José A. Sánchez

Climatic applicability of downdraught cooling in Europe

This study describes the work on the development of climatic applicability maps of downdraught cooling in Europe; this work is presented as an extension of the work developed in the PHDC project, 2008–2010. The approach is based on a set of maps, which are based on two related climatic characteristics: dry bulb temperature–wet bulb temperature (DBT−WBT) and 25°C−WBT, and in the cooling requirements for each location. The meaning of the climatic characteristics will be explained in the text; as the first climatic characteristic represents the potential of using the evaporative systems to cool the air, and the second one shows the potential of cooling the building with a system that theoretically could supply the air in wet bulb conditions. The potential opportunity of using different types of downdraught cooling solutions, such as passive downdraught evaporative cooling and hybrid downdraught cooling, as an alternative to conventional air conditioning was assessed for different climate regions. A detailed version of a part of the Europe map will be done in order to take into account the particularities of a country like Spain. This set of maps will show the same parameters but with more resolution. Finally, six cities representing major climatic regions were selected for climatic analysis. This resulted in the identification of three climate zones for downdraught cooling application in Europe, and the suggestion of appropriate design strategies for each one of them.

Analysis of a PHDC (Passive and Hybrid Downdraft Cooling) Experimental Facility in Seville and its Applicability to the Madrid Climate

Abstract The potential application of Passive and Hybrid Downdraught Cooling to residential buildings is explored using an experimental facility constructed and tested in Seville, Spain. The experiment was devised as a prototype of the downdraught evaporative cooling system for the Nottingham University entry to the 2010 Solar Decathlon Europe competition. The experiment shows that peak evaporative cooling is obtained with an airflow rate of 2000 m3/hour (about 25 air changes per hour) and an evaporation rate of 8 L/h of water. The resulting indoor temperature in the space can be from 1 to 2 degrees above the inlet temperature. Wind forces can improve the performance but are not reliable and the air supply inlet should therefore be baffled to prevent negative impacts. Naturally driven evaporative cooling requires a control system which can vary the water supply rate in response to changing internal and external conditions. The use of exhaust fans can provide reliable performance, irrespective of external wind pressures, which suggests that a hybrid system (a combination of naturally and fan driven airflow) will be more robust in responding to variable conditions.

Educación formal y acciones de agrupación y memoria en adultos: Un estudio microgenético

ResumenSe estudio la influencia de la educacion formal en el empleo de acciones de agrupacion y memoria en sujetos adultos. El trabajo tenia una doble perspectiva, transversal y microgenetica. Los sujetos pertenecian a tres niveles educativos y se les estudio a lo largo de cuatro dias, en dos pruebas de memorizacion y recuerdo y una prueba de categorization dirigida intercalada entre las anteriores. Los resultados mostraron la influencia esperada de la escolarizacion en el empleo de acciones de agrupacion y memoria asi como cambios a lo largo de las sesiones en el grupo intermedio. La interpretacion de los resultados se baso en las nociones de subordinacion de acciones mentales y de descontextualizacion de los instrumentos de mediacion.

Interacción social durante el recreo en preescolares: Un estudio observacional en un centro de acogida y una escuela ordinaria

ResumenEl presente estudio analizo las interacciones entre iguales de preescolares de un colegio ordinario y de un centro de acogida durante el tiempo de recreo. Los resultados mas significativos aparecieron en la orientacion social de la conducta, encontrandose marcadas diferencias tanto en la dimension social del juego como en las conductas de no juego desplegadas por los ninos. Se encontro una mayor tendencia al aislamiento y al juego solitario en el centro de acogida que en el centro ordinario. Esta tendencia, sin embargo, aparecio mas marcada en los ninos que en las ninas, las cuales no presentaron diferencias con las ninas de la muestra del centro ordinario en este aspecto. El juego funcional tambien aparecio en mayor medida en la muestra del centro de acogida. Todos los resultados trataron de ser explicados partiendo del analisis de la influencia de los contextos de desarrollo en el comportamiento de los ninos.

El papel de las interacciones entre iguales en el proceso de socialización: implicaciones educativas de un estudio transcultural del juego en preescolares holandeses y andaluces

ResumenEl presente articulo se basa en el estudio realizado en centros preescolares de Holanda y Andalucia. En el mismo se observo la conducta de juego de preescolares que asistian a centros urbanos y rurales de ambos paises. Los datos mostraron una clara diferencia en la orientacion social de la conducta de juego de los preescolares. El juego de los ninos holandeses tendia a ser mas individual y orientado a la exploracion del medio fisico. En cambio el juego de los ninos andaluces tenia una mayor orientacion social, es decir, estaba mas centrado en las relaciones entre los ninos. Esta tendencia general se veia reducida cuando se comparaban los centros urbanos, y ampliada en los centros rurales.Estos datos son consistentes con los encontrados por otros estudios transculturales que muestran que el juego de los ninos refleja el ambiente cultural de los mundos adultos en los que se desarrollan. En nuestro caso, las diferencias en las conductas de juego de los ninos se pueden interpretar en base a la orientac...

