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E18 Guia temàtica revoltó prefabricat de morter de ciment
No full textDefinició, història, procediment de construcció i més informació sobre el revoltó de morter de ciment, material de construcció de la família dels prefabricats i aglomerats.2024/202
Performance evaluation of unsupervised learning application for Warren Truss Bridge anomaly detection using MLP autoencoder
No full textEnllaç a la versió publicada del capítol: https://link.springer.com/chapter/10.1007/978-3-031-96110-6_83Accurate detection of structural anomalies in bridges is crucial due to the variety of deteriorations that can compromise their safety. Traditional visual inspection methods are subjective and can miss incipient damage. This study proposes a methodology to evaluate the performance of a model based on unsupervised learning for bridge anomaly detection. Real acceleration data from a Warren truss-type steel bridge are used, which are pre-processed through standardization (mean zero and standard deviation one) and normalization (scaling the data between -1 and 1) and are divided into sequences of 5 seconds with a 200 Hz sampling rate to adequately capture temporal variations. An MLP Autoencoder with multiple hidden layers is implemented, using cross validation (KFold), Adam optimizer and mean square error (MSE) loss for training. The performance evaluation includes visualizations with PCA and UMAP, clustering with K-means, and analysis of reconstruction errors, calculating metrics such as precision, recall and F1-score, and presenting the confusion matrix. The results showed validation errors between 0.029 and 0.047, indicating moderate consistency of the model. Principal component analysis and UMAP revealed clear structures in the data, while K-Means clustering identified five distinct clusters. The model achieved an overall accuracy of 62.50%, with 76% for the majority class. This methodology provides a basis for the automated characterization of structural vibration patterns, contributing to the development of more sensitive and efficient monitoring systems for the early detection of bridge anomalies.Additionally, our gratitude extends to the Research Department of the Peruvian University of Applied Sciences for the support provided to carry out this research work through the UPC-EXPOST-2024-2 incentive.Peer ReviewedPostprint (author's final draft
Enhancing osseointegration: A proteomic evaluation and in vitro study of sol-gel surfaces doped with quercetin
No full textOne of the main challenges in dental implantology is the success of osseointegration, the process by which a solid union is produced between a dental implant and the bone. In this context, sol-gel technology is beginning to be used to obtain biocompatible surfaces that interact favorably with the environment. By incorporating quercetin (QCT), a flavonoid with anti inflammatory properties to this sol-gel technology, this study aims to make a comparison between these sol-gel surfaces doped with quercetin (QCT sol-gel) and Ti surfaces, through a proteomic evaluation and in vitro HOb adhesion studies through confocal microscopy, observing a decrease of proteins related to the activation of the immune response and coagulation for the QCT sol-gel surfaces. In addition, an increase in the cellular area of HOb adhered to the QCT sol-gel surfaces was also observed.Uno de los principales retos en implantología dental, es el éxito de la osteointegración, proceso por el cual se produce una unión sólida entre un implante dental y el hueso. En este contexto, la tecnología sol-gel se está comenzando a emplear con la finalidad de obtener superficies biocompatibles que interactúen favorablemente con el entorno. Mediante la incorporación de quercetina (QCT), un flavonoide con propiedades antinflamatorias a esta tecnología sol-gel, este estudio pretende realizar una comparativa entre estas superficies de sol-gel dopadas con quercetina (QCT sol-gel) y superficies de Ti, mediante evaluación proteómica y estudios in vitro de adhesión de HOb a través de microscopía confocal, observándose una disminución de proteínas relacionadas con la activación de la respuesta inmune y la coagulación para las superficies QCT sol-gel. Además de un aumento en el área celular de los HOb adheridos a las superficies QCT sol-gel.Peer ReviewedAward-winningPremio Congreso SIBB 202
Variacions de la relació CA/C en funció de l'edat
No full textIntroducció: El valor de la CA/C informa de la relació entre el sistema de vergència i el sistema acomodatiu. L’objectiu de l’estudi és observar les variacions de la relació CA/C en funció de l’edat dels participants.
