Monitoraggio topografico e fotogrammetrico della cupola del teatro Massimo

L’articolo riporta i primi risultati di uno studio finalizzato al monitoraggio delle deformazioni della cupola del Teatro Massimo di Palermo provocate dalle dilatazioni termiche, con l’impiego di tecniche topografiche e fotogrammetriche integrate. In particolare, sono state utilizzate due stazioni totali robotizzate e sistemi di fotogrammetria digitale di elevata precisione. Per correlare gli spostamenti dei carrelli sui quali poggia la struttura in acciaio della cupola con i gradienti termici, sono state acquisite immagini termiche diversificate. L’obiettivo principale del lavoro consisteva nel confronto delle due tecniche di rilievo in relazione a misure di deformazione di entità molto ridotta (sub-millimetrica). I risultati ottenuti dimostrano che i carrelli funzionano ancora correttamente. Infatti, per un gradiente termico di 6°C misurato dalla termo camera, entrambe le tecniche topografiche e fotogrammetriche hanno evidenziato spostamenti dell’ordine di 0.8 mm, in accordo con le previsioni del modello deformativo teorico

Geomatic applications tourban park in palermo

Over the last few years topographical techniques have developed an exponential trend towards simplifying and speeding, both survey operations and analysis of data collected reaching at the same time ever higher levels of accuracy. Among the technologies that are increasingly taking the field in this context is part of the Mobile Mapping System (MMS) that, on any mobile platform, combines sensors and measurement systems designed to provide a 3D position of the platform and, at the same time, capable to acquire geographic data without the aid of control points on the ground. The study reported concerns the verification of the reliability metrics and a qualitative MMS in order to evaluate its behavior in a particularly insidious as it can be an urban park; in particular, we report a series of experiments carried out from 2012 to the present in which we tried to test the potential of the system, comparing it with data from systems more “traditional”, and to exploit all the products in an integrated survey carried out in dynamic mode

GEOMATIC METHODOLOGIES FOR THE STUDY OF TEATRO MASSIMO IN PALERMO (ITALY)

This work illustrates the use of geomatics techniques for the documentation of Teatro Massimo in Palermo (Italy), one of the most important and big in Italy and in Europe. The theatre is characterized by a very complex structure and is realized also using innovative solution, studied at the time of the project specifically for this building; for example, an original system was realized for a natural air-conditioning system of the auditorium. Due to his complexity, the documentation of the Teatro Massimo requires studying specific survey solutions for the different parts of the building. In this paper, some studies on two of the most representative parts of the building were described. In particular, a 3D survey of the auditorium was carried out to obtain a first 3D model of the most important internal part; a very accurate monitoring of structure inside the dome of the theatre was also carried out. The survey of the auditorium was realized by a Terrestrial Laser Scanning (TLS), that has allowed the creation of a digital archive of point clouds, showing, however, the some level of criticality due to the complex shapes of building and of architectural details. The work has highlighted that specific strategy to optimize the number of acquisitions needed for the complete documentation of the auditorium. The monitoring of the structure inside the dome was carried out by topographic and photogrammetric techniques. The monitoring was aimed at measuring the displacements of the support devices connecting the iron structure of the dome. The monitoring has allowed to understand and to test the proper functionality of this complex system. Some tests were carried out also by a thermal camera to correlate the displacements of the support devices with the dilatations produced by steel thermal gradients

Genotype influence on shelf life behaviour of minimal processed loquat (Eriobotrya japonica (Thunb.) Lindl.) fruit: the role of sugar, acid organics and phenolic compounds

