L'articolo descrive un banco di prova automatico progettato e realizzato con lo scopo di caratterizzare, in modo semplice e ripeti bile, il comportamento degli elastici IJtilizzati nei fucili per lo pesca subacquea. Questi elastici, una volta allungati, grazie alla loro notevole capacità di contrarsi rapidamente, vengono adottati come propulsori del dardo di questi specifici attrezzi da pesco. Il sistemo realizzato consente lo valutazione del loro comportamento rìcavandone la curvo sforzo-deformazione (o-e) 01 variare di alcuni parametri significativi quali l'elongazione percentuale e il tempo trascorso fra lo fase di allungamento e il successivo scarico a cui il provino è sottoposto.

In questo articolo è illustrato un nuovo metodo per la stima del contenuto spettrale di segnali affetti da fluttuazioni di ampiezza e frequenza. Il metodo permette di analizzare i segnali della rete elettrica dove la frequenza e l’ampiezza della componente fondamentale possono variare nel tempo.

In questa memoria è illustrato un metodo per la stima del contenuto spettrale di segnali modulati in frequenza. Il metodo è stato sviluppato per l’analisi di segnali della rete elettrica dove, come ben noto, la frequenza e la fase della componente fondamentale possono cambiare lentamente nel tempo. Esso si basa su una scelta differente delle funzioni armoniche rispetto a quelle generalmente utilizzate come base nel calcolo della Trasformata Discreta di Fourier (DFT). In particolare il metodo ammette una variazione nel tempo della frequenza di tali funzioni, calcolata sulla base di un rivelatore di fase istantanea. L’ortogonalità della base è preservata utilizzando un cambio del sistema temporale di riferimento. La teoria è stata sviluppata in tempo continuo e successivamente implementata in tempo discreto e verificata con simulazioni numeriche.

L’articolo descrive un banco di prova automatico progettato e realizzato con lo scopo di caratterizzare, in modo semplice, efficace e ripetibile il comportamento degli elastici utilizzati nei fucili per la pesca subacquea. Questi elastici, una volta allungati, grazie alla loro capacità di rilasciare rapidamente l’energia accumulata, sono oggi adottati come propulsori del dardo di questi specifici attrezzi da pesca. Il sistema realizzato consente la valutazione del loro comportamento ricavandone la curva sforzo-deformazione (σ-ε) al variare di alcuni parametri significativi quali l’elongazione massima percentuale e il tempo trascorso fra il termine della fase di allungamento e il momento del rilascio; i cicli di prova sono gestiti da un sofisticato circuito a microcontrollore appositamente progettato, gestito in remoto da uno strumento virtuale sviluppato in LabVIEW.

This paper describes the realization of an automated system for rubber characterization in spearfishing applications. These materials, once lengthened, thanks to their ability to shrink very quickly, are used as dart propellers in fishing spears. The system permits the evaluation of the rubber behavior getting its stress vs. strain curve, allowing also the study of the effects of one or more parameters change like the maximum percentage elongation and the time elapsed between the stretching and shrinking phases at which the device under test is subj

In this paper a prototype of an energy monitoring device based on an open source concept is presented. This architecture assures several advantages with respect to traditional energy meters, such as easy development of new applications making cost- and time-effective the migration to future smart grid infrastructures and simple adjustments to change in the relevant standards. The open source philosophy has been adopted designing the software components in order to make all features easily customizable by the user. In this work the characterization of the acquisition channels using measurement data obtained stimulating them with signals generated using a high-accuracy waveform generation module is presented.

The purpose of this work is to analyze and to quantify the contributions of measurement uncertainty in the human exposure to vibrations. Typically, the high-level vibrations exposure in workplace can cause the onset of pathologies affecting musculoskeletal, vascular and neurological systems. Regulations and Standards lay down the assessment of the health risks arising from vibrations by using specific instruments and a proper measurement procedure. This paper proposes a methodology for the uncertainty evaluation of exposure to hand-arm and whole-body vibrations; as a main contribution, the uncertainty analysis of daily exposure hand-arm vibrations and whole-body vibrations is provided in order to estimate the exposition vibrations and to reduce the risks of the worker. This activity was developed in collaboration with Military Navy Arsenal in Taranto (South Italy), which is active all along in the protection of health and the safety in the workplace