Metodologia: Es va fer una cerca de participants entre 10 i 60 anys, amb absència d’estrabisme i ambliopia, agudesa visual monocular de unitat (20/20) i estereòpsia <70 sec arc. Es va mesurar la distància interpupil·lar, punt proper de convergència (PPC) i amplitud acomodativa (AA) i la relació CA/C gradient amb el mètode de Difference of Gaussians i la resposta acomodativa amb un prisma de 10∆ de base temporal i sense.
Resultats: Un total de 32 participants es van incloure en l’estudi, mitjana i desviació estàndard (±) de 27.2 ± 16.61 anys. De la mostra completa el valor de CA/C obtingut va ser de 0.03 ± 0.01 D/Δ. La comparació entre grups va mostrar diferències significatives en l’edat, p<0.01. De la mostra completa hi va haver una correlació estadísticament significativa entre l'edat i el valor CA/C, p=0.024. La regressió lineal per la relació CA/C amb l’edat va ser de y= 0.03 -0.0002x, i per l’amplitud acomodativa de 14.8 -0.18x.
Conclusions: La relació CA/C disminueix lleugerament amb l’edat, fet que confirma una separació fisiològica progressiva entre l’acomodació i la vergència. L’amplitud acomodativa es correlaciona fortament amb l’edat i segueix una regressió coherent amb la fórmula de Hofstetter, la qual cosa reforça la validesa dels resultats.Introducción: El valor de la CA/C informa sobre la relación entre el sistema de vergencia y el sistema acomodativo. El objetivo del estudio es observar las variaciones de la relación CA/C en función de la edad de los participantes.
Metodología: Se realizó una búsqueda de participantes entre 10 y 60 años, con ausencia de estrabismo y ambliopía, agudeza visual monocular de unidad (20/20) y estereopsis <70 segundos de arco. Se midieron la distancia interpupilar, punto próximo de convergencia (PPC) y amplitud acomodativa (AA), así como la relación CA/C en gradiente mediante el método de Diferencia de Gauss y la respuesta acomodativa con un prisma de 10∆ de base temporal y sin él.
Resultados: Se incluyeron un total de 32 participantes en el estudio, con una media y desviación estándar (±) de 27.2 ± 16.61 años. En la muestra completa, el valor de CA/C obtenido fue de 0.03 ± 0.01 D/Δ. La comparación entre grupos mostró diferencias significativas en la edad, p<0.01. En la muestra completa hubo una correlación estadísticamente significativa entre la edad y el valor CA/C, p=0.024. La regresión lineal para la relación CA/C con la edad fue de y = 0.03 - 0.0002x, y para la amplitud acomodativa de 14.8 - 0.18x.
Conclusiones: La relación CA/C disminuye ligeramente con la edad, lo que confirma una separación fisiológica progresiva entre la acomodación y la vergencia. La amplitud acomodativa se correlaciona fuertemente con la edad y sigue una regresión coherente con la fórmula de Hofstetter, lo cual refuerza la validez de los resultados.Introduction: The value of the CA/C informs about the relationship between the vergence system and the accommodative system. The aim of the study is to observe the variations of the CA/C ratio depending on the age of the participants.
Methodology: Participants aged between 10 and 60 years were recruited, with no history of strabismus or amblyopia, monocular visual acuity of 20/20, and stereopsis <70 arc seconds. Interpupillary distance, near point of convergence (NPC), accommodative amplitude (AA), and the gradient CA/C ratio were measured using the Difference of Gaussians method, as well as the accommodative response with and without a 10∆ base-out prism.
Results: A total of 32 participants were included in the study, with a mean age ± standard deviation (SD) of 27.2 ± 16.61 years. For the complete sample, the CA/C ratio obtained was 0.03 ± 0.01 D/Δ. Comparison between age groups showed significant differences (p<0.01). In the full sample, there was a statistically significant correlation between age and the CA/C value (p=0.024). The linear regression for the CA/C ratio with age was y = 0.03 - 0.0002x, and for accommodative amplitude, it was y = 14.8 - 0.18x.
