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Ítem Detailed study of tube hot rolling process by means of FEM(Association of American Publishers, 2023) García Gil, Eduardo ; Llamazares Duran, Gorka; Conde Fernández, Aintzane; Murillo Marrodán, Alberto; Barco Atutxa, JonIn this paper seamless tubes hot manufacturing calibration rolling is studied by means of a finite element model, to improve product quality and process performance. Based on real data provided by an industrial partner, Tubos Reunidos Group, a finite element model of the process has been created and validated for the thermo-mechanical analysis of the process. The model has been used for the study of the wall thickness evolution and peripherical distribution during process, the eccentricity and the polygonization effects. Results show that the tube velocity in the process is one of the factors affecting wall thickness eccentricity, due to mass flow conservation. Regarding polygonization and eccentricity effect it has been found that both effects increase in the rolling stands with higher reduction ratio, and are corrected afterwards. These effects are mainly due to the ovality of the rolls. However, the effect the different sliding velocity along roll perimeter has implications in the local deformation of the material in contact with the roll, causing local compressive stress areas in addition to the predominant tension areas.Ítem La imagen de Europa en el semanario vasco Euzko Deya(PILAR (Presse, Imprimés, Lecture dans l’Aire Romane), 2023) Arrieta Alberdi, LeyreÍtem University graduates enrolled in higher VET in Spain: an upskilling or reskilling choice?(Universidad Politecnica de Valencia., 2023) Diego Rodríguez, Iván; Gamboa Navarro, Juan PabloPost-Baccalaureate reverse transfer students (PRTSs) are students that enroll at a VET institution after completion of at least a bachelor's degree. This paper is an exploratory, descriptive and correlational study of Higher VET graduates with a previous university qualification in Spain. The purpose of this study is to contribute to the knowledge of PRTSs in Spain by identifying if it is an upskilling or reskilling choice. The study uses data from the ETEFIL-19 survey to examine the demographics, previous degrees, program of enrollment, and prevalence of university graduates who get VET degrees. The results suggest that the transition of university graduates in Spain into Higher VET is best interpreted as an upskilling strategy due to a significant correlation between the original university field and the VET professional field of destination. A summary discussion of the results along with implications and recommendations for the practice, policy and further research are included.Ítem Travel behavior shifts under extreme system-level disruptions(Elsevier B.V., 2023) Gasparinatou, Christina; Mantouka, Eleni; Vlahogianni, Eleni I.; Masegosa Arredondo, Antonio David ; Serrano, LeireThis paper attempts to identify and critically discuss how travel behaviour may be affected by any extreme system-level conditions of the transportation system in the cities. These disruptions refer to non-recurrent events and indicatively include hazardous events, and perturbations of the road network. To this end, the international literature on the changes in travel behaviour in the case where system-level disruption occur is collected and analysed. The analysis is conducted on the basis of the three pillars of travel behaviour, namely travel mode, route and departure time choices. The results show that most people tend to postpone their trip when extreme weather conditions occur, whereas in case of a public transportation disruption travellers are keen on altering their route choice. Finally, a clear mode shift towards cars has been observed due to the outbreak of COVID-19 pandemic.Ítem Study of forming defects and failure occurrence in the radial-axial rolling of super duplex stainless steel rings(Association of American Publishers, 2023) Murillo Marrodán, Alberto ; García Gil, Eduardo ; Fernández de Gamboa Andrío, Unai; Conde Fernández, Aintzane; Lozares Abasolo, JokinWelding neck flanges are commonly manufactured by radial-axial ring rolling (RARR). The service conditions of these elements are very demanding (mechanical loads and corrosive environments). For this reason, materials such as super duplex stainless steel (SDSS) are used, which could present workability problems under certain process conditions. In this work, a study of forming defects and failure occurrence in the RARR of SDSS flanges has been proposed. Firstly, a finite element model of the industrial RARR process was developed and validated. Then, a multivariate factorial analysis based on a virtual design of experiments was performed to identify the determinant parameters of the process. The diameter of the mandrel was identified as the most determinant parameter. An increase in diameter reduces the probability of developing underfilling defects and the development of cracks in the flange neck. The mandrel radial speed has no significant effect on the cracking of underfill defects while reducing the rotational speed of the king-roll could improve the uniformity of the deformation distribution in the flange section.