310 research outputs found
Procedimientos y acciones en materia de Protección de Datos. Especial referencia a las Agencias Autonómicas
Este texto se dedica a los procedimientos y acciones en materia de protección de datos, fundamentalmente las reclamaciones y denuncias. Partiendo de la labor de la Agencia Española de Protección de Datos, se centra en las Autoridades Autonómicas con mas experiencia (la de la Comunidad de Madrid) y en la más reciente (Cataluña) referentes para la nueva Agencia Vasca.Testu honek datuen babeserako prozedurak eta ekintzak azaltzen ditu, erreklamazioak eta salaketak oro har. Datuen Babeserako Espainiako Agentziaren lana abiapuntutzat hartuta, esperientzia gehien duten Autoritate Autonomikoak (Madrilgo Komunitatea) zein berriagoak diren horiek (Katalunia) aztertzen ditu Euskal Agentziari begira erreferente direlako.Ce texte aborde les procédures et actions en matière de protection des données et en particulier les réclamations et plaintes. Sur la base du travail réalisé par l'Agence Espagnole de Protection des données, il se centre sur les Autorités Autonomes à plus grande expérience en la matière (la Communauté de Madrid) et la plus récente (Catalogne), en tant que référents pour la nouvelle Agence Basque.This text covers the procedures and actions regarding data protection, essentially claims and formal complaints. Starting from the task of the Spanish Data Protection Agency, we focus on the Autonomous Authorities with the most experience (the Autonomous Community of Madrid) and the most recent (Catalonia) as references for the new Basque Agency
Advances in methods for determining fecundity: application of the new methods to some marine fishes
Estimation of individual egg production (realized fecundity)
is a key step either to understand the stock and recruit relationship or to carry out fisheries-independent
assessment of spawning stock biomass using egg production methods. Many fish are highly fecund and their ovaries may weigh over a kilogram; therefore the work time can be consuming and require large quantities of toxic fixative. Recently it has been shown for Atlantic cod (Gadus morhua) that image analysis can automate fecundity determination
using a power equation that links follicles per gram ovary to the mean vitellogenic follicular diameter (the autodiametric method).
In this article we demonstrate the precision of the autodiametric method applied to a range of species with different spawning strategies during maturation and spawning. A new method using a solid displacement pipette to remove quantitative fecundity samples (25, 50, 100, and 200 milligram [mg]) is evaluated, as are the underlying assumptions to effectively fix and subsample the ovary. Finally, we demonstrate the interpretation of dispersed formaldehyde-fixed ovarian samples (whole mounts) to assess the presence of atretic and postovulatory follicles to replace labor intensive histology. These results can be used to estimate down regulation (production of atretic follicles) of fecundity during maturation
Comparative demography and diversity of small mammals in precordilleran temperate rainforests of Southern Chile
Small mammals were studied in two southern Chilean temperate rainforests in the precordillean Andes during 2 low-rainfall years following the 1982 El Niño event. Forests had somewhat different levels of canopy, shrub, and herbaceous cover, and species richness of trees but most of the same plants. Most captures were of four sigmodontine rodents, Akodon olivaceus, Abrothrix longipilis, Abrothrix sanborni, and Oligoryzomys longicaudatus; five other species and a putative hybrid were recorded. Maximum numbers were in January-July (late summer to winter) and lower numbers in August-December (late winter to early summer). All species had seasonal reproduction in September-April (spring to autumn). A. olivaceus and A. longipilis generally were long-lived, whereas survival rates were low for O. longicaudatus. Responses after the 1982 El Niño were small, and some populations increased during 1984. Populations of A. olivaceus fluctuated more than those of A. longipilis; those of A. sanborni were low and O. longicaudatus was sporadic and irruptive. Lower-elevational Chilean and precordilleran Argentine forests have similar species composition, but differences in demography and dominance of the former by more widespread, omnivorous A. olivaceus, animalivorous-fungivorous Abrothrix, and granivorous O. longicaudatus. Opportunities for immigration may explain greater homogeneity of populations of small mammals in Chilean rainforests relative to Argentine ones. Although responses to El Niño and subsequent droughts were weak, flowering episodes of bamboo (Chusquea) can have strong effects due to increased availability of food
Applications of the unsteady vortex-lattice method in aircraft aeroelasticity and flight dynamics
