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- TREINAR O PROCESSO DE DECISÃO EM SAÚDE USANDO SERIOUS GAMESPublication . Rosa, Marlene
- Cidadania da União: fator de união e de exclusãoPublication . Monteiro, Susana SardinhaA "constitucionalização" da cidadania da União pelo Tratado da União Europeia (TUE), em 1992, representou uma mudança no centro da gravidade de certos direitos de carácter público do homem europeu, e não já do homo economicus, do operador económico, elevando-o assim, ao status de um verdadeiro cidadão europeu.
- A reflection on explanatory factors for COVID -19: A comparative study between countriesPublication . Santos, E.; Oliveira, M. F.; Ratten, V.; Tavares, F.; Tavares, V.The COVID-19 pandemic is the biggest problem facing the world nowadays. Each country in the world has its own characteristics, which means that its governments, at different rhythms, adopt identical measures to combat this new virus. This article aims to perform a comparative study between countries with a population similar to the Portuguese in number of inhabitants and to find out which factors may explain the numbers registered with the COVID-19 pandemic. The results show that the countries that carried out more population tests have higher values in tourism, secu rity, innovation, competitiveness, and GDP per capita indicators. There is a significant and positive relationship between temperature and the daily cases of COVID-19 infections. The results found contribute to a greater knowledge of the behavior of this disease according to the characteristics of each country, making it useful for international business managers to compare and contrast different country environ mental conditions in order to define alternative strategies to overcome this great period of disturbance more quickly.
- Light field image coding with flexible viewpoint scalability and random accessPublication . Monteiro, Ricardo J. S.; Rodrigues, Nuno M. M.; Faria, Sérgio M. M.; Nunes, Paulo J. L.This paper proposes a novel light field image compression approach with viewpoint scalability and random access functionalities. Although current state-of-the-art image coding algorithms for light fields already achieve high compression ratios, there is a lack of support for such functionalities, which are important for ensuring compatibility with different displays/capturing devices, enhanced user interaction and low decoding delay. The proposed solution enables various encoding profiles with different flexible viewpoint scalability and random access capabilities, depending on the application scenario. When compared to other state-of-the-art methods, the proposed approach consistently presents higher bitrate savings (44% on average), namely when compared to pseudo-video sequence coding approach based on HEVC. Moreover, the proposed scalable codec also outperforms MuLE and WaSP verification models, achieving average bitrate saving gains of 37% and 47%, respectively. The various flexible encoding profiles proposed add fine control to the image prediction dependencies, which allow to exploit the tradeoff between coding efficiency and the viewpoint random access, consequently, decreasing the maximum random access penalties that range from 0.60 to 0.15, for lenslet and HDCA light fields.
- An interactive Web-GIS fluvial flood forecast and alert system in operation in PortugalPublication . Mourato, Sandra; Fernandez, Paulo; Marques, Fábio; Rocha, Alfredo; Pereira, LuísaFloods are one of the natural disasters not preventable, affecting people and causing significant damage to economic activities and infrastructures. Thus, it is of foremost importance to, within a disaster risk-reduction strategy, develop a useful flood forecast and alert system to prevent people from suffering flood disasters and mitigate its consequences. This article presents the Flood Forecast and Alert System in operational mode since 2019 for the Águeda river basin located in Portugal's centre region. This system is technologically advanced, differing from others since it uses a coupled real-time hydrologic and 2D hydrodynamic modelling supported on numerical weather prediction and a high-resolution digital terrain surface model. The system components are automatically activated and linked: i) a rainfall forecasting model (WRF), ii) a hydrological model (HEC-HMS), iii) a hydraulic model (HEC-RAS 2D), and a iv) Web-GIS platform. The hydrological model is forced with forecast precipitation for the next three days and updated every 6 h, which is crucial to generate pre-flood hazard maps. It also includes a Web GIS service for flood hazard dissemination available for civil authorities and citizens. A flood forecast and alert system is highly relevant to the community since, by enhancing knowledge, it provides the authorities responsible for assessing and managing the flood risk, responsiveness to disasters and timely decision-making, which is even more evident in the context of climate change.