Ítem Digital twin development for the sensitivity analysis of near solidus forming process(Association of American Publishers, 2023-04-19) Sajjad, Muhammad; Plata Redondo, Gorka ; Lozares Abasolo, Jokin; Mendiguren Olaeta, JosebaNear Solidus Forming (NSF) process, performed at semi-solid material state is gaining popularity due to its good physical properties, low manufacturing cost and material waste. Although the process possesses many advantages over traditional hot forging, the nature of the process itself is very complex and due to this the researcher struggles to identify the material behavior at NSF conditions. Especially the material model in this condition has not been stated clearly before and therefore it is important to develop a reliable digital twin (DT) strategy which can validate the material model efficiently. Therefore, the objective of this work is to investigate the influence of all DT parameters like billet material and dimensions, billet and dies temperature, heat transfer coefficient, emissivity, ambient temperature, and friction coefficient, in two industrial components such as H spindle and R spindle. The Taguchi Design of Experiments (DOE) approach combined with numerical simulation in FORGE NxT® is employed to develop the sensitivity analysis of the process. The impact of all parameters in the DT are evaluated in terms of die filling and forming forces, and its importance in the material model is studied. Results show that the newly developed approach proposed a novel optimum NSF-DT calibration strategy for material-model validation. Which can be used to develop an accurate model of the NSF process at the laboratory and industrial scale.Ítem IEM: a unified lifecycle orchestrator for multilingual IaC deployments(Association for Computing Machinery, Inc, 2023-04-15) Díaz de Arcaya Serrano, Josu; Osaba, Eneko ; Benguria, Gorka; Etxaniz Errazkin, Iñaki; López Lobo, Jesús ; Alonso, Juncal; Torre Bastida, Ana Isabel ; Almeida, AitorOver the last few years, DevOps methodologies have promoted a more streamlined operationalization of software components in production environments. Infrastructure as Code (IaC) technologies play a key role in the lifecycle management of applications, as they promote the delivery of the infrastructural elements alongside the application components. This way, IaC technologies aspire to minimize the problems associated with the environment by providing a repeatable and traceable process. However, there are a large variety of IaC frameworks, each of them focusing on a different phase of the operationalization lifecycle, hence the necessity to master numerous technologies. In this research, we present the IaC Execution Manager (IEM), a tool devoted to providing a unified framework for the operationalization of software components that encompasses the various stages and technologies involved in the application lifecycle. We analyze an industrial use case to improve the current approach and conclude the IEM is a suitable tool for solving the problem as it promotes automation, while reducing the learning curve associated with the required IaC technologies.Ítem Kooperatiben arteko lankidetza gizarte-erronkei aurre egiteko lanabes gisa(Universidad del País Vasco = Euskal Herriko Unibertsitatea, Servicio Editorial = Argitalpen Zerbitzua, 2024) Arrieta Idiakez, Francisco JavierÍtem GoiEner energy cooperative a social economy initiative facing the challenge of degrowth(Universidad del País Vasco = Euskal Herriko Unibertsitatea, 2024) Damborenea Iglesias, Mario; Atutxa Ordeñana, Ekhi; Mendizabal Leiñena, XabierThe current situation of climate crisis, resource depletion and growing inequalities has led to the emergence of several alternative proposals to the conventional economic model. Among them arises the proposal of degrowth, which questions the current developmentalism and proposes a reduction in the use of resources, as well as a more equitable distribution of them. To analyse its viability, it is necessary to study the existence of degrowth initiatives in practice. For this purpose, using the methodology of the ethical triangle and the characterization of degrowth based on its normative and applied principles, the case of the Basque energy cooperative GoiEner is analysed to determine whether it can be considered a fully degrowth organization. The analysis shows that, although GoiEner is not yet one, by making progress in complying with the defined principles, it has the potential to become one in the future.