The purpose of this work is twofold: first to investigate the accuracy of Photo-Voltaic (PV) modeling under non-standard test conditions (STCs), and then to estimate the inaccuracies on maximum power prediction for different PV technologies; this is achieved through the comparison between predicted and measured data under a variety of operating conditions. The developed technique is based on the identification of the modules parameters of the double-diode equivalent circuit. The model has been validated by experimental data taken on five different ?2 kWp plants of the PV LABoratory (PV-LAB), with different interconnection schemes, and it predicts the power production for mono and poly crystalline Silicon (m-Si and p-Si) plants, while the prediction for CIGS and CdTe PV plants appears less accurate. Results of this comparison are then used to analyze the impact of prediction inaccuracy under real operating conditions

The purpose of this work is to evaluate how the choice of mother wavelet function affects ultrasound image denoising. The paper presents a detailed analysis of the properties of each wavelet family highlighting their properties and limitations in ultrasound image filtering applications. The study has been carried out using controlled noise-variance ultrasound images simulated by Field II program in order to compare the effectiveness of filtering. Medical image quality for each wavelet function has been evaluated using two different metrics: the classical peak signal-to-noise ratio and the edges preservation in the filtered image. Significant remarks have been found out from the analysis providing valuable information to obtain best image for ultrasound exams. Finally real high-quality ultrasound images have been processed by the proposed method to validate obtained results.

This paper describes the realization of an automated system for rubber characterization in spearfishing applications. These materials, once lengthened, thanks to their ability to shrink very quickly, are used as dart propellers in fishing spears. The system permits the evaluation of the rubber behavior getting its stress vs. strain curve, allowing also the study of the effects of one or more parameters change like the maximum percentage elongation and the time elapsed between the stretching and shrinking phases at which the device under test is subject.

Smart grids and Smart Meters (SM) are considered two key factors to build greener and cheaper ways of managing energy. Generally speaking, smart metering is the major task toward the implementation of the paradigm of the SGs. New players have appeared and existing players are adapting their business model to achieve competitiveness and security of supply in a context of growing environmental pressure.

Years of unbridled growth, with no respect for rules, in many cases due to the absence of effective monitoring tools, have produced in some localized areas of Italy the so-called eco-monsters, to which a state of widespread pollution due to multiple anthropogenic causes must be added. In this paper a review of current and emergent available techniques, materials and tools for water monitoring is presented; new solutions and designing criteria meeting low-cost specification are also proposed.

This paper presents the application of a measurement procedure for improving data acquisition for the characterization of soft magnetic ferrites. The approach is based on a voltamperometric technique and is aimed at better measure minor asymmetric cycles improving the quality and resolution of measurement data. Physical and mathematical conditions require the use of current and voltage signals with very different dynamic range since the major loop has to be traced together to the minor cycles. In such a way, the possibility to get the signal via two channels with different configuration is analyzed and discussed. Preliminary results are reported in the paper together to some preliminary concerns relevant to the metrological characterization of the method.

Il problema fondamentale dell’energia ottenuta da fonti rinnovabili è che esse non sono sorgenti prevedibili per cui il gestore della rete riesce con molta difficoltà ad accumulare o smaltire grandi quantità di energia in eccesso così come non può affidarsi a queste fonti per pianificare i flussi di potenza nelle ore più critiche della giornata. Oggi si punta pertanto a sviluppare tecnologie che consentano di valutare in tempo praticamente reale la quantità e dal qualità [1] dell’energia prodotta da fonti energetiche attive in una data area e in certe condizioni ambientali e di determinarne il costo. Uno dei problemi connessi alla liberalizzazione del mercato elettrico è quello della autovalutazione, dei disturbi che ogni singolo produttore e utilizzatore immette in rete [2] al fine di minimizzarli. Con queste premesse, risulta vitale per il gestore [3] e spesso anche per l’utente identificare le eventuali fonti di disturbo [4] e attuare le giuste misure per compensarli; parimenti, risulta fondamentale per il produttore risalire a eventuali sorgenti di guasto nel suo impianto e, ricostruire lo storico della sua produzione, così da identificare le cause di problemi ricorrenti e intervenire tempestivamente. In questo modo si possono ridurre i costi di manutenzione e gestione aumentando l’affidabilità globale dell’impianto e riducendo il tempo necessaria al rientro dell’investimento iniziale.

