366 research outputs found
Inferring dynamic genetic networks with low order independencies
In this paper, we propose a novel inference method for dynamic genetic
networks which makes it possible to face with a number of time measurements n
much smaller than the number of genes p. The approach is based on the concept
of low order conditional dependence graph that we extend here in the case of
Dynamic Bayesian Networks. Most of our results are based on the theory of
graphical models associated with the Directed Acyclic Graphs (DAGs). In this
way, we define a minimal DAG G which describes exactly the full order
conditional dependencies given the past of the process. Then, to face with the
large p and small n estimation case, we propose to approximate DAG G by
considering low order conditional independencies. We introduce partial qth
order conditional dependence DAGs G(q) and analyze their probabilistic
properties. In general, DAGs G(q) differ from DAG G but still reflect relevant
dependence facts for sparse networks such as genetic networks. By using this
approximation, we set out a non-bayesian inference method and demonstrate the
effectiveness of this approach on both simulated and real data analysis. The
inference procedure is implemented in the R package 'G1DBN' freely available
from the CRAN archive
Proyecto de ordenación paisajista del Recinto 1 del Conjunto Arqueológico Dólmenes de Antequera
El Sitio de los Dólmenes de Antequera es Patrimonio Mundial desde Julio 2016. La incorporación en la lista
del Patrimonio de la Humanidad conlleva una serie de compromisos con ICOMOS para el correcto
tratamiento del Sitio inscrito y para mejorar sus relaciones, con el entorno próximo y lejano tanto a nivel
urbanístico como paisajístico.
El proyecto de restauración paisajística forma parte de dichas medidas previstas para resolver el
tratamiento paisajístico del Recinto 1 así como los problemas de circulación ligados a la visita pública. La
propuesta pretende resolver la ordenación paisajística del Recinto 1 del Conjunto Arqueológico Dólmenes
de Antequera con el mayor respeto posible de los yacimientos existentes.
La propuesta paisajística desarrolla actuaciones concretas sobre arbolado y vegetación, trazado y
acondicionamiento de caminos, mobiliario urbano, iluminación, aprovechamiento de los recursos hídricos,
etc. para conseguir una correcta integración y un tratamiento adecuado del ámbito.
En estrecha colaboración con la Agencia de Medio Ambiente y Agua de Andalucía, se ha elaborado una
selección minuciosa de plantas autóctonas de la flora silvestre andaluza, adaptadas al medio del proyecto y
que hacen referencia a los tiempos prehistóricos de los Dólmenes, ya que corresponden a la evolución
natural del paisaje si no hubiera habido actuaciones humanas sobre este territorio.
Además de la utilización de especies nativas, se plantea la incorporación de algunas especies amenazadas
o en peligro de extinción. En efecto, se pretende utilizar el proyecto como plataforma para la conservación
de la flora amenazada a través de su incorporación en un parque público.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Integrating industrial ecology thinking into the management of mining waste
Mining legacies are often dominated by large waste facilities and their associated environmental impacts. The most serious environmental problem associated with mine waste is heavy metals and acid leakage through a phenomenon called acid mine drainage (AMD). Interestingly, the toxicity of this leakage is partly due to the presence of valuable metals in the waste stream as a result of a diversity of factors influencing mining operations. A more preventive and recovery-oriented approach to waste management, integrated into mine planning and operations, could be both economically attractive and environmentally beneficial since it would: mitigate environmental impacts related to mine waste disposal (and consequently reduce the remediation costs); and increase the resource recovery at the mine site level. The authors argue that eco-efficiency and resilience (and the resulting increase in a mine’s lifetime) are both critical—yet overlooked—characteristics of sustainable mining operations. Based on these arguments, this paper proposes a framework to assist with identification of opportunities for improvement and to measure this improvement in terms of its contribution to a mine’s sustainability performance
IT diffusion in the Brazilian public sector: organizational culture versus efficiency
Unavailable.Indisponível
VANET Applications: Hot Use Cases
Current challenges of car manufacturers are to make roads safe, to achieve
free flowing traffic with few congestions, and to reduce pollution by an
effective fuel use. To reach these goals, many improvements are performed
in-car, but more and more approaches rely on connected cars with communication
capabilities between cars, with an infrastructure, or with IoT devices.
