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Fórum Universal de las Culturas 2004. El último gran cambio urbanístico de Barcelona
No full text11 - Ciutats i Comunitats SosteniblesPostprint (published version
MECÀNICA (Examen final 1r quadrimestre)
No full textPreguntes curtes i problemesResolved2025/20261r quadrimestr
Mapping water content dynamics in SAT systems using 3D electrical tomography
No full textThe growing demand for high-quality water requires sustainable strategies to promote reuse and recycling. Managed Aquifer Recharge strategies, particularly Soil-Aquifer Treatment systems, have demonstrated effectiveness in improving water quality by reducing contaminants through biodegradation, retention, and sorption. The coexistence of solid, liquid, and gas phases in the unsaturated zone enhances adsorption, and retention of pathogens and colloids, while the availability of organic carbon and terminal electron acceptors sustains this zone as critical for biodegradation processes. During recharge, the hydration-drainage front in the unsaturated zone follows a depth-dependent pattern. However, soil heterogeneity causes water to infiltrate through preferential pathways, gradually hydrating the surrounding medium. This behavior is further influenced by system management (recharge strategy, applied flow rate, and/or installation of reactive barriers), which also promotes the development of biofilms. These biofilms facilitate water retention and act as localized microreactors for contaminant biodegradation. We investigate the influence of recharge strategies (pulsed versus continuous) and the presence of a reactive barrier on the hydration-drainage front in the unsaturated zone and biofilm development in two Soil-Aquifer Treatment systems. This was achieved using cross-hole electrical resistivity tomography, combined with the assessment of biofilm formation through extracellular polymeric substances quantification in solid samples collected from the unsaturated zone during the recharge episodes. The study compares two Soil-Aquifer Treatment systems: one composed of fine sand and another incorporating a reactive barrier consisting of sand, woodchips, compost, biochar, zeolites, and clay. Two recharge episodes were analyzed: one operated under continuous flow and the other under pulsed flow, while maintaining the same average flow rate. Resistivity measurements, associated with the properties of the porous medium and the fluids circulating through it, were acquired under the initial dry conditions and throughout recharge, revealing the 3D distribution of the unsaturated zone volume during hydration (at the start of recharge) and drainage (when recharge ceased). Over time, these measurements also indicated the potential formation of biofilms in the Soil-Aquifer Treatment system. Measurements at the beginning and end of each recharge episode capture the 3D evolution of water content. Results showed that water infiltration occurred through preferential pathways or fingers, creating significant heterogeneity in water content in both Soil-Aquifer Treatment systems. The reactive barrier enhanced water retention during dry periods, supporting biofilms development. Furthermore, the pulsed recharge strategy promoted biofilm growth more effectively than the continuous recharge strategy. These findings provide insight into optimizing recharge strategies and media composition to manage system dynamics and, consequently, enhance contaminant removal in Soil-Aquifer Treatment systems.Acknowledgements. We would like to express our gratitude to the Consorci d’Aigües de la Costa Brava Girona (CACBGi) for their support at the WWTP. Financial support. This research has been supported by the Ministerio de Ciencia e Innovación (grant nos. TED2021-131188B-C31, PCI2019-103603, PCI2019-103425, RYC2023-045649-I, and LIFE REMAR LIFE20 ENV/ES/000284), the Agència de Gestió d’Ajuts Universitaris i de Recerca (grant no. AGAUR-SGR00609), the Agencia Estatal de Investigación (grant nos. RYC2023-045649- I and LIFE REMAR LIFE20 ENV/ES/000284), and the European Commission, NextGenerationEU (grant no. TED2021-131188BC31). The article processing charges for this open-access publication were covered by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI). Review statement. This paper was edited by Xavier Sanchez-Vila and reviewed by Alex Furman and one anonymous referee.Peer ReviewedPostprint (published version
Study of the influence of finite element shape functions on the numerical performance of pantograph–catenary interaction simulations
No full textThis thesis investigates the influence of the order of the shape functions adopted for an Euler–Bernoulli beam element and of refinement strategies on the numerical prediction of the contact force exchanged in the pantograph–catenary system. In particular, baseline configurations are compared with meshes featuring an increased number of elements (element refinement) and with formulations employing enriched elements (p-refinement), in order to quantify their impact on both accuracy and computational cost. The model is developed within a finite-element framework, using implicit Newmark time in- tegration and a penalty-based contact formulation, and it is validated against the reference solution by Collina and Bruni. Building on this basis, an adaptive strategy is proposed, based on the localized enrichment of elements within a moving window centred on the contact region, with the aim of reducing the computational time while maintaining an accuracy level comparable to that of a fixed mesh. The results indicate that a narrow window (nf = 2) with third-order local enrichment provides a particularly favourable trade-off for repeated simulations, whereas wider win- dows (e.g. nf = 10) may be preferable when a more global representation of the system response is required, capable of capturing wave propagation even in regions far from the contact zone.Incomin
RV.S6.DR.V1 Contenido
No full textVVídeos docents de l'assignatura Representació Arquitectònica II (REVIT) impartida per Isidro Navarro, PDI de l'ETSABVídeos docents de l'assignatura Representació Arquitectònica II (REVIT) impartida per Isidro Navarro, PDI de l'ETSA
Dirección de operaciones. Producto, proceso y sistema productivo. TR DO 2025 26 MUEO Sistema productivo
No full textTema 1: Producto, proceso y sistema productivo
