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Progettazione, realizzazione e prime verifiche di campo di un sistema di monitoraggio della carpocapsa (Cydia pomonella L.)Studhalter, Marco <1981> 31 May 2010 (has links)
No description available.
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Tecnologie di confezionamento delle sementiCapacci, Enrico <1978> 31 May 2010 (has links)
No description available.
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Applicazioni industriali e di ricerca della spettroscopia NIR per la valutazione di indici qualitativi di prodotti alimentariSilaghi, Florina Aurelia <1983> 12 May 2011 (has links)
In the present work qualitative aspects of products that fall outside the classic Italian of food production view will be investigated, except for the apricot, a fruit, however, less studied by the methods considered here.
The development of computer systems and the advanced software systems dedicated for statistical processing of data, has permitted the application of advanced technologies including the analysis of niche products. The near-infrared spectroscopic analysis was applied to the chemical industry for over twenty years and, subsequently, was applied in food industry with great success for non-destructive in line and off-line analysis.
The work that will be presented below range from the use of spectroscopy for the determination of some rheological indices of ice cream applications to the characterization of the main quality indices of apricots, fresh dates, determination of the production areas of pistachio.
Next to the spectroscopy will be illustrated different methods of multivariate analysis for spectra interpretation or for the construction of qualitative models of estimation.
The thesis is divided into four separate studies that consider the same number of products. Each one of it is introduced by its own premise and ended with its own bibliography. This studies are preceded by a general discussion on the state of art and the basics of NIR spectroscopy.
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Non destructive methods in the automation of the dates quality evaluationShakhs Tavakolian, Mohammad Sadegh <1983> 12 May 2011 (has links)
No description available.
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Meccanizzazione delle fasi di raccolta delle biomasse dedicate e residuali. Utilizzo di GPS e altri componenti elettronici per il rilevamento automatico dei datiZucchelli, Matteo <1982> 12 May 2011 (has links)
No description available.
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Prove accelerate per la verifica strutturale di trattrici agricole / Accelerated structural tests on agricultural tractorsMattetti, Michele <1982> 11 May 2012 (has links)
The needs of customers to improve machinery in recent years have driven tractor manufacturers to reduce product life and development costs. The most significant efforts have concentrated on the attempt to decrease the costs of the experimental testing sector. The validation of the tractor prototypes are presently performed with a replication of a particularly unfavourable condition a defined number of times. These laboratory tests do not always faithfully reproduce the real use of the tractor. Therefore, field tests are also carried out to evaluate the prototype during real use, but it is difficult to perform such tests for a period of time long enough to reproduce tractor life usage. In this context, accelerated tests have been introduced in the automotive sector, producing a certain damage to the structure in a reduced amount of time. The goal of this paper is to define a methodology for the realization of accelerated structural tests on a tractor, through the reproduction of real customer tractor usage. A market analysis was performed on a 80 kW power tractor and a series of measures were then taken to simulate the real use of the tractor. Subsequently, the rainflow matrixes of the signals were extrapolated and used to estimate the tractor loadings for 10 years of tractor life. Finally these loadings were reproduced on testing grounds with special road pavements. The results obtained highlight the possibility of reproducing field loadings during road driving on proving grounds (PGs), but the use of two field operations is also necessary. The global acceleration factor obtained in this first step of the methodology is equal to three.
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Analisi dei cantieri di Cippatura in merito ad aspetti operativi e di salvaguardia degli operatori / Analysing Wood Chipping Operations for Technical ad Operator Health PerformanceMagagnotti, Natascia <1971> 11 May 2012 (has links)
La cippatura è un processo produttivo fondamentale nella trasformazione della materia prima forestale in biomassa combustibile che coinvolgerà un numero sempre più crescente di operatori.
Scopo dello studio è stato quantificare la produttività e il consumo di combustibile in 16 cantieri di cippatura e determinare i livelli di esposizione alla polvere di legno degli addetti alla cippatura, in funzione di condizioni operative differenti.
Sono state identificate due tipologie di cantiere: uno industriale, con cippatrici di grossa taglia (300-400kW) dotate di cabina, e uno semi-industriale con cippatrici di piccola-media taglia (100-150kW) prive di cabina.
In tutti i cantieri sono stati misurati i tempi di lavoro, i consumi di combustibile, l’esposizione alla polvere di legno e sono stati raccolti dei campioni di cippato per l’analisi qualitativa.
Il cantiere industriale ha raggiunto una produttività media oraria di 25 Mg tal quali, ed è risultato 5 volte più produttivo di quello semi-industriale, che ha raggiunto una produttività media oraria di 5 Mg.
