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Compact 3D‐printed reflector antenna for radar applications at K‐band
Publication . Reis, João R.; Ribeiro, Carlos; Caldeirinha, Rafael F. S.
A compact parabolic reflector antenna aiming at radar applications in the K-band is presented. It is mainly composed of a thermoplastic material and using classical additive techniques (also known as 3D printing), the proposed high-gain antenna exhibits a novel and unique form factor, particularly of interest for applications with low payload capacity, for example unmanned aerial vehicles. The antenna is composed of four parts: (i) a paraboloid shape embodied in a supporting polylactic acid (PLA) material; (ii) a metallic coating applied to the paraboloid surface of (i), to enable it with electromagnetic reflecting properties; (iii) a PLA spacer that ensures the physical separation (i.e. focal distance) between parts (i) and (iv) and, finally, (iv) a microstrip patch antenna with a reduced ground plane to reduce feed blockage. Subsequently to an overview on the theoretical formulation of parabolic reflector antennas, an antenna targeting 20 dBi and a minimum bandwidth of 500 MHz operating in the 24 GHz ISM radar band have been dimensioned, optimised in CST Microwave Studio and validated against measurements performed on a physical prototype. The simulation and experimental results are in good agreement with the prototype yielding 18.3 dBi of gain and 2.2 GHz of useful bandwidth, clearly demonstrating the potential of the proposed antenna design.
Phenomena simulations for degradation prediction of cultural heritage buildings
Publication . Serrano, Francisco; Serrano, João; Ribeiro, Pedro; Gonçalves, Alexandrino; Grilo, Carlos; Rodrigues, Nuno; Hipólito-Correia, Virgílio
Predicting buildings degradation and erosion by natural and artificial phenomena has been an unexplored area. In this article is presented natural and artificial phenomena
simulations applied to a tridimensional model, using physics mechanics, created algorithms and using materials, which aims to be used to predict buildings level of destruction in the next years.
ICOHN25 – International Congress of Occupational Health Nursing: Proceedings
Publication . Chaves, Cláudia Margarida Correia Balula; Borges, Elizabete Maria das Neves; Melo, Elsa Maria de Oliveira Pinheiro de; Loureiro, Helena Maria Almeida Macedo; Gomes, José Herminio Gonçalves; Abreu, Margarida da Silva Neves de; Oliveira, Maria da Saudade Custódio Lopes; Queirós, Paulo Joaquim Pina; Barros, Teresa Madalena Kraus Brincheiro Hüttel; Fonseca-Pinto, Rui
Livro de resumos do 7.º Congresso ICOHN - International Congress of Occupational Health Nursing que decorreu em Leiria nos dias 2, 3 e 4 de abril de 2025.
Usability of Smartbands by the Elderly Population in the Context of Ambient Assisted Living Applications
Publication . Correia, Luís; Fuentes, Daniel; Ribeiro, José; Costa, Nuno; Reis, Arsénio; Rabadão, Carlos; Barroso, João; Pereira, António
Nowadays, the Portuguese population is aging at a fast pace. The situation is more severe in the interior regions of the country, where the rural areas have few people and have been constantly losing population; these are mostly elderly who, in some cases, live socially isolated. They are also often deprived of some types of social, health and technological services. One of the current challenges with respect to the elderly is that of improving the quality of life for those who still have some autonomy and live in their own residences so that they may continue living autonomously, while receiving the assistance of some exterior monitoring and supporting services. The Internet of Things (IoT) paradigm demonstrates great potential for creating technological solutions in this area as it aims to seamlessly integrate information technology with the daily lives of people. In this context, it is necessary to develop services that monitor the activity and health of the elderly in real time and alert caregivers or other family members in the case of an unusual event or behaviour. It is crucial that the technological system is able to collect data in a nonintrusive manner and without requiring much interaction with the elderly. Smartband devices are very good candidates for this purpose and, therefore, this work proposes assessing the level of acceptance of the usage of a smartbands by senior users in their daily activities. By using the definition of an architecture and the development of a prototype, it was possible to test the level of acceptance of smartbands by a sample of the elderly population—with surprising results from both the elderly and the caregivers—which constitutes an important contribution to the research field of Ambient Assisted Living (AAL). The evaluation showed that most users did not feel that the smartband was intrusive to their daily tasks and even considered using it in the future, while caregivers considered that the platform was very intuitive.
LDAShiny: An R Package for Exploratory Review of Scientific Literature Based on a Bayesian Probabilistic Model and Machine Learning Tools
Publication . De la Hoz-M, Javier; Fernández-Gómez, Mª José; Mendes, Susana
In this paper we propose an open source application called LDAShiny, which provides a graphical user interface to perform a review of scientific literature using the latent Dirichlet allocation algorithm and machine learning tools in an interactive and easy-to-use way. The procedures implemented are based on familiar approaches to modeling topics such as preprocessing, modeling, and postprocessing. The tool can be used by researchers or analysts who are not familiar with the R environment. We demonstrated the application by reviewing the literature published in the last three decades on the species Oreochromis niloticus. In total we reviewed 6196 abstracts of articles recorded in Scopus. LDAShiny allowed us to create the matrix of terms and documents. In the preprocessing phase it went from 530,143 unique terms to 3268. Thus, with the implemented options the number of unique terms was reduced, as well as the computational needs. The results showed that 14 topics were sufficient to describe the corpus of the example used in the demonstration. We also found that the general research topics on this species were related to growth performance, body weight, heavy metals, genetics and water quality, among others.