Browsing by Issue Date, starting with "2009-11"
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- Improving multiscale recurrent pattern image coding with least-squares prediction modePublication . Graziosi, Danillo B.; Rodrigues, Nuno M. M.; Silva, Eduardo A. B. da; Faria, Sérgio M. M. de; Carvalho, Murilo B. de; Faria, Sergio; M. M. Rodrigues, Nuno;The Multidimensional Multiscale Parser-based (MMP) image coding algorithm, when combined with flexible partitioning and predictive coding techniques (MMP-FP), provides state-of-the-art performance. In this paper we investigate the use of adaptive least-squares prediction in MMP. The linear prediction coefficients implicitly embed the local texture characteristics, and are computed based on a block’s causal neighborhood (composed of already reconstructed data). Thus, the intra prediction mode is adaptively adjusted according to the local context and no extra overhead is needed for signaling the coefficients. We add this new context-adaptive linear prediction mode to the other MMP prediction modes, that are based on the ones used in H.264/AVC; the best mode is chosen through rate-distortion optimization. Simulation results show that least-squares prediction is able to significantly increase MMP-FPs rate-distortion performance for smooth images, leading to better results than the ones of state-of-theart, transform-based methods. Yet with the addition of least-squares prediction MMP-FP presents no performance loss when used for encoding non-smooth images, such as text and graphics.
- Intercomprehension in primary school: discovering languages and constructing knowledgePublication . Barbeiro, LuísThis article discusses the potential value of developing pupils' intercomprehension skills at elementary school. This development construes Europe as a plurilingual and intercultural space in which the linguistic and cultural identity of each community finds its place. However, the construction of Europe also faces the challenges of assuring communication among people of different languages, promoting participation in an expanded community, and discovering other cultures in a perspective of mutual knowledge. The strategies of intercomprehension can serve the purposes of discovering plurilingualism and promoting comprehension skills among speakers of different languages, specifically among speakers of languages belonging to the same family. The proposals that are presented and discussed in this article originate from the Euromania project, a Socrates/Lingua project directed at the development of the intercomprehension skills of pupils within the group of Romance languages. The project's learning materials aim, on the one hand, at developing pupils' intercomprehension strategies in association with the learning of various school subjects; in this way, the mobilization of intercomprehension skills acquires an immediate purpose by serving the process of learning those subjects. On the other hand, the operations performed by pupils in order to reconstruct meaning convert their strategies into learning tools.
- On the computation of all supported efficient solutions in multi-objective integer network flow problemsPublication . Eusébio, Augusto; Figueira, José RuiThis paper presents a new algorithm for identifying all supported non-dominated vectors (or outcomes) in the objective space, as well as the corresponding efficient solutions in the decision space, for multi-objective integer network flow problems. Identifying the set of supported non-dominated vectors is of the utmost importance for obtaining a first approximation of the whole set of non-dominated vectors. This approximation is crucial, for example, in two-phase methods that first compute the supported non-dominated vectors and then the unsupported non-dominated ones. Our approach is based on a negative-cycle algorithm used in single objective minimum cost flow problems, applied to a sequence of parametric problems. The proposed approach uses the connectedness property of the set of supported non-dominated vectors/efficient solutions to find all integer solutions in maximal non-dominated/efficient facets.
- Interacção universidade-empresa : o portal Alumni como instrumento socialmente responsável e de design colaborativoPublication . Ferraz, Francisco António Vaz Guedes Delgado; Fernandes, Isabel Barreto; Schon, MichaelNovas preocupações sociais, económicas e ambientais têm originado novas condutas por parte das organizações e das instituições, numa perspectiva de alcançar objectivos sustentáveis a médio e longo prazo. Assim, as entidades referidas e em particular, as instituições de ensino, têm procurado desenvolver um conjunto de práticas e ferramentas que lhes permitam interagir com todas as entidades com as quais se relacionam, adoptando assim uma postura e um comportamento coerente e transparente, com objectivos de criação de valor, enquadrando-se estas práticas na temática da Responsabilidade Social. Dentro das várias práticas de Responsabilidade Social adoptadas pelas instituições indicadas, incluem-se algumas visando os Stakeholders externos mas outrora internos, nomeadamente os seus antigos alunos, ou seja, através da criação de uma ferramenta electrónica, denominada Portal Alumni. Neste documento, pretende-se efectuar uma análise sobre a potencialidade do Portal Alumni enquanto instrumento de Design Colaborativo e de Responsabilidade Social gerador do relacionamento entre as instituições de ensino superior e os seus antigos alunos, obtendo-se assim sinergias inter-relacionais benéficas a nível da empregabilidade dos alunos, da relação com as empresas, bem como a nível do branding da instituição educativa em causa.