Ítem Elaboración de un portafolio electrónico para el desarrollo docente a través de una Unidad Didáctica Virtual(Universidad de Zaragoza, Servicio de Publicaciones, 2021) Romero Yesa, Susana; Aláez, Marian; García Olalla, Ana María; Segú Odriozola, MabelLa docencia de calidad es una preocupación fundamental en las universidades. La evaluación acreditativa del profesorado a través de las agencias de calidad responde a esa inquietud. En la Universidad de Deusto, esta acreditación se estructura en tres niveles: la acreditación de la planificación de la docencia, la acreditación de su puesta en práctica y la revisión y mejora desde un enfoque de colegialidad. En esta comunicación nos centramos en la segunda. El profesorado se debe presentar a una evaluación acreditativa mediante la preparación de un portafolio docente. La Unidad de Innovación Docente ofrece talleres en los que los coordinadores de los centros acompañan a los profesores en su elaboración. Además de esta formación presencial, el profesorado necesita contar con documentación de apoyo accesible y actualizada. Para dar respuesta a esta necesidad, se ha elaborado en la plataforma institucional tipo Moodle, mediante un proyecto de innovación docente, una Unidad Didáctica Virtual (UDV) de apoyo a la formación presencial. En ella se ha elaborado una plantilla y se han incluido recursos como presentaciones, vídeos, foros y ejemplos de las evidencias a presentar. Los resultados han sido muy satisfactorios en relación con el cumplimiento de los objetivos establecidos e indicadores de impacto.Ítem Actividades transversales entre materias de primer curso de grado y trabajo en equipo para aumentar la motivación del alumno(Universidad de Zaragoza, Servicio de Publicaciones, 2021) Fonseca Escudero, David ; Necchi, Silvia; Aláez, Marian ; Romero Yesa, Susana; Centeno Hernández, EfraimMotivar al alumno de primer curso de grado, no solo mejora su grado de satisfacción y su rendimiento, sino que puede prevenir el riesgo de abandono temprano de los estudios. En este sentido, para potenciar la motivación se antoja como estrategia importante trabajar las competencias específicas desde un abordaje transversal, menos específico y que permita al alumno vislumbrar las potencialidades de sus estudios y de sus relaciones entre iguales. El presente artículo muestra el resultado de dos actividades transversales realizadas en el primer curso del grado de Estudios en Arquitectura, donde el trabajo en equipo es esencial para su entrega. Los resultados han permitido identificar tanto fortalezas como debilidades de cada práctica gracias a su enfoque mixto (cuantitativo / cualitativo), lo que permitirá un rediseño de las actividades para el siguiente curso.Ítem Ocio y aprendizaje a lo largo de la vida: un binomio en positivo(REDINE (Red de Investigación e Innovación Educativa), 2020) Lázaro Fernández, Yolanda; Doistua Nebreda, JosebaÍtem Model-based outlier detection in district heating systems(Elsevier B.V., 2024) Garay Martínez, Roberto; Siddique, Muhammad Talha; López Garde, Juan ManuelData-driven methods are increasingly popular for building energy performance assessment. For these to be useful, it is required that good quality data is created through the filtering of outliers and imputation of missing information. In the field of energy use in buildings, there is a clear sensitivity of heat load to outdoor climate, which needs to be considered when identifying outliers and developing imputation methods. We propose to use a well-known changepoint model to define the sensitivity of the data to climate, further segmented by time of the week. Then we use the residuals of the model to identify outliers, where those observation with residuals substantially out of the normality expectations are identified as outliers. Then missing data is repaired by means of linear imputation techniques, considering the patterns for same times of the week in the dataset. As a result of the full process, we were able to identify 5% of outliers, which resulted in the improvement of model metrics in the range of 20% mean absolute error (MAE) and slightly better R2 values.Ítem Design of monitoring tool for decision making in buildings with solar energy generation(Elsevier B.V., 2024) García Quintanilla, José Ignacio; Macarulla, Ana María; Sainz Bedoya, Nekane Ione; Canivell Castillo, VerónicaThe work presented in this article is part of a project that focuses on the field of energy and sustainability and is aligned with the objectives of sustainable development, specifically goal seven, affordable and clean energy, and goal eleven, sustainable cities and communities. The photovoltaic solar installation for self-consumption at the Deusto University's residence hall been modelled using generation data, consumption data, meteorological data, and installation components. Although the actual installation features an anti-feeding system, the model allows to evaluate potential energy surpluses. To achieve this objective, it has been necessary to collect, transform, and thoroughly clean the data from the solar inverters, as well as store them for later representation. To process, visualize, and analyse data, the web application developed allows users to understand quickly and easily the patterns and trends related to energy consumption through various graphics, providing a clear and accessible visual presentation of the data that helps them make decisions to optimize energy consumption. In addition, an application has been developed that allows to assess whether or not removing the anti-feeding system and modifying the contract with the distribution company may be favourable.