Conclusions: The CA/C ratio slightly decreases with age, confirming a progressive physiological dissociation between accommodation and vergence. Accommodative amplitude strongly correlates with age and follows a regression consistent with Hofstetter’s formula, supporting the validity of the results
Decoupling elasticity, anelasticity, and plasticity in static and dynamic stress relaxation of metallic glasses
No full textThis version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Nature’s AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: http://dx.doi.org/10.1007/s11431-025-2970-4The stretched exponent Kohlrausch-Williams-Watts (KWW) equation, which is to some extent equivalent to the generalized Maxwell viscoelastic model, is widely employed for analyzing relaxation dynamics and nonelastic deformation of amorphous solids. However, it cannot reveal the underlying physical mechanisms of anelasticity. In this study, based on the potential atomic mechanisms of amorphous solids within a strain field and the traditional viscoelastic model, we introduced a physical-mechanical model involving hierarchically constrained atomic motion around defect sites. This model deduces that fast atoms move first, subsequently facilitating more complex atomic rearrangements under thermomechanical loading. These atom movement mechanisms are involved in the evolution of deformation units, such as shear transformation zones (STZs). Initially, anelasticity is associated with isolated STZs because of back stress arising from the matrix. Subsequently, the percolation of STZ by the motion of atoms owing to STZ interactions leads to irreversible deformation. The model was validated by describing the elastic, anelastic, and plastic components of stress relaxation in a La60Ni15Al25 metallic glass. Furthermore, as STZs are connected to a and ß relaxation processes, the model can be used for parameter description and component analysis of dynamic stress relaxation. The current study supplements the traditional flow defect model, providing insights into the deformation mechanisms of metallic glasses from the perspective of viscoelastic mechanics and their correlation with dynamic relaxation processes.This work is supported by the NSFC (Grant Nos. 12472069, 52271153 and 12072344); the Natural Science Basic Research Plan for Distinguished Young Scholars in Shaanxi Province (Grant No. 2021JC-12); the Natural Science Foundation of Shaanxi Province (Grant No. 2025GH-YBXM046); the Youth Innovation Promotion Association of the Chinese Academy of Sciences; Research Grant Council (RGC); the Hong Kong government through the General Research Fund (GRF) with the grant numbers CityU11200719 and CityU11213118; PID2023-146623NB-I00 and Maria de Maeztu Units of Excellence Programme CEX2023-001300-M funded by MICIU/AEI/10.13039/501100011033; 2021-SGR-00343 funded by Generalitat de
Catalunya/AGAUR.Peer ReviewedPostprint (author's final draft
Operation of large-scale irrigation systems considering storage services
No full textThe accelerating global energy transition, driven by the growth of renewable energy tech- nologies, has increased the demand on the flexibility and reliability of power systems. In parallel, the integration of variable renewable sources has introduced operational uncertainty, requiring innovative solutions to ensure grid stability. Among these, energy storage systems (ESS) are emerging as vital components for enabling resilient and efficient energy networks. However, the potential of repurposing existing infrastructure, such as irrigation systems, as storage platforms remain largely untapped. This thesis investigates the feasibility of using large-scale irrigation infrastructure as a novel energy storage solution, particularly in combination with intermittent sources like photovoltaic (PV) systems. Conducted within the framework of a European project, the research focuses on modeling hybrid water-energy systems and exploring real-time opera- tional dynamics, control strategies, and optimization methods. A representative system model is developed to evaluate system flexibility and water delivery performance under fluctuating power conditions. The analysis begins with an open-loop (uncontrolled) simulation to assess the system’s natural response to step changes in electrical power. Subsequently, a closed-loop controller is implemented and tested across three operating scenarios to examine its impact on system stability, responsiveness, and tracking accuracy. The results highlight the importance of control in enhancing performance and reliability in integrated irrigation-energy systems. This work contributes to bridging the gap between energy storage integration and water infrastructure management, offering practical insights into the design and operation of resilient, low-carbon energy systems