109 research outputs found

    Construyendo Perfiles Virtuales Mediante el Procesamiento de Eventos Complejos

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    A medida que se incrementa el nímero de dispositivos inteligentes, el esfuerzo requerido para adaptarlos a las necesidades de cada usuario también crece. Asimismo, el proceso de adaptación de un dispositivo al contexto de un usuario es todavía un proceso muy manual. A pesar de que en los últimos años han surgido algunas propuestas centradas en obtener la información contextual de los usuarios para crear sus perfiles virtuales, se necesitan soluciones novedosas que permitan crear perfiles más completos, que sean utilizados por los dispositivos inteligentes para adaptarse automáticamente a las necesidades de sus usuarios, redundando en una mayor exactitud de la adaptación. En este artículo se propone la integración del modelo computacional People as a Service (PeaaS) con el procesamiento de eventos complejos (CEP) para la creación en tiempo real de perfiles virtuales complejos desde el propio dispositivo móvil y la compartición de estos como servicios para el resto de sistemas y dispositivos. Además, se evalúa esta integración en un caso de estudio sobre Alzheimer. Los resultados confirman que el uso de la tecnología CEP para la identificación de información contextual compleja es posible.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Thermal, dielectrical and mechanical response of α and β-poly(vinilydene fluoride)/Co-MgO nanocomposites

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    Nanocomposites of the self-forming core-shell Co-MgO nanoparticles, which were of approximately 100 nm in diameter, and poly(vinylidene fluoride) (PVDF) polymer have been prepared. When the polymer is crystallized in the α-phase, the introduction of the nanoparticles leads to nucleation of the γ-phase of PVDF, increasing also the melting temperature of the polymer. With the introduction of the Co-MgO particles, the dielectric constant of the material slightly increases and the storage modulus decreases with respect to the values obtained for the pure polymer

    Conditions determining the morphology and nanoscale magnetism of Co nanoparticles: Experimental and numerical studies

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    Co-based nanostructures ranging from core-shell to hollow nanoparticles were produced by varying the reaction time and the chemical environment during the thermal decomposition of Co2(CO)8. Both structural characterization and kinetic model simulation illustrate that the diffusivities of Co and oxygen determine the growth ratio and the final morphology of the nanoparticles. Exchange coupling between Co and Co-oxide in core/shell nanoparticles induced a shift of field-cooled hysteresis loops that is proportional to the shell thickness, as verified by numerical studies. The increased nanocomplexity when going from core/shell to hollow particles, also leads to the appearance of hysteresis above 300 K due to an enhancement of the surface anisotropy resulting from the additional spin-disordered surfaces.Comment: 29 pages including 11 figures embedded. Submitted to Phys. Rev.

    Paving the Way for a Real-Time Context-Aware Predictive Architecture

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    Internet of Things society generates and needs to consume huge amounts of data in a demanding context-aware scenario. Such exponentially growing data sources require the use of novel processing methodologies, technologies and tools to facilitate data processing in order to detect and prevent situations of interest for the users in their particular context. To solve this issue, we propose an architecture which making use of emerging technologies and cloud platforms can process huge amounts of heterogeneous data and promptly alert users of relevant situations for a particular domain according to their context. Last, but not least, we will provide a graphical tool for domain experts to easily model, automatically generate code and deploy the situations to be detected and the actions to be taken in consequence. The proposal will be evaluated through a real case study related to air quality monitoring and lung diseases in collaboration with a doctor specialist on lung diseases of a public hospital

    Problems of female migration in Spain: areas of action and proposals for improvement

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    El presente trabajo pretende establecer una serie de propuestas de mejora en una serie de ámbitos concretos de actuación con el colectivo migrante y, más concretamente, con las mujeres que llegan a nuestro país. Para ello, nos acercamos a una serie de datos estadísticos que nos permiten establecer el perfil de la mujer migrante en España para, a continuación, realizar estas propuestas para este colectivo específico, atendiendo a una serie de ámbitos de actuación —establecidos allá por el año 2007, momento en el que se publica el primer plan estratégico de ciudadanía e integración en España— y que aún siguen rigiendo las políticas públicas migratorias y las propuestas internacionales en materia de mujer e inmigraciónThis paper aims to establish a series of proposals for improvement in several specific action areas with the migrant group and, more specifically, with the women who arrive in our country. To do this, we approach a series of statistical data that allow us to establish the profile of migrant women in Spain, to then make these proposals for this specific group, considering a series of areas of action — established in 2007, when the first strategic plan for citizenship and integration was published in Spain— which still govern public migration policies, and the international proposals on women and immigrationS

