341 research outputs found
Recomendaciones generales para la mejora del diseño y construcción de edificios (1ª parte)
Recomendaciones generales para la mejora del diseño y construcción de edificios (3ª y última parte)
Aspectos de planificación e instalación en las redes urbanas de transmisión de señales audiovisuales por cable
Wavelet Based Fractal Analysis of Airborne Pollen
The most abundant biological particles in the atmosphere are pollen grains
and spores. Self protection of pollen allergy is possible through the
information of future pollen contents in the air. In spite of the importance of
airborne pol len concentration forecasting, it has not been possible to predict
the pollen concentrations with great accuracy, and about 25% of the daily
pollen forecasts have resulted in failures. Previous analysis of the dynamic
characteristics of atmospheric pollen time series indicate that the system can
be described by a low dimensional chaotic map. We apply the wavelet transform
to study the multifractal characteristics of an a irborne pollen time series.
We find the persistence behaviour associated to low pollen concentration values
and to the most rare events of highest pollen co ncentration values. The
information and the correlation dimensions correspond to a chaotic system
showing loss of information with time evolution.Comment: 11 pages, 7 figure
Análisis cuantitativo de estilos de aprendizaje y satisfacción en contextos de aprendizaje basado en proyectos de accesibilidad
Este trabajo se centra en el análisis cuantitativo mediante técnicas estadÃsticas de
clasificación al problema del estudio de los estilos de aprendizaje (superficial, profundo) y la
satisfacción de los estudiantes en el marco de asignaturas universitarias centradas en el aprendizaje
de la accesibilidad y gestión de proyectos académicos. Los principales resultados hacen hincapié en
la predominancia del estilo profundo respecto al superficial y en la significancia estadÃstica entre
estilos de aprendizaje y satisfacción.Postprint (published version
Trapping mechanism in overdamped ratchets with quenched noise
A trapping mechanism is observed and proposed as the origin of the anomalous
behavior recently discovered in transport properties of overdamped ratchets
subject to external oscillatory drive in the presence of quenched noise. In
particular, this mechanism is shown to appear whenever the quenched disorder
strength is greater than a threshold value. The minimum disorder strength
required for the existence of traps is determined by studying the trap
structure in a disorder configuration space. An approximation to the trapping
probability density function in a disordered region of finite length included
in an otherwise perfect ratchet lattice is obtained. The mean velocity of the
particles and the diffusion coefficient are found to have a non-monotonic
dependence on the quenched noise strength due to the presence of the traps.Comment: 21 pages, 6 figures, to appear in PR
Sphere rolling on the surface of a cone
We analyse the motion of a sphere that rolls without slipping on a conical
surface having its axis in the direction of the constant gravitational field of
the Earth. This nonholonomic system admits a solution in terms of quadratures.
We exhibit that the only circular of the system orbit is stable and furthermore
show that all its solutions can be found using an analogy with central force
problems. We also discuss the case of motion with no gravitational field, that
is, of motion on a freely falling cone.Comment: 12 pages, 2 figures, to be published in Eur J Phy
Phenomenological aspects of the fermion and scalar sectors of a flavored 3-3-1 model
We propose a viable and predictive model based on the gauge symmetry, supplemented by the global symmetry,
the family symmetry and several auxiliary cyclic symmetries, which
successfully reproduces the observed SM fermion mass and mixing pattern. The SM
charged fermion mass and quark mixing hierarchy is caused by the spontaneous
breaking of the discrete symmetries, whereas the tiny active neutrino masses
are generated through an inverse seesaw mechanism mediated by right-handed
Majorana neutrinos. The model is consistent with the SM fermion masses and
mixings and successfully accommodates the current Higgs diphoton decay rate
constraints as well as the constraints arising from oblique , and
parameters and meson oscillations.Comment: 23 pages, 7 figure
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