The Unsteady Vortex-Lattice Method provides a medium-fidelity tool for the prediction of non-stationary aerodynamic loads in low-speed, but high-Reynolds-number, attached flow conditions. Despite a proven track record in applications where free-wake modelling is critical, other less computationally-expensive potential-flow models, such as the Doublet-Lattice Method and strip theory, have long been favoured in fixed-wing aircraft aeroelasticity and flight dynamics. This paper presents how the Unsteady Vortex-Lattice Method can be implemented as an enhanced alternative to those techniques for diverse situations that arise in flexible-aircraft dynamics. A historical review of the methodology is included, with latest developments and practical applications. Different formulations of the aerodynamic equations are outlined, and they are integrated with a nonlinear beam model for the full description of the dynamics of a free-flying flexible vehicle. Nonlinear time-marching solutions capture large wing excursions and wake roll-up, and the linearisation of the equations lends itself to a seamless, monolithic state-space assembly, particularly convenient for stability analysis and flight control system design. The numerical studies emphasise scenarios where the Unsteady Vortex-Lattice Method can provide an advantage over other state-of-the-art approaches. Examples of this include unsteady aerodynamics in vehicles with coupled aeroelasticity and flight dynamics, and in lifting surfaces undergoing complex kinematics, large deformations, or in-plane motions. Geometric nonlinearities are shown to play an instrumental, and often counter-intuitive, role in the aircraft dynamics. The Unsteady Vortex-Lattice Method is unveiled as a remarkable tool that can successfully incorporate all those effects in the unsteady aerodynamics modelling
Overview of (pro-)Lie group structures on Hopf algebra character groups
Character groups of Hopf algebras appear in a variety of mathematical and
physical contexts. To name just a few, they arise in non-commutative geometry,
renormalisation of quantum field theory, and numerical analysis. In the present
article we review recent results on the structure of character groups of Hopf
algebras as infinite-dimensional (pro-)Lie groups. It turns out that under mild
assumptions on the Hopf algebra or the target algebra the character groups
possess strong structural properties. Moreover, these properties are of
interest in applications of these groups outside of Lie theory. We emphasise
this point in the context of two main examples: The Butcher group from
numerical analysis and character groups which arise from the Connes--Kreimer
theory of renormalisation of quantum field theories.Comment: 31 pages, precursor and companion to arXiv:1704.01099, Workshop on
"New Developments in Discrete Mechanics, Geometric Integration and
Lie-Butcher Series", May 25-28, 2015, ICMAT, Madrid, Spai
Advances in methods for determining fecundity: application of the new methods to some marine fishes
17 pages, 9 figures, 6 tables.Estimation of individual
egg production (realized fecundity)
is a key step either to understand
the stock and recruit relationship
or to carry out fisheries-independent
assessment of spawning stock
biomass using egg production methods.
Many f ish are highly fecund
and their ovaries may weigh over a
kilogram; therefore the work time
can be consuming and require large
quantities of toxic fixative. Recently
it has been shown for Atlantic cod
(Gadus morhua) that image analysis
can automate fecundity determination
using a power equation that
links follicles per gram ovary to the
mean vitellogenic follicular diameter
(the autodiametric method).
In this article we demonstrate the
precision of the autodiametric method
applied to a range of species with different
spawning strategies during
maturation and spawning. A new
method using a solid displacement
pipette to remove quantitative fecundity
samples (25, 50, 100, and 200 milligram
[mg]) is evaluated, as are the
underlying assumptions to effectively
fix and subsample the ovary. Finally,
we demonstrate the interpretation of
dispersed formaldehyde-fixed ovarian
samples (whole mounts) to assess the
presence of atretic and postovulatory
follicles to replace labor intensive histology.
These results can be used to
estimate down regulation (production
of atretic follicles) of fecundity during
maturation.T his study was jointly funded under Eu ropean
Union Frame Work V Q5RS -2002 - 01825 and the
Institutes in England (Department of the Environment,
Food, and Rural Affairs), Norway (Institute
of Marine Research), and Spain (Consejo Superior
de Investigaciones Científ icas, and A ZTI Tecnalia
(publication number 424))Peer reviewe
Concept note for ICCAT ecoregion workshop identification of regions in the ICCAT convention area for supporting the implementation of ecosystem based fisheries management
The overall aim of the workshop is to advance in the identification of candidate ecologically
meaningful regions that can serve as a basis to produce a more integrated ecosystem-based
advice, and thereby support the implementation and operationalization of ecosystem-based
fisheries management (EBFM) in the International Commission for the Conservation of Atlantic
Tunas (ICCAT) convention area. The candidate regions should have boundaries that make
ecological sense, and are practical in informing fisheries management. The workshop will gather
CPC national scientists and external experts from different scientific disciplines (e.g.
