409 research outputs found

    Estudi del funcionament d'un sistema de generació elèctrica eòlica d'àmbit domèstic

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    El present treball pretén estudiar de forma genèrica les característiques que presenta un sistema de generació eòlica domèstica. Per a fer-ho s’ha dividit el contingut en dos grans blocs; un estudi de caracter macroscopi de l’energia que es produiria en un habitatge i un segon, de caràcter més tècnic, on s’analitza el control i el convertidor que requeriria tal sistema. Per al primer s’ha treballat amb dades d’un habitatge particular, en concret d’una casa al municipi de Capafonts propietat dels pares de l’autor del present treball. D’aquesta manera s’ha pogut disposar de dades de consum real. A més, les dades sobre velocitat i direcció del vent també s’ajusten a l’habitatge en qüestió, oferint així una visió més focalitzada però més real. Pel que fa la segona part, s’ha usat l’entorn MATLAB-Simulink per modelar un convertidor elèctric i el seu respectiu control. En el model s’hi ha inclòs el sistema de generació i un sistema d’emmagatzematge. S’han simulat diferents casos segons si la potència consumida es manté constant o no, segons si la producció elèctrica es manté constant o no, o segons si aquesta potència produïda és suficient per cobrir la demanda o, per contra, es requereix potència del sistema d’emmagatzematge

    A method for the automated Raman spectra acquisition.

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    Raman spectroscopy is a very powerful analytical technique with an increasing acceptance in the scientific community. For theoptimization of the Raman acquisition, two main parameters, the integration time and the number of accumulations, need tobe adjusted to the sample under analysis, as the sample, or even different spots on the same sample, can provide very differentRaman responses one from another. In this paper, we present a suite of algorithms to automate the acquisition parameteradjustment to the sample under analysis, addressing issues such as spectral saturation, fluorescence, cosmic ray detection andremoval, and adjustment of the acquisition parameters to optimize the acquired spectral data. This suite has been developedin the framework of the Raman Laser Spectrometer (RLS) instrument development for the Exomars mission but can be appliedto any Raman spectrometer. This will allow the spectrometer to adapt to the characteristics of the sample that is being analyzed,optimizing the total operative time, while improving the usability and overall efficiency of the system. Copyright © 2017 JohnWiley & Sons, Ltd.MINECO ESP2014-56138-C3-1-

    TINTIN : comprobación incremental de aserciones SQL

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    Ninguno de los SGBD más populares del momento implementa aserciones SQL, obligando así a implementar manualmente su comprobación. Por ello, presentamos TINTIN: una aplicación que genera automáticamente el código SQL para comprobar aserciones. Dicho código captura las tuplas insertadas/borradas en una transacción, comprueba que ninguna de ellas viole ninguna aserción mediante consultas SQL, y materializa los cambios en caso que sean satisfechas. La eficiencia del código se basa en la comprobación incremental de las aserciones.Peer ReviewedPostprint (published version

    Sustainable development in North Bohuslän (Sweden): an analysis in three scales

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    Partiendo del estudio de la zona que discurre por la carretera E6 en su recorrido desde el municipio de Uddevala, al suroeste de Suecia hasta la frontera con Noruega se analizan las afecciones producidas en los asentamientos y el paisaje. El proyecto se estructura en tres escalas diferentes: regional, intermedia y local para entender la fuerte conexión entre las mismas. A nivel regional se analizan los tipos de paisaje por medio de un inventario utilizando el método PEBOSCA, dentro del programa Hábitat de las Naciones Unidas estudiando todos los recursos (físicos, biológicos, sociales, económicos, organizacionales... ) de una zona determianda ; y el método DAFO (en inglés SWOT)que se ocupa de las fuerzas y debilidades de la región. Se identifican los problemas más importantes, a saber, ampliar los servicios durante todo el año, mejorar la conectividad extendiendo el transporte público y carriles para bicicletas y mejorar la calidad del agua mitigando su efecto barrera. En un nivel intermedio, el proyecto se centra en la localidad de Hogdalsnäset por estar afectado por una falta de estructura urbana y por su proximidad a la frontera con Noruega. En el plano local se analiza la zona de Nordby presentando un plan alternativo de desarrollo a corto, medio y largo plazo. Por último, la autora concluye con la propuesta de construcción del "Parque del Humedal"

    Age-Related Relationships between Innate Immunity and Plasma Carotenoids in an Obligate Avian Scavenger

