36 resultados para CPG (Central pattern generator)


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[ES]Este proyecto se centra en el estudio y diseño de una central de generación de energía eléctrica por medio de biomasa forestal. La motivación para la realización de este proyecto reside en la gran importancia que en los últimos años están tomando las energías renovables. El Calentamiento Global es un hecho que durante los últimos años ha llevado a la investigación y desarrollo de las energías alternativas, que frenan o contribuyen al ralentizamiento de este fenómeno. Por su parte la implantación de una planta como la que se estudia a continuación, no solo ayudaría a la reducción de emisiones netas de CO2 a la atmósfera, sino que también tendría numerosas ventajas como son la creación de empleo, la limpieza de bosques, lo que ayuda a la prevención de incendios y plagas, y proporcionaría una independencia energética. Los pasos que se van a seguir en el proyecto son los siguientes:  Explicar el alcance y los objetivos del proyecto. Desarrollar las posibles alternativas que existen para la valorización de la biomasa forestal, incluyendo un resumen de las ventajas y desventajas que cada una presenta. Informe detallado de la alternativa seleccionada, la combustión, que incluye la explicación del proceso en la planta desde que el residuo sale del bosque, hasta la obtención de la energía eléctrica. Análisis económico y rentabilidad de la planta. Realizar el cronograma del proyecto. Por último se realizará un análisis de los posibles riesgos.

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This paper presents a method to generate new melodies, based on conserving the semiotic structure of a template piece. A pattern discovery algorithm is applied to a template piece to extract significant segments: those that are repeated and those that are transposed in the piece. Two strategies are combined to describe the semiotic coherence structure of the template piece: inter-segment coherence and intra-segment coherence. Once the structure is described it is used as a template for new musical content that is generated using a statistical model created from a corpus of bertso melodies and iteratively improved using a stochastic optimization method. Results show that the method presented here effectively describes a coherence structure of a piece by discovering repetition and transposition relations between segments, and also by representing the relations among notes within the segments. For bertso generation the method correctly conserves all intra and inter-segment coherence of the template, and the optimization method produces coherent generated melodies.

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Sex workers are traditionally considered important vectors of transmission of sexually transmitted infections (STI). The role of clients is commonly overlooked, partially due to the lack of evidence on clients' position in the sexual network created by commercial sex. Contrasting the diffusion importance of sex workers and their clients in the map of their sexual encounters in two Web-mediated communities, we find that from diffusion perspective, clients are as important as sex workers. Their diffusion importance is closely linked to the geography of the sexual encounters: as a result of different movement patterns, travelling clients shorten network distances between distant network neighborhoods and thus facilitate contagion among them more than sex workers, and find themselves more often in the core of the network by which they could contribute to the persistence of STIs in the community. These findings position clients into the set of the key actors and highlight the role of human mobility in the transmission of STIs in commercial sexual networks.

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The objective of the work was to develop a non-invasive methodology for image acquisition, processing and nonlinear trajectory analysis of the collective fish response to a stochastic event. Object detection and motion estimation were performed by an optical flow algorithm in order to detect moving fish and simultaneously eliminate background, noise and artifacts. The Entropy and the Fractal Dimension (FD) of the trajectory followed by the centroids of the groups of fish were calculated using Shannon and permutation Entropy and the Katz, Higuchi and Katz-Castiglioni's FD algorithms respectively. The methodology was tested on three case groups of European sea bass (Dicentrarchus labrax), two of which were similar (C1 control and C2 tagged fish) and very different from the third (C3, tagged fish submerged in methylmercury contaminated water). The results indicate that Shannon entropy and Katz-Castiglioni were the most sensitive algorithms and proved to be promising tools for the non-invasive identification and quantification of differences in fish responses. In conclusion, we believe that this methodology has the potential to be embedded in online/real time architecture for contaminant monitoring programs in the aquaculture industry.

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Several alpine vertebrates share a distribution pattern that extends across the South-western Palearctic but is limited to the main mountain massifs. Although they are usually regarded as cold-adapted species, the range of many alpine vertebrates also includes relatively warm areas, suggesting that factors beyond climatic conditions may be driving their distribution. In this work we first recognize the species belonging to the mentioned biogeographic group and, based on the environmental niche analysis of Plecotus macrobullaris, we identify and characterize the environmental factors constraining their ranges. Distribution overlap analysis of 504 European vertebrates was done using the Sorensen Similarity Index, and we identified four birds and one mammal that share the distribution with P. macrobullaris. We generated 135 environmental niche models including different variable combinations and regularization values for P. macrobullaris at two different scales and resolutions. After selecting the best models, we observed that topographic variables outperformed climatic predictors, and the abruptness of the landscape showed better predictive ability than elevation. The best explanatory climatic variable was mean summer temperature, which showed that P. macrobullaris is able to cope with mean temperature ranges spanning up to 16 degrees C. The models showed that the distribution of P. macrobullaris is mainly shaped by topographic factors that provide rock-abundant and open-space habitats rather than climatic determinants, and that the species is not a cold-adapted, but rather a cold-tolerant eurithermic organism. P. macrobullaris shares its distribution pattern as well as several ecological features with five other alpine vertebrates, suggesting that the conclusions obtained from this study might be extensible to them. We concluded that rock-dwelling and open-space foraging vertebrates with broad temperature tolerance are the best candidates to show wide alpine distribution in the Western Palearctic.

