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El projecte descriu una solució a un pas superior per a ferrocarril a una nova línia programada al Pla Territorial Parcial de Tarragona. Aquesta obra ha de superar un obstacle de 40 metres, l'AP-7, assolits amb una secció artesa prefabricada.

The use of 3D concrete printing (3DCP) opens a wide range of new and revolutionary possibilities in the construction industry. However, the development of materials and the manufacturing of structural elements face several challenges that need to be addressed to produce safe and reliable 3DCP structures. Accordingly, and given the layer-to-layer based 3DCP manufacturing method, further research is required to identify the properties of the internal structure of the material and its influence on the structural performance. This study aims at analysing the performance of a 3DCP material through an experimental programme involving the characterisation of a 3DCP material and the analysis of the behaviour under flexure of a 3DCP wall manufactured using the Contour Crafting procedure. For this, concrete beams were printed to extract cores and determine the mechanical properties of concrete, while analysing the anisotropy of the material in different directions. Additionally, a wall with dimensions 2.70x1.20x0.30 m was produced and tested under a three-point bending configuration. The mechanical characterisation of 3DCP cores revealed an anisotropic behaviour of the material in the different testing directions due to the layer-based structure of the printing procedure. The results of the 3DCP wall tested under flexure exhibited a failure in different stages as a result of the presence of irregularities introduced by the printing manufacturing method. Consequently, both the anisotropy and the irregularities of the structural elements need to be taken into account at the design stage given its significant impact on the strength and the influence on the structural behaviour. These results provide valuable information about the behaviour of concrete printed materials and show the necessity of developing design specifications beyond those currently in use for traditional poured concrete. © Fédération Internationale du Béton – International Federation for Structural Concrete., Peer Reviewed, Postprint (published version)

OpenMP can be used in real-time applications to enhance system performance. However, predictability of OpenMP applications is still a challenge. This paper investigates heuristics for the mapping of OpenMP task graphs in underlying threads, for the development of time-predictable OpenMP programs. These approaches are based on a global scheduling queue, as well as per-thread allocation queues. The proposed method is divided into scheduling and allocation phases. In the former phase, OpenMP task-parts are discovered from OpenMP graph and placed in the scheduling queue. Afterwards, an appropriate allocation queue is selected for each task-part using four heuristic algorithms. In the latter phase, the best task-part is selected from the allocation queue to be allocated to and executed by an idle thread. Preliminary simulation results show that the new method overcomes BFS and WFS in terms of scheduling time and idle time., This work has been co-funded by the European commission through the AMPERE (H2020 grant agreement N° 745601) project., Peer Reviewed, Postprint (author's final draft)

The postcracking capacity of fiber reinforced concrete (FRC) mainly depends on the content, material, and geometry of the fibers considered. Even though the general influence of these factors on FRC behavior has been extensively addressed, the uncertainty of the FRC performance prediction along with the variability of the results still poses a challenging issue that needs to be solved to encourage the use of FRC for design and construction purposes. In this line, a database including the results of the flexural residual strength obtained from different experimental programs combined with the results of previous studies has been gathered and analyzed herein to obtain general correlations and trends providing additional information about the influence of the fibers in FRC behavior, these meant to serve for initial design stages (e.g., make decisions on the type and amount of fibers based on technical and economical requirements). The results are analyzed distinguishing between the fiber material, the fiber shape, the aspect ratio and tensile strength. The results presented herein may provide valuable information on the initial prediction of the residual strength of FRC to fully take advantage of the mechanical properties of the material., The authors from UPC wish to express their acknowledgment to the Ministry of Economy, Industry and Competitiveness of Spain for the financial support received under the scope of the projects BIA2016-78742-C2-1-R and PID2019-108978RB-C32., Peer Reviewed, Postprint (published version)

This chapter describes a software architecture for processing big-data analytics considering the complete compute continuum, from the edge to the cloud. The new generation of smart systems requires processing a vast amount of diverse information from distributed data sources. The software architecture presented in this chapter addresses two main challenges. On the one hand, a new elasticity concept enables smart systems to satisfy the performance requirements of extreme-scale analytics workloads. By extending the elasticity concept (known at cloud side) across the compute continuum in a fog computing environment, combined with the usage of advanced heterogeneous hardware architectures at the edge side, the capabilities of the extreme-scale analytics can significantly increase, integrating both responsive data-in-motion and latent data-at-rest analytics into a single solution. On the other hand, the software architecture also focuses on the fulfilment of the non-functional properties inherited from smart systems, such as real-time, energy-efficiency, communication quality and security, that are of paramount importance for many application domains such as smart cities, smart mobility and smart manufacturing., The research leading to these results has received funding from the European Union’s Horizon 2020 Programme under the ELASTIC Project (www.elastic-project.eu), grant agreement No 825473., Peer Reviewed, Postprint (published version)

