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A perceção dos professores guineenses sobre a importância da língua portuguesa para o sucesso académico e profissional na Guiné-
Bissau
Publication . Sanhá, Anastácio Fernandes; Barreto, Maria Antónia Belchior Ferreira; Barbeiro, Luís Filipe Tomás
Este trabalho investiga a perceção de professores guineenses sobre a relevância da língua portuguesa para o sucesso académico e profissional na Guiné-Bissau, destacando o seu papel na formação identitária, educativa e socioeconómica do país. De caráter qualitativo, a investigação baseou-se em entrevistas semiestruturadas realizadas a oito docentes guineenses de diferentes níveis de ensino, uns encontram-se em Portugal, não obstante, outros a viver na Guiné-Bissau, visando compreender como o domínio do português influencia as trajetórias escolares e as perspetivas profissionais dos estudantes.O estudo analisa a língua enquanto pilar do desenvolvimento, abordando conceitos como língua
materna, segunda, nacional e oficial, e sublinhando a adoção histórica do português como língua oficial. Evidencia-se a sua função estratégica e os desafios decorrentes da diversidade linguística, sobretudo a influência do crioulo e das línguas étnicas no processo educativo. Apresenta-se ainda o panorama linguístico guineense, caracterizado pela coexistência do português com várias línguas nacionais e pela centralidade do crioulo como língua de comunicação quotidiana, embora não oficial. Discutem-se os efeitos das políticas coloniais, as dificuldades na implementação de alternativas linguísticas de ensino e a instabilidade sociopolítica que condiciona práticas educativas. No que respeita à formação docente, identificam-se lacunas significativas na preparação inicial e contínua, carência de recursos, insuficiente adoção de metodologias inovadoras e impacto dos contextos sociolinguísticos na prática pedagógica. Os professores reconhecem a centralidade do português para o êxito académico, a inserção profissional e a identidade
nacional, mas destacam dificuldades ligadas a interferências linguísticas, falta de formação e ausência de políticas bilíngues eficazes. Conclui-se que o fortalecimento do ensino do português é indispensável para promover inclusão social e desenvolvimento económico, exigindo políticas educativas integradas, valorização das línguas locais como apoio pedagógico e reforço da formação docente. Recomenda-se ainda a realização de estudos futuros que integrem outros atores educativos e a análise de políticas públicas com vista a práticas mais equitativas e inclusivas.
Asymmetric 3D video coding using regions of perceptual relevance
Publication . Pinto, Luis; Assunção, Pedro
This paper proposes an extension of the concept of asymmetric coding by introducing region-based asymmetry in the spatial dimension of stereoscopic video. The method relies on stereo image regions with different relevance for 3D perception defined by spatial binary masks. It is demonstrated that to a certain extent, regions with lower perceptual relevance can be encoded with lower quality than the remaining ones without harming the perceived quality. 3D video streams with different asymmetric quality combinations were produced and then evaluated through subjective testing. The results show that it is possible to further exploit traditional asymmetric coding while maintaining the same perceptual quality. Depending on the sequence content, this work leads to the conclusion that it is possible to reduce the bitrate of the auxiliary view up to 20 percent without being perceived by users.
Development of a new pultrusion equipment to manufacture thermoplastic matrix composite profiles
Publication . Novo, P.J.; Silva, J.F.; Van Hattum, F.W.J.; Marques, A.T.
This paper describes the design and manufacture of a low-cost full scale pultrusion prototype equipment and discusses the production and mechanical properties of polypropylene/glass (GF/PP) reinforced composite bars fabricated by using the prototype equipment. Three different GF/PP pre-impregnated raw-materials, a commercial GF/PP comingled system from Vetrotex, a GF/PP powder coated towpreg [1-3] and, a GF/PP pre-consolidated tape (PCT) produced in our laboratories, were used in the production of composite bars that were subsequently submitted to mechanical testing in order to determine the relevant mechanical properties and quantify the consolidation quality. Samples of the different composite profiles were also observed under SEM microscopy.
An iterative uncoupling technique for the identification of the dynamic properties of joints
Publication . Batista, F. C.; Maia, N.M.M.
The identification of the dynamic properties of joints is a very important subject in structural dynamics.
However, classic uncoupling methods are often very difficult to apply. In the present paper an iterative
technique is proposed, trying to circumvent the well-known ill-conditioning problems that arise due to any
small perturbations existing in the experimental data. Various cases are simulated and discussed to
illustrate the technique, including situations where it is not possible to take measurements on the joint
itself; the results are compared with the ones obtained with other methods.
On the optimal shape of hip implants
Publication . Ruben, Rui; Fernandes, Paulo R.; Folgado, João
The success of a total hip arthroplasty is strongly related to the initial stability of the femoral component and to the stress shielding effect. In fact, for cementless stems, initial stability is essential to promote bone ingrowth into the stem coating. An inefficient primary stability is also a cause of thigh pain. In addition, the bone adaptation after the surgery can lead to an excessive bone loss and, consequently, can compromise the success of the implant. These factors depend on prosthesis design, namely on material, interface conditions and shape. Although, surgeons use stems with very different geometries, new computational tools using structural optimization methods have been used to achieve a better design in order to improve initial stability and therefore, the implant durability. In this work, a multi-criteria shape optimization process is developed to study the relationship between implants performance and geometry. The multi-criteria objective function takes into account the initial stability of the femoral stem and the effect of stress shielding on bone adaptation after the surgery. Then, the optimized stems are tested using a concurrent model for bone remodeling and osseointegration to evaluate long-term performance. Additionally, the sensitivity to misalignments is analyzed, since femoral stems are often placed in varus or valgus position. Results show that the different criteria are contradictory resulting in different characteristics for the hip stem. However, the multi-criteria formulation leads to compromise solutions, with a combination of the geometric characteristics obtained for each criterion separately.