4,547 research outputs found
Relations between static-structural aspects, construction phases and building materials of San Saturnino Basilica (Cagliari, Italy)
The construction site was used several times: in a first phase, in the republican era of Roman domination it hosted, probably, a temple whose height could reach 25 meters; in a second phase, during the Roman Empire, it was used as a burial area. Then around IV-V century AD a first Christian Basilica made of a naved building with an apse was built there, at the center of a large monastery. Subsequently in a third phase in VI century AD a Byzantine Martyrium, with a Greek cross-shaped plan, was built: the central part of it, supporting a dome is still standing. Finally after 1089 the church was given to Marsilian monks who deeply renovated it and changed its shape converting the plan to a Latin cross.
A macroscopic material analysis shows the presence of various rocks, whose use appears to be inhomogeneous during all construction phases. Sedimentary rocks (limestones, sandstones, calcarenites etc belonging to local geological formations) are generally used for masonry structures. Marbles, mostly coming from abroad and previously used in Roman buildings have been adopted for architectural elements (columns, capitals, and so on). At a lower extent there are masonry blocks in Oligo-Miocenic volcanic rocks and seldom stone materials which are not originally from Sardinia. Both mineralogical and petrographic tests (e.g. XRF, XRD) and the most important physical properties (porosity, density, water absorption coefficients, compressive, flexural and tensile strength, etc) show that many of the more representative samples of rock materials (like limestonss, calcarenits) are often highly decayed, with a corresponding reduction of their mechanical strength.
A structural analysis is particularly useful for helping in clarifying the historical evolution of the building, checking reconstruction hypotheses and assessing the true residual strength of the more important parts. An example, a FEM analysis of the Byzantine domed part is presented here
Dielectric correction to the Chiral Magnetic Effect
We derive an electric current density in the presence of a magnetic
field and a chiral chemical potential . We show that has
not only the anomaly-induced term (i.e. Chiral Magnetic
Effect) but also a non-anomalous correction which comes from interaction
effects and expressed in terms of the susceptibility. We find the correction
characteristically dependent on the number of quark flavors. The numerically
estimated correction turns out to be a minor effect on heavy-ion collisions but
can be tested by the lattice QCD simulation.Comment: 4 pages, 1 figur
Evaluating the phase diagram of superconductors with asymmetric spin populations
The phase diagram of a non-relativistic fermionic system with imbalanced
state populations interacting via a short-range S-wave attractive interaction
is analyzed in the mean field approximation. We determine the energetically
favored state for different values of the mismatch between the two Fermi
spheres in the weak and strong coupling regime considering both homogeneous and
non-homogeneous superconductive states. We find that the homogeneous
superconductive phase persists for values of the population imbalance that
increase with increasing coupling strength. In the strong coupling regime and
for large population differences the energetically stable homogeneous phase is
characterized by one gapless mode. We also find that the inhomogeneous
superconductive phase characterized by the condensate is energetically favored in a range of values
of the chemical potential mismatch that shrinks to zero in the strong coupling
regime.Comment: 9 pages, 5 figure
Option implied trees and implied moments
Implied trees are simple non-parametric discretizations of one- or two-dimension diffusions, aimed at introducing non-constant volatility in an option pricing model. The aim of the paper is twofold. First we investigate the ability of different option implied trees in pricing European options. Second, we compare the implied moments obtained with the use of option implied trees with the risk–neutral moments obtained with the use of Bakshi et al. (2003) formula and with realised physical moments. The comparison is pursued in the Italian market by analysing a data set which covers the years 2005-2009 and span both a relatively tranquil and a turmoil period. Keywords
Feasibility of an EHF (40/50 GHz) mobile satellite system using highly inclined orbits
The pan-European L-band terrestrial cellular system (GSM) is expected to provide service to more than 10 million users by the year 2000. Discussed here is the feasibility of a new satellite system at EHF (40/50 GHz) to complement, at the end of the decade, the GSM system or its decendants in order to provide additional services at 64 kbits/s, or so. The main system aspects, channel characteristics, technology issues, and both on-board and earth terminal architectures are highlighted. Based on the performed analyses, a proposal was addressed to the Italian Space Agency (ASI), aimed at the implementation of a national plan
On the ground state of gapless two flavor color superconductors
This paper is devoted to the study of some aspects of the instability of two
flavor color superconductive quark matter. We find that, beside color
condensates, the Goldstone boson related to the breaking of suffers of
a velocity instability. We relate this wrong sign problem, which implies the
existence of a Goldstone current in the ground state or of gluonic
condensation, to the negative squared Meissner mass of the gluon in
the g2SC phase. Moreover we investigate the Meissner masses of the gluons and
the squared velocity of the Goldstone in the multiple plane wave LOFF states,
arguing that in such phases both the chromo-magnetic instability and the
velocity instability are most probably removed. We also do not expect Higgs
instability in such multiple plane wave LOFF. The true vacuum of gapless two
flavor superconductors is thus expected to be a multiple plane wave LOFF state.Comment: 16 pages, RevTe3X4 styl
Presentation and item analysis of the IE-ACCME-B Test for measuring emotional and meta-emotional intelligence in children
This paper aims to present the initial findings and item analysis of the IE-ACCME-B test, a multi-method assessment tool specifically developed for evaluating emotional and meta-emotional intelligence in children aged 8 to 11 years. The IE-ACCME-B test was designed within the framework of the meta-emotional intelligence construct and has a dual purpose: 1) measuring emotional intelligence, defined as the ability to perceive, facilitate, understand, and manage emotions, and 2) assessing meta-emotional intelligence, which involves the belief system regarding emotions and
awareness of one's own emotional abilities in perceiving, facilitating, understanding, and managing emotions. The analysis of results and items was conducted using CUB models and by examining children's consensus scores
Hot Quark Matter with an Axial Chemical Potential
We analyze the phase diagram of hot quark matter in presence of an axial
chemical potential, . The latter is introduced to mimic the chirality
transitions induced, in hot Quantum Chromodynamics, by the strong sphaleron
configurations. In particular, we study the curvature of the critical line at
small , the effects of a finite quark mass and of a vector interaction.
Moreover, we build the mixed phase at the first order phase transition line,
and draw the phase diagram in the chiral density and temperature plane. We
finally compute the full topological susceptibility in presence of a background
of topological charge.Comment: 12 pages, 7 figures. Few references added, short discussion included.
Final version appearing on Phys. Rev.
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