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ÀLGEBRA I GEOMETRIA (Examen final 1r quadrimestre)
No full textProblemesResolved2025/20261r quadrimestr
Análisis de las zonas de acumulación y orígenes de la basura marina flotante en la costa de Barcelona
No full textLas concentraciones de residuos plásticos en las aguas costeras de Barcelona se encuentran entre las más altas del mar Mediterráneo, comparables a las observadas en los giros subtropicales. Mediante análisis de datos de muestreo de ciencia ciudadana durante 2020 y 2021 y técnicas modelado numérico cuantificamos las zonas de acumulación y aportes de basuras marinas en el litoral de Barcelona. Se observa que las principales fuentes de aportes de basura marina provienen de los ríos y sistemas de descarga directa afectando fundamentalmente a las playas urbanas. Además, se ha detectado un aporte importante de basura marina externa de fuera del dominio de Barcelona. Esta situación resulta en grandes concentraciones de partículas en las playas urbanas con valores medios de 1,8 × 109 elementos por km² y⁻¹. Estos hallazgos destacan la zona costera de Barcelona como un importante emisor y receptor de residuos plásticos debido a la conectividad hidrodinámica regional y al transporte. Los altos niveles de contaminación por plásticos ponen de relieve la urgente necesidad de reducir los residuos aguas arriba y de implementar medidas de mitigación específicas para evitar que la basura llegue al ma
Descripció arquitectònica dels elements construïts dins la balma i en el territori
No full text11 - Ciutats i Comunitats Sostenibles11.4 - Redoblar els esforços per a protegir i salvaguardar el patrimoni cultural i natural del mónPostprint (published version
Rango
No full textVídeos docents de l'assignatura Representació Arquitectònica IV, impartida per Isidro Navarro, PDI de l'ETSABVídeos docentes de la asignatura Representación Arquitectónica IV, impartida por Isidro Navarro, PDI de la ETSA
Membrane effects in reinforced concrete: From experimental evidence to numerical and analytical modelling
No full textThe development of membrane effects in reinforced concrete structures allows for significant enhancements in the resistance provided that lateral movements of a structure or sub-assemblage are restricted. First, the restrained dilation of flexural cracking allows developing axial compressive forces, which increase the resistance with respect to an unconfined response, called Compressive Membrane Action (CMA) or Arching Action when referring to linear members. CMA is significant for low levels of displacements and its effect is considered in some design codes (e.g. punching resistance in EN1992–1–1:2023). For higher levels of displacement, the member elongates and the compressive forces reduce, becoming eventually in tension and activating the so-called Tensile Membrane Action (TMA). TMA has traditionally been widely considered for robustness considerations (response after accidental actions such as column removal). In this paper, a consistent treatment of CMA and TMA on reinforced concrete sub-assemblages of linear members is presented. First, a database of 56 tests is compiled, filtered and digitalized in terms of the load-displacement curve (covering a wide range of heights (90–660 mm), reinforcement ratios (0.31–1.3 %) and slenderness ratios (4¿ 27)). By analysis of the test results and interpretation using refined finite element simulations, the phenomena underlying the activation of CMA and TMA are investigated and quantified. On this basis, a general approach grounded on limit analysis is presented, both for CMA and TMA, and providing sound and consistent agreement to the test results. This approach enables simple analytical expressions for design, covering different ranges of displacement and thus providing a consistent transition from CMA to TMA. Its predictions show in addition low scatter when compared to test results, smaller than several other approaches currently available in the literature.Peer ReviewedPostprint (published version
Intra-rater reliability and agreement of a portable bioelectrical impedance analysis device for body composition assessment
No full textThis study aimed to analyze the intra-rater reliability of a new bioimpedance device, the Biody XpertZM III (BX3), and to assess its level of agreement when compared with some of the widely used body composition analyzers in clinical and healthcare settings. Its main novelty is that, in addition to the classic hand-foot protocol from a lying position (BX3-S), it proposes a new self-measurement system from a sitting position by placing its tactile electrodes in the Achilles tendon area (BX3-T). Thirty-three young active men participated in the study (22.5 ± 2.9 years, 74.9 ± 8.1 kg, 178.0 ± 6.4 cm, and 23.8 ± 2.5 kg/m2 BMI). An intra-rater reliability analysis (ICC, CV, SEM, MD, SRD) was performed for both BX3-S and BX3-T. Agreement was assessed against BIA Akern 101ASE for raw bioimpedance variables (R, Xc, Z, PhA), Inbody720 for body water content (TBW, ICW, ECW) and the GE Lunar DXA for body composition (BF, LBM, FFM). Results report ICC values