(1) Sistema Productivo. (2) Producción, empresa y mercado. (3) Clasificación de los sistemas productivos. (4) Decisiones en los sistemas productivos. (5) Los 3 niveles de decisión en DO. (6) Logística. (7) Sistema logístico-productivo. (8) Sistemas de gestión.2025/20262n quadrimestr
RV.S1.C1.V7 Creación de un Plano
No full textVídeos docents de l'assignatura Representació Arquitectònica II (REVIT) impartida per Isidro Navarro, PDI de l'ETSA
Blink rate self-regulation, tear volume and ocular symptoms in expert and naïve action video game players
No full textClinical relevance: Alterations in blink rate and dynamics are common during visually demanding tasks such as video gaming or digital device use, leading to tear film instability and ocular and visual symptoms. Background: Sustained visual attention during gaming may reduce blink frequency and alter tear production, increasing ocular surface symptoms. The aim of this study was to determine whether experienced action video game (AVG) players exhibited adaptations in blink rate and tear volume compared with non-video game (NVG) players, and to explore the relationship between these adaptations and ocular symptoms. Methods: Thirty participants (17 AVG and 13 NVG) were enrolled. All participants played Call of Duty: Modern Warfare® (Zombies mode) for 25 minutes under controlled conditions. Blink rate was recorded at baseline and during dynamic and non-dynamic scenes using the Pupil Core eye tracker. Tear volume was assessed with the Schirmer test before and after gameplay. Dry eye symptoms were evaluated using the SANDE questionnaire at baseline and the IOSS questionnaire every five minutes during gameplay. Results: No significant group differences were observed at baseline in blink rate, tear volume, or SANDE scores (all p > 0.05). During gameplay, AVG players exhibited significantly lower blink rates than NVG players in both dynamic (5.94 ± 2.61 vs. 7.88 ± 2.40 blinks/min, p = 0.045) and non-dynamic scenes (10.44 ±3.34 vs. 13.73 ± 3.82 blinks/min, p = 0.018). Schirmer test values did not differ significantly pre – post session (p > 0.05). IOSS scores increased during gameplay in both groups (p < 0.0001), appearing earlier in NVG players. Conclusion: Expert AVG players demonstrate altered blink behaviour compared with NVG players, possibly reflecting adaptations that minimise visual information loss. These adaptations may influence ocular surface health during prolonged visual tasks. Further research is warranted to clarify the mechanisms underlying these changes.M.A. and M.V. would like to acknowledge the support provided by the project PID2023-146101OB-I00 financed by MCIU/AEI/10.13039/501100011033/FEDER, UE.Peer ReviewedPostprint (author's final draft
Subministrament d'aigua a un municipi
No full textAquest Treball de Fi de Grau té com a objectiu l’estudi i el disseny d’una xarxa de subministrament d’aigua regenerada procedent del tractament terciari avançat de l’Estació Regeneradora d’Aigua (ERA) del Prat de Llobregat, destinada a l’abastament d’indústries dels polígons de la Zona Franca i del Polígon Pratenc, així com d’habitatges i serveis del sector de la Marina del Prat Vermell. El projecte s’emmarca en un context de gestió eficient dels recursos hídrics i de foment de la reutilització de l’aigua com a eina clau per a la sostenibilitat ambiental i econòmica. La metodologia emprada es fonamenta en l’estudi comparatiu de diverses alternatives de traçat de la canonada principal entre l’ERA del Prat de Llobregat i el dipòsit de regulació de Montjuïc, considerant tant la construcció de noves infraestructures com el reaprofitament de canonades existents. L’avaluació s’ha realitzat mitjançant una anàlisi multicriteri que integra criteris econòmics, tècnics, operatius, ambientals i socioeconòmics, amb ponderacions específiques per a cadascun d’ells. A partir dels resultats obtinguts, s’ha seleccionat l’alternativa que ofereix el millor equilibri entre cost, viabilitat constructiva i fiabilitat operativa, així com una adequada capacitat d’adaptació a futures ampliacions de la demanda. Un cop definida l’alternativa òptima de traçat, el treball es completa amb el disseny hidràulic dels ramals de distribució que permeten l’abastament d’aigua regenerada a les indústries i als diferents àmbits de demanda. Aquest disseny inclou el dimensionament de les canonades, la verificació de pressions, cabals i velocitats, així com la simulació del funcionament del sistema mitjançant EPANET, assegurant el compliment dels criteris de qualitat de servei i un funcionament robust de la xarxa en els diferents escenaris de consum
Predimensionament de turbomàquines amb Blade Modeler d’ANSYS CFX
No full textLa present memòria té com a principal objectiu el predimensionament de rodets centrífugs radials mitjançant el programa Ansys. A partir de paràmetres bàsics de rodets reals, es generen diferents geometries amb la finalitat d’analitzar si el seu comportament geomètric i operatiu és coherent amb el dels rodets de referència. Paral·lelament, el treball també té com a objectiu establir una metodologia de disseny de turbomàquines aplicable a futures assignatures del MUEI (Màster Universitari en Enginyeria Industrial). La metodologia es basa en la generació d’una geometria 1D amb l’eina Vista CPD, la posterior transformació en un model tridimensional amb BladeGen i, finalment, l’avaluació del comportament hidràulic mitjançant simulacions fluidodinàmiques amb CFX. Els resultats obtinguts evidencien que existeixen diverses configuracions geomètriques capaces d’assolir unes mateixes condicions d’operació. Tot i presentar certes similituds, aquestes geometries no poden considerar-se equivalents. L’estudi comparatiu mostra que l’increment del nombre de paràmetres definits en el predimensionament, comporta una reducció de la desviació geomètrica entre les mostres analitzades. Finalment, les simulacions de dinàmica de fluids han permès avaluar el comportament hidràulic de les geometries generades, posant de manifest la presència de certes desviacions atribuïbles a les limitacions dels models emprats. En aquest sentit, es pot afirmar que les eines proporcionades per Ansys constitueixen un entorn versàtil i útil per al disseny preliminar de turbomàquines, sempre que els resultats obtinguts siguin posteriorment validats mitjançant anàlisis més detallades