Ítem Optical and thermal modeling of a transparent BIPV system for dynamic performance in buildings(Elsevier B.V., 2024) Garay Martínez, Roberto; Siddique, Muhammad TalhaIn developed countries, the building sector accounts for up to 40% of the consumed energy. During the past centuries, fossil fuels have been the main energy source to heat, cool, or provide electric power to buildings, but with the increasing energy prices in the beginning of the 21st century, an increasing number of products and systems have been developed for the integration of renewable energy systems in the building sector. One of the most commonly used technologies involves the integration of photo-voltaic (PV) systems in the building fabric. Several technical solutions are available for this integration, although most common ones are related to PV integration in roofs. However, an increasing interest has been shown in semi-transparent PV systems for integration in windows and curtain-wall systems.Ítem Adaptability and efficiency in population management: a multi-population CMA-ES strategy for high-dimensional optimization(Elsevier B.V., 2024) Morales Castañeda, Bernardo; Rodríguez Esparza, Erick; Oliva, Diego; Navarro, Mario A.; Aranguren, Itzel; Casas Ordaz, Ángel; Beltran, Luis A.; Zapotecas Martínez, SaúlIn the context of evolutionary algorithms, having the ability to adapt to any search space within an optimization problem is an essential task. Appropriately adapting the population can lead to better solutions and more efficient use of function call resources. This article presents a renewed approach to population management inspired by modifying the well-known Covariance Matrix Adaptation Evolution Strategy (CMA-ES) algorithm. The proposed strategy aims to improve the algorithm's population adaptability to the search space and optimize function evaluations. Statistically evaluated experimental test outcomes demonstrate significantly better performance on high-dimensional problems in comparison to the original CMA-ES and seven other known evolutionary algorithms in the literature.Ítem On the improvement of generalization and stability of forward-only learning via neural polarization(IOS Press BV, 2024-10-16) Terres Escudero, Erik B.; Ser Lorente, Javier del; García Bringas, PabloForward-only learning algorithms have recently gained attention as alternatives to gradient backpropagation, replacing the backward step of this latter solver with an additional contrastive forward pass. Among these approaches, the so-called Forward-Forward Algorithm (FFA) has been shown to achieve competitive levels of performance in terms of generalization and complexity. Networks trained using FFA learn to contrastively maximize a layer-wise defined goodness score when presented with real data (denoted as positive samples) and to minimize it when processing synthetic data (corr. negative samples). However, this algorithm still faces weaknesses that negatively affect the model accuracy and training stability, primarily due to a gradient imbalance between positive and negative samples. To overcome this issue, in this work we propose a novel implementation of the FFA algorithm, denoted as Polar-FFA, which extends the original formulation by introducing a neural division (polarization) between positive and negative instances. Neurons in each of these groups aim to maximize their goodness when presented with their respective data type, thereby creating a symmetric gradient behavior. To empirically gauge the improved learning capabilities of our proposed Polar-FFA, we perform several systematic experiments using different activation and goodness functions over image classification datasets. Our results demonstrate that Polar-FFA outperforms FFA in terms of accuracy and convergence speed. Furthermore, its lower reliance on hyperparameters reduces the need for hyperparameter tuning to guarantee optimal generalization capabilities, thereby allowing for a broader range of neural network configurations.Ítem Reinterpretando una obra del Museo del Prado a través de la óptica del diseño y la fabricación digital(MusicoGuia, 2024) Fernández Gago, Paula; Martínez Rodríguez, RodrigoEste trabajo fusiona el pensamiento de diseño, el arte y el uso de la tecnología en la educación superior. El reto se centra en reinterpretar la obra “La extracción de la piedra de la locura” de El Bosco, actualizando su lenguaje al siglo XXI. Para ello se llevó a cabo un proyecto guiado por el pensamiento de diseño, que abarcó desde la investigación del catálogo del Museo hasta el fomento de la creatividad a través de la conceptualización de la propuesta, finalizando con la materialización de la misma haciendo uso de tecnologías de fabricación digital. Todo ello con el objetivo último de transmitir un mensaje crítico sobre las adicciones y las contradicciones de la sociedad actual.Ítem Análisis crítico de la protección del nómada digital: entre precariedad y privilegio digital(Laborum, 2024-10-20) Martínez Martínez, IreneÍtem Ajustes y desajustes en las prestaciones de seguridad social para con las personas trabajadoras a tiempo parcial(Laborum, 2024-10-20) Arrieta Idiakez, Francisco Javier
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