Search results for " meccanica"
showing 10 items of 819 documents
Machine learning at the interface of structural health monitoring and non-destructive evaluation
2020
While both non-destructive evaluation (NDE) and structural health monitoring (SHM) share the objective of damage detection and identification in structures, they are distinct in many respects. This paper will discuss the differences and commonalities and consider ultrasonic/guided-wave inspection as a technology at the interface of the two methodologies. It will discuss how data-based/machine learning analysis provides a powerful approach to ultrasonic NDE/SHM in terms of the available algorithms, and more generally, how different techniques can accommodate the very substantial quantities of data that are provided by modern monitoring campaigns. Several machine learning methods will be illu…
A decision support system based on multisensor data fusion for sustainable greenhouse management
2018
The sustainable exploitation of natural resources is nowadays an important challenge for governments and institutions, considering the expected increase of the world population. In order to respond to this emergent criticality, the principles of green economy have been introduced in the European policy discussion to achieve a good compromise between the sustainability and the profitability of productions by increasing the efficiency of farming operations. Such approach poses some technical and financial challenges for small-sized enterprises because they generally do not possess adequate internal knowledge, nor they can acquire external expertise due to their budget restrictions. Decision S…
Laser Ultrasonics Inspection of Train Wheel - Evaluation of Optimized Setup
2021
In the railway field, the safety of passengers and the service life of train components are a crucial issue. For this reason, continuous periodic inspections by non-destructive techniques are required. Among these, ultrasonic tests are widely used in this field, even though the conventional ultrasound techniques have the disadvantage of requiring the disassembly of the wheels and of putting the train out of service. This procedure is expensive and time-consuming and can be neglected if non-contact ultrasonic techniques are used. In this work, the authors present an experimental research on some defects, artificially obtained on a railway wheel supplied by Trenitalia Spa, by adopting three d…
NUMERICAL-EXPERIMENTAL METHOD FOR THE ANALYSIS OF RESIDUAL STRESSES IN COLD-EXPANDED HOLES
2012
Hole cold expansion is a technique widely used to improve the fatigue life of components with holes, e.g. bolted or riveted joints. As it has been demonstrated in literature by analytical, numerical and experimental analyses carried out by several authors, the compressive residual stresses introduced by the hole cold expansion have a beneficial influence on both the static and the fatigue strength of the treated component, because they reduce significantly the typical stress peaks around the hole due to stress concentration. In the literature, various analyses of the residual stresses introduced by the hole cold expansion have been performed by using several methods such as X-ray diffractio…
Measuring Inaccessible Residual Stresses Using Multiple Methods and Superposition
2010
The traditional contour method maps a single component of residual stress by cutting a body carefully in two and measuring the contour of the cut surface. The cut also exposes previously inaccessible regions of the body to residual stress measurement using a variety of other techniques, but the stresses have been changed by the relaxation after cutting. In this paper, it is shown that superposition of stresses measured post-cutting with results from the contour method analysis can determine the original (pre-cut) residual stresses. The general superposition theory using Bueckner’s principle is developed and limitations are discussed. The procedure is experimentally demonstrated by determini…
Experimental assessment of the shield-to-salt-fog properties of basalt and glass fiber reinforced composites in cork core sandwich panels applications
2018
Abstract In this paper, the effect of salt-fog exposition on the mechanical behavior of sandwich panels having cork agglomerate core was investigated. In particular, the aim of this research work is to assess the shield function of unidirectional basalt and E-glass reinforced polymer on the aging and failure mechanism of the core when such class of material are destined to operate in hostile environments (e.g., marine environment). To do this, the manufactured sandwich panels were exposed up to 60 days to salt-fog environment, according to ASTM B 117 standard. Unaged and aged specimens were analyzed through three point bending tests after aging time of 10, 25 and 60 days. Digital Image Corr…
Quality evaluation of grapes for mechanical harvest using vis NIR spectroscopy
2019
Mechanical harvest of grapes is one of the operations that mostly influence the quality of the future wine. The shaking frequency of the harvesting machine is usually adjusted on the basis of the grape berry characteristics in order to limit grape juice production that is a potential cause of uncontrolled fermentations. These evaluations usually require time, personnel and laboratory analyses. The introduction of a vis NIR system to rapidly and reliably evaluate the berry properties in field before mechanical harvest could be a good alternative. The aim of this study was to evaluate the feasibility of applying vis NIR spectroscopy as a non-destructive technique on grapes cv. Syrah and Chard…
STUDY ON THE TUNNEL PASTEURIZER ON TABLE OLIVES PROCESSING
2015
The application of heat treatment is particularly important in maintaining the organoleptic characteristics of fermented agro-food products, which potential consumers perceive as reflecting the quality of these foodstuffs. However, heat treatments can be cause of deterioration of many quality parameters of agro-food products, including texture, intended as the consistency of the pulp. In this study 'Nocellara del Belice' table olives produced in 2010 and packaged in glass jars were subjected to pasteurization at industrial scale using a tunnel pasteurizer with a core temperature of 75°C for 8 min. The aim of the study was to mechanically evaluate the pulp texture evolution that contributes …
Dissesto idrogeologico: dall’EIMA i “cantieri del territorio”
2014
macchine per il territorio
Macchine agricole all’EIMA: il contoterzismo “driver” del mercato
2014
notizie dell'EIMA 2014