934 research outputs found

    Multilingual opinion mining

    Get PDF
    170 p.Cada día se genera gran cantidad de texto en diferentes medios online. Gran parte de ese texto contiene opiniones acerca de multitud de entidades, productos, servicios, etc. Dada la creciente necesidad de disponer de medios automatizados para analizar, procesar y explotar esa información, las técnicas de análisis de sentimiento han recibido gran cantidad de atención por parte de la industria y la comunidad científica durante la última década y media. No obstante, muchas de las técnicas empleadas suelen requerir de entrenamiento supervisado utilizando para ello ejemplos anotados manualmente, u otros recursos lingüísticos relacionados con un idioma o dominio de aplicación específicos. Esto limita la aplicación de este tipo de técnicas, ya que dicho recursos y ejemplos anotados no son sencillos de obtener. En esta tesis se explora una serie de métodos para realizar diversos análisis automáticos de texto en el marco del análisis de sentimiento, incluyendo la obtención automática de términos de un dominio, palabras que expresan opinión, polaridad del sentimiento de dichas palabras (positivas o negativas), etc. Finalmente se propone y se evalúa un método que combina representación continua de palabras (continuous word embeddings) y topic-modelling inspirado en la técnica de Latent Dirichlet Allocation (LDA), para obtener un sistema de análisis de sentimiento basado en aspectos (ABSA), que sólo necesita unas pocas palabras semilla para procesar textos de un idioma o dominio determinados. De este modo, la adaptación a otro idioma o dominio se reduce a la traducción de las palabras semilla correspondientes

    Superconductivity-induced features in electronic Raman spectrum of monolayer graphene

    Get PDF
    Using the continuum model, we investigate theoretically contribution of the low-energy electronic excitations to the Raman spectrum of superconducting monolayer graphene. We consider superconducting phases characterised by an isotropic order parameter in a single valley and find a Raman peak at a shift set by the size of the superconducting gap. The height of this peak is proportional to the square root of the gap and the third power of the Fermi level, and we estimate its quantum efficiency as I1014I\sim10^{-14}.Comment: 7 pages, 2 figure

    Forest connectivity restoration through reforestation: an integrated methodology for prioritizing agricultural lands and selecting reforestation species

    Get PDF
    Forest connectivity restoration is a major goal in natural resource planning. Given the high amount of abandoned cultivated lands, setting efficient methods for the reforestation of agricultural lands offers a good opportunity to face this issue. However, reforestations must be carefully planned, which poses two main challenges. In first place, to determine those agricultural lands that, once reforested, would meet more effectively the planning goals. As a further step, in order to grant the success of the activity, it is fairly advisable to select those tree species that are more adapted to each particular environment. Here we intend to give response to both requirements by proposing a sequential and integrated methodology that has been implemented in two Spanish forest districts, which are formed by several landscape types that were previously defined and characterized. Using the software Conefor Sensinode, a powerful tool for quantifying habitat availability that is based on graph theory concepts, we determined the landscapes where forest planning should have connectivity as a major concern and, afterwards, we detected the agricultural patches that would contribute most to enhance connectivity if they were reforested. The subsequent reforestation species assessment was performed within these priority patches. Using penalized logistic regressions we fitted ecological niche models for the Spanish native tree species. The models were trained with species distribution data from the Spanish Forest Map and used climatic and lithological variables as predictors. Model predictions were used to build ordered lists of suitable species for each priority patch. The lists include dominant and non dominant tree species and allow adding biodiversity goals to the reforestation planning. The result of this combined methodology is a map of agricultural patches that would contribute most to uphold forest connectivity if they were reforested and a list of suitable tree species for each patch ordered by occurrence probability. Therefore the proposed methodology may be useful for suitable and efficient forest planning and landscape designing

    Teacher evaluation in Colombia

    Full text link
    Los resultados de los sistemas educativos cada vez tienen una mayor relevancia en la sociedad a nivel mundial, una evidencia de ello es la prueba PISA. Esta evaluación tiene diversos efectos en los sistemas educativos, entre ellas destaca la evaluación del trabajo docente. Por esta razón, se ha focalizado la atención en evaluar la práctica docente desde la perspectiva de la rendición de cuentas. Para ello, se analiza el sistema de evaluación docente de Colombia, considerando el contexto educativo del país, así como sus resultados, además de la política implantada y el marco legal desde un punto de vista críticoThe results of educational systems are increasingly relevant in society worldwide, as evidenced by the PISA test. For this reason, attention has been focused on evaluating teaching practice from the perspective of accountability. This evaluation has various effects on education systems, among them the evaluation of teaching work. To achieve this, the evaluation system of teachers in Colombia is analyzed considering the educational context of the country, as well as its results, the policy implemented and the legal framework from a critical point of vie

    EduRom: Promoting the access of Roma to LLP, VET and employment through family education in Primary schools

    Get PDF
    Over the last two decades, it is apparent that the socio-economic situation of many Roma people has stagnated or even deteriorated in a number of EU Member States. Many Roma people experience unemployment, low income, reduced life expectancy and poor quality of life (Background document of the Final conference on the Adult Learning Action plan - 2011
    corecore