Debido a la reducción de la resistencia residual del hormigón reforzado con fibras (HRF) al incrementar el tamaño de un elemento, resulta de gran interés determinar el alcance del efecto escala para el cálculo de los parámetros del modelo constitutivo. Para ello, se han realizado ensayos de flexotracción en probetas de tres dimensiones planteando el uso de la rotación de la probeta como alternativa a la abertura de fisura para establecer los valores fR1 y fR3 del modelo constitutivo. Tras comparar los resultados experimentales con una simulación por análisis inverso, se observa que la utilización de la rotación de la probeta en lugar de la abertura de fisura lleva a resultados menos influenciados por el efecto escala., Los autores agradecen el apoyo económico del Ministerio de Economía, Industria y Competitividad a través del proyecto SAES (BIA2016-78742-C2-1-R). El primer autor agradece el apoyo económico del Ministerio de Ciencia, Innovación y Universidades a través de la beca FPU., Postprint (published version)

© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., The electromagnetic compatibility of wide-bandgap (WBG) power converters can be greatly improved using spread-spectrum modulation techniques. This article proposes a family of reduced common-voltage sigma–delta modulations (RCMV- S¿ ) for voltage source converters (VSC) that use gallium nitride (GaN) semiconductors. Specifically, this article proposes three new techniques: two reduced-state sigma–delta modulations (RS- S¿1 &2), and an active sigma–delta strategy (A- S¿ ). The proposed modulation techniques reduce or eliminate the common-mode voltage (CMV) dv/dt transitions and suppress the noise spikes in the conducted electromagnetic interference spectrum. Furthermore, this article proposes the use of fast-processing quantizers for RCMV- S¿ techniques as well as for hexagonal sigma–delta (H- S¿ ). These quantizers use a novel calculation methodology that simplifies the implementation of the proposed modulations and considerably reduces their computational cost. The performance and the total harmonic distortion (THD) of RCMV- S¿ techniques are analyzed here using MATLAB/Simulink and PLECS. Experimental results performed on a VSC converter that uses GaN e-HEMTs show how RCMV- S¿ techniques considerably improve electromagnetic compatibility and exhibit similar efficiencies and THD to those of H- S¿ ., This work was supported by the Industrial Doctorates Plan of the Secretaria d’Universitats i Recerca del Departament d’Empresa i Coneixement de la Generalitat de Catalunya, the Centro para el Desarrollo Tecnológico Industrial (IDI-20200864), and in part by the Ministerio de Ciencia, Innovación y Universidades of Spain under Project PID2019-111420RB-I00., Peer Reviewed, Postprint (published version)

We present a novel formulation of closed-loop adaptive optics (AO) control as a multi-agent reinforcement learning (MARL) problem in which the controller is able to learn a non-linear policy and does not need a priori information on the dynamics of the atmosphere. We identify the different challenges of applying a reinforcement learning (RL) method to AO and, to solve them, propose the combination of model-free MARL for control with an autoencoder neural network to mitigate the effect of noise. Moreover, we extend current existing methods of error budget analysis to include a RL controller. The experimental results for an 8m telescope equipped with a 40x40 Shack-Hartmann system show a significant increase in performance over the integrator baseline and comparable performance to a model-based predictive approach, a linear quadratic Gaussian controller with perfect knowledge of atmospheric conditions. Finally, the error budget analysis provides evidence that the RL controller is partially compensating for bandwidth error and is helping to mitigate the propagation of aliasing., Funding: European Commission (871669, 873120)., Peer Reviewed, Postprint (published version)

We present a model-free reinforcement learning (RL) predictive model with a supervised learning non-linear reconstructor for adaptive optics (AO) control with a pyramid wavefront sensor (P-WFS). First, we analyse the additional problems of training an RL control method with a P-WFS compared to the Shack-Hartmann WFS. From those observations, we propose our solution: a combination of model-free RL for prediction with a non-linear reconstructor based on neural networks with a U-net architecture. We test the proposed method in simulation of closed-loop AO for an 8m telescope equipped with a 32x32 P-WFS and observe that both the predictive and non-linear reconstruction add additional benefits over an optimised integrator., This project has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 873120., Peer Reviewed, Postprint (author's final draft)

