1,414 research outputs found

    CFD model-based analysis and experimental assessment of key design parameters for an integrated unglazed metallic thermal collector façade

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    Active façade systems incorporating solar thermal collectors currently offer very promising energetic solutions. From among the available systems, a simple solution is the unglazed heat collector for potential integration in low-temperature applications. However, when adopting system definitions, the modification of some design parameters and their impact has to be fully understood. In this study, the case of an unglazed collector integrated into a sandwich panel is assessed and a specific analysis is performed for a proper assessment of the influence of key design parameters. Based on that case study of the real built system, a CFD model is developed and validated and a parametric assessment is then performed, by altering the configurations of both the panel and the hydraulic circuit. In this way, the potential of each measure to harness solar energy can be evaluated and each parameter with its different level of impact can be highlighted, to identify those of higher relevance. A characterization of the real solution completes the study, by providing the efficiency curves and the total energy collected during the experimental campaign. The maximum estimate of the efficiency of a 6 m2 façade was within a range between 0.47 and 0.34 and the heat loss factor was between 4.8 and 7.5. The case study exercises reveal the real energy efficiency and solar production patterns. There was also an opportunity to consider significant improvements to increase the output of the active façade. The main conclusions concerned the different criteria that improved the definition of the system and greater comprehension of alternative designs that may be integrated in the underlying concept.The authors are grateful to the Basque Government for fundingthis research through projects IT781-13 and IT1314-19 and to allthose involved in the different stages for their guidance andinvaluable help.The authors would also like to thank all those companies andresearchers participating in the BASSE project for their stronginvolvement during that research. Results from BASSE project haveinspired present research. The BASSE project received funding fromthe European Union, RFCS Program, Research Fund for Coal and Steel project Building Active Steel Skin (BASSE, Grant Agreement noRFSR-CT-2013-00026

    Human substantia nigra neurons encode unexpected financial rewards

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    The brain's sensitivity to unexpected outcomes plays a fundamental role in an\ud organism's ability to adapt and learn new behaviors. Emerging research suggests that\ud midbrain dopaminergic neurons encode these unexpected outcomes. We used\ud microelectrode recordings during deep brain stimulation surgery to study neuronal activity in\ud the human substantia nigra (SN) while patients with Parkinson's disease engaged in a\ud probabilistic learning task motivated by virtual financial rewards. Based on a model of the ..

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    Size effects on the Neél temperature of antiferromagnetic NiO nanoparticles

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    Among all antiferromagnetic transition metal monoxides, NiO presents the highest Neél temperature (TN ~ 525 K). In this work, the size-dependent reduction of TN in NiO nanoparticles with average diameters (D) ranging from 4 to 9 nm is investigated by neutron diffraction. The scaling law followed by TN(D) is in agreement with the Binder theory of critical phenomena in low-dimensional systems. X-ray absorption fine structure measurements link the decrease of TN to the occurrence of size effects (average undercoordination, bond relaxation and static disorder) in the nearest and next-nearest Ni coordination shells that hold the key for the maintenance of the antiferromagnetic order

    Clinical microbiological case: sore throat and painful bilateral lymph nodes

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    La formetría aplicada a las deformidades de la columna.

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    La forma de la espalda es un factor importante en la evaluación clínica de varias afecciones de la columna, en particular de la escoliosis. Se describe un método de análisis de la forma de la superficie de la espalda que fue ideado para conocer la mayoría de los parámetros necesarios para evaluar el progreso de la enfermedad en tanto afecte a la forma del cuerpo. La medición de la forma de la superficie de la espalda y de las marcas anatómicas manuales se analizan a través de un sistema de ordenador-monitor en el que se escanea el plano de luz incidente sobre la espalda y desde topografía moiré. Las marcas anatómicas se llevan a cabo para definir los planos de referencia desde los cuales se comparan sucesivos análisis. Este método se emplea para estimar los ángulos de las vértebras límites y los ángulos de Cobb. Las secciones laterales muestran la cifosis y lordosis. Para los resultados se han llevado a cabo correlaciones de la asimetría lateral de la forma de la superficie con el ángulo de Cobb medido mediante radiografía. Las mediciones se llevaron a cabo en tres grupos de pacientes (47 pacientes en total). El rango osciló entre r=0.66 a r=0.88, para una p<0.001. El análisis de los resultados podría reducir en un futuro los exámenes con rayos X en el evolutivo, por lo evidenciado cuantitativamente y con inocuidad total tanto en la asimetría lateral como en la deformidad en el plano transverso.Peer Reviewe
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