702 research outputs found
Support Vector Motion Clustering
This work was supported in part by the Erasmus Mundus Joint Doctorate in Interactive and Cognitive Environments (which is funded by the EACEA Agency of the European Commission under EMJD ICE FPA n 2010-0012) and by the Artemis JU and the UK Technology Strategy Board through COPCAMS Project under Grant 332913
The 2020 IDS release of the Antwerp COR*-database. Evaluation, development and transformation of a pre-existing database
The Antwerp COR*-IDS database 2020 is a transformed and harmonized historical demographic database
in a cross-nationally comparable format designed to be open and easy to use for international researchers.
The database is constructed from the 2010 release of the Antwerp COR*-historical demographic database,
which was created using a letter sample of the whole district of Antwerp (Flanders, Belgium). It has a
total sample size of +/- 33,000 residents of Antwerp. The sample spans nearly seven decades. The data is
collected from historical records: including population registers and vital registration records covering births,
marriages, in/external migrations and deaths. The database covers up to three linked generations (in some
cases more), and contains micro-data on individual level life courses, and relationships deriving from addressbased
household composition methods. An important characteristic is the sample's large migrant population,
including the timings of their demographic events and living arrangements, whilst resident in the district of
Antwerp. In addition, the sample also contains a large array of occupational level information. This paper
presents the processes, methodologies and documentation regarding the evaluation and development of a
pre-existing historical database. This includes the systematic evaluation of the original samples, methodologies
for address based reconstructing of households, and the geocoding of a historical database which took place
during the current development of this new version of the database.info:eu-repo/semantics/publishedVersio
Chasma Boreale, Mars: A Sapping and Outflow Channel with a Tectono-thermal Origin
A detailed geomorphological study of Chasma Boreale, a widely known feature of Mars’ north polar cap, has been carried out for the first time, along with a quantitative paleohydro logical model. It is concluded that the chasma was eroded by a flow whose discharge was on the order of magnitude of 109 m sec21. This catastrophic flow is thought to have been preceded
by a powerful sapping process, caused by a tectonic control in the distribution and present aspect of most of the polar troughs. This tectonic forcing probably played a major role in the inception of not only Chasma Boreale but also
other polar reentrants as wel
Parabolic trough collectors. Fundamentals of heat transfer applied to solar thermal energy.
Solar thermal energy has undergone major development in recent years. The most
widely used technologies are central receiver solar towers and parabolic trough collectors (PTC)[1]. The latter technology has great advantages due to its higher optical
and thermal efficiency, but, despite being a well-proven technique, it presents certain
problems inherent to the manufacturing and durability of some critical elements in
the system. They are generally composed of an absorber tube surrounded by a glass
cover and in the intermediate space, a vacuum is created to minimize thermal losses
by convection[2]. The absorber tube is located at the focal line of a parabolic mirror
that concentrates sun’s rays. To predict the thermal behavior of this type of system,
ray-tracing techniques are used to determine the thermal load and accurate correlations are also needed to calculate the convective heat transfer. Also, the original design
shows some problems such as the selective coating applied on the absorber surface,
whose thermal performance decays with time. Besides, the metal-glass welding are
also a significant weak spot, which due to the thermal expansion can cause the partial
or total loss of the vacuum in the aforementioned annulus. In this work we present the
results of the modeling of this type of systems in different working configurations, as
well as a new design proposal to improve the thermal transfer in this type of systems.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Fomento del aprendizaje autónomo en una asignatura de computadores paralelos
Este trabajo presenta una actividad diseñada para una asignatura de arquitectura de computadores que estudia computadores paralelos. Se propuso para fomentar que los alumnos trabajen la asignatura durante todo el cuatrimestre, facilitar el estudio de los contenidos de la asignatura, mejorar la opinión de los alumnos sobre estos contenidos y favorecer el aprendizaje autónomo y una actitud reflexiva. La actividad consiste en un trabajo sobre un computador paralelo concreto y en uso. Los alumnos tienen que aplicar los contenidos de la asignatura al computador paralelo buscando información sobre éste en publicaciones especializadas y en páginas web y documentación de fabricantes y vendedores. La actividad se ha evaluado mediante una encuesta de opinión. Los resultados de ésta reflejan que contribuye a alcanzar los objetivos esperados
Active Sampling-based Binary Verification of Dynamical Systems
Nonlinear, adaptive, or otherwise complex control techniques are increasingly
relied upon to ensure the safety of systems operating in uncertain
environments. However, the nonlinearity of the resulting closed-loop system
