6,792 research outputs found
FARC Terrorism in Colombia: A Clustering Analysis
This paper applies clustering analysis to the Colombian armed conflict. Indeed, when applied to a FARC terrorist act database, this statistical procedure finds a natural clustering of the diferent FARC units according to the diferent types of terrorist acts they commit and identities the military hard core of the FARC. The facts revealed in this paper should be useful not only for future military strategies, but also to determine a better priorization and geographical allocation of the scarce military resources.Clustering Analysis,
Flux-cutting and flux-transport effects in type-II superconductor slabs in a parallel rotating magnetic field
The magnetic response of irreversible type-II superconductor slabs subjected
to in-plane rotating magnetic field is investigated by applying the circular,
elliptic, extended-elliptic, and rectangular flux-line-cutting critical-state
models. Specifically, the models have been applied to explain experiments on a
PbBi rotating disk in a fixed magnetic field , parallel to the flat
surfaces. Here, we have exploited the equivalency of the experimental situation
with that of a fixed disk under the action of a parallel magnetic field,
rotating in the opposite sense. The effect of both the magnitude of the
applied magnetic field and its angle of rotation upon the
magnetization of the superconductor sample is analyzed. When is smaller
than the penetration field , the magnetization components, parallel and
perpendicular to , oscillate with increasing the rotation angle. On
the other hand, if the magnitude of the applied field, , is larger than
, both magnetization components become constant functions of at
large rotation angles. The evolution of the magnetic induction profiles inside
the superconductor is also studied.Comment: 12 pages, 29 figure
Infrared excesses in stars with and without planets using revised photometry
We present an analysis on the potential prevalence of mid infrared excesses
in stars with and without planetary companions. Based on an extended database
of stars detected with the satellite, we studied two stellar
samples: one with 236 planet hosts and another with 986 objects for which
planets have been searched but not found. We determined the presence of an
excess over the photosphere by comparing the observed flux ratio at 22 m
and 12 m () with the corresponding synthetic value, derived
from results of classical model photospheres. We found a detection rate of
0.85 at 22 m (2 excesses) in the sample of stars with planets and
0.1 (1 detection) for the stars without planets. The difference of the
detection rate between the two samples is not statistically significant, a
result that is independent of the different approaches found in the literature
to define an excess in the wavelength range covered by
observations. As an additional result, we found that the fluxes
required a normalisation procedure to make them compatible with synthetic data,
probably pointing out a revision of the data calibration.Comment: 10 pages, 6 figures, 3 tables. Accepted for publication in MNRA
Low level of virological failure and drug resistance among patients receiving antiretroviral treatment under programme conditions in Maputo, Mozambique
Mexico AIDS Conference 200
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