165 research outputs found

    Jornada d'avaluació de la qualitat de les universitats

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    WEASEL: Vodafone Corporate Semantic Web

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    The 2006 Gartner emerging technology curve highlights the relevance of the Corporate Semantic Web as one of the most promising IT areas in the next five years. The work presented herein describes WEASEL, an initiative funded by Vodafone to apply and evaluate such technology in the context of a large multinational company. This scenario comprises a number of heterogeneous web sites containing unstructured and related, but physically decoupled, information which needs common models that provide unified ways of representing information across the different sources, i.e. ontologies. Three main milestones were defined for WEASEL: the creation of a domain ontology, the extraction of information from the different sources and its semantic annotation and aggregation, and the creation of a new web site containing a semantic search engine which provides natural interfaces for retrieving the aggregated information. WEASEL concluded with its evaluation by Vodafone

    Detecting broken Absorber Tubes in CSP plants using intelligent sampling and dual loss

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    Concentrated solar power (CSP) is one of the growing technologies that is leading the process of changing from fossil fuels to renewable energies. The sophistication and size of the systems require an increase in maintenance tasks to ensure reliability, availability, maintainability and safety. Currently, automatic fault detection in CSP plants using Parabolic Trough Collector systems evidences two main drawbacks: 1) the devices in use needs to be manually placed near the receiver tube, 2) the Machine Learning-based solutions are not tested in real plants. We address both gaps by combining the data extracted with the use of an Unmaned Aerial Vehicle, and the data provided by sensors placed within 7 real plants. The resulting dataset is the first one of this type and can help to standardize research activities for the problem of fault detection in this type of plants. Our work proposes supervised machine-learning algorithms for detecting broken envelopes of the absorber tubes in CSP plants. The proposed solution takes the class imbalance problem into account, boosting the accuracy of the algorithms for the minority class without harming the overall performance of the models. For a Deep Residual Network, we solve an imbalance and a balance problem at the same time, which increases by 5% the Recall of the minority class with no harm to the F1-score. Additionally, the Random Under Sampling technique boost the performance of traditional Machine Learning models, being the Histogram Gradient Boost Classifier the algorithm with the highest increase (3%) in the F1-Score. To the best of our knowledge, this paper is the first providing an automated solution to this problem using data from operating plants

    On the relevant role of solids residence time on their CO2 capture performance in the Calcium Looping technology

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    The multicycle CO capture performance of CaO derived from natural limestone and dolomite has been investigated by means of thermogravimetry under realistic Calcium-Looping conditions, which necessarily involve high CO concentration and high temperatures in the calcination stage and fast transitions between the carbonation and calcination stages. Natural dolomite allows reducing the calcination temperature as compared to limestone while high calcination efficiency is maintained. This could help reducing the energy penalty of the CaL process thus further enhancing the industrial competitiveness for the integration of this technology into fossil fuel power plants. Importantly, the CO capture capacity of the sorbents is critically affected by the solids residence time in the carbonation and calcination stages within the feasible range in practice. Thus, carbonation/calcination residence times play a critical role on the multicycle CO capture performance, which has been generally dismissed in previous studies. A main observation is the enhancement of carbonation in the solid-state diffusion controlled phase, which is against the commonly accepted conception that the only relevant phase in the carbonation stage is the fast reaction-controlled stage on the surface of the solids. Thus, the CO capture efficiency may be significantly enhanced by increasing the solids residence time in the carbonator.Ministerio de Economía y Competitividad CTQ2014-52763-C2-2-R, CTQ2014-52763-C2-1-RJunta de Andalucía FQM-5735, TEP-785

    Inteligencia emocional y mediadores motivacionales en una temporada de Educación Deportiva sobre mimo

