Assessment of the ensembles regional climate models in the representation of precipitation variability and extremes over Portugal

A new data set of daily gridded observations of precipitation, computed from over 400 stations in Portugal, is used to assess the performance of 12 regional climate models at 25 km resolution, from the ENSEMBLES set, all forced by ERA-40 boundary conditions, for the 1961-2000 period. Standard point error statistics, calculated from grid point and basin aggregated data, and precipitation related climate indices are used to analyze the performance of the different models in representing the main spatial and temporal features of the regional climate, and its extreme events. As a whole, the ENSEMBLES models are found to achieve a good representation of those features, with good spatial correlations with observations. There is a small but relevant negative bias in precipitation, especially in the driest months, leading to systematic errors in related climate indices. The underprediction of precipitation occurs in most percentiles, although this deficiency is partially corrected at the basin level. Interestingly, some of the conclusions concerning the performance of the models are different of what has been found for the contiguous territory of Spain; in particular, ENSEMBLES models appear too dry over Portugal and too wet over Spain. Finally, models behave quite differently in the simulation of some important aspects of local climate, from the mean climatology to high precipitation regimes in localized mountain ranges and in the subsequent drier regions.

ECG biometrics using a dissimilarity space representation

Electrocardiogram (ECG) biometrics are a relatively recent trend in biometric recognition, with at least 13 years of development in peer-reviewed literature. Most of the proposed biometric techniques perform classifi-cation on features extracted from either heartbeats or from ECG based transformed signals. The best representation is yet to be decided. This paper studies an alternative representation, a dissimilarity space, based on the pairwise dissimilarity between templates and subjects' signals. Additionally, this representation can make use of ECG signals sourced from multiple leads. Configurations of three leads will be tested and contrasted with single-lead experiments. Using the same k-NN classifier the results proved superior to those obtained through a similar algorithm which does not employ a dissimilarity representation. The best Authentication EER went as low as 1:53% for a database employing 503 subjects. However, the employment of extra leads did not prove itself advantageous.

An ontology-based representation of an agent-based controlled robotic cell

Dissertação apresentada na Faculdade de Ciência e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia Electrotécnica e de Computadores

Fractional Dynamics Representation in the Pseudo Phase Plane

Proceedings of the 10th Conference on Dynamical Systems Theory and Applications

A framework for supporting knowledge representation – an ontological based approach

Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores

Linked Data based Health Information Representation, Visualization and Retrieval System on the Semantic Web

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

Nominations across gender: An empirical investigation of Brazilian municipal elections

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

Cartographic representation of spatiotemporal phenomena

Dissertação para obtenção do Grau de Mestre em Engenharia Informática

Uncertainty, generalization, and neural representation of relevant variables for decision making

Dissertation presented to obtain the Ph.D degree in Biology, Computational Biology.

Staging the Scientist: The Representation of Science and its Processes in American and British Drama

Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Estudos Ingleses e Norte Americanos

A volumetric hybrid representation for obstacle detection in all-terrain robots

This dissertation presents an approach aimed at three-dimensional perception’s obstacle detection on all-terrain robots. Given the huge amount of acquired information, the adversities such environments present to an autonomous system and the swiftness, thus required, from each of its navigation decisions, it becomes imperative that the 3-D perceptional system to be able to map obstacles and passageways in the most swift and detailed manner. In this document, a hybrid approach is presented bringing the best of several methods together, combining the lightness of lesser meticulous analyses with the detail brought by more thorough ones. Realizing the former, a terrain’s slope mapping system upon a low resolute volumetric representation of the surrounding occupancy. For the latter’s detailed evaluation, two novel metrics were conceived to discriminate the little depth discrepancies found in between range scanner’s beam distance measurements. The hybrid solution resulting from the conjunction of these two representations provides a reliable answer to traversability mapping and a robust discrimination of penetrable vegetation from that constituting real obstructions. Two distinct robotic platforms offered the possibility to test the hybrid approach on very different applications: a boat, under an European project, the ECHORD Riverwatch, and a terrestrial four-wheeled robot for a national project, the Introsys Robot.