ranging between 0.81 and 1.0 for BX3-S and BX3-T. CV values are below or around 10 %, except for body fat (BX3-S: 31.7 % and BX3-T: 28.0 %). There are no significant differences between BX3 (both methods) and the variables measured by DXA (p > 0.05). On the contrary, the largest differences (p < 0.001) are in Xc (BX3-T), PhA, TBW, ICW (BX3-S and BX3-T). All correlations are highly significant in both methods when compared with all the variables analysed (p < 0.001). These findings suggest that the Body XpertZM III is reliable for measuring bioimpedance and demonstrates a strong level of agreement with widely used bioimpedance devices in clinical settings for physically active young men, with advantages in portability and self-measurement capabilities. However, Xc and PhA measurements are not entirely consistent, so further research is needed in this area.All costs associated with the laboratory and its technical material were covered by the National Institute of Physical Education of Catalonia (INEFC), a public center owned by the Catalan government and attached to the University of Barcelona. Regarding the authors, A.C-P. was a pre-doctoral researcher supported by a FPU pre-doctoral contract from the Spanish Ministry of Education, Culture and Sport [FPU20/00998]. J.E-L. was a predoctoral researcher supported by a grant within the field of physical education, physical activity, and sports and its applied sciences given to the INEFC [PINEFC 00012].Postprint (author's final draft
Pla sencer de la regidora Isabel Sánchez Pulido durant la seva intervenció a l'acte de lliurament del Premi Rosa Argelaguet i Isanta a la BCUM
No full textFerran Marqués: “El metge pot fer un diagnòstic més acurat i definir el tractament més correcte”
No full textEls vuit hospitals de l’ICS han optimitzat el diagnòstic del càncer de mama gràcies a uns algorismes d’intel·ligència artificial creats pel Grup de Processament d'Imatge i Vídeo de la UPC, en el marc del projecte DigiPatICS. Les mostres de teixit potencialment afectades es digitalitzen i els algorismes les analitzen automàticament, fet que permet diagnosticar abans i millor la malaltia. A més, els resultats es comparteixen a tots els hospitals i el personal mèdic pot supervisar-los conjuntament, creant així la xarxa d’anatomia patològica digital més gran d'Europa. El projecte ha estat guardonat amb el 15è Premi UPC de Valorització de la Recerca, lliurat el 19 de novembre i convocat pel Consell Social amb el suport de Fractus i del Fractus-UPC Deep Tech Hub
Optimizing the recovery of rare earth elements from acid mine water: a sustainable approach using selective precipitation
No full textThis study focuses on the recovery of rare earth elements (REEs) from acid mine water (AMW) through a two-step selective process, which consists of a selective extraction with ion exchange followed by a precipitation stage using oxalic acid. Optimization of the effective REE recovery from sulphuric ion-exchange concentrates results in sustainable AMW management, providing a secondary resource for critical metals towards green transition. Experimental results indicate that (1) the use of oxalic acid facilitates the formation of REE-oxalate crystals, yielding recovery efficiencies in light rare earth elements (LREEs) much higher than for heavy rare earth elements (HREEs) at specific excess doses, and that (2) LREEs act as precursors for HREE precipitation. Moreover, REE-oxalate crystallization depends on the oxalic acid dose, pH, and precipitation time (PT). The longer the PT, the larger the crystals, which are economically advantageous. The study highlights that AMW is a potential secondary source for the REE recovery, which contributes to sustainable mining practices and provides confidence for further optimization of REE recovery processes.This research was supported by EIT-Raw Material through the project “Metal Influenced Acid Water as a source of valuable and critical raw materials” (REEcovery, PN-21033) and the Spanish Research Agency (AEI) through the project Upcycling project (Development of upcycling approaches in the agri-food and process industries to promote on-site and sustainable chemicals production; PID2023-147160OB-C21) and the MET4LIBS project (Integration of waste processing technologies to ensure a safe, circular and sustainable battery value chain by promoting urban and industrial mining (MET4LIBS; TED2021-131583B-I00). This work was carried out within the framework of the Multiscale Center of Excellence, funded by the María de Maeztu Program for Units of Excellence (CEX2023-001300-M), supported by MCIN/AEI/Ministerio de Universidades, Spain and the Catalan Government through the R2EM group (2021-SGR-GRC-00596). Support for the research of J.L. Cortina was also received through the “ICREA Academia” recognition for excellence in research funded by the Generalitat de Catalunya. J. Cama acknowledges funding from the Catalan Government through the 2021 SGR 00308 project. We acknowledge the Editor Yang Liu and the anonymous reviewers for their constructive comments that increased the quality of the paper.Peer ReviewedPostprint (published version