Non-destructive techniques can be used to assess the properties of FRC instead of performing tests that may increase testing time and material waste. Such techniques are oriented for both fresh and hardened state, enabling to evaluate and determine valuable parameters of FRC performance., Peer Reviewed, Postprint (published version)

La docencia en diseño de instalaciones químicas del Master Universitario en Ingeniería Química de la UA se basa en el Aprendizaje Basado en Proyectos (ABP). Los alumnos deben desarrollar un proyecto real durante el curso aplicando los nuevos conocimientos y destrezas adquiridos. La principal dificultad para el profesorado con esta metodología es lograr una adecuada comunicación de un gran número de datos, condicionantes y premisas relacionados con el proyecto planteado a los estudiantes. La finalidad última del proyecto es la mejora en la docencia y en la aplicación de la metodología ABP, facilitando un medio adecuado para abordar el planteamiento y desarrollo del proyecto en el que se basa el ABP. Para ello, se han desarrollado diversos videos que permiten la transmisión efectiva de información adicional que difícilmente logra transmitirse por otros medios. Se facilita a los alumnos acceso a materiales e información acorde a la realidad de la actividad profesional que realizarán en su futuro laboral. También se anima al alumnado a ampliar la información y datos necesarios por su cuenta para lograr una solución óptima. Finalmente, la encuesta de evaluación ha mostrado una valoración muy positiva del conjunto de la experiencia.

Accumulating evidence suggests that warming associated with climate change is decreasing the total amount of soil organic carbon (SOC) in drylands, although scientific research has not given enough emphasis to particulate (POC) and mineral-associated organic carbon (MAOC) pools. Biocrusts are a major biotic feature of drylands and have large impacts on the C cycle, yet it is largely unknown whether they modulate the responses of POC and MAOC to climate change. Here, we assessed the effects of simulated climate change (control, reduced rainfall (RE), warming (WA), and RE + WA) and initial biocrust cover (low (< 20%) versus high (> 50%)) on the mineral protection of soil C and soil organic matter quality in a dryland ecosystem in central Spain for 9 years. At low initial biocrust cover levels, both WA and RE + WA increased SOC, especially POC but also MAOC, and promoted a higher contribution of carbohydrates, relative to aromatic compounds, to the POC fraction. These results suggest that the accumulation of soil C under warming treatments may be transitory in soils with low initial biocrust cover. In soils with high initial biocrust cover, climate change treatments did not affect SOC, neither POC nor MAOC fraction. Overall, our results indicate that biocrust communities modulate the negative effect of climate change on SOC, because no losses of soil C were observed with the climate manipulations under biocrusts. Future work should focus on determining the long-term persistence of the observed buffering effect by biocrust-forming lichens, as they are known to be negatively affected by warming.

[Background] Mortality of pulmonary hypertension associated with congenital heart disease (PAH-CHD) in adults remains high., [Objectives] To identify predictors of death and to assess the impact of treatment on outcome., [Methods] Retrospective, multicenter cohort study of 103 adults with PAH-CHD followed-up for 8.6 ± 4.6 years. Patients were grouped according to underlying shunt type into pre-tricuspid, post-tricuspid and complex. Survival rates were analyzed and predictors of death were investigated with Cox regression models., [Results] In the post-tricuspid and complex groups (38 and 37 patients, respectively), the most common clinical PAH-CHD subgroup was Eisenmenger syndrome (76.3% and 59.5%, respectively) whereas, in the pre-tricuspid group (28 patients), 46.5% of patients had small or corrected defects. Overall, 88 patients received vasodilators; 39% required combination-therapy. Overall survival at 10 years was 65%. Mortality was highest in the pre-tricuspid group, FC-III-IV and amongst patients receiving monotherapy (p < 0.050). On multivariate analysis, predictors of poor outcome were pericardial effusion (HR: 4,520 [1,470–13,890]; p = 0,008), oxygen saturation(HR: 0.940 [0,900 - 0,990]; p = 0,018) and genetic syndromes(HR: 3,280 [1,098–9,780]; p = 0,033)., [Conclusions] Patients in advanced stages at initiation of treatment were at high risk of death and strong consideration should be given for more aggressive therapy.