Relating the spatial component and users interests to improve applications based on questions, petitions and participatory processes

Nowadays, participatory processes attending the need for real democracy and transparency in governments and collectives are more needed than ever. Immediate participation through channels like social networks enable people to give their opinion and become pro-active citizens, seeking applications to interact with each other. The application described in this dissertation is a hybrid channel of communication of questions, petitions and participatory processes based on Public Participation Geographic Information System (PPGIS), Participation Geographic Information System (PGIS) and ‘soft’ (subjective data) Geographic Information System (SoftGIS) methodologies. To achieve a new approach to an application, its entire design is focused on the spatial component related with user interests. The spatial component is treated as main feature of the system to develop all others depending on it, enabling new features never seen before in social actions (questions, petitions and participatory processes). Results prove that it is possible to develop a working application mainly using open source software, with the possibility of spatial and subject filtering, visualizing and free download of actions within application. The resulting application empowers society by releasing soft data and defines a new breaking approach, unseen so far.

The Vase’s Representation (Cantharus, Crater) on the Roman Mosaic in Portugal: A Significant Formal and Iconographic Path from Classic Antiquity to Late Antiquity

11TH INTERNATIONAL COLLOQUIUM ON ANCIENT MOSAICS OCTOBER 16TH  20TH, 2009, BURSA TURKEY Mosaics of Turkey and Parallel Developments in the Rest of the Ancient and Medieval World: Questions of Iconography, Style and Technique from the Beginnings of Mosaic until the Late Byzantine Era

Popular music exhibitions in Portugal: practices of representation from 2007 to 2013

This thesis focuses on the representation of Popular Music in museums by mapping, analyzing, and characterizing its practices in Portugal at the beginning of the 21st century. Now that museums' ability to shape public discourse is acknowledged, the examination of popular music's discourses in museums is of the utmost importance for Ethnomusicology and Popular Music Studies as well as for Museum Studies. The concept of 'heritage' is at the heart of this processes. The study was designed with the aim of moving the exhibiting of popular music in museums forward through a qualitative inquiry of case studies. Data collection involved surveying pop-rock music exhibitions as a qualitative sampling of popular music exhibitions in Portugal from 2007 to 2013. Two of these exhibitions were selected as case studies: No Tempo do Gira-Discos: Um Percurso pela Produção Fonográfica Portuguesa at the Museu da Música in Lisbon in 2007 (also Faculdade de Letras, 2009), and A Magia do Vinil, a Música que Mudou a Sociedade at the Oficina da Cultura in Almada in 2008 (and several other venues, from 2009 to 2013). Two specific domains were observed: popular music exhibitions as instances of museum practice and museum professionals. The first domain encompasses analyzing the types of objects selected for exhibition; the interactive museum practices fostered by the exhibitions; the concepts and narratives used to address popular music discursively, as well as the interpretative practices they allow. The second domain, focuses museum professionals and curators of popular music exhibitions as members of a group, namely their goals, motivations and perspectives. The theoretical frameworks adopted were drawn from the fields of ethnomusicology, popular music studies, and museum studies. The written materials of the exhibitions were subjected of methods of discourse analysis methods. Semi-structured interviews with curators and museum professional were also conducted and analysed. From the museum studies perspective, the study research suggests that the practice adopted by popular music museums largely matches that of conventional museums. From the ethnomusicological and popular music studies stand point, the two case studies reveal two distinct conceptual worlds: the first exhibition, curated by an academic and an independent researcher, points to a mental configuration where popular music is explained through a framework of genres supported by different musical practices. Moreover, it is industry actors such as decision makers and gatekeepers that govern popular music, which implies that the visitors' romantic conception of the musician is to some extent dismantled; the second exhibition, curated by a record collector and specialist, is based on a more conventional process of the everyday historical speech that encodes a mismatch between “good” and “bad music”. Data generated by a survey shows that only one curator, in fact that of my first case study, has an academic background. The backgrounds of all the others are in some way similar to the curator of the second case study. Therefore, I conclude that the second case study best conveys the current practice of exhibiting Popular Music in Portugal.