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    During the course of a mime season, the effects of the Sport Education model (ED) on students’ emotional intelligence (attention, clarity and repair) and motivational mediators (relationship, autonomy, and perceived competence) were explored. A quasi-experimental study was conducted with pretest-posttest measures, in which 94 students (50 males, 44 females) 6th year of primary education, with an average age of 11.62 years (SD = ,79), were distributed in experimental and control groups. Qualitative instruments were used to deepen further the dependent variables in the experimental group: teacher dairy, and teacher and students interviews. Students on ED group obtained significant improvements in all dependent variables, surpassing the control group. Qualitative analysis confirmed these results. Results extend the evidence for ED model to address a traditionally undervalued content in physical education, such as body language (mime), and suggest the alliance between the ED model and the content in order to multiply the desired positive effects in terms of psychosocial development and well-being.Se exploraron los efectos del modelo de Educación Deportiva (ED) durante el desarrollo de una temporada de mimo en la inteligencia emocional (atención, claridad y reparación) y los mediadores motivacionales (relación, autonomía y competencia percibida) de los estudiantes. Se realizó un diseño cuasi-experimental con medidas pretest-postest, en el que 94 estudiantes (50 varones; 44 mujeres) de 6º curso de Educación Primaria, con una media de 11,62 años de edad (DT = ,79) fueron distribuidos en grupo experimental y control. En el grupo experimental se emplearon adicionalmente instrumentos cualitativos: diario del docente y entrevistas a estudiantes y profesor. Los estudiantes del modelo ED obtuvieron mejoras significativas en todas las variables dependientes, superando a las del grupo control. Los análisis cualitativos confirmaron esos resultados. Los resultados extienden la evidencia en favor del modelo de ED al abordar un contenido tradicionalmente minusvalorado en Educación Física, como es la expresión corporal (mimo), y sugieren la alianza del modelo y contenido al objeto de multiplicar efectos deseados positivos en términos de desarrollo psicosocial y bienestar personal

    Integrated analysis of the health and social inequalities of Spanish adolescents

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    Este estudio descriptivo presenta el proceso hasta la creación de una puntuación global de la salud en los adolescentes. En los últimos años, el concepto de salud, en el que se basa este estudio, ha sufrido cambios para incluir tanto los elementos disfuncionales como las fortalezas que protegen la salud. La muestra estuvo formada por 18.955 adolescentes, representativos de la población de 11 a 18 años en España y en cada una de las Comunidades Autónomas que conforman el Estado español. Utilizando técnicas de análisis factorial exploratorio y confirmatorio, los resultados mostraron una dimensión global de la salud, a partir de indicadores autoinformados de satisfacción vital, calidad de vida relacionada con la salud, percepción del estado general de salud y malestar psicosomático. Esta puntuación de salud disminuía a medida que aumentaba la edad y de manera más marcada en mujeres, así como en adolescentes de familias con capacidad adquisitiva baja. Los análisis comparativos entre Comunidades Autónomas mostraron diferencias entre ellas, no atribuibles en principio al bienestar económico de la región. Finalmente, se discutieron estos resultados y sus implicaciones, así como la importancia de la medida utilizada en el análisis de las desigualdades sociales en salud.This survey descriptive study presents the process leading up to the creation of a global health score for adolescents. In recent years, the concept of health, which is the bases for this study, has undergone changes to include both dysfunctional elements as well as the individual resources that protect health. The sample was made up of 18,955 adolescents between 11 to 18 years of age, in Spain and with participants in each of the regions making up the kingdom of Spain. Using exploratory and confirmatory factorial analysis techniques, the results showed a global dimension of the health, starting from self-report indicators of life satisfaction, health-related quality of life, perception of the general state of health and psychosomatic complaints. This health score decreased as age increased and more notably among girls, as well as in adolescents from low-income families. The comparative analyses between regions showed differences which were, in principle, not attributable to the economic well-being of the geographic area. Finally, these results and their implications were discussed, as well as the importance of the calculation used in the analysis of the social inequalities in health

    Calcium-Looping performance of steel and blast furnace slags for thermochemical energy storage in concentrated solar power plants

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    The Calcium Looping (CaL) process, based on the carbonation/calcination of CaO, has been proposed as a feasible technology for Thermochemical Energy Storage (TCES) in Concentrated Solar Power (CSP) plants. The CaL process usually employs limestone as CaO precursor for its very low cost, non-toxicity, abundance and wide geographical distribution. However, the multicycle activity of limestone derived CaO under relevant CaL conditions for TCES in CSP plants can be severely limited by pore plugging. In this work, the alternative use of calcium-rich steel and blast furnace slags after treatment with acetic acid is investigated. A main observation is that the calcination temperature to regenerate the CaO is significantly reduced as compared to limestone. Furthermore, the multicycle activity of some of the slags tested at relevant CaL conditions for TCES remains high and stable if the treated samples are subjected to filtration. This process serves to remove silica grains, which helps decrease the porosity of the CaO resulting from calcination in the mesoporous range thus mitigating pore plugging.Ministerio de Economia y Competitividad CTQ2014-52763-C2-2-R, CTQ2014-52763-C2-1-