- Distribution of the number of losses in busy-periods of oscillating Mx/G/1/(n,a,b) systemsPublication . Ferreira, Fátima; Pacheco, António; Ribeiro, HelenaWe analyze customer losses in busy-periods of preemptive and non-preemptive oscillating MX/G/1/(n,a,b) systems. Specifically, we propose a recursive scheme to compute the probability function of the number of customer losses in busy-periods of such systems. The effectiveness and usefulness of the proposed method is illustrated through the presentation of numerical examples that consider different arrival rates and service time and group size distributions.
- Cut-off for the legal ages in the Portuguese Population by Third Maturity Index: Measures of AccuracyPublication . Pereira, Cristiana Palmela; Rodrigues, Ana; Santos, Adriana; Salvado, Francisco; Santos, Rui; Cameriere, RobertoObjectives: The aim of this study is to estimate the cut-off points for the Portuguese legal ages through the I3M, and to compare them with the methods of Demirjian, Nolla and Moorrees. Design: The lower third molars were analyzed on 348 orthopantomography's aged between 12 and 23 years in a Portuguese Population. The images were analyzed by ImageJ and the cut-off points were calculated for the respective legal ages of 14, 16, 18 and 21 years old. Results: The correlation between age and the I3M was 0.862, whereas with Demirjian's stadiums, Nolla's stages, and Moorrees’ stages the correlation coefficients were 0.863, 0.842 and 0.844, respectively. For the cut-off point of 0.08 for the age of 18, a sensitivity of 78.99 %, specificity of 93.48 %, an accuracy of 88.54 %, a positive predictive value of 86.24 % and a posteriori Bayes probability of 92.82 %. The cut-off points established for the ages of 14, 16, 18 and 21 years for the Portuguese population achieved an accuracy of 83.67 %, 85.67 %, 88.54 % and 87.11 %, respectively. Conclusion: Demirjian's method and Cameriere's method attain quite similar results. In certain ages, the methods of Nolla and Moorrees show higher sensitivity or higher specificity when compared to Cameriere's method, however this last method is more stable in terms of reliability and more suitable to use in the Portuguese population.
- ‘Front’ And ‘Back Regions’ in Historic Housing Tourism: Spatial Segregation and Proximity in Host-Guest InteractionPublication . Braga, José Luís; Sousa, Bruno; Dionísio, MartaGoffman conceived a division of social establishments which he called region. A region for him was any place in some way limited by obstacles to perception. He distinguished two regions: ‘front’ and ‘back’. In turn, MacCannell applied Goffman’s classification to tourism. According to him, tourists show a special fascination with the ‘real lives’ of others. These ‘real lives’ can only be found in the back regions. MacCannell argued that, in the face of an influx of mass tourists, host communities seek to protect and isolate their culture by creating back regions. In these, the natives continue their significant traditions outside the eyes of tourists. Conversely, it is in the front regions that the natives perform a limited range of activities for tourist audiences. The tourism front region (or front stage) is, therefore, the place where hosts and guests meet and the tourism back region (or backstage) is the place where the hosts retreat, during the performance interval, to relax and prepare. This study aims to demonstrate the applicability of this concept to the interactions between hosts and guests that occur in Historic Housing Tourism (HHT). The results presented here emerged from a qualitative study in which 53 homeowners of HHT units were interviewed. The technique used for data collection and analysis was Grounded Theory (GT). In this study we found that, in the first phase of implantation of the HHT, which we called improvisation (1980s in most houses), the propensity for informalization was more evident. At this stage, there was a tendency to transform almost every region of the house in backstage. In the current phase of implementation of HHT, which we called the professionalization, formalization begins to acquire more and more importance. Hence, there is a tendency to erect more pronounced front regions and there is less fluidity between regions than in the improvisation phase. From the theory that we developed, using GT, two properties of HHT emerged which we named ‘segregating’ and ‘approaching’ that brought an empirical confirmation to Goffman’s theory. Spatial segregation is, thus, a means of preserving the intimacy of the HHT unit’s host family. In an interdisciplinary perspective, this study presents preliminary contributions in the management of historic housing tourism and tourism management (e.g. companies and destinations perspective).
- Data compression algorithms for biomedical imagesPublication . Faria, Sérgio; Cunha, Francisco; Parracho, João; Thomaz, Lucas; Assunção, PedroThe design of more efficient data structures, as well as the adoption of good information management practices applied to bioimage data, constitute very relevant initiatives. One such intervention is data compression and this text provides an overview and description of the main image compression methods, as well as an exposition of the potential of certain image formats according to specific application requirements, while ensuring the preservation of the data integrity.