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    14 páginas, 2 figuras, 2 tablasVariation in immunity is influenced by allocation trade-offs that are expected to change between age-classes as a result of the different environmental and physiological conditions that individuals encounter over their lifetime. One such trade-off occurs with carotenoids, which must be acquired with food and are involved in a variety of physiological functions. Nonetheless, relationships between immunity and carotenoids in species where these micronutrients are scarce due to diet are poorly studied. Among birds, vultures show the lowest concentrations of plasma carotenoids due to a diet based on carrion. Here, we investigated variations in the relationships between innate immunity (hemagglutination by natural antibodies and hemolysis by complement proteins), pathogen infection and plasma carotenoids in nestling and adult griffon vultures (Gyps fulvus) in the wild. Nestlings showed lower hemolysis, higher total carotenoid concentration and higher pathogen infection than adults. Hemolysis was negatively related to carotenoid concentration only in nestlings. A differential carotenoid allocation to immunity due to the incomplete development of the immune system of nestlings compared with adults is suggested linked to, or regardless of, potential differences in parasite infection, which requires experimental testing. We also found that individuals with more severe pathogen infections showed lower hemagglutination than those with a lower intensity infection irrespective of their age and carotenoid level. These results are consistent with the idea that intraspecific relationships between innate immunity and carotenoids may change across ontogeny, even in species lacking carotenoid-based coloration. Thus, even low concentrations of plasma carotenoids due to a scavenger diet can be essential to the development and activation of the immune system in growing birds.Funds were provided by the projects CGL2009-12753-C02-01/BOS and CGL2010-15726 of Spanish Ministerio of Economía y Competitividad. DHM is member of the IBERCAROT Network, funded by CYTED (ref. 112RT0445).Peer reviewe

    GROM: a general rewriter of semantic mappings

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    We present GROM, a tool conceived to handle high-level schema mappings between semantic descriptions of a source and a target database. GROM rewrites mappings between the virtual, view-based semantic schemas, in terms of mappings between the two physical databases, and then executes them. The system serves the purpose of teaching two main lessons. First, designing mappings among higher-level descriptions is often simpler than working with the original schemas. Second, as soon as the view-definition language becomes more expressive, to handle, for example, negation, the mapping problem becomes extremely challenging from the technical viewpoint, so that one needs to find a proper trade-off between expressiveness and scalability.Peer ReviewedPostprint (published version

    Male quality and conspecific scent preferences in the house finch, Carpodacus mexicanus

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    Received 7 June 2012, Revised 10 July 2012, Accepted 10 September 2012, Available online 16 October 2012There is increasing evidence that birds use chemical cues in different contexts, and this is changing the traditional view that birds are the only largely olfaction-free vertebrates. We performed a choice experiment to examine whether male house finches exhibit any preferences for the sex of conspecifics when only their chemical cues are available. When exposed during the breeding season to the scent of a male and a female, males appeared to respond indiscriminately to both odours. However, when we analysed a posteriori the choices of males in relation to their relative quality, males with worse quality than scent donor males avoided the male-scented area, whereas males with better quality moved towards the male-scented area. Our results suggest that in the context of mate choice/competition for mates, house finches may obtain information via olfaction to assess the quality of rival males.L.R was supported by a postdoctoral fellowship from CSIC-UNAM (Spain-Mexico)Peer reviewe

    Validation of schema mappings with nested queries

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    With the emergence of the Web and the wide use of XML for representing data, the ability to map not only flat relational but also nested data has become crucial. The design of schema mappings is a semi-automatic process. A human designer is needed to guide the process, choose among mapping candidates, and successively refine the mapping. The designer needs a way to figure out whether the mapping is what was intended. Our approach to mapping validation allows the designer to check whether the mapping satisfies certain desirable properties. In this paper, we focus on the validation of mappings between nested relational schemas, in which the mapping assertions are either inclusions or equalities of nested queries. We focus on the nested relational setting since most XML’s Document Type Definitions (DTDs) can be represented in this model. We perform the validation by reasoning on the schemas and mapping definition. We take into account the integrity constraints defined on both the source and target schema.Preprin

    Testing Termination of Query Satisfiability Checking on Expressive Database Schemas

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    A query is satisfiable if there is at least one consistent instance of the database in which it has a non-empty answer. Defining queries on a database schema and checking their satisfiability can help the database designer to be sure whether the produced database schema is what was intended. The formulation of such queries may easily require the use of some arithmetic comparisons or negated expressions. Unfortunately, checking the satisfiability of this class of queries on a database schema that most likely have some integrity constraints (e.g., keys, foreign keys, Boolean checks) is, in general, undecidable. However, although the problem is undecidable for such a class of schemas and queries, it may not be so for a particular query satisfiability check. In this paper, we propose to perform a termination test as a previous step to query satisfiability checking. If positive, the termination test guarantees that the corresponding query satisfiability check will terminate. We assume the CQC method is the underlying query satisfiability checking method; to the best of our knowledge, it is the only method of this kind able to deal with schemas and queries as expressive as the ones we consider.Preprin

    A schema-only approach to validate XML schema mappings

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    Since the emergence of the Web, the ability to map XML data between different data sources has become crucial. Defining a mapping is however not a fully automatic process. The designer needs to figure out whether the mapping is what was intended. Our approach to this validation consists of defining and checking certain desirable properties of mappings. We translate the XML schemas and the mapping into first-order logic formalism and apply a reasoning mechanism to check the desirable properties automatically, without assuming any particular instantiation of the schemas.Preprin
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