This paper presents the material and process-related research that underpinned the realisation of the Parque de Castilla Footbridge in Madrid in 2016, going from the laboratory to the industrial scale. The fibre-reinforced cement-based composite was first developed and tested in a small-scale particle bed printer focusing on evaluating the influence of the material and process on the mechanical response and density of the printed parts. The solution was then upscaled to a full-size particle bed printer that underwent technical modifications to ensure adequate control and production quality of the footbridge segments. The observations derived from the study provide valuable insights on relevant process-related differences induced by the technology upscaling that can inform future applications of the technology., The authors acknowledge ACCIONA, S.A., for the funds provided. The authors also acknowledge Mr. Enrico Dini for his seminal role in the popularisation and visibility of particle bed 3D printing, holding the Application Patents of this system. The experimental program carried out at the Laboratory of Structures and Materials (LATEM) of the Polytechnic University of Catalonia (UPC, BarcelonaTECH) allowed identifying the parameters that govern the mechanical performance of the fibre reinforced cement-based composite designed and oriented to the manufacturing of structural components with particle bed 3D-printing systems. Additionally, the first and third author want to express their gratitude to AGAUR-FEDER for the financial support through the project 2019PROD00066., Peer Reviewed, Postprint (published version)

During the Early Middle Ages, most of the Iberian Peninsula became part of the so-called dār al-Islam, the huge realm that extended from the shores of the Atlantic to the borders of the Indian subcontinent, and which comprised North Africa, the Near East and significant parts of Central Asia. In the long run, this meant a dramatic shift from the notions, ideologies and frames of reference that emerged in other western regions of the former Roman Empire. Not withstanding this obvious divergence, Iberia had shared with these regions a common classical legacy that was assimilated, readapted and, finally, integrated after the Arab conquest under a new perspective in a number of distinctive ways. The aim of this paper is to analyse receptions, perceptions and ideas on classical Antiquity from the eighth to the tenth century in both al-Andalus and the Christian north, drawing data from the material evidence and the written record. It is our contention that the appreciation of this legacy underwent significant changes in both cultural milieus as a result of changing political and social circumstances.

Durante la segunda mitad del siglo x, el califato de Córdoba se convirtió en la mayor potencia política y cultural de Occidente. Lugar de visita de embajadas y comerciantes llegados desde todos los confines del Mediterráneo, al-Andalus conoció un gran esplendor. El cénit de esa supremacía se produjo en tiempos del califa al-Ḥakam II (961-976), famoso por poseer una de las mayores bibliotecas de la época, por sus obras de ampliación de la mezquita de Córdoba, y por la suntuosidad de la ciudad palatina en la que vivió, Madīnat al-Zahrāʼ, situada a pocos kilómetros de la capital., Este libro se basa en un texto extraordinario, que nunca había sido objeto de un estudio completo: los anales que un funcionario y cronista de la corte del califa escribió de forma casi diaria entre junio del 971 y julio del 975, lo que permite ofrecer un gran fresco del califato omeya de la mano de un testigo presencial. Es posible seguir los pasos del califa y su séquito a través del plano actual de Córdoba o de las ruinas, hoy visibles, de Madīnat al-Zahrāʼ, y comprobar el funcionamiento de la administración califal o los graves problemas del ejército en las guerras que mantenía en el norte de Marruecos y en la frontera contra los cristianos en el valle del Duero., Eduardo Manzano nos ayuda a comprender lo que significó el califato de Córdoba y cuáles fueron las razones por las que acabó desapareciendo después de haber conseguido tales cotas de esplendor. Desde este punto de vista, nos ofrece las claves para entender el fracaso del califato de Córdoba, uno de los elementos que conducirán, a la larga, al final de la presencia musulmana en la península.

[EN] During the Umayyad period in al-Andalus (756-1031), textual sources describe a certain number of parties and jolly occasions. Amirs and caliphs took part in some of them as well as members of the Cordovan upper class. However, these celebrations never became an integral part of courtly culture, which was more dominated by ceremonial aspects. It was only during the late caliphal period that a new courtly culture emerged; a culture that was dominated by a celebration of pleasant life and a distinctive set of elements, which included debauchery, [ES] Durante la época omeya en al-Andalus (756-1031) las fuentes escritas citan cierto número de fiestas en las que participaron tanto los propios soberanos, como gentes de las clases principales cordobesas. Sin embargo, estas celebraciones nunca pasaron a formar parte de la cultura cortesana, que siempre estuvo dominada por los elementos asociados al ceremonial. Fue sólo durante la época califal tardía cuando apareció una nueva cultura cortesana; una cultura que estuvo dominada por la celebración de la vida apacible y por un conjunto de elementos que incluían también el desenfreno