33 research outputs found

    Flexible Fuzzy Rule Bases Evolution with Swarm Intelligence for Meta-Scheduling in Grid Computing

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    Fuzzy rule-based systems are expert systems whose performance is strongly related to the quality of their knowledge and the associated knowledge acquisition processes and thus, the design of effective learning techniques is considered a critical and major problem of these systems. Knowledge acquisition with a swarm intelligence approach is a recent learning strategy for the evolution of fuzzy rule bases founded on swarm intelligence showing improvement over classical knowledge acquisition strategies in fuzzy rule based systems such as Pittsburgh and Michigan approaches in terms of convergence behaviour and accuracy. In this work, a generalization of this method is proposed to allow the simultaneous consideration of diversely configured knowledge bases and this way to accelerate the learning process of the original algorithm. In order to test the suggested strategy, a problem of practical importance nowadays, the design of expert meta-schedulers systems for grid computing is considered. Simulations results show the fact that the suggested adaptation improves the functionality of knowledge acquisition with a swarm intelligence approach and it reduces computational effort; at the same time it keeps the quality of the canonical strategy

    Specific Parameter-Free Global Optimization to Speed Up Setting and Avoid Factors Interactions

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    Meta-heuristics utilizing numerous parameters are more complicated than meta-heuristics with a couple of parameters for various reasons. In essence, the effort expected to tune the strategy-particular parameters is far more prominent as the quantity of parameters increases and furthermore, complex algorithms are liable for the presence of further parameter interactions. Jaya meta-heuristic does not involve any strategy-specific parameters and is a one-stage technique. It has demonstrated its effectiveness compared to major types of meta-heuristics and it introduces various points of interest, such as its easy deployment and set-up in industrial applications and its low complexity to be studied. In this work, a new meta-heuristic, Enhanced Jaya (EJaya) is proposed to overcome the inconsistency of Jaya in diverse situations, introducing coherent attraction and repulsion movements and restrained intensity for flight. Comparative results of EJaya in a set of benchmark problems including statistical tests show that it is feasible to increase the accuracy, scalability and exploitation capability of Jaya while keeping its specific parameter-free feature. EJaya is especially suitable for a priori undefined characteristics optimization functions or applications where the set-up time of the optimization process is critical and parameters tuning and interactions must be avoided

    The yeast prefoldin-like URI-orthologue Bud27 associates with the RSC nucleosome remodeler and modulates transcription

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    Bud27, the yeast orthologue of human URI/RMP, is a member of the prefoldin-like family of ATPindependent molecular chaperones. It has recently been shown to mediate the assembly of the three RNA polymerases in an Rpb5-dependent manner. In this work, we present evidence of Bud27 modulating RNA pol II transcription elongation. We show that Bud27 associates with RNA pol II phosphorylated forms (CTD-Ser5P and CTD-Ser2P), and that its absence affects RNA pol II occupancy of transcribed genes. We also reveal that Bud27 associatesin vivo with the Sth1 component of the chromatin remodeling complex RSC and mediates its association with RNA pol II. Our data suggest that Bud27, in addition of contributing to Rpb5 folding within the RNA polymerases, also participates in the correct assembly of other chromatin-associated protein complexes, such as RSC, thereby modulating their activit

    Evaluación de una estrategia para el control de la tuberculosis en un distrito sanitario de Andalucia

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    Fundamento: La tuberculosis en España y Andalucía presenta tasas de incidencia por encima de las de países de nuestro entorno. Muchos autores señalan la necesidad de mejorar la información epidemiológica, la organización de los servicios sanitarios y el apoyo social a los pacientes. El objetivo de este trabajo es evaluar los resultados de una estrategia que contemplaba los tres elementos reseñados en un Distrito de Atención Primaria de Andalucía. Métodos: Se realizó el seguimiento a 234 enfermos de tuberculosis residentes en el Distrito y notificados al Sistema de Vigilancia Epidemiológica de Andalucía durante el período 2004-2008. Se consideraron como indicadores de evaluación el porcentaje que finalizó el tratamiento, el porcentaje de pacientes bacilíferos con estudio de contactos, los nuevos casos detectados en los mismos y la incidencia en menores de 15 años. Resultados:.De los 234 pacientes incluidos se realizó un seguimiento efectivo en el 95%, de ellos finalizaron el tratamiento 182 (78%), fallecieron 18, se trasladaron de domicilio 10 y continuaban aún en tratamiento12. De los 130 casos que presentaron baciloscopia positiva se estudiaron a los contactos de 112 (el 86%). Se detectaron 27 nuevos casos entre los contactos estudiados y la incidencia anual en menores de 15 años fue del 6.65 por 100.000. Las perdidas del seguimiento se redujeron un 30% y las finalizaciones del tratamiento y los estudios de contactos mejoraron un 25% y 30% respectivamente, respecto a los datos del conjunto de Andalucía. Conclusiones: La estrategia seguida ha permitido mejorar los indicadores de evaluación propuestos. El % de casos nuevos detectados en los estudios de contactos y la incidencia anual en menores de 15 años ha sido similar en este estudio que en Andalucía

    Computer-Aided Laser-Fiber Output Beam 3D Spatial and Angular Design

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    Multiple laser beams and single-mode optical fibers output can be approximated by assuming that the emitted light has a symmetrical Gaussian intensity profile, which corresponds to the transverse electromagnetic mode (TEM00), which is designated as a Gaussian beam. Current free-accessible design tools are limited to the spatial analysis of the beams, in general, and to the intensity, in particular, and to the graphical visualization in 2D with very limited options. In this work, a novel a computer-aided laser-fiber output beam TEM00 designer, CATEM00, is presented based on the 3D representations typically provided by camera beam profilers, and on the fundamentals of the wave theory of light, including diverse flexibility capabilities for graphical manipulation and parameter comprehension both in terms of spatial behavior and in angular confinement. It must be highlighted that not only is the spatial limitation design of light impact relevant in TEM00 applications but, also, the angle with which the light reaches the target. Hence, the availability of capabilities of phase design in TEM00 following the paraxial limitations is highly convenient. Results and discussion in terms of intensity, power, divergence and wave fronts are presented considering a set of study cases, showing its coherence with Gaussian beam theory

    Dynamic Voltage Frequency Scaling Simulator for Real Workflows Energy-Aware Management in Green Cloud Computing

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    <div><p>Nowadays, the growing computational capabilities of Cloud systems rely on the reduction of the consumed power of their data centers to make them sustainable and economically profitable. The efficient management of computing resources is at the heart of any energy-aware data center and of special relevance is the adaptation of its performance to workload. Intensive computing applications in diverse areas of science generate complex workload called workflows, whose successful management in terms of energy saving is still at its beginning. WorkflowSim is currently one of the most advanced simulators for research on workflows processing, offering advanced features such as task clustering and failure policies. In this work, an expected power-aware extension of WorkflowSim is presented. This new tool integrates a power model based on a computing-plus-communication design to allow the optimization of new management strategies in energy saving considering computing, reconfiguration and networks costs as well as quality of service, and it incorporates the preeminent strategy for on host energy saving: Dynamic Voltage Frequency Scaling (DVFS). The simulator is designed to be consistent in different real scenarios and to include a wide repertory of DVFS governors. Results showing the validity of the simulator in terms of resources utilization, frequency and voltage scaling, power, energy and time saving are presented. Also, results achieved by the intra-host DVFS strategy with different governors are compared to those of the data center using a recent and successful DVFS-based inter-host scheduling strategy as overlapped mechanism to the DVFS intra-host technique.</p></div
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