biogeography, oceanography, ecology, fisheries and fisheries management in the ICCAT area)
to develop a “proof of concept” for broad-scale regionalization of the ICCAT convention area.L'objectif général de l'atelier est de progresser dans l'identification de possibles régions
écologiquement significatives qui peuvent servir de base pour produire un avis écosystémique
plus intégré, et ainsi soutenir la mise en œuvre et la mise en marche de la gestion des pêcheries
basée sur les écosystèmes (EBFM) dans la zone de la Convention de la Commission
internationale pour la conservation des thonidés de l'Atlantique (ICCAT). Les régions candidates
doivent avoir des limites qui ont un sens écologique, et qui sont pratiques pour renseigner la
gestion des pêcheries. L'atelier réunira des scientifiques nationaux des CPC et des experts
externes de différentes disciplines scientifiques (par exemple, la biogéographie, l'océanographie,
l'écologie, la pêche et la gestion des pêcheries dans la zone de l'ICCAT) afin de développer une
preuve conceptuelle pour une régionalisation à grande échelle de la zone de la Convention
ICCATEl objetivo global del taller es avanzar en la identificación de posibles regiones ecológicamente
significativas que puedan servir como base para formular un asesoramiento basado en el
ecosistema más integrado, apoyando la implementación y puesta en marcha de la ordenación
pesquera basada en el ecosistema (EBFM) en la zona del Convenio de la Comisión Internacional
para la Conservación del Atún Atlántico (ICCAT). Las regiones candidatas deberían tener límites
que tengan sentido ecológico y que sean prácticas para aportar información a la ordenación
pesquera. El taller reunirá a científicos nacionales de las CPC y a expertos externos de diversas
disciplinas (por ejemplo, biogeografía, oceanografía, ecología, pesca y ordenación pesquera en
la zona de ICCAT) para desarrollar una demostración conceptual para una regionalización a
gran escala de la zona del Convenio de ICCAT.Versión del edito
Symplectic integrators with adaptive time steps
In recent decades, there have been many attempts to construct symplectic
integrators with variable time steps, with rather disappointing results. In
this paper we identify the causes for this lack of performance, and find that
they fall into two categories. In the first, the time step is considered a
function of time alone, \Delta=\Delta(t). In this case, backwards error
analysis shows that while the algorithms remain symplectic, parametric
instabilities arise because of resonance between oscillations of \Delta(t) and
the orbital motion. In the second category the time step is a function of phase
space variables \Delta=\Delta(q,p). In this case, the system of equations to be
solved is analyzed by introducing a new time variable \tau with dt=\Delta(q,p)
d\tau. The transformed equations are no longer in Hamiltonian form, and thus
are not guaranteed to be stable even when integrated using a method which is
symplectic for constant \Delta. We analyze two methods for integrating the
transformed equations which do, however, preserve the structure of the original
equations. The first is an extended phase space method, which has been
successfully used in previous studies of adaptive time step symplectic
integrators. The second, novel, method is based on a non-canonical
mixed-variable generating function. Numerical trials for both of these methods
show good results, without parametric instabilities or spurious growth or
damping. It is then shown how to adapt the time step to an error estimate found
by backward error analysis, in order to optimize the time-stepping scheme.
Numerical results are obtained using this formulation and compared with other
time-stepping schemes for the extended phase space symplectic method.Comment: 23 pages, 9 figures, submitted to Plasma Phys. Control. Fusio
On the construction of high-order force gradient algorithms for integration of motion in classical and quantum systems
A consequent approach is proposed to construct symplectic force-gradient
algorithms of arbitrarily high orders in the time step for precise integration
of motion in classical and quantum mechanics simulations. Within this approach
the basic algorithms are first derived up to the eighth order by direct
decompositions of exponential propagators and further collected using an
advanced composition scheme to obtain the algorithms of higher orders. Contrary
to the scheme by Chin and Kidwell [Phys. Rev. E 62, 8746 (2000)], where
high-order algorithms are introduced by standard iterations of a force-gradient
integrator of order four, the present method allows to reduce the total number
of expensive force and its gradient evaluations to a minimum. At the same time,
the precision of the integration increases significantly, especially with
increasing the order of the generated schemes. The algorithms are tested in
molecular dynamics and celestial mechanics simulations. It is shown, in
particular, that the efficiency of the new fourth-order-based algorithms is
better approximately in factors 5 to 1000 for orders 4 to 12, respectively. The
results corresponding to sixth- and eighth-order-based composition schemes are
also presented up to the sixteenth order. For orders 14 and 16, such highly
precise schemes, at considerably smaller computational costs, allow to reduce
unphysical deviations in the total energy up in 100 000 times with respect to
those of the standard fourth-order-based iteration approach.Comment: 23 pages, 2 figures; submitted to Phys. Rev.
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