- IC-Online história de um repositório institucionalPublication . Correia, Dulce; Marcos, Rosa
- Respeito e Salvaguarda: reflexões a partir de uma experiência no terreno da música rap de finais dos 90'sPublication . Fradique, TeresaA presente discussão desafia-nos no seu duplo centramento, quando nos propõe: contribuir para responder à pergunta ‘’O que fazem os antropólogos?’’ e tentar perceber de que forma os resultados da produção antropológica actual poderão entrar numa reflexão sobre a Convenção para a Salvaguarda do Património Cultural Imaterial (CSPCI).
- The partial average power as a fault diagnostic parameter applied to SRM drivesPublication . Gameiro, Natália S.; Cardoso, A. J. MarquesA new fault diagnostic parameter, applied to switched reluctance motor drives, is presented. The proposed parameter is a partial average power based on the power converter supply current and the rotor mechanical position information. At high speed operating conditions phase current is not regulated and the machine closed-loop control only needs to observe one current, which is the power converter supply current, in order to avoid excessive current amplitudes. The adopted control strategy is clearly explained. Several simulation results are presented and discussed considering different operating conditions. The normal operation, a fault occurrence in a power switch and a sudden mechanical load decrease are analysed. The simulation results permit to validate the proposed partial average power as an appropriate parameter for the diagnosis of an open-circuit fault in a power switch.
- Measuring the mobilities of the ions formed in P-10 mixturesPublication . Neves, P. N. B.; Trindade, A. M. F.; Barata, J. A. S.; de Oliveira Pegado de Noronha E Távora, Luís Miguel; Conde, C. A. N.We measured the reduced mobilities (k0 in cm2V -1s-1) of the ions that are formed in P-10 mixtures under different pressures and various reduced electric fields. Two types of ions were identified. We then used the extrapolated values of k0 when E/N→0 (2.41 and 2.76 cm2V-1s-1), the Langevin formula and the Blanc's law, to calculate the masses of these ions. Calculations indicate that the two ions have masses of 41 a.u. and 25 a.u., respectively. We propose hypothesis to explain the nature and origin of those ions.
- TraceMe - Indoor real-time location systemPublication . Silva, Pedro M. Mestre A.; Paralta, Maximino; Caldeirinha, Rafael; Rodrigues, Jorge; Serôdio, Carlos M.J.A.Localization of persons and objects is a current need of many industrial applications. Although in outdoor environments GPS or the cell-of-origin technique can have good results, they are very limited in indoor environments. In indoor environments other technologies such as RFID have a better performance.We propose an RFID based system, called TraceMe, to be used in real-time indoor localization. Besides localization it also enables area access control of people and objects, is able of alarm generation due to communications failure, access violation or tag violation, and is responsible for the interoperability of the deployed equipment. System specification, implementation, field tests and analysis of results are presented in this paper. As any traditional RFID system, it is constituted by Readers and Tags. The used tags are active and have the particularity of using two different communications frequencies. Besides the hardware also a Java-based middleware was developed. It is responsible to give meaning to data and to coordinate communications between all architecture elements. Final tests to the prototype were made in a public hospital.
- Crenças dos pais sobre o seu papel na parentalidade positivaPublication . Lopes, Saudade; Dixe, Maria dos Anjos; Catarino, Helena