Search results for " meccanica"
showing 10 items of 819 documents
A system for the real-time geo-referenced measurement of soil parameters
2011
The aim of this research is to develop a system for accurately measuring in real-time, collecting and processing a high amount of geo-referenced data of soil physical-mechanical parameters, e.g. cone penetrometer resistance, index of soil compaction, and draft force. The system for measuring the soil cone penetrometer resistance is comprised of a load cell, connected to a rod, ending with a cone, and is mounted on a frame, fixed to the front part of a tractor. The system for measuring the draft force required to till the soil is comprised of a load cell, mounted on the hitch hook of a tool carrier, towed by the tractor. Moreover, in order to test the usefulness of the system with different …
Optimal manufacturing and mechanical characterization of high performance biocomposites reinforced by sisal fibers
2018
Abstract The increasing interest about eco-sustainable materials in the industrial production (automotive, civil construction, packaging), has led to the increase of the research works dealing with biocomposites. However, until now the most attention has been devoted to the development of short fiber biocomposites for non-structural applications, whereas only a few works have considered high performance biocomposites for structural applications. Consequently, the development of structural biocomposites from robust natural fibers, as sisal fibers, is a result expected from the scientific community, but not yet achieved. In order to give a contribution to the implementation of high performanc…
EFFETTO DELLA PRESSURIZZAZIONE DEI FORI E DELL’INDENTAZIONE ANULARE SULLA VITA A FATICA DI PROVINI IN LEGA DI ALLUMINIO
2011
Nel lavoro è investigato il comportamento a fatica di lastre forate in lega di alluminio. In particolare è valutata l‟influenza combinata dell‟espansione a freddo dei fori e dell‟indentazione sul miglioramento della vita a fatica. A tal fine sono state condotte diverse prove di fatica aventi lo scopo di valutare il numero di cicli a rottura e la conseguente curva di Wöhler. I risultati sperimentali sono stati confrontati con quelli ottenuti senza la realizzazione di alcun processo di espansione e di espansione-indentazione. Lo studio ha permesso di concludere che il processo di espansione ed indentazione anulare determina un ritardo nella nascita della cricca e della conseguente rottura a f…
AN INNOVATIVE SYSTEM FOR VINEYARD MANAGEMENT IN SICILY
2010
The aim of this study was to monitor the micro-climate of the grapevine in order to detect the adversities of the spring period (especially April and May), while reducing the operating costs of the vineyard, and increasing the overall quality of grapes. For this purpose a Wireless Sensor Network (WSN) was used. Furthermore, a comparison was performed between data measured by the wireless sensors and data provided by the fixed meteorological station of the Regione Siciliana (SIAS).
Generation of narrowband antisymmetric lamb waves using a formed laser source in the ablative regime
2007
A formed laser source, using a four-element lenticular array, is used in the ablative regime to generate select, narrowband, acoustic plate waves. The arrangement of the array produces acoustical signals that have frequencies compatible with the response of the broadband capacitive air-coupled transducer used in this study. A simplified concept is presented to explain the effect of a line array source on the frequency content of acoustic waves. The analytical model for a point pulse surface displacement is derived from the point load solution to Lamb's problem. The point pulse displacement elements of a line array source are summed mathematically, taking into account all applicable propagat…
L'utilizzo della tecnologia RFId per la valorizzazione dei territori rurali
2014
tecnologie innovative RFId al servizio dei territori rurali
Plants for Environmental Protection
2023
Plants for environmental protection are Anaerobic Digestion plants for converting biomass as Renewable Energy Source (RES), i.e. biowaste, agricultural feedstock, livestock effluents (manure and slurry) and food industry by-products, into biogas, i.e. bioenergy, as well as digestate, i.e. biofertiliser. In turn, biogas can be converted into electrical and thermal energy or can be used for extracting biomethane, i.e. biofuel, or can be injected in the natural gas grid. Moreover, digestate can be divided into solid and liquid fractions, that can be used for fertilisation or fertirrigation, respectively, sometimes after aerobic composting.
Integration of green roofs&walls in urban areas
2020
Growing urbanization is associated with the emergence of environmental problems, such as the reduction of natural resources, the atmosphere pollution and the increase of the heat islands phenomenon in cities. The integration of vegetation in the urban areas, through the creation of green hanging systems, represents a possible solution to improve the energy sustainability of buildings, to combat meteoric excesses, to improve stormwater management and to reduce pollutant levels. These energy and environmental benefits are related to the properties of evapotranspiration, shading and thermal insulation of the vegetation. The work reports the results of the main studies concerning the use of han…
Case Study of Potential Production of Renewable Energy Sources (RES) from Livestock Wastes in Mediterranean Islands
2017
The aim of this work is to evaluate the potential production of Renewable Energy Sources (RES) from livestock wastes that are commonly found on Mediterranean islands, by using the island of Malta as a case study. Organic wastes in the form of livestock manure and slurry, as well as other by-products originating from the food transformation industry in the making of alcoholic beverages and the processing of olives, tomatoes and other streams, if mixed in such a way to achieve a correct C/N ratio, can be subjected to anaerobic co-digestion for the production of biogas and digestate. Biogas can be further transformed into biomethane, a fuel that can be used to power surface transportation and …
INFLUENCE OF UNCERTAINTIES ON ROTATING FLEXIBLE SHAFT SUSPENDED BY 4-AXIS RADIAL ACTIVE MAGNETIC BEARINGS µ-SYNTHESIS AND LOOP-SHAPING-DESIGN
2012
This paper shows a comparison about dynamic behavior of a rotating shaft when it is suspended by 4-axis radial active magnetic bearing system. The active magnetic suspension is obtained by two different controllers which realize the robust stability and robust performance. The control systems used are µ-synthesis and loop shaping design procedure. Each of these controllers is characterized by fourinput and four output signals and the introduction of uncertainties on displacement gain and current gain is justified by the simple fact that during the time the component which constitutes these gains can be subjected to torn and worn which can lead the entire system to instability phenomena. The…