Come molti altri settori produttivi, anche l'agricoltura deve affrontare una crescente dipendenza energetica da elettricità, petrolio e gas naturale. Tuttavia, l'agricoltura può rispondere direttamente a tali richieste ricorrendo alle fonti di energia rinnovabili (FER), come il solare fotovoltaico (PV) e gli impianti biogas/biometano (BP). Questi sistemi sono stati fortemente incentivati in passato. Gli attuali sistemi d’incentivazione prevedono invece sussidi commisurati alle caratteristiche aziendali come stalle, fienili, disponibilità di biomasse, ecc. Per questi motivi, per quanto riguarda il settore FV, è necessario utilizzare modelli analitici affidabili per valutare l’orientamento e la tecnologia migliore, in particolare per generatori integrati architettonicamente. Per la produzione di biometano, gli impianti di piccole dimensioni risultano quelli maggiormente incentivati previa alimentazione con sottoprodotti agro-industriali. Tuttavia, le loro performance dipendono fortemente dalla tecnologia d’upgrading. Pertanto, le prospettive economiche offerte da questi sistemi RES sono legate alla scelta della tecnologia da impiegare e non più esclusivamente al semplice dimensionamento. Su questa base, l'obiettivo principale di questo lavoro è stato lo sviluppo di strumenti di supporto decisionali (DSSS) per l'ottimizzazione energetica d’impianti FV e BP. Un primo studio si è focalizzato sull’analisi prestazionale per singolo componente e globale d’impianti FV installati in un’azienda agricola. Inoltre, una procedura analitica di ottimizzazione dei parametri d’impianto è stata definita per massimizzare il rendimento elettrico di un generatore integrato architettonicamente rispetto ad un’installazione a terra. Attraverso una serie d’informazioni tecnico-economiche di tecnologie di upgrading, un secondo studio è stato condotto con l'obiettivo di sviluppare un DSS per valutare la marginalità sul reddito aziendale data dall’installazione on-farm di un impianto BP collegato alla rete del gas naturale. I risultati dei due studi hanno dimostrato come questi DSS possono essere utili strumenti per valutare preventivamente le diverse potenzialità offerte da impianti FV e BP in base alle caratteristiche di un’azienda agricola. / Like many other productive sectors, even agriculture must tackle an increasing energy dependency on electricity, petroleum and natural gas. Nevertheless, agriculture can directly respond to such request thanks to renewable energy systems (RES) like solar photovoltaic (PV) and biogas/biomethane (BP) plants. These systems have been strongly incentivized in the past. On the contrary, current incentive schemes provide feed-in-tariffs proportionate to farming characteristics as stables, barns, biomass availability, etc. For this reason, as regards the PV sector, it is required to use reliable analytical models for assessing the best orientation and technology, in particular for architecturally integrated generators. For the biomethane production, small-medium plants have stronger incentives in particular using agro-food by-products as feed. However, their performances are strongly dependent on biomethane upgrading technology. Thus, the economic prospective offered by these RES systems are substantially tied to technology choice optimization and no longer solely in simple sizing. On this basis, the main goal of this work is to develop Decision Support Tools (DSSs) for energy optimization both for PV and BP plants. A first study was focused on the analysis of PV plants installed in the same farm. The aim is to examine the impact each plant component has on the PV generator global efficiency and define an analytical procedure for technical parameters optimization in order to maximize the electric yield of an architectonically integrated plant compared to a ground-mounted one. Based on the economic and efficiency features of a biomethane upgrading technology set, a second study was carried out with the aim to design a DSS to assess enterprise-wide profit margins resulting from the on-farm BP plant installation linked to the natural gas grid. The results of the two studies have shown how these DSSs can be useful tools for choosing PV and BP technologies based on farm characteristics.