    The “Alluvial Mesovoid Shallow Substratum”, a new subterranean habitat

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    Received: April 5, 2013; Accepted: August 23, 2013; Published: October 4, 2013In this paper we describe a new type of subterranean habitat associated with dry watercourses in the Eastern Iberian Peninsula, the “Alluvial Mesovoid Shallow Substratum” (alluvial MSS). Historical observations and data from field sampling specially designed to study MSS fauna in the streambeds of temporary watercourses support the description of this new habitat. To conduct the sampling, 16 subterranean sampling devices were placed in a region of Eastern Spain. The traps were operated for 12 months and temperature and relative humidity data were recorded to characterise the habitat. A large number of species was captured, many of which belonged to the arthropod group, with marked hygrophilous, geophilic, lucifugous and mesothermal habits. In addition, there was also a substantial number of species showing markedly ripicolous traits. The results confirm that the network of spaces which forms in alluvial deposits of temporary watercourses merits the category of habitat, and here we propose the name of “alluvial MSS”. The “alluvial MSS” may be covered or not by a layer of soil, is extremely damp, provides a buffer against above ground temperatures and is aphotic. In addition, compared to other types of MSS, it is a very unstable habitat. It is possible that the “alluvial MSS” may be found in other areas of the world with strongly seasonal climatic regimes, and could play an important role as a biogeographic corridor and as a refuge from climatic changes.The Spanish Ministry of Science and Innovation for funded this research project (CGL2010-19924) and the Ministry of Education and Science programme "Juan de la Cierva". This research Project (CGL2010-19924) was funded by the Spanish Ministry of Science and Innovation.The Ministry of Education and Science programme "Juan de la Cierva" funded the research activity of one of the authors (A. J-V.).Peer reviewe

    Mineral composition of bee pollen and its relationship with botanical origin and harvesting period

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    Producción CientíficaIn the present study, the mineral composition of seventy-one bee pollen samples from four different apiaries was determined by means of inductively coupled plasma-optical emission spectrometry. The results showed that there were no significant differences in relation to the overall mineral content per sample in terms of the apiary of origin or the harvesting period; the most common elements were phosphorus and potassium with concentrations ranging from 2.3 to 5.1 g/kg (dry weight). Moreover, the mineral content of the samples analyzed was similar to or higher than the recommended as well-balanced food for bees. Regarding the nutritional value for humans, bee pollen samples could be considered as a food rich in copper, iron, magnesium, manganese, and phosphorus. Finally, a canonical discriminant analysis was performed, and it was found that the apiary of origin could be distinguished by using the first three canonical functions; furthermore, over 90% of the samples could be correctly assigned to their corresponding apiary. The results were even better as regards the harvesting period, as only the first two canonical functions were sufficient to make a distinction between the different harvesting periods, resulting in a perfect match (100% of success rate).Ministerio de Economía y Competitividad (RTI2018-096268-B-100)Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (RTA 2015-00013-C03-01 and 03)FEDER and FSE (project AGRISOST-CM S2018/BAA-4330

    CO2 capture performance of Ca-Mg acetates at realistic Calcium Looping conditions

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    The Calcium Looping (CaL) process, based on the cyclic carbonation/calcination of CaO, has emerged in the last years as a potentially low cost technique for CO2capture at reduced energy penalty. In the present work, natural limestone and dolomite have been pretreated with diluted acetic acid to obtain Ca and Ca-Mg mixed acetates, whose CO2capture performance has been tested at CaL conditions that necessarily imply sorbent regeneration under high CO2partial pressure. The CaL multicycle capture performance of these sorbents has been compared with that of CaO directly derived from limestone and dolomite calcination. Results show that acetic acid pretreatment of limestone does not lead to an improvement of its capture capacity, although it allows for a higher calcination efficiency to regenerate CaO at reduced temperatures (∼900 °C) as compared to natural limestone (>∼930 °C). On the other hand, if a recarbonation stage is introduced before calcination to reactivate the sorbent, a significantly higher residual capture capacity is obtained for the Ca-Mg mixed acetate derived from dolomite as compared to either natural dolomite or limestone. The main reason for this behavior is the enhancement of carbonation in the solid-state diffusion controlled phase. It is argued that the presence of inert MgO grains in the mixed acetate with reduced segregation notably promotes solid state diffusion of ions across the porous structure created after recarbonation.Ministerio de Economia y Competitividad CTQ2014-52763-C2-2-R, CTQ2014-52763-C2-1-RJunta de Andalucía FQM-5735, TEP-785
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