Ipotizzando un utilizzo massimo annuo di 1500 ore, il cantiere semi-industriale raggiunge una produzione annua di 7.410 Mg, mentre quello industriale di 37.605 Mg.
Il consumo specifico di gasolio (L per Mg di cippato) è risultato molto minore per il cantiere industriale, che consuma in media quasi la metà di quello semi-industriale.
Riguardo all’esposizione degli operatori alla polvere di legno, tutti i campioni hanno riportato valori di esposizione inferiori a 5 mg/m3 (limite di legge previsto dal D.Lgs. 81/08).
Nei cantieri semi-industriali il valore medio di esposizione è risultato di 1,35 mg/m3, con un valore massimo di 3,66 mg/m3. Nei cantieri industriali si è riscontrato che la cabina riduce drasticamente l’esposizione alle polveri di legno. I valori medi misurati all’esterno della cabina sono stati di 0,90 mg/m3 mentre quelli all’interno della cabina sono risultati pari a 0,20 mg/m3. / This study examined 16 commercial chipping operations in order to determine: productivity, fuel consumption, cost and exposure to wood dust Operations were divided into industrial and semi-industrial, the former based on powerful chippers (300-400 kW) fitted with an enclosed cab, and the latter on smaller machines (100-150 kW) without enclosed cab.
Field data was collected for time consumption, mass output, fuel use and exposure to wood dust. Chip samples were taken from all operations in order to determine moisture content and particle size distribution.
During the tests, chipper operators wore special wood dust samplers. When the operators sat inside a cab, wood dust samplers were also placed outside the cab in order to determine the dust abatement benefit offered by the enclosed cab.
As an average, industrial operations reached a productivity of 25 Mg fresh chips per hour, whereas semi-industrial operations produced only one fifth of this quantity (i.e. 5 Mg/h). Assuming 1500 hours as the maximum annual usage, industrial operations offer an annual production in excess of 37.000 Mg, whereas semi-industrial operations barely exceed 7.000 Mg. Cost-wise, semi-industrial operations are preferable to industrial operations only if the annual production is below 3.000 Mg. Specific fuel consumption (L per Mg of chips) is much lower for industrial operations, compared to semi-industrial operations.
Concerning exposure to wood dust, all the sampled operations were within the 5 mg/m3 legal limit. Exposure was higher in semi-industrial operations, with average and maximum values of 1,35 and 3,66 mg/m3, respectively. Exposure was lower in industrial operations, where the recorded average values were 0,90 and 0,20 mg/m3 outside and inside the cab, respectively. If future legislation will reduce the maximum allowed exposure to 1 mg/m3, then semi-industrial operators may need to renounce manual chipper feeding and bring their operators inside the cab of a boom loader.
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Valutazione della qualità ed autenticità di prodotti oleari e lattiero caseari mediante metodi fisici di analisi accoppiati a tecniche statistiche multivariate / Evaluation of the quality and authenticity of oil and dairy products by physical analysis coupled with multivariate statistical techniquesCerretani, Lorenzo <1976> 09 May 2013 (has links)
Questa tesi descrive alcuni studi di messa a punto di metodi di analisi fisici accoppiati con tecniche statistiche multivariate per valutare la qualità e l’autenticità di oli vegetali e prodotti caseari.
L’applicazione di strumenti fisici permette di abbattere i costi ed i tempi necessari per le analisi classiche ed allo stesso tempo può fornire un insieme diverso di informazioni che possono riguardare tanto la qualità come l’autenticità di prodotti.
Per il buon funzionamento di tali metodi è necessaria la costruzione di modelli statistici robusti che utilizzino set di dati correttamente raccolti e rappresentativi del campo di applicazione.
In questo lavoro di tesi sono stati analizzati oli vegetali e alcune tipologie di formaggi (in particolare pecorini per due lavori di ricerca e Parmigiano-Reggiano per un altro).
Sono stati utilizzati diversi strumenti di analisi (metodi fisici), in particolare la spettroscopia, l’analisi termica differenziale, il naso elettronico, oltre a metodiche separative tradizionali.
I dati ottenuti dalle analisi sono stati trattati mediante diverse tecniche statistiche, soprattutto: minimi quadrati parziali; regressione lineare multipla ed analisi discriminante lineare. / The thesis describes some studies of setting-up of physical methods coupled with multivariate statistical techniques for the evaluation of the quality and authenticity of oil and dairy products. The application of physical techniques allows to reduce costs and time required for the classical analysis and at the same time may provide a different set of information which can relate to the quality as the authenticity of products.
For the correct functioning of these methods it is necessary to build statistical models that use robust set of data collected and properly representative of the scope. In this thesis vegetable oils and some types of cheese were analyzed.