    Controlling Magnetization Reversal and Hyperthermia Efficiency in Core-Shell Iron-Iron Oxide Magnetic Nanoparticles by Tuning the Interphase Coupling

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    Magnetic particle hyperthermia, in which colloidal nanostructures are exposed to an alternating magnetic field, is a promising approach to cancer therapy. Unfortunately, the clinical efficacy of hyperthermia has not yet been optimized. Consequently, routes to improve magnetic particle hyperthermia, such as designing hybrid structures comprised of different phase materials, are actively pursued. Here, we demonstrate enhanced hyperthermia efficiency in relatively large spherical Fe/Fe-oxide core-shell nanoparticles through the manipulation of interactions between the core and shell phases. Experimental results on representative samples with diameters in the range 30-80 nm indicate a direct correlation of hysteresis losses to the observed heating with a maximum efficiency of around 0.9 kW/g. The absolute particle size, the core-shell ratio, and the interposition of a thin wüstite interlayer are shown to have powerful effects on the specific absorption rate. By comparing our measurements to micromagnetic calculations, we have unveiled the occurrence of topologically nontrivial magnetization reversal modes under which interparticle interactions become negligible, aggregates formation is minimized and the energy that is converted into heat is increased. This information has been overlooked until date and is in stark contrast to the existing knowledge on homogeneous particles

    Learning form Nature to improve the heat generation of iron-oxide nanoparticles for magnetic hyperthermia applications.

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    The performance of magnetic nanoparticles is intimately entwined with their structure, mean size and magnetic anisotropy. Besides, ensembles offer a unique way of engineering the magnetic response by modifying the strength of the dipolar interactions between particles. Here we report on an experimental and theoretical analysis of magnetic hyperthermia, a rapidly developing technique in medical research and oncology. Experimentally, we demonstrate that single-domain cubic iron oxide particles resembling bacterial magnetosomes have superior magnetic heating efficiency compared to spherical particles of similar sizes. Monte Carlo simulations at the atomic level corroborate the larger anisotropy of the cubic particles in comparison with the spherical ones, thus evidencing the beneficial role of surface anisotropy in the improved heating power. Moreover we establish a quantitative link between the particle assembling, the interactions and the heating properties. This knowledge opens new perspectives for improved hyperthermia, an alternative to conventional cancer therapies

    Particle interactions in liquid magnetic colloids by zero field cooled measurements: effects on heating efficiency

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    The influence of magnetic interactions in assemblies formed by either aggregated or disaggregated uniform gamma-Fe_2O_3 particles are investigated as a function of particle size, concentration, and applied field. Hyperthermia and magnetization measurements are performed in the liquid phase of colloids consisting of 8 and 13 nm uniform gamma-Fe_2O_3 particles dispersed in water and hexane. Although hexane allows the disagglomerated obtaining particle system; aggregation is observed in the case of water colloids. The zero field cooled (ZFC) curves show a discontinuity in the magnetization values associated with the melting points of water and hexane. Additionally, for 13 nm gamma-Fe_2O_3 dispersed in hexane, a second magnetization jump is observed that depends on particle concentration and shifts toward lower temperature by increasing applied field. This second jump is related to the strength of the magnetic interactions as it is only present in disagglomerated particle systems with the largest size, i.e., is not observed for 8 nm superparamagnetic particles, and surface effects can be discarded. The specific absorption rate (SAR) decreases with increasing concentration only for the hexane colloid, whereas for aqueous colloids, the SAR is almost independent of particle concentration. Our results suggest that, as a consequence of the magnetic interactions, the dipolar field acting on large particles increases with concentration, leading to a decrease of the SAR
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