Negli ultimi anni le continue esigenze di mercato hanno spinto gli agricoltori a richiedere trattrici sempre più evolute e altamente specializzate al fine di limitare i costi e massimizzare le rese produttive. Per questo motivo i progettisti hanno dovuto sviluppare delle metodologie per definire con precisione il profilo di utilizzo delle macchine, al fine di ridefinire i test per la validazione finale dei componenti delle trattrici. Uno dei componenti più costosi è la trasmissione, in quanto è costituita da diversi automatismi e pertanto, in questa tesi, è stato descritto un piano sperimentale atto all’acquisizione di dati da trattrici utilizzate da clienti, con l’obiettivo di monitorare l’utilizzo delle trasmissioni. In una prima analisi sono state identificate relazioni statistiche del diverso utilizzo delle trasmissioni delle trattrici in funzione dell’area geografica di vendita e della potenza massima del motore. Sono state poi stimate le distribuzioni ed i parametri del tempo di neutro, delle gamme e retromarce, al fine di integrare le limitazioni riscontrate dalle analisi di correlazione cliente sulle trattrici. E’ stato riscontrato che la vita lavorativa di una trattrice è caratterizzata dal utilizzo del neutro e della gamma media per oltre il 75%. Non sono state evidenziate differenze significative tra i valori del 5° percentile della distribuzione del Neutro per l’intero campione rispetto a quelli calcolati per i gruppi, i quali sono stati formati in funzione dei fattori area geografica e intervalli di potenza massima motore. La gamma media, oltre ad essere la gamma più utilizzata, risulta essere influenzata dai fattori presi in esame, in particolare per le trattrici di potenza pari a A kW. / In the lasts years, the continuous demands of agricultural market, have prompted farmers of having more advanced and highly specialized tractors. This in order to limit the costs and maximize the working yields. Designers have, for the previous reasons, developed methods on the definition of machine usage profile, in order to re-define the final validation tests of tractor components. Considering that the most expensive components is the transmission, because it is constituted by various automatic functions, in this thesis it has been described an experimental acquisition data plan from tractors used by customers, to monitor the transmissions. First of all, there were identified statistical relations of the different tractor’s transmissions usage considering sale geographical areas and the maximum engine power. Therefore, there have been estimated distributions and parameters for neutral time, ranges and reverse gears, to supplement the limitations of customers correlation analysis about tractors. It has been verified that the tractor’s life time is characterized by the usage of the neutral and intermediate range for more than 75%. No significant differences were found between the values of the 5° percentile of the neutral gear distribution for the entire sample, compared to those calculated for the groups. These groups were formed considering the geographical area and maximum engine power ranges factors. The intermediate range, besides being the most used, is influenced by the considered factors, in particular for tractors with A kW of maximum engine power.

In food industry, quality assurance requires low cost methods for the rapid assessment of the parameters that affect product stability. Foodstuffs are complex in their structure, mainly composed by gaseous, liquid and solid phases which often coexist in the same product. Special attention is given to water, concerned as natural component of the major food product or as added ingredient of a production process. Particularly water is structurally present in the matrix and not completely available. In this way, water can be present in foodstuff in many different states: as water of crystallization, bound to protein or starch molecules, entrapped in biopolymer networks or adsorbed on solid surfaces of porous food particles. The traditional technique for the assessment of food quality give reliable information but are destructive, time consuming and unsuitable for on line application. The techniques proposed answer to the limited disposition of time and could be able to characterize the main compositional parameters. Dielectric interaction response is mainly related to water and could be useful not only to provide information on the total content but also on the degree of mobility of this ubiquitous molecule in different complex food matrix. In this way the proposal of this thesis is to answer at this need. Dielectric and electric tool can be used for the scope and led us to describe the complex food matrix and predict food characteristic. The thesis is structured in three main part, in the first one some theoretical tools are recalled to well assess the food parameter involved in the quality definition and the techniques able to reply at the problem emerged. The second part explains the research conducted and the experimental plans are illustrated in detail. Finally the last section is left for rapid method easily implementable in an industrial process.