complicates verification that the system does in fact satisfy those
requirements at all possible operating conditions. While analytical proof-based
techniques and finite abstractions can be used to provably verify the
closed-loop system's response at different operating conditions, they often
produce conservative approximations due to restrictive assumptions and are
difficult to construct in many applications. In contrast, popular statistical
verification techniques relax the restrictions and instead rely upon
simulations to construct statistical or probabilistic guarantees. This work
presents a data-driven statistical verification procedure that instead
constructs statistical learning models from simulated training data to separate
the set of possible perturbations into "safe" and "unsafe" subsets. Binary
evaluations of closed-loop system requirement satisfaction at various
realizations of the uncertainties are obtained through temporal logic
robustness metrics, which are then used to construct predictive models of
requirement satisfaction over the full set of possible uncertainties. As the
accuracy of these predictive statistical models is inherently coupled to the
quality of the training data, an active learning algorithm selects additional
sample points in order to maximize the expected change in the data-driven model
and thus, indirectly, minimize the prediction error. Various case studies
demonstrate the closed-loop verification procedure and highlight improvements
in prediction error over both existing analytical and statistical verification
techniques.Comment: 23 page
El origen glaciar de la aureola del volcán Arsia Mons, Marte
Huge lobate deposits called aureoles are covering the base of the giant Martian volcanic constructs of Tharsis dome. The origin of these structures has been a matter of debate between two competing hypotheses: volcanic landslides or mountain glaciers. Here we consider the most important of the aureoles, near Arsia Mons, concluding that the glacier model explains best the deposit features, such as the layering, the ridges (interpreted as glaciotectonic ones), and the lobated terrain. We then discuss the fit of these proposed glacier deposits in the present paleoclimatic Martian models. The aureoles could be key elements in the confirmation of the «Baker cycle» model of repeated episodes of temperate, humid, sea-dominated climates coincident in time with the outflow channels activity.Al pie de los grandes volcanes marcianos del domo de Tharsis aparecen unas formas lobuladas que han recibido el nombre de aureolas. El origen de estas estructuras ha sido objeto de un largo debate entre dos hipótesis principales que las interpretan como deslizamientos de ladera o como glaciares de montaña. En este trabajo se estudia la mejor desarrollada de estas aureolas, la de Arsia Mons, llegándose a la conclusión de que la hipótesis glaciar explica mejor las características del depósito, y en concreto la existencia de estratificación, las crestas (que se interpretan como glaciotectónicas) y los terrenos lobulados. Por último se discute la conexión de estos depósitos con los modelos paleoclimáticos actuales sobre Marte, lo que lleva a la conclusión de que las aureolas deben ser depósitos glaciares recientes relacionados con repetidos episodios de clima cálido (ciclos de Baker), provocados por la acción de los canales de desbordamiento
The ALMA Frontier Fields Survey - IV. Lensing-corrected 1.1 mm number counts in Abell 2744, MACSJ0416.1-2403 and MACSJ1149.5+2223
[abridged] Characterizing the number counts of faint, dusty star-forming
galaxies is currently a challenge even for deep, high-resolution observations
in the FIR-to-mm regime. They are predicted to account for approximately half
of the total extragalactic background light at those wavelengths. Searching for
dusty star-forming galaxies behind massive galaxy clusters benefits from strong
lensing, enhancing their measured emission while increasing spatial resolution.
Derived number counts depend, however, on mass reconstruction models that
properly constrain these clusters. We estimate the 1.1 mm number counts along
the line of sight of three galaxy clusters, i.e. Abell 2744, MACSJ0416.1-2403
and MACSJ1149.5+2223, which are part of the ALMA Frontier Fields Survey. We
perform detailed simulations to correct these counts for lensing effects. We
use several publicly available lensing models for the galaxy clusters to derive
the intrinsic flux densities of our sources. We perform Monte Carlo simulations
of the number counts for a detailed treatment of the uncertainties in the
magnifications and adopted source redshifts. We find an overall agreement among
the number counts derived for the different lens models, despite their
systematic variations regarding source magnifications and effective areas. Our
number counts span ~2.5 dex in demagnified flux density, from several mJy down
to tens of uJy. Our number counts are consistent with recent estimates from
deep ALMA observations at a 3 level. Below 0.1 mJy, however,
our cumulative counts are lower by 1 dex, suggesting a flattening in
the number counts. In our deepest ALMA mosaic, we estimate number counts for
intrinsic flux densities 4 times fainter than the rms level. This
highlights the potential of probing the sub-10 uJy population in larger samples
of galaxy cluster fields with deeper ALMA observations.Comment: 19 pages, 14 figures, 3 tables. Accepted for publication in A&
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