Motivación y aprendizaje escolar: una aproximación desde la teoría de la autoeficacia

ResumenEn el presente trabajo se reinterpreta el problema de la motivacion para el rendimiento academico desde una perspectiva cognitiva, fundamentada en la teoria de la autoeftcacia. Se hace hincapie en el papel de las expectativas de eficacia como mediadoras entre las habilidades y el rendimiento de los sujetos y se acentua el papel que juega la motivacion cognitivamente basada en el proceso de aprendizaje. Postulamos, asimismo, la necesidad de fomentar la autoevaluacion frente a la evaluacion externa y los sistemas que permitan el desarrollo de la motivacion intrinseca para el aprendizaje.

Palynological and geographical characterisation of Spanish oak honeydew honeys

Abstract The emergent market for honeydew honey mostly in Europe has prompted increasing requirements by consumers and the honey industry for the characterisation of this type of honey. This work is a contribution to the limited knowledge of honeydew honeys in Spain. Botanical characterisation was performed on 59 honeydew honey samples from professional beekeepers hives distributed within Spain. The quantitative analysis reveals more than 75% of the samples belong to Maurizio Classes II and III, and that, in general, the Spanish Quercus honeydew honeys are characterised by medium high pollen grain content (Pn; mean = 285 197) and honeydew elements (HDEs; mean = 15 850). The analysis also resulted in the identification of spores of several fungal genera (Alternaria, Cladosporium, Drechslera, Geotrichum, Phithomyces, Stemhylium, Torula, Ulocladium and Venturia). All honey samples had a smaller ratio of honeydew elements to pollen grain content (mean HDE/Pn = 0.12), and for the majority of samples (93%) the ratio HDE/Pn was very low (< 0.3), suggesting that this traditional ratio value should not be considered as an indicator of honeydew honeys. The qualitative analysis of the samples showed the presence of 73 taxa belonging to 38 families. Pollen grains of Quercus f., Rubus ulmifloius f., Campanula erinus gr., Capsella f., Cytisus scoparius f., Echium plantagineum gr., Cistus ladanifer f. or Castanea sativa, and, to a lesser extent, those of Crepis f.,Eucalyptus f., Senecio f., Halimium f., Erica australis, Plantago f., Salix triandra gr. and Centaurea calcitrapa gr. are representative of Spanish oak honeydew honeys.

A monitoring system for identification and validation of the energetic model of a building using Wireless Sensor Networks

Buildings are, at a large extent, responsible for the carbon footprint, and regulation laws are emerging to reduce it. To this end energy saving policies must be established per individual building, involving building analysis and modeling, model identification and validation, proposal of actions to improve the energy efficiency, estimation of energy savings using that building model, implementation of the improvement actions, and experimental verification of the energy savings. The final objective is not only a reduction in the greenhouse emission, but also to get monetary savings that make these improvement actions attractive to building owners or holders. A key element in this process is the ability of measuring a set of variables regarding energy consumption, climate, and operating conditions of the building, Wireless Sensor Networks (WSNs) is a suitable technology for this proposal, due to its installation easiness, low cost and good performance. In this paper, an application layer has been designed on top of a ZigBee protocol for identification and validation of the energetic model of a building for the purposes of increasing its energy efficiency. A practical implementation in the 20.000 m2 School of Engineering, University of Seville, is also shown where one hundred sensors were deployed in a section of the building. A hybrid network (wired and wireless) has been used to cover such a large area taking profit of existing infrastructure.

Ventilación natural: estudio aerodinámico mediante CFD de extractores pasivos y captadores de viento

La ventilacion natural se ha ganado protagonismo en los ultimos tiempos como una medida de ahorro de energia para edificios. Los dos principios fundamentales de ventilacion natural son el tiro natural por diferencia de temperatura, y la fuerza del viento. El articulo pretende analizar la aerodinamica de los captadores y extractores de viento mediante fluido-mecanica computacional, optimizando las geometrias de estos elementos, y dando como producto del trabajo un modelo simplificado para poder tenerlos en cuenta el calculo aeraulico de las instalaciones de ventilacion y climatizacion de los edificios. Concretamente, se caracteriza una base de geometrias de captacion de viento, y se elabora una guia para el diseno de geometrias de extraccion ofreciendo varias de ellas como producto del trabajo realizado.In recent years, natural ventilation has won popularity as an energy saving measure for buildings. There are two fundamental principles of natural ventilation: natural draft by temperature differences, and wind force. The purpose of the article is to analyze the aerodynamics of windcatchers and wind-extractors by means of computational fluid mechanics, optimizing the geometries of these elements, and giving a simplified model as a result of the work, so as to include it in the aeraulic calculation of the buildings’ air conditioning systems. Therefore, a base for wind catching geometries has been characterized, and a guide for the design of extraction geometries has been developed; several of them are offered as a result of the work undertaken.

Microstructural Characterization of Silver Nanoparticles for Bioimaging Applications

Silver nanoparticles are emerging as a powerful tool in bioimaging applications owing to their unique plasmonic properties i.e., extremely high molar extinction coefficients, resonant Rayleigh scattering and enhanced local electromagnetic fields. Through the optimization of these properties, by controlling composition, size, shape, and interparticle spacing of nanoparticles and their assemblies, highly enhanced local electromagnetic fields in the vicinity of nanoparticles are achievable giving rise to IR, Raman and fluorescence surface enhanced spectroscopies (SEIRS, SERS and MEF, respectively).