La ricerca svolta ha voluto approfondire le possibilità offerte dai sistemi di allevamento dei vigneti a Doppia Cortina (GDC) e a Cordone Libero nei riguardi della meccanizzazione. La ricerca ha considerato gli interventi di potatura invernale, di gestione della chioma (spollonatura, cimatura, defogliazione e pettinatura della doppia cortina) e di vendemmia. Un’operazione particolarmente seguita è stata la potatura invernale realizzando differenti livelli di meccanizzazione. Tutti gli interventi sono stati eseguiti sia manualmente che meccanicamente, confrontando i tempi d’impiego, la qualità del lavoro svolto e gli impegni di manodopera. I risultati sono stati sintetizzati in una valutazione economica, ipotizzando differenti livelli di costo della manodopera impiegata, per ottenere giudizi di convenienza per i singoli interventi e per costruire una valutazione completa e più organica della linea di lavoro proposta. Nelle due forme d’allevamento la meccanizzazione della potatura invernale e della gestione della chioma hanno rispettato pienamente gli obbiettivi tecnici prefissati, dimostrando di essere un valido mezzo per ridurre tempi e costi di gestione. Per questi interventi l’acquisto delle macchine risulta conveniente anche per vigneti di piccola dimensione. Ancor più evidenti in queste due forme d’allevamento sono i vantaggi economici offerti dalla vendemmia meccanica, realizzata con pochi maltrattamenti e perdite di prodotto. La tendenza a meccanizzare integralmente gli interventi di gestione del ciclo colturale della vite, può essere nei prossimi anni un motivo di interesse e di scelta nella realizzazione di nuovi impianti con queste due forme di allevamento, che hanno dimostrato di essere un’espressione completa di sinergia tra macchina e pianta. / The research carried out has wanted to go into the possibility offered by the system of growing of double curtain vineyards (GDC) and in a free cordon referring to mechanization. The research has examined the operations of winter pruning, canopy management (removal of suckers, trimming, defoliation, and shoots positioning) and grape harvesting. The winter pruning was especially monitored through two different levels of mechanization. All the operations have been carried out, both manually and mechanically, comparing the times of working, the quality of the work effected and the engagement of manpower employed. The results have been synthesized under an economic valuation, supposing different levels of the cost of the employed manpower, in order to obtain to judge the suitability on the single interventions and to build a complete and more organic valuation of the proposed kind of work. In the two forms of growing, the mechanization of both the winter pruning and canopy management have respected completely the prefixed technical aims, showing to be a valid way in order both to reduce times and cost of management. For these interventions the purchase of machineries turns out to be suitable also for vineyards of small dimension. Even more evident in both these forms of growing are the economic advantages offered by the mechanized grape harvesting effected by few ill-treatments and wastes of product. The tendency to mechanize completely the interventions of management of the growing cycle of vineyards, can be in the next years both a reason of interest and of a choice in carrying out new installations with both these forms of growing that shown to be a complete expression of synergy between machinery and plant.

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In the context of “testing laboratory” one of the most important aspect to deal with is the measurement result. Whenever decisions are based on measurement results, it is important to have some indication of the quality of the results. In every area concerning with noise measurement many standards are available but without an expression of uncertainty, it is impossible to judge whether two results are in compliance or not. ISO/IEC 17025 is an international standard related with the competence of calibration and testing laboratories. It contains the requirements that testing and calibration laboratories have to meet if they wish to demonstrate that they operate to a quality system, are technically competent and are able to generate technically valid results. ISO/IEC 17025 deals specifically with the requirements for the competence of laboratories performing testing and calibration and for the reporting of the results, which may or may not contain opinions and interpretations of the results. The standard requires appropriate methods of analysis to be used for estimating uncertainty of measurement. In this point of view, for a testing laboratory performing sound power measurement according to specific ISO standards and European Directives, the measurement of uncertainties is the most important factor to deal with. Sound power level measurement, according to ISO 3744:1994 , performed with a limited number of microphones distributed over a surface enveloping a source is affected by a certain systematic error and a related standard deviation. Making a comparison of measurement carried out with different microphone arrays is difficult because results are affected by systematic errors and standard deviation that are peculiarities of the number of microphones disposed on the surface, their spatial position and the complexity of the sound field. A statistical approach could give an overview of the difference between sound power level evaluated with different microphone arrays and an evaluation of errors that afflict this kind of measurement. Despite the classical approach that tend to follow the ISO GUM this thesis present a different point of view of the problem related to the comparison of result obtained from different microphone arrays.

