5,854 research outputs found
Biomechanical analysis of a cranial Patient Specific Implant on the interface with the bone using the Finite Element Method
- New advance technologies based on reverse engineering , design and additive
manufacturing, have expanded design capabilities for biomedical applications to
include Patient Specific Implants (PSI). This change in design paradigms needs
advanced tools to assess the mechanical performance of the product, and
simulate the impact on the patient. In this work, we perform a structural
analysis on the interface of a cranial PSI under static loading conditions.
Based on those simulations, we have identified the regions with high stress and
strain and checked the failure criteria both in the implant and the skull. We
evaluate the quality of the design of the implant and determine their response
given different materials, in order to ensure optimality of the final product
to be manufactured
Tensorial perturbations in the bulk of inflating brane worlds
In this paper we consider the stability of some inflating brane-world models
in quantum cosmology. It is shown that whereas the singular model based on the
construction of inflating branes from Euclidean five-dimensional anti-de Sitter
space is unstable to tensorial cosmological perturbations in the bulk, the
nonsingular model which uses a five-dimensional asymptotically anti-de Sitter
wormhole to construct the inflating branes is stable to these perturbations.Comment: 4 pages, RevTex, to appear in Phys. Rev.
Spectropolarimetric analysis of an active region filament. I. Magnetic and dynamical properties from single component inversions
The determination of the magnetic filed vector in solar filaments is possible
by interpreting the Hanle and Zeeman effects in suitable chromospheric spectral
lines like those of the He I multiplet at 10830 A. We study the vector magnetic
field of an active region filament (NOAA 12087). Spectropolarimetric data of
this active region was acquired with the GRIS instrument at the GREGOR
telescope and studied simultaneously in the chromosphere with the He I 10830 A
multiplet and in the photosphere with the Si I 10827 A line. As it is usual
from previous studies, only a single component model is used to infer the
magnetic properties of the filament. The results are put into a solar context
with the help of the Solar Dynamic Observatory images. Some results clearly
point out that a more complex inversion had to be done. Firstly, the Stokes
map of He I does not show any clear signature of the presence of the filament.
Secondly, the local azimuth map follows the same pattern than Stokes as if
the polarity of Stokes were conditioning the inference to very different
magnetic field even with similar linear polarization signals. This indication
suggests that the Stokes could be dominated by the below magnetic field
coming from the active region, and not, from the filament itself. Those and
more evidences will be analyzed in depth and a more complex inversion will be
attempted in the second part of this series.Comment: 18 pages, 19 figures, accepted for publication in A&
Anti-de Sitter wormhole kink
The metric describing a given finite sector of a four-dimensional
asymptotically anti-de Sitter wormhole can be transformed into the metric of
the time constant sections of a Tangherlini black hole in a five-dimensional
anti-de Sitter spacetime when one allows light cones to tip over on the
hypersurfaces according to the conservation laws of an one-kink. The resulting
kinked metric can be maximally extended, giving then rise to an instantonic
structure on the euclidean continuation of both the Tangherlini time and the
radial coordinate. In the semiclassical regime, this kink is related to the
existence of closed timelike curves.Comment: 10 pages, to appear in IJMP
Análisis de la organización funcional en el fútbol
De manera tradicional, el estudio de la estrategia motriz (táctica) en el fútbol se ha venido realizando tomando como referencia de partida, la distribución espacial de los jugadores al inicio de cada parte de los encuentros y las denominadas "jugadas estratégicas" o "jugadas a balón parado". Este trabajo es una investigación sobre la estrategia motriz en el fútbol, la cual tiene como referente teórico a la Praxiología motriz. Sus objetivos son el estudio de la estrategia motriz (táctica), específicamente la organización funcional: usos de los subroles estratégico motores, de los equipos, en tanto que interacción motriz; considerando también las acciones con balón y su gestió
- …