In this thesis were used different analytical tools (physical methods), in particular spectroscopy, differential scanning calorimetry, electronic nose, in addition to traditional chromatographic methods.
The data obtained from the analysis were treated by different statistical techniques, especially: partial least squares modelling, multiple linear regression and linear discriminant analysis.
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Applications of infrared thermography in the food industryCuibus, Lucian <1982> 09 May 2013 (has links)
In the last 20-30 years, the implementation of new technologies from the research centres to the food industry process was very fast. The infrared thermography is a tool used in many fields, including agriculture and food science technology, because of it's important qualities like non-destructive method, it is fast, it is accurate, it is repeatable and economical. Almost all the industrial food processors have to use the thermal process to obtain an optimal product respecting the quality and safety standards. The control of temperature of food products during the production, transportation, storage and sales is an essential process in the food industry network. This tool can minimize the human error during the control of heat operation, and reduce the costs with personal.
In this thesis the application of infrared thermography (IRT) was studies for different products that need a thermal process during the food processing. The background of thermography was presented, and also some of its applications in food industry, with the benefits and limits of applicability. The measurement of the temperature of the egg shell during the heat treatment in natural convection and with hot-air treatment was compared with the calculated temperatures obtained by a simplified finite element model made in the past. The complete process shown a good results between calculated and observed temperatures and we can say that this technique can be useful to control the heat treatments for decontamination of egg using the infrared thermography. Other important application of IRT was to determine the evolution of emissivity of potato raw during the freezing process and the control non-destructive control of this process. We can conclude that the IRT can represent a real option for the control of thermal process from the food industry, but more researches on various products are necessary.
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Analisi dell’influenza dei moti rigidi di una trattrice agricola sulle vibrazioni a corpo intero trasmesse all’operatore / Agricultural tractor rigid motion effects analysis on whole body vibrationsBadodi, Matteo <1981> 09 May 2013 (has links)
L’esposizione degli operatori in campo agricolo alle vibrazioni trasmesse al corpo intero, produce effetti dannosi alla salute nel breve e nel lungo termine. Le vibrazioni che si generano sulle trattrici agricole hanno una elevata intensità e una bassa frequenza. Le componenti orizzontali, amplificate dalla posizione elevata della postazione di guida dall’asse di rollio, presentano maggiori criticità per quanto riguarda i sistemi di smorzamento rispetto alle componenti verticali. Queste caratteristiche rendono difficoltosa la progettazione dei sistemi dedicati alla riduzione del livello vibrazionale per questa categoria di macchine agricole. Nonostante l’installazione di diversi sistemi di smorzamento, il livello di vibrazioni a cui è sottoposto l’operatore può superare, in diverse condizioni di impiego, i livelli massimi imposti dalla legge per la salvaguardia della salute. L’obiettivo di questo lavoro è quello di valutare l’influenza dei moti rigidi di una trattrice (beccheggio, rollio e saltellamento) dotata di sospensione assale anteriore, sospensione cabina e sospensione sedile, sul livello vibrazionale trasmesso all’operatore.E’ stata pertanto strumenta una trattrice con accelerometri e inclinometri installati su telaio, cabina e sedile e utilizzata in diverse condizioni di lavoro in campo e di trasporto su strada. Dall’analisi delle prove effettuate emerge che durante il trasporto su strada è predominante l’accelerazione longitudinale, a causa dell’elevata influenza del beccheggio. La sospensione riduce notevolmente il moto rigido di beccheggio mentre l’effetto della sospensione della cabina è quello di incrementare, in ogni condizione di lavoro, il livello di accelerazione trasmesso dal telaio della macchina. / The vibrations transmitted to the driver are dangerous and can cause temporary or permanent injuries. Tractors are characterized by vibrations with high intensity and low frequency. The most critical directions are represented by the horizontal ones because of the high distance from the seat and the tractor rolling axis with respect to the vertical direction. That increase the difficulties in the design of solutions able to reduce the vibration transmitted to the driver. Despite the fitting of different damping systems, the level of vibration to which the operator is subjected, could be over the maximum levels defined into health safe law in different working conditions. The goal of this study is the evaluation of the influence of tractor rigid motions (pitch, roll and bounce) on the vibration level transmitted to the operator and their influence offront axle suspension, cab suspension and suspension seat. To reach this goal, devices as inclinometers and accelerometers were installed on a tractor chassis, cab and seat. The tractor in different working conditions as field and road transport was used. The analysis of the test data shows that the longitudinal acceleration is predominant during road transport, due to the influence of pitch motion. The front axle suspension greatly reduces the pitch while the cab suspension, increases the acceleration level transmitted from the machine frame in every working condition.
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