Today the design of hydraulic and lubrication circuits is becoming more and more important. The aim of this study is to develop a methodology for the design of the lubrication circuit of an agricultural tractor. In this paper the lubrication circuit of a continuously variable transmission is analysed. Several lines of the circuit are considered and in particular the lubrication of gears is discussed. The worst possible working condition which corresponds to the highest power dissipation for each part of the transmission is determined. The model of the lubrication circuit is developed with two different software simulations (Automation Studio & Amesim). In order to check the reliability of the simulation models and to characterise the lubrication circuit, experimental tests are performed. The comparison between the values of pressure drops obtained by the models and by the experimental test, demonstrates that it is possible to use these programs for the set up of a simple model of the lubrication circuit. The calculation of oil flows necessary for a force-fed lubrication of the gears, the simulation of the circuit by commercial software, and the validation of the circuit design allow to set up a preliminary equilibrium among the pipes and a proper flow rate distribution. Optimising the circuit design in the initial phase of the project is very important. The experimental adjustment of the circuit, which is often difficult, can be simplified; time and cost production can be reduced.

In order to improve the animal welfare, the Council Directive 1999/74/EC (defining minimum standards for the welfare of laying hens) will ban conventional cage systems since 2012, in favour of enriched cages or floor systems. As a consequence an increased risk of bacterial contamination of eggshell is expected (EFSA, 2005). Furthermore egg-associated salmonellosis is an important public health problem throughout the world (Roberts et al., 1994). In this regard the introduction of efficient measures to reduce eggshell contamination by S. Enteritidis or other bacterial pathogens, and thus to prevent any potential or additional food safety risk for Human health, may be envisaged. The hot air pasteurization can be a viable alternative for the decontamination of the surface of the egg shell. Few studies have been performed on the decontamination power of this technique on table eggs (Hou et al, 1996; James et al., 2002). The aim of this study was to develop innovative techniques to remove surface contamination of shell eggs by hot air under natural or forced convection. Initially two simplified finite element models describing the thermal interaction between the air and egg were developed, respectively for the natural and forced convection. The numerical models were validated using an egg simulant equipped by type-K thermocouple (Chromel/Alumel). Once validated, the models allowed the selection of a thermal cycle with an inner temperature always lower than 55°C. Subsequently a specific apparatus composed by two hot air generators, one cold air generator and rolling cylinder support, was built to physically condition the eggs. The decontamination power of the thermal treatments was evaluated on shell eggs experimentally inoculated with either Salmonella Enteritidis, Escherichia coli, Listeria monocytogenes and on shell eggs containing only the indigenous microflora. The applicability of treatments was further evaluated by comparing quality traits of treated and not treated eggs immediately after the treatment and after 28 days of storage at 20°C. The results showed that the treatment characterized by two shots of hot air at 350°C for 8 sec, spaced by a cooling interval of 32 (forced convection), reduce the bacterial population of more than 90% (Salmonella enteritidis and Listeria monocytogenes). No statistically significant results were obtained comparing E. coli treated and not treated eggs as well as indigenous microflora treated and not treated eggs. A reduction of 2.6 log was observed on Salmonella enteritidis load of eggs immediately after the treatment in oven at 200°C for 200 minutes (natural convection). Furthermore no detrimental effects on quality traits of treated eggs were recorded. These results support the hot air techniques for the surface decontamination of table eggs as an effective industrial process.