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- Direcção, liderança e autonomia das escolasPublication . Silva, José ManuelO actual modelo de direcção e gestão das escolas e agrupamentos do ensino não superior operou uma rotura parcial com o figurino dominante pós revolução de 1974, cujas consequências ainda se está longe de alcançar em toda a sua plenitude. Após alguns ensaios nunca generalizados, a personalização da liderança administrativa e funcional assume, desde logo, um significado eminentemente simbólico, embora criando condições para que, a prazo, venham a ocorrer importantes mudanças, quer do ponto de vista organizacional, quer na forma como as escolas e agrupamentos se podem vir a relacionar com parceiros educativos e stakeholders, numa lógica de reforço da territorialização e da emergência de uma verdadeira cultura de prestação de serviços às comunidades onde aquelas se inserem. Associada à preocupação de sublinhar a liderança do director, acentua-se a importância do planeamento estratégico e este exige a clarificação dos limites e condições da autonomia das escolas e agrupamentos, o que, em última análise, acentua as contradições do modelo centralizado de administração do sistema escolar, vigente em Portugal.
- Experimental measurement of the mobilities of atomic, Ne+, and dimer, Ne2+, ions in NePublication . Garcia, A. N. C.; Trindade, A. M. F.; Oliveira, T. D. P.; Neves, P. N. B.; Barata, J. A. S.; Távora, L. M. N.; Dias, T. H. V. T.; Borges, F. I. G. M.; Conde, C. A. N.We measured the reduced mobilities of the atomic, Ne+, and dimer, Ne2+, ions in Ne, under different pressures and reduced electric fields, at 300 K. The value obtained for the atomic ion, 4.1 cm2V1 s1, is in good agreement with other values published in the scientific literature. The value obtained for the mobility of the dimer ion, 7.3 cm2 V1 s1, is not in accordance with other published data. We discuss the most probable sources of error.
- Photopeak shift effects due to the drift electric field in high pressure xenon detectorsPublication . Neves, P. N. B.; Barata, J. A. S.; Távora, L. M. N.; Dias, T. H. V. T.; Borges, F. I. G. M.; Conde, C. A. N.The photopeak shift in High Pressure Xe (HPXe) gamma ray detectors due to the energy acquired/lost by the photoelectric and Compton electrons, from the electric field applied in the drift region, is calculated using the PENELOPE code for gamma rays from several radioactive sources. The implications of this effect in HPXe detectors are discussed, namely for TPCs for double beta decay of 136 Xe studies.
- An Evolutionary Algorithm based on an outranking relation for sorting problemsPublication . Oliveira, Eunice; Antunes, Carlos HenggelerA new approach for using the preferences elicited from a Decision Maker (DM) into the operational framework of an Evolutionary Algorithm (EA) is presented. The preference representation is achieved using the parameters and principles of the ELECTRE TRI method devoted to the sorting problem. The outranking relation is used to replace the non-dominance relation in the usual operators in the EA (crossover, mutation and selection operator). The aim of this approach is to focus the search on the region of interest defined by the DM's preferences and consequently restrict the number of solutions in the Pareto-optimal front to be subject to further screening. This aspect is particularly important when dealing with problems that lead to a large number of non-dominated solutions.
- Promoting motivation and participation in higher education: A b-learning experiencePublication . Pereira, Isabel; Figueiredo, Antonio DiasA b-learning based pedagogical strategy is proposed to promote motivation and participation in higher education. It employs Open Space Technology (OST), collaborative activities, peer evaluation, individual reflection, and the sharing of a final purpose. OST lets the students group themselves according to their interest in a task and develops a mobilizing sense of belonging. A peer-evaluation phase is included, in which each group evaluates and gives suggestions to another group. The groups then produce the final versions of their work, which are presented at a final event whose format has been negotiated to strengthen motivation and shared commitment. The students are also expected to reflect individually on their own participation and learning during the course. The paper describes the pedagogical experiments that supported the development and validation of the strategy and explains why it had a positive impact on student participation and on the overall learning process.
- Efficient MV prediction for zonal search in video transcodingPublication . Marcelino, S.; Faria, S.; Assunção, P.; Moiron, S.; Ghanbari, M.This paper proposes a method to efficiently find motion vector predictions for zonal search motion re-estimation in fast video transcoders. The motion information extracted from the incoming video stream is processed to generate accurate motion vector predictions for transcoding with reduced complexity. Our results demonstrate that motion vector predictions computed by the proposed method outperform those generated by the highly efficient EPZS (Enhanced Predictive Zonal Search) algorithm in H.264/AVC transcoders. The computational complexity is reduced up to 59.6% at negligible cost in R-D performance. The proposed method can be useful in multimedia systems and applications using any type of transcoder, such as transrating and/or spatial resolution downsizing.
- Islanding operation of active distribution grids using an agent-based architecturePublication . Issicaba, D.; Gil, N. J.; Lopes, J. A. PeçasThis paper presents a decentralized architecture for the islanding operation of distribution grids with large volume of distributed generation. This architecture involves the definition of network blocks which share the responsibility of frequency control. The control block abstraction was particularly designed to support the transition from regular grids to smart grids. In addition, the control schemes were developed using an agentbased paradigm. Hence, an agent-based simulation platform was implemented using libraries from the Java Agent Development Framework (JADE). The control schemes were evaluated using a test system with different sorts of distributed energy resources and modeled in the EUROSTAG environment. Simulation results show the effectiveness of the control architecture when different failure events are applied to the test system.
- A dislexia no ensino superior: características, consequências e estratégias de intervençãoPublication . Mangas, Catarina; Sánchez, JoséContextualização das dificuldades de aprendizagem em geral e da dislexia no Ensino Superior em particular, exibindo o resultado de uma investigação que permitiu concluir que, globalmente as características dos alunos disléxicos os influenciam no Ensino Superior, uma vez que as dificuldades inerentes à dislexia resultam em consequências comportamentais, emocionais, sociais e académicas.
- Evaluation of soft possibilistic classifications with non-specificity uncertainty measuresPublication . Gonçalves, Luisa M. S.; Fonte, Cidália C.; Júlio, Eduardo N. B. S.; Caetano, MarioThe aim of this paper was to investigate the usefulness of non-specificity uncertainty measures to evaluate soft classifications of remote sensing images. In particular, we analysed whether these measures could be used to identify the difficulties found by the classifier and to estimate the classification accuracy. Two nonspecificity uncertainty measures were considered, the non-specificity measure (NSp) and the U-uncertainty measure, and their behaviour was analysed to evaluate which is the most appropriate for this application. To overcome the fact that these two measures have different ranges, a normalized version (Un) of the U-uncertainty measure was used. Both measures were applied to evaluate the uncertainty of a soft classification of a very high spatial resolution multispectral satellite image, performed with an object-oriented image analysis based on a fuzzy classification. The classification accuracy was evaluated using an error matrix and the user's and producer's accuracies were computed. Two uncertainty indexes are proposed for each measure, and the correlation between the information given by them and the user's and producer's accuracies was determined to assess the relationship and compatibility of both sources of information. The results show that there is a positive correlation between the information given by the uncertainty and accuracy indexes, but mainly between the uncertainty indexes and the user's accuracy, where the correlation achieved 77%. This study shows that uncertainty indexes may be used, along with the possibility distributions, as indicators of the classification performance, and may therefore be very useful tools.
- A Gastronomia e o Vinho como Factores Potenciadores de TurismoPublication . Oliveira, Simão; Méndez, Montserrat Díaz; Hita, Luís Marín