pencil is formed and its generalized eigendecomposition is computed similar to the algorithm AMUSE. We show that in this case the uncorrelated output signals are filtered versions of the unknown source signals. Further, denoising the data can be achieved conveniently in parallel with the signal separation. Numerical simulations using artificially mixed signals are presented to show the performance of the method. Further results of a heart rate variability (HRV) study are discussed showing that the output signals are related with LF (low frequency) and HF (high frequency) fluctuations. Finally, an application to separate artifacts from 2D NOESY NMR spectra and to denoise the reconstructed artefact-free spectra is presented also.
- Denoising using local projective subspace methodsPublication . Gruber, P.; Stadlthanner, K.; Böhm, M.; Theis, F.J.; Lang, E.W.; Tomé, A.M.; Teixeira, Ana; Puntonet, C.G.; Gorriz Saéz, J.M.In this paper we present denoising algorithms for enhancing noisy signals based on Local ICA (LICA), Delayed AMUSE (dAMUSE) and Kernel PCA (KPCA). The algorithm LICA relies on applying ICA locally to clusters of signals embedded in a high-dimensional feature space of delayed coordinates. The components resembling the signals can be detected by various criteria like estimators of kurtosis or the variance of autocorrelations depending on the statistical nature of the signal. The algorithm proposed can be applied favorably to the problem of denoising multi-dimensional data. Another projective subspace denoising method using delayed coordinates has been proposed recently with the algorithm dAMUSE. It combines the solution of blind source separation problems with denoising efforts in an elegant way and proofs to be very efficient and fast. Finally, KPCA represents a non-linear projective subspace method that is well suited for denoising also. Besides illustrative applications to toy examples and images, we provide an application of all algorithms considered to the analysis of protein NMR spectra.
- On the use of simulated annealing to automatically assign decorrelated components in second-order blind source separationPublication . Bohm, M.; Stadlthanner, K.; Gruber, P.; Theis, F.J.; Lang, E.W.; Tome, A.M.; Teixeira, Ana; Gronwald, W.; Kalbitzer, H.R.—In this paper, an automatic assignment tool, called BSS-AutoAssign, for artifact-related decorrelated components within a second-order blind source separation (BSS) is presented. The latter is based on the recently proposed algorithm dAMUSE, which provides an elegant solution to both the BSS and the denoising problem simultaneously. BSS-AutoAssign uses a local principal component analysis (PCA)to approximate the artifact signal and defines a suitable cost function which is optimized using simulated annealing. The algorithms dAMUSE plus BSS-AutoAssign are illustrated by applying them to the separation of water artifacts from two-dimensional nuclear overhauser enhancement (2-D NOESY) spectroscopy signals of proteins dissolved in water.
- De la especificidad de un corpus romancístico a la creación de una nueva aplicación : ULISSESPublication . Pires, Natália AlbinoEn esta comunicación pretendemos dar cuenta de cómo las singularidades de un corpus constituido por versiones del romancero de la tradición oral moderna portuguesa, un total de 1721 textos, nos han obligado a construir una nueva aplicación informática que respondiera a las necesidades y a los objetivos de nuestro trabajo de investigación; y, a continuación, describiremos la aplicación Ulisses, el IDE desarrollado específicamente para la anotación y análisis del corpus.
- ULISSES : un Integrated Development Environment desarrollado para la anotación de un corpus romancísticoPublication . Pires, Natália AlbinoUlisses es un Integrated Development Environment desarrollado para la anotación de un corpus constituído por romances de la tradición oral moderna portuguesa y que tiene la particularidad de poseer una estructura modular que admite la integración de nuevas herramientas y funcionalidades
- Figuras do discurso eleitoral nas presidenciais de 2006 : comunicação, participação política e deliberaçãoPublication . Baptista Ferreira, Gil
- Repensar o campo da educação de infânciaPublication . Coelho, AnaO presente artigo aborda o fenómeno da Educação da Infância, procurando enquadrar as reflexoões sobre as modalidades de cuidados e de educação das crianças pequenas no contexto mais vasto do debate actual acerca da infância e dos seus contextos. As funções e âmbitos da Educação da Infância são discutidos, e uma nova conceptualização dos serviços é analisada, procurando-se contribuir para o debate em torno da adopção de perspectivas mais integradas e abrangentes deste campo educativo.