Entradas recentes
Absolute dating of construction materials and petrological characterisation of mortars from the Santalla de Bóveda Monument (Lugo, Spain)
( 2023 ) Blanco-Rotea, Rebeca; Sanjurjo‑Sánchez, Jorge; Freire‑Lista, David M.; Benavides‑García, Rosa
The construction materials of the Santalla de Bóveda Monument, one of the most studied buildings in Galicia (Spain), are analysed to date the mortars and bricks of walls and vaults by combining three dating techniques: optically stimulated luminescence, radiocarbon and thermoluminescence. Petrological characterisation of the mortars themselves is carried out. Until now, the paintings on the vault have been interpreted as Roman, early Christian or Pre-Romanesque, depending on the interpretative framework used by the researcher who studied them. There is also no consensus on their functionality. A total of 21 samples were collected, and 39 datings were made. The results are conclusive: the original building dates from the second half of the fourth century AD, the paintings date from the beginning of the seventh century or the upper floor from the tenth to twelfth centuries. These results make it necessary to review the history of Galician architecture between Late Antiquity and the Early Medieval Ages.
Le souvenir d'une certaine image. Pour Maria do Rosário Girão dos Santos
( 2023 ) Álvares, Cristina; Cabral, Maria de Jesus; Araújo, Sílvia; Varela, Conceição
Publié à l’initiative conjointe de l’APEF (Association Portugaise d’Études Françaises) et du CEHUM (Centre d’Études Humanistiques de l’Université du Minho), ce Souvenir d’une certaine image se veut avant tout un hommage rendu à Maria do Rosário Girão dos Santos par la communauté académique portugaise. Si son titre renvoie à Proust, un des auteurs de prédilection de notre collègue, le livre rassemble vingt-deux contributions – essais, témoignages et créations artistiques, s’offrant en miroir d’une activité de quatre décennies, continument poursuivie, partagée, passionnée dans la recherche et l’enseignement des études françaises et comparées.
Motion-Induced Bias in UWB Asynchronous TWR: Modeling, Analysis, and Implications
( 2026 ) Ferrero-Guillen, Ruben; Diez-Gonzalez, Javier; Martinez-Gutierrez, Alberto; Moreira, Adriano
Motion-induced uncertainties fundamentally limit the performance of asynchronous two-way ranging (TWR) localization systems, yet existing literature lacks a unified definition and characterization of these uncertainties for TWR methods. This work introduces a comprehensive characterization of motion-induced errors in TWR, establishing explicit analytical relationships between target velocity, message timing asymmetries, and the resulting ranging error. Using this formulation, four widely adopted TWR methods, single-sided TWR (SS-TWR) and symmetric double-sided TWR (SDS-TWR), each evaluated under sequential and parallel reply schemes, are assessed and compared within an optimized deployment framework derived from the spatial Cramér–Rao bound. The analysis reveals that sequential methods, commonly implemented in commercial ultra-wideband devices, offer the best performance under static conditions but degrade rapidly with motion due to accumulated timing asymmetries. In contrast, parallel configurations remain largely unaffected by velocity but are constrained by longer cumulative reply times in larger networks. Furthermore, SDS-TWR is found to be consistently more sensitive to motion than SS-TWR despite its superior correction of clock drift. The proposed framework provides the first systematic basis for quantifying motion effects in asynchronous TWR and offers practical guidelines for selecting and deploying ranging strategies in dynamic environments.