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In this paper, a real time sliding mode control scheme for a variable speed wind turbine that incorporates a doubly feed induction generator is described. In this design, the so-called vector control theory is applied, in order to simplify the system electrical equations. The proposed control scheme involves a low computational cost and therefore can be implemented in real-time applications using a low cost Digital Signal Processor (DSP). The stability analysis of the proposed sliding mode controller under disturbances and parameter uncertainties is provided using the Lyapunov stability theory. A new experimental platform has been designed and constructed in order to analyze the real-time performance of the proposed controller in a real system. Finally, the experimental validation carried out in the experimental platform shows; on the one hand that the proposed controller provides high-performance dynamic characteristics, and on the other hand that this scheme is robust with respect to the uncertainties that usually appear in the real systems.

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Background: In recent years Galaxy has become a popular workflow management system in bioinformatics, due to its ease of installation, use and extension. The availability of Semantic Web-oriented tools in Galaxy, however, is limited. This is also the case for Semantic Web Services such as those provided by the SADI project, i.e. services that consume and produce RDF. Here we present SADI-Galaxy, a tool generator that deploys selected SADI Services as typical Galaxy tools. Results: SADI-Galaxy is a Galaxy tool generator: through SADI-Galaxy, any SADI-compliant service becomes a Galaxy tool that can participate in other out-standing features of Galaxy such as data storage, history, workflow creation, and publication. Galaxy can also be used to execute and combine SADI services as it does with other Galaxy tools. Finally, we have semi-automated the packing and unpacking of data into RDF such that other Galaxy tools can easily be combined with SADI services, plugging the rich SADI Semantic Web Service environment into the popular Galaxy ecosystem. Conclusions: SADI-Galaxy bridges the gap between Galaxy, an easy to use but "static" workflow system with a wide user-base, and SADI, a sophisticated, semantic, discovery-based framework for Web Services, thus benefiting both user communities.

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Introducción: Los catéteres venosos centrales (CVC) de larga duración representan una alternativa para muchos pacientes receptores de tratamientos intravenosos prolongados y agresivos. Dentro de estos, es frecuente el uso de los reservorios venosos subcutáneos (RVS) y de los catéteres centrales de inserción periférica (PICC). En ambos, a pesar de sus numerosas ventajas, pueden surgir complicaciones que comprometan el funcionamiento del dispositivo y provocar la necesidad de retirarlo. Estas, además, pueden poner en peligro el bienestar e incluso la vida del paciente. Objetivos: Analizar las complicaciones asociadas a la implantación y uso de RVS y PICC. Metodología: Se realizó una búsqueda bibliográfica en las bases de datos: Scopus, ScienceDirect, Dialnet plus, ProQuest, OvidSP, SciELO, Cuiden y Elsevier. Resultados: Se seleccionaron seis estudios realizados sobre pacientes portadores de RVS y cinco sobre los PICC. En ellos se analizaron las complicaciones surgidas y los motivos de retirada de los dispositivos por complicaciones asociadas. Conclusiones: Los PICC presentan una morbilidad y una tasa de retirada por complicaciones mayor que los RVS. Las infecciones, obstrucciones y trombosis son las complicaciones con mayor prevalencia en ambos dispositivos junto con las extracciones accidentales en el caso de los PICC. Además, representan los motivos más habituales de retirada del CVC por alguna complicación. Las complicaciones pueden estar influenciadas por distintos factores, entre otros, los cuidados y mantenimiento que se realicen del dispositivo. Idioma: Español.

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A central question in Neuroscience is that of how the nervous system generates the spatiotemporal commands needed to realize complex gestures, such as handwriting. A key postulate is that the central nervous system (CNS) builds up complex movements from a set of simpler motor primitives or control modules. In this study we examined the control modules underlying the generation of muscle activations when performing different types of movement: discrete, point-to-point movements in eight different directions and continuous figure-eight movements in both the normal, upright orientation and rotated 90 degrees. To test for the effects of biomechanical constraints, movements were performed in the frontal-parallel or sagittal planes, corresponding to two different nominal flexion/abduction postures of the shoulder. In all cases we measured limb kinematics and surface electromyographic activity (EMB) signals for seven different muscles acting around the shoulder. We first performed principal component analysis (PCA) of the EMG signals on a movement-by-movement basis. We found a surprisingly consistent pattern of muscle groupings across movement types and movement planes, although we could detect systematic differences between the PCs derived from movements performed in each sholder posture and between the principal components associated with the different orientations of the figure. Unexpectedly we found no systematic differences between the figute eights and the point-to-point movements. The first three principal components could be associated with a general co-contraction of all seven muscles plus two patterns of reciprocal activatoin. From these results, we surmise that both "discrete-rhythmic movements" such as the figure eight, and discrete point-to-point movement may be constructed from three different fundamental modules, one regulating the impedance of the limb over the time span of the movement and two others operating to generate movement, one aligned with the vertical and the other aligned with the horizontal.

