Search results for " Infrared thermography"
showing 10 items of 11 documents
Seismic and non‐invasive geophysical surveys for the renovation project of Branciforte Palace in Palermo
2020
The renovation project of the historic Branciforte Palace (16th–17th century) in Palermo (Italy) was owned by the Banco di Sicilia Foundation, with the aim for it to become a multi-purpose centre for the promotion of exhibitions and cultural events. In the context of the restoration work, a multi-methodological and non-invasive geophysical study has been carried out. The seismic characterization of the foundation soils was obtained by means of joint interpretations of a vertical seismic profile (VSP), multichannel analysis of surface waves (MASW) and horizontal to vertical spectral ratio (HVSR) microtremor analysis. The mutually constrained inversion of seismic surveys carried out with diff…
Thermal NDT of glass reinforced composite panels for naval applications by means of a linear infrared scanner
2009
The work describes the development and application of a low cost Thermal NDT set-up to investigate the influence of delamination defects on thick glass fibre reinforced composite laminates simulating typical hull monolithic GRP panels. Two active thermographic techniques have been implemented in particular: a pulsed thermography and a step heating scheme. A 12 mm thick cross-ply panel has been manufactured and delamination defects simulated in two different ways: by embedding patches of folded Teflon sheets, and by drilling flat bottomed back holes. A number of defects was then positioned at three different depths form the scanned surfaces, measuring ¼, ½ and ¾ of the laminate thickness. A …
THE ROLE OF THERMOGRAPHY IN THE NON-DESTRUCTIVE EVALUATION OF HISTORICAL ARCHITECTURAL SURFACES. Some observation about the method and its purpose
2014
Infrared-Thermography (IRT) has become a supporting tool for the investigation of historical structures and facades. Using the non-destructive testing method for the detection can give a profound knowledge about the current status of the object and the state of decay, about different kinds of discontinuities at historical facades, of construction details and of thermal bridges in the facades. Different case studies of thermographic surveys on some Sicilian monuments are presented and discussed to illustrate how the method can offer applicable information about the investigated objects and demonstrate its reasonable integration into conservation projects.
Comparing different processing methods in apple slice drying. Part 1. Performance of microwave, hot air and hybrid methods at constant temperatures
2019
The drying curves, energy efficiency and colour variations of sliced apples dried at various temperatures and using different techniques were evaluated, i.e. microwave (35, 55 and 65 °C), hot air (35, 55, 65 and 75 °C) and combination of both (65 °C). The microwave (MW) tests also included comparison between air recirculation and continuous inlet of fresh air. Each drying method was evaluated at a fixed temperature level by means of a control system based on infrared thermography. The time required to complete the drying process at 65 °C varied from about 44 min for MW with fresh air ventilation (double with air recirculation), to 122 min for hybrid heating and 238 min for hot air. Drying k…
Influence of mode stirrer and air renewal on controlled microwave drying of sliced zucchini
2017
An on-line temperature-controlled microwave (MW) system, based on infrared thermography, was developed for drying zucchini slices. Moreover, the effects of different configurations, including turntable rotation, mode stirrer and air renewal, alone or in combination, on drying kinetics and quality of dried product were evaluated. The combination of stirrer and air renewal reduced the drying time of zucchini slices by about 48% with respect to the basic configuration and by 22% with respect to air renewal only. The lowest oscillation of temperatures about the fixed level (65 °C) was found when operating with the stirrer mode, because of the improved uniformity of the MW distribution. The sa…
ARCHITECTURAL SURVEY TECHNIQUES FOR DEGRADATION DIAGNOSTICS. AN APPLICATION FOR THE CULTURAL HERITAGE
2021
Abstract. The great technological development in recent years in the field of architectural survey has made possible increasingly expeditious and less invasive investigations with the aim of acquiring a series of data related to the asset and fundamental for the protection of cultural heritage. In addition, the synergy between the various techniques represents an added value able, not only, to fill possible gaps and lacks arising from application limits of the instruments, but also to enhance the peculiarities of the same. This paper presents an integrated survey activity (range-based, image-based and IR thermography techniques) aimed at applying the combination and collaboration of multipl…
Drying rate control in microwave assisted processing of sliced apples
2018
The most enhanced microwave systems for the preparation of quality-dehydrated fruits continuously adjust the power level in order to maintain the product temperature above a target value. As a result, typical drying curves that exhibit high drying rates in the middle stage are obtained. This can often lead to quality damage or undesirable changes on food colour and texture. In response to these issues, a microwave system is proposed that can realise drying processes keeping drying rates constant. This approach required a continuous temperature adjustment of the apple slices under test, whose temperature was detected by a computer-aided infrared thermography system. Since temperature correct…
IMPLEMENTAZIONE DI TECNICHE DI TERMOGRAFIA ATTIVA IRNDT SU COMPOSITI GRP MEDIANTE LA DEPOSIZIONE DI IMPULSI TERMICI DI LUNGA DURATA
2011
Nel presente lavoro viene analizzata l’implementazione di tecniche attive di termografia ad infrarossi per analisi NDT su pannelli in composito. In particolare si propone l’uso di lampade alogene come sorgente di calore esterna, le quali richiedono tempi di accensione dell’ordine di diversi secondi al fine di depositare efficaci quantità di calore. Si discutono quindi le problematiche connesse all’implementazione di tecniche di Transient Thermography e di Lock-In Thermography in presenza di tempi lunghi di deposizione di calore. Viene implementata una tecnica di modulazione della deposizione di calore mediante treni di onde quadre di lunga durata (PMLT - Pulse Modulated Lock-In Thermography…
Deep learning strategies for automatic fault diagnosis in photovoltaic systems by thermographic images
2021
Abstract Losses of electricity production in photovoltaic systems are mainly caused by the presence of faults that affect the efficiency of the systems. The identification of any overheating in a photovoltaic module, through the thermographic non-destructive test, may be essential to maintain the correct functioning of the photovoltaic system quickly and cost-effectively, without interrupting its normal operation. This work proposes a system for the automatic classification of thermographic images using a convolutional neural network, developed via open-source libraries. To reduce image noise, various pre-processing strategies were evaluated, including normalization and homogenization of pi…
Joint Investigation with Ground Penetrating Radar and Infrared Thermography as a Diagnostic Support for the Restoration of Two Wall Mosaics in the Ch…
2022
The church of S. Mary of the Admiral in Palermo, known as “La Martorana” and very famous for its Byzantine mosaics, has been a World Heritage site since 2015. The mosaic system of the church includes several groups of figures and scenes from the life of the Virgin Mary. From the western part of the ancient church only two mosaics survive, detached from their original position, and are now located in two internal chapels. On the occasion of several restoration works, these two mosaic panels were investigated with non-invasive techniques, in order to provide diagnostic support to the restoration and consolidation interventions. The investigations were aimed at detecting any air po…