6,749 research outputs found

    Imperfect bifurcations via topological methods in superlinear indefinite problems

    Full text link
    In [5] the structure of the bifurcation diagrams of a class of superlinear indefinite problems with a symmetric weight was ascertained, showing that they consist of a primary branch and secondary loops bifurcating from it. In [4] it has been proved that, when the weight is asymmetric, the bifurcation diagrams are no longer connected since parts of the primary branch and loops of the symmetric case form an arbitrarily high number of isolas. In this work we give a deeper insight on this phenomenon, studying how the secondary bifurcations break as the weight is perturbed from the symmetric situation. Our proofs rely on the approach of [5,4], i.e. on the construction of certain Poincar\'e maps and the study of how they vary as some of the parameters of the problems change, constructing in this way the bifurcation diagrams.Comment: 13 pages, 7 figure

    An approach to emotion recognition in single-channel EEG signals: a mother child interaction

    Get PDF
    In this work, we perform a first approach to emotion recognition from EEG single channel signals extracted in four (4) mother-child dyads experiment in developmental psychology -- Single channel EEG signals are analyzed and processed using several window sizes by performing a statistical analysis over features in the time and frequency domains -- Finally, a neural network obtained an average accuracy rate of 99% of classification in two emotional states such as happiness and sadness20th Argentinean Bioengineering Society Congress, SABI 2015 (XX Congreso Argentino de Bioingeniería y IX Jornadas de Ingeniería Clínica)28–30 October 2015, San Nicolás de los Arroyos, Argentin

    ProBiota: Programa para el estudio y uso sustentable de la biota austral. Documentación y Actividades.

    Get PDF

    Deterministic Routing with HoL-Blocking-Awareness for Direct Topologies

    Get PDF
    AbstractRouting is a key design factor to obtain the maximum performance out of interconnection networks. Depending on the number of routing options that packets may use, routing algorithms are classified into two categories. If the packet can only use a single predetermined path, routing is deterministic, whereas if several paths are available, it is adaptive. It is well-known that adaptive routing usually outperforms deterministic routing. However, adaptive routers are more complex and introduces out-of-order delivery of packets. In this paper, we take up the challenge of developing a deterministic routing algorithm for direct topologies that can obtain a similar performance than adaptive routing, while providing the inherent advantages of deterministic routing such as in-order delivery of packets and implementation simplicity. The proposed deterministic routing algorithm is aware of the HoL-blocking effect, and it is designed to reduce it, which, as known, it is a key contributor to degrade interconnection network performance

    Formation of X-ray emitting stationary shocks in magnetized protostellar jets

    Get PDF
    X-ray observations of protostellar jets show evidence of strong shocks heating the plasma up to temperatures of a few million degrees. In some cases, the shocked features appear to be stationary. They are interpreted as shock diamonds. We aim at investigating the physics that guides the formation of X-ray emitting stationary shocks in protostellar jets, the role of the magnetic field in determining the location, stability, and detectability in X-rays of these shocks, and the physical properties of the shocked plasma. We performed a set of 2.5-dimensional magnetohydrodynamic numerical simulations modelling supersonic jets ramming into a magnetized medium and explored different configurations of the magnetic field. The model takes into account the most relevant physical effects, namely thermal conduction and radiative losses. We compared the model results with observations, via the emission measure and the X-ray luminosity synthesized from the simulations. Our model explains the formation of X-ray emitting stationary shocks in a natural way. The magnetic field collimates the plasma at the base of the jet and forms there a magnetic nozzle. After an initial transient, the nozzle leads to the formation of a shock diamond at its exit which is stationary over the time covered by the simulations (~ 40 - 60 yr; comparable with time scales of the observations). The shock generates a point-like X-ray source located close to the base of the jet with luminosity comparable with that inferred from X-ray observations of protostellar jets. For the range of parameters explored, the evolution of the post-shock plasma is dominated by the radiative cooling, whereas the thermal conduction slightly affects the structure of the shock.Comment: Accepted for publication in Astronomy and Astrophysic

    The Sustainable Management of Metals: An Analysis of Global Research

    Get PDF
    The objective of this study was to analyze research trends in the field of sustainable management of metals on a global level between 1993 and 2017. To do so, a bibliometric analysis was carried out on a total of 6967 articles. The results revealed the growing interest in this research field, particularly over the last five year-period during which 63% of all articles were published. The three journals in which most articles had been published were the Journal of Cleaner Production, ACS Sustainable Chemistry and Engineering, and Chemsuschem. The countries that published the most articles were China, the United States, India, Germany, and the United Kingdom. A sizeable network of collaboration has been established between countries for the joint publication of studies. The main lines of research have been focused on metal decontamination in water and soil, waste management oriented towards reuse and recycling, and the innovation of processes for cleaner and more efficient production. The results revealed the need for comprehensive studies that integrate different disciplines within the same analytical framework, and to promote research that contributes to the different dimensions of sustainability (environmental, economic, and social)

    Influencia de la relación tensión-deslizamiento en el comportamiento de la interfase FRP-Hormigón

    Get PDF
    En el presente trabajo se han analizado los modelos tensión-deslizamiento más divulgados para estudiar las tensiones en la interfase FRP-Hormigón y la carga máxima mediante su irapíementación en una de las principales técnicas de cálculo numérico fácilmente programable y aplicable para el caso en el que se tiene tracción en ambos extremos de la banda FRP. Los resultados se comparan con las soluciones analíticas encontradas en la literatura, las cuales están limitadas a los casos de una función tensión-deslizamiento lineal y bilineal. Finalmente, se contrasta la teoría con los resultados experimentales obtenidos de ensayos de tipología análoga al método beamtest empleado comúnmente para medir la adherencia de barras de acero
    corecore