47 documents found, page 1 of 5
Comparison of RANS and LES turbulent flow models in a real stenosis
Lopes, D.; Puga, Hélder; Teixeira, J.; Lima, R.; Grilo, J.; Dueñas-Pamplona, J.; Ferrera, C.This study focuses on the performance of various turbulence models in predicting hemodynamic variables within a patient-specific geometry of the Brachiocephalic trunk exhibiting a severe stenosis. Numerical simulations employing Reynolds-averaged Navier-Stokes (RANS) and Large Eddy Simulation (LES) models were conducted, comparing four RANS with two LES models. Results indicated significant differences in turbu...
In vitro toxicity assessment of firefighters’ breathable air collected on polyu...
Bessa, M. J.; Teixeira, J.; Delerue-Matos, C.; Sarmento, B; Rodrigues, F.; Oliveira, M.Background: Occupational exposure as a firefighter has been recently classified as carcinogenic to humans (Group 1) by the International Agency for Research on Cancer (IARC) [1]. Polycyclic aromatic hydrocarbons (PAH) are one of the main fire-related pollutants [3], and their presence in the breathable air of firefighters was already demonstrated [4]. However, the toxicity mechanisms involved in such exposures ...
Design of low-profile transmitarray antennas with wide mechanical beam steering...
Vaquero, Á. F.; Teixeira, J.; Matos, S. A.; Arrebola, M.; Costa, J. R.; Felício, J. M.; Fernandes, C. A.; Fonseca, N. J. G.Mechanical beam steering using a single Transmitarray (TA) can be a cost-effective solution for a high-gain antenna with wide-angle scanning. Elevation scanning can be achieved by a linear displacement of the feed in the focal plane parallel to the aperture of diameter D. When designing compact terminals with a short focal length F and with high gain, the aberrations caused by this mechanical movement become th...
Reusable composite membranes for highly efficient chromium removal from real wa...
Queirós, Joana M.; Salazar, H.; Valverde, A.; Botelho, Gabriela; Fernández de Luis, R.; Teixeira, J.; Martins, P. M.; Lanceros-Méndez, S.Hexavalent chromium water contamination is still a worldwide concern because this highly mobile ion can cause carcinogenic effects on animals and humans. Therefore, there is an intense research on new active and cost-effective sorbents for Cr(VI), but most of them still exhibit a critical limitation: their powdered nature makes their recovery from water cost and energyconsuming. In this work, Cr(VI) nano-sorben...
What can genetics tell us about the history of a human-mediated introduction of...
Sequeira, F.; Aguilar, F. F.; Madeira, F. M.; Teixeira, J.; Crespo, E.; Ferrand, N.; Sampaio e rebelo, RuiThe golden-striped salamander is a streamside species endemic to the northwestern corner of the Iberian Peninsula. In the first half of the twentieth century, an undisclosed number of individuals of this species were reportedly captured in Buçaco, Central Portugal, and deliberately introduced in Sintra Mountains, 170 km south of its native distribution range. The discovery of a breeding population of this salam...
OPENCoastS: An open-access service for the automatic generation of coastal fore...
Oliveira, A.; Fortunato, A.B.; Rogeiro, J.; Teixeira, J.; Azevedo, A.; Lavaud, L.; Bertin, X.; Gomes, J.; David, M.; Pina, J.; Rodrigues, M.; Lopes, P.
Polarization-coded material classification in automotive LIDAR aiming at safer ...
Nunes-Pereira, E. J.; Peixoto, H.; Teixeira, J.; Simões, João Henrique Vivas SantosLIDAR sensors are one of the key enabling technologies for the wide acceptance of autonomous driving implementations. Target identification is a requisite in image processing, informing decision making in complex scenarios. The polarization from the backscattered signal provides an unambiguous signature for common metallic car paints and can serve as one-point measurement for target classification. This provide...
Conversão de edifícios existentes em nzeb através da integração de energias ren...
Estanqueiro, Ana; Joyce, A; Aelenei, Laura Elena; Facão, Jorge; Rodrigues, Carlos; Loureiro, David; Teixeira, J.; Correia, J.B.; Ramalho, ÁlvaroRESUMO: O Projeto IMPROVEMENT “Integration of combined cooling, heating and power microgrids in zero-energy public buildings under high power quality and continuity of service requirements” é um projeto financiado pelo Programa INTERREG SUDOE, de cariz marcadamente multidisciplinar e que reúne competências da área de integração e modelação de sistemas energéticos, da gestão de energia em edifícios, de energias ...
Dosing Device and Method of Operating the Dosing Device
Esteves, S.; Oliveira, L.; Teixeira, J.; Gonçalves, C.; Moreira, Pedro; Pinho, Olívia; Graça, Pedro
3D-Printed transmit-array antenna for broadband backhaul 5G links at V band
Matos, S.; Teixeira, J.; Costa, J. R.; Fernandes, C. A.; Nachabe, N.; Luxey, C.; Titz, D.; Gianesello, F.; Del Rio, C.; Arboleya-Arboleya, A.The low cost and compactness of transmit-array antennas (TAs) make them attractive for 5G backhaul links. However, the TA advantage is less obvious when considering the broadband operation requirement. Two main factors influence the bandwidth performance, namely: 1) the bandwidth of the unit cells, and 2) the number of 360° phase wrapping zones in the aperture, which are designed for a specific frequency. Herei...