Background: Loquat cultivars cultivated in Southern Italy are very appreciated by consumers for their sensorial characteristics, such as persistent aroma and taste. Apposite maturity indexes for peeling and processing loquat fruit were investigated to increase diffusion of minimally processed loquat. The genotype’s effect on the minimally processed loquat fruit shelf life and quality harvested at commercial maturity (80% yellow color) was investigated on peeled fruit stored at 5 °C for 10 days. The role of sugars, organic acids and phenols composition was observed through in depth qualitative analysis. In addition, several qualitative analyses were carried out to determine the quality of minimal processed fruit. Results: Loquat fruits harvested at commercial ripening stage performed very good palatability and flesh color persistency. Late ripening fruits genotypes shown a low rate of pulp oxidation and quality decay, while early ripening fruits were not suitable for fresh-cut. Genotype had a great influence on weight loss, β-carotene content, fruit respiration, ascorbic acid and total phenols content during the shelf life. Conclusions: This work shows how the amount of the composition of sugars and organic acids as an intrinsic characteristic of genotype influences the quality of loquat fruits minimal processed. The higher values of glucose, sorbitol and ascorbic acid accumulated in the cv ‘Nespolone Trabia’ contributed to a reduction in chilling injury and oxidative stress after cutting. Graphical Abstract: [Figure not available: see fulltext.

Monitoraggio delle deformazioni della cupola del Teatro Massimo di Palermo con l\u2019impiego di tecniche topografiche e fotogrammetriche integrate.

L\u2019articolo riporta i primi risultati di uno studio finalizzato al monitoraggio delle deformazioni della cupola del Teatro Massimo di Palermo provocate dalle dilatazioni termiche, con l\u2019impiego di tecniche topografiche e fotogrammetriche integrate. In particolare, sono state utilizzate due stazioni totali robotizzate e sistemi di fotogrammetria digitale di elevata precisione. Per correlare gli spostamenti dei carrelli sui quali poggia la struttura in acciaio della cupola con i gradienti termici, sono state acquisite immagini termiche diversificate. L\u2019obiettivo principale del lavoro consisteva nel confronto delle due tecniche di rilievo in relazione a misure di deformazione di entit\ue0 molto ridotta (submillimetrica). I risultati ottenuti dimostrano che i carrelli funzionano ancora correttamente. Infatti, per un gradiente termico di 6\ub0 C misurato dalla termo camera, entrambe le tecniche topografiche e fotogrammetriche hanno evidenziato spostamenti dell\u2019ordine di 0.8 mm, in accordo con le previsioni del modello teorico.This paper shows the first results of a study aimed at monitoring the deformations of the dome of the Massimo Theatre in Palermo caused by thermal dilatations, with the use of topographic and photogrammetric integrated techniques. Particularly, two robotic total stations and high precision digital photogrammetric systems were employed. In order to correlate the displacements of the rollers on which the steel structure of the dome rest with the thermal gradients, different thermal images were acquired. The main goal of the work was to compare the two techniques with reference to very small (sub-millimeter) deformation measurements. The obtained results show that the rollers are still working correctly. In fact, for a thermal gradient of 6 \ub0C surveyed by thermographic camera, both topographic and photogrammetric techniques determined displacements of the order of 0.8 mm, according with the expected deformations of the theoretic model

Scattering of slow-light gap solitons with charges in a two-level medium

The Maxwell-Bloch system describes a quantum two-level medium interacting with a classical electromagnetic field by mediation of the the population density. This population density variation is a purely quantum effect which is actually at the very origin of nonlinearity. The resulting nonlinear coupling possesses particularly interesting consequences at the resonance (when the frequency of the excitation is close to the transition frequency of the two-level medium) as e.g. slow-light gap solitons that result from the nonlinear instability of the evanescent wave at the boundary. As nonlinearity couples the different polarizations of the electromagnetic field, the slow-light gap soliton is shown to experience effective scattering whith charges in the medium, allowing it for instance to be trapped or reflected. This scattering process is understood qualitatively as being governed by a nonlinear Schroedinger model in an external potential related to the charges (the electrostatic permanent background component of the field).Comment: RevTex, 14 pages with 5 figures, to appear in J. Phys. A: Math. Theo