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Background: An accumulating body of evidence points to the significance of neuroinflammation and immunogenetics in schizophrenia, and an imbalance of cytokines in the central nervous system (CNS) has been suggested to be associated with the disorder. Munc18-overexpressing mice (Munc18-OE) have provided a model for the study of the alterations that may underlie the symptoms of subjects with schizophrenia. The aim of the present study was to elucidate the involvement of neuroinflammation and cytokine imbalance in this model. Methods: Cytokines were evaluated in the cortex and the striatum of Munc18-OE and wild-type (WT) mice by enzyme-linked immunosorbent assay (ELISA). Protein levels of specific microglia and macrophage, astrocytic and neuroinflammation markers were quantified by western blot in the cortex and the striatum of Munc18-OE and WT mice. Results: Each cytokine evaluated (Interferon-gamma (IFN-gamma), Tumor Necrosis Factor-alpha (TNF-alpha), Interleukin-2 (IL-2) and CCL2 chemokine) was present at higher levels in the striatum of Munc18-OE mice than WT. Cortical TNF-alpha and IL-2 levels were significantly lower in Munc18-OE mice than WT mice. The microglia and macrophage marker CD11b was lower in the cortexes of Munc18-OE mice than WT, but no differences were observed in the striatum. Glial Fibrillary Acidic Protein (GFAP) and Nuclear Factor-kappaB (NF-kappa B)p65 levels were not different between the groups. Interleukin-1beta (IL-1 beta) and IL-6 levels were beneath detection limits. Conclusions: The disrupted levels of cytokines detected in the brain of Munc18-OE mice was found to be similar to clinical reports and endorses study of this type for analysis of this aspect of the disorder. The lower CD11b expression in the cortex but not in the striatum of the Munc18-OE mice may reflect differences in physiological activity. The cytokine expression pattern observed in Munc18-OE mice is similar to a previously published model of schizophrenia caused by maternal immune activation. Together, these data suggest a possible role for an immune imbalance in this disorder.

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[ES]El proyecto consiste en el estudio de las necesidades energéticas de las bombas de una central hidráulica y la construcción de un parque eólico para satisfacer dichas necesidades. Para ello será necesario llevar a cabo un estudio del área y así encontrar el lugar más adecuado para ubicar los aerogeneradores, teniendo en cuenta la frecuencia, velocidad y dirección de los vientos predominantes del lugar. Después habrá que estudiar el mercado y elegir el aerogenerador adecuado para las condiciones del lugar y del viento, atendiendo también a otras cuestiones de relevancia. Se estudiará, además, la posibilidad de inyectar un posible exceso de electricidad a la red general. Una vez hecho esto, habrá que calcular el coste del proyecto.

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[ES]El objetivo de este proyecto es conocer el funcionamiento de la Central Hidroeléctrica de Bertxin – Leizarán y plantear alternativas económicamente viables para mejorar la eficiencia de la misma. Se analizará para cada una de las alternativas propuestas el efecto en el rendimiento de la central, así como el impacto económico estimado, atendiendo al precio de la obra y el equipo necesario. Así, se determinará la solución óptima, que será desarrollada en el anteproyecto.

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[ES]El objetivo del presente proyecto de viabilidad es estudiar la eficiencia y productividad de la central hidroeléctrica de Ubao – Toquillo, situada en Oñati, Gipuzkoa (España), ofreciendo a su vez una serie de alternativas económica y técnicamente viables. Para ello, se analizarán los elementos de la central; aunque la turbina hidráulica sea el elemento fundamental de la central, se tendrán en cuenta otros elementos como, por ejemplo, estructuras mecánicas o máquinas eléctricas. Para cada una de las alternativas, se calculará la producción de energía y la inversión necesaria, y se compararán unas con otras. Finalmente, se seleccionará la óptima que pasará a desarrollarse en el anteproyecto.

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[ES]El objetivo de este proyecto es intentar conseguir, mediante la energía que ofrece el mar, un sistema de energía eléctrica autónoma para un pueblo de la Costa Vasca. Para ello, es necesario un estudio que permita obtener el flujo de potencia y la dirección óptima donde situar la central undimotriz, así como el mejor sistema para su aprovechamiento.