1,101 research outputs found
La descoberta dels Pirineus a partir de dos fons fotogràfica conservats a l'Arxiu Històric del Col·legi d'arquitectes de Girona. Joan Xicart Rigual i Rafael Masó Valentí
Ll'Arxiu Històric de la Demarcació de Girona del Col·legi d'Arquitectes de Catalunya custodia dos fons fotogràfics poc coneguts que testimonien l'interès per la descoberta del país i, en especial, pel Pirineu, que es viu a la Catalunya de principis del segle XX. Ens referim al fons del fotograf amateur barceloní Joan Xicart Rigual (1878-1954) i el de l'arquitecte noucentista giro´ní Rafael Masó Valentí (1880-1935). Ambdós sób fons amplis i temàticament rics, amb 1358 i 1394 plaques estereoscòpiques , respectivament, que revelen els interessos dels fotògrafs i del seu temps
Study of Some Planetary Atmospheres Features by Probe Entry and Descent Simulations
Characterization of planetary atmospheres is analyzed by its effects in the entry and descent trajectories of probes. Emphasis is on the most important variables that characterize atmospheres e.g. density profile with altitude. Probe trajectories are numerically determined with ENTRAP, a developing multi-purpose computational tool for entry and descent trajectory simulations capable of taking into account many features and perturbations. Real data from Mars Pathfinder mission is used. The goal is to be able to determine more accurately the atmosphere structure by observing real trajectories and what changes are to expect in probe descent trajectories if atmospheres have different properties than the ones assumed initially
Relational Extensions : Object-Relational and XML Extensions
Mòdul 2 del llibre Database Architecture. UOC, 20122022/202
General dissipation coefficient in low-temperature warm inflation
In generic particle physics models, the inflaton field is coupled to other
bosonic and fermionic fields that acquire large masses during inflation and may
decay into light degrees of freedom. This leads to dissipative effects that
modify the inflationary dynamics and may generate a nearly-thermal radiation
bath, such that inflation occurs in a warm rather than supercooled environment.
In this work, we perform a numerical computation and obtain expressions for the
associated dissipation coefficient in supersymmetric models, focusing on the
regime where the radiation temperature is below the heavy mass threshold. The
dissipation coefficient receives contributions from the decay of both on-shell
and off-shell degrees of freedom, which are dominant for small and large
couplings, respectively, taking into account the light field multiplicities. In
particular, we find that the contribution from on-shell decays, although
Boltzmann-suppressed, can be much larger than that of virtual modes, which is
bounded by the validity of a perturbative analysis. This result opens up new
possibilities for realizations of warm inflation in supersymmetric field
theories.Comment: 25 pages, 13 figures; revised version with new results added;
published in JCA
Indicators of the quality of the foster care
Una de las dificultades en la selección de las familias que se acercan al acogimiento familiar está relacionado con la falta de estudios que pudieran apuntar hacia características necesarias que apoyaran un desarrollo integral y comunitario óptimo del menor acogido y a su vez, en el proceso acogedor ayudar tanto a la familia como al menor para generar y/u optimizar aquellos recursos que permitan la consecución de las mismas. En una muestra de 53 familias que a lo largo tres años acogieron a 80 menores nuestro objetivo fue identificar las características que más habían favorecido el desarrollo del menor. Los resultados subrayan la importancia del establecimiento de vínculos seguros del menor con los acogedores, la integración del menor en la familia acogedora (la aparición de un sentido de pertenencia), la existencia de hijos en el núcleo de convivencia y una percepción de satisfacción con el acogimiento, por parte de la familia acogedora.One of the difficulties in choosing the families who come to foster care is related to the lack of studies that indicate the features needed to support optimal integrated development of children in foster care and also help in the process both the family as the child to generate the necessary resources. The sample consisted of 53 families with 80 children in foster care for three years. The aim was to identify characteristics that allow promote the development of the child. The results underline the importance of establishing secure links between the child and the foster family, the integration of the child in the foster family (the emergence of a sense of belonging), the existence of children in the foster family and a sense of satisfaction with welcoming, by the foster family.peerReviewe
Warming up for Planck
The recent Planck results and future releases on the horizon present a key
opportunity to address a fundamental question in inflationary cosmology of
whether primordial density perturbations have a quantum or thermal origin, i.e.
whether particle production may have significant effects during inflation. Warm
inflation provides a natural arena to address this issue, with interactions
between the scalar inflaton and other degrees of freedom leading to dissipative
entropy production and associated thermal fluctuations. In this context, we
present relations between CMB observables that can be directly tested against
observational data. In particular, we show that the presence of a thermal bath
warmer than the Hubble scale during inflation decreases the tensor-to-scalar
ratio with respect to the conventional prediction in supercooled inflation,
yielding , where is the tensor spectral index. Focusing on
supersymmetric models at low temperatures, we determine consistency relations
between the observables characterizing the spectrum of adiabatic scalar and
tensor modes, both for generic potentials and particular canonical examples,
and which we compare with the WMAP and Planck results. Finally, we include the
possibility of producing the observed baryon asymmetry during inflation through
dissipative effects, thereby generating baryon isocurvature modes that can be
easily accommodated by the Planck data.Comment: 14 pages, 10 figures. Published in JCA
Computer Networks Virtualization with GNS3: Evaluating a solution to optimize resources and achieve a distance learning
Designing educational resources allow students to modify their learning process. In particular, on-line and downloadable educational resources have been successfully used in engineering education the last years [1]. Usually, these resources are free and accessible from web. In addition, they are designed and developed by lecturers and used by their students. But, they are rarely developed by students in order to be used by other students. In this work-in-progress, lecturers and students are working together to implement educational resources, which can be used by students to improve the learning process of computer networks subject in engineering studies. In particular, network topologies to model LAN (Local Area Network) and MAN (Metropolitan Area Network) are virtualized in order to simulate the behavior of the links and nodes when they are interconnected with different physical and logical design.This work is supported by the “Computer Science Research Institute” of the University of Alicante through the aid “Internationalization and quality of the doctoral program”
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