Monitoring and coordinating vehicles allow then to compute intelligent ways of
transportation. Connected cars have introduced a new way of thinking cars - not
only as a mean for a driver to go from A to B, but as smart cars - a user
extension like the smartphone today. In this report, we introduce concepts and
specific vocabulary in order to classify current innovations or ideas on the
emerging topic of smart car. We present a graphical categorization showing this
evolution in function of the societal evolution. Different perspectives are
adopted: a vehicle-centric view, a vehicle-network view, and a user-centric
view; described by simple and complex use-cases and illustrated by a list of
emerging and current projects from the academic and industrial worlds. We
identified an empty space in innovation between the user and his car:
paradoxically even if they are both in interaction, they are separated through
different application uses. Future challenge is to interlace social concerns of
the user within an intelligent and efficient driving
Monarchie et patriciats municipaux en Castille sous Charles II. Le renouvellement des millions à la fin du XVIIe siècle
Ecrit en 2000, révisé en 2003. Devait être publié dans un ouvrage collectif resté en souffrance...At the end of the XVIIth century, every six years, every Castilian town with a right to send members to the Cortes, had to renew its consent to the "millones" tax. This being done, the members of the town councils begged for favors from the royal gratitude. Their petitions and related papers have been preserved. They provide a crude but higly interesting point of view over the system of personal relationships between the king and the town fathers which developped at that time. Recent historiography considers these developments as of utmost importance to explain the raise of absolutism.Le renouvellement tous les six ans de l'impôt des millions par les municipalités ayant droit de vote aux Cortes est l'occasion pour les membres des corps municipaux concernés de demander au roi faveurs et récompenses. Leurs pétitions, les réponses données et les documents de négociations sont soigneusement archivés. Cette source permet une plongée dans l'univers de la relation personnelle développée par le souverain avec chacun des membres de l'élite municipale, dans laquelle l'historiographie actuelle voit l'un des outils principaux du développement de l'Etat absolu
An EM algorithm for estimation in the Mixture Transition Distribution model
The Mixture Transition Distribution (MTD) model was introduced by Raftery to
face the need for parsimony in the modeling of high-order Markov chains in
discrete time. The particularity of this model comes from the fact that the
effect of each lag upon the present is considered separately and additively, so
that the number of parameters required is drastically reduced. However, the
efficiency for the MTD parameter estimations proposed up to date still remains
problematic on account of the large number of constraints on the parameters. In
this paper, an iterative procedure, commonly known as Expectation-Maximization
(EM) algorithm, is developed cooperating with the principle of Maximum
Likelihood Estimation (MLE) to estimate the MTD parameters. Some applications
of modeling MTD show the proposed EM algorithm is easier to be used than the
algorithm developed by Berchtold. Moreover, the EM Estimations of parameters
for high-order MTD models led on DNA sequences outperform the corresponding
fully parametrized Markov chain in terms of Bayesian Information Criterion. A
software implementation of our algorithm is available in the library seq++ at
http://stat.genopole.cnrs.fr/seqppComment: 22 page
The structure of radiative shock waves. V. Hydrogen emission lines
We considered the structure of steady-state plane-parallel radiative shock
waves propagating through the partially ionized hydrogen gas of temperature T_1
= 3000K and density 1e-12 gm/cm^3 <= \rho_1 <= 1e-9 gm/cm^3. The upstream Mach
numbers range within 6 <= M_1 <= 14. In frequency intervals of hydrogen lines
the radiation field was treated using the transfer equation in the frame of the
observer for the moving medium, whereas the continuum radiation was calculated
for the static medium. Doppler shifts in Balmer emission lines of the radiation
flux emerging from the upstream boundary of the shock wave model were found to
be roughly one-third of the shock wave velocity. The gas emitting the Balmer
line radiation is located at the rear of the shock wave in the hydrogen
recombination zone where the gas flow velocity in the frame of the observer is
approximately one-half of the shock wave velocity. The ratio of the Doppler
shift to the gas flow velocity of 0.7 results both from the small optical
thickness of the shock wave in line frequencies and the anisotropy of the
radiation field typical for the slab geometry. In the ambient gas with density
of \rho_1 >= 1e-11 gm/cm^3 the flux in the H-alpha frequency interval reveals
the double structure of the profile. A weaker H-beta profile doubling was found
for \rho_1 >= 1e-10 gm/cm^3 and U_1 <= 50 km/s. The unshifted redward component
of the double profile is due to photodeexcitation accompanying the rapid growth
of collisional ionization in the narrow layer in front of the discontinuous
jump.Comment: 13 pages, 13 figures, LaTeX, accepted for publication in A
Search for surface magnetic fields in Mira stars. First detection in chi Cyg
In order to complete the knowledge of the magnetic field and of its influence
during the transition from Asymptotic Giant Branch to Planetary Nebulae stages,
we have undertaken a search for magnetic fields at the surface of Mira stars.
We used spectropolarimetric observations, collected with the Narval instrument
at TBL, in order to detect - with Least Squares Deconvolution method - a Zeeman
signature in the visible part of the spectrum. We present the first
spectropolarimetric observations of the S-type Mira star chi Cyg, performed
around its maximum light. We have detected a polarimetric signal in the Stokes
V spectra and we have established its Zeeman origin. We claim that it is likely
to be related to a weak magnetic field present at the photospheric level and in
the lower part of the stellar atmosphere. We have estimated the strength of its
longitudinal component to about 2-3 Gauss. This result favors a 1/r law for the
variation of the magnetic field strength across the circumstellar envelope of
chi Cyg. This is the first detection of a weak magnetic field at the stellar
surface of a Mira star and we discuss its origin in the framework of shock
waves periodically propagating throughout the atmosphere of these radially
pulsating stars. At the date of our observations of chi Cyg, the shock wave
reaches its maximum intensity, and it is likely that the shock amplifies a weak
stellar magnetic field during its passage through the atmosphere. Without such
an amplification by the shock, the magnetic field strength would have been too
low to be detected. For the first time, we also report strong Stokes Q and U
signatures (linear polarization) centered onto the zero velocity (i.e., at the
shock front position). They seem to indicate that the radial direction would be
favored by the shock during its propagation throughout the atmosphere.Comment: 9 pages, 4 figures accepted by Astronomy and Astrophysics (21
November 2013
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