This paper presents a novel parametric thresholding procedure to reduce the effect of speckle noise in ultrasound (US) medical images. The method comprises the use of an adaptive data-driven exponential operator that operates on wavelet coefficients of the US image to suppress undesired effects of disturbances, preserving signal details. The obtained results demonstrate that the proposed denoising method increases the medical image quality and, therefore, it can be a useful tool in medical diagnosis.

Recently, many complex medical exams require correlating the information from magnetic resonance (MR) and computed tomography (CT) images in order to obtain a more accurate diagnostics. This is rather complex when the images under test have very different noise level. In this paper, a technique to compare the quality of the CT and MR images is introduced. The proposed technique is useful to assess the effect of different noise distribution on medical images and to equalize the examinations produced by different imagining technologies in terms of clearness of images and sharpness of contours. The authors, after examining the statistical properties of the noise affecting CT and MR images, analyze its effect on final image quality. Then, a methodology to compare the mean square errors relevant to CT and MR images is proposed. The study was carried out using 148 images obtained from patients under neuropsychological test. The experimental tests have been performed by corrupting the original data with different noise levels.

The main purpose of this work is the assessment of quality performance of medical imaging systems by using objective image quality tests. To this aim, the influence of radiographic parameters has been investigated in order to reduce radiation dose to patients by assuring a good quality of the images.

The paper presents a novel denoising method for ultrasound medical images, whose quality is degraded by the peculiar phenomenon of speckle noise. The method is constructed step-by-step on the basis of recent research on the topic, and consists in Gaussian filtering of proper wavelet coefficients of the image, corresponding to vertical and diagonal details. A comparison with other filtering techniques for ultrasound imaging, i.e. Wiener and median filter, is presented. The obtained results, combined with those reported in independent research, demonstrate that the proposed denoising scheme has very good performance and is very promising for actual medical application.

La ricerca si propone la realizzazione di un sistema integrato di gestione informatizzata di cartelle cliniche in ambito nefrologico. Tale processo mira a garantire un’assistenza nefrologica completa dal punto di vista diagnostico assicurando l’erogazione di un servizio molto efficiente con riflessi positivi sulla vita dei pazienti. Esso dovrebbe consentire l’aggiornamento costante della situazione dei malati e l’immediata disponibilità di dati determinando vantaggi non solo a fini diagnostici, ma anche in termini di risparmio di risorse umane ed economiche. La successiva condivisione di dati e cartelle sul web consentirà ai diversi centri nefrologici nazionali (50 in tutto) analisi epidemiologiche nonché l’avvio di studi clinici osservazionali di tipo “outcome research” che rappresentano il punto di partenza per l’impostazione di trials clinici di tipo controllato e randomizzato su larga scala.

L’inaging medico è oggi la tecnica più utilizzata per svolgere indagini diagnostiche in aree interne di organismi viventi e per eseguire, in alcuni casi, anche azioni terapeutiche. Tra le diverse tecnologie oggi disponibili la tomografia computerizzata (CT) e la risonanza magnetica (MR) sono le tecniche di indagini più utilizzate quando è richiesta una elevata qualità delle immagini. Sebbene normalmente le due tecniche vengono utilizzate separatamente, a causa della complessità di alcuni esami diagnostici, risulta utile e a volte necessario effettuare esami congiunti che confrontino i risultati ottenuti con CT e MR. In tal caso occorre effettuare un processo di “equalizzazione” delle immagini che consenta uguagliare le qualità degli esami messi a confronto. Inoltre, un metodo di confronto della qualità delle immagini, può risultate utile nel campo delle tecniche di filtraggio del rumore applicate a metodologie di imaging medico differenti. Infatti per confrontare le prestazioni di un filtro applicato a tecniche diagnostiche diverse, occorre partire da immagini di riferimento caratterizzate dallo stesso indice di qualità.

This paper deals with the uncertainty analysis of parameters estimated during long-term monitoring of photovoltaic plants. A specifically developed data-acquisition system is briefly described, which has been conceived to be easily calibrated and, if necessary, adjusted to compensate for measuring-chain drifts, in order to assure the traceability of the estimated parameters. The measurement capabilities of the acquisition system are reported in terms of measured quantities and expected uncertainty. Results that refer to a three-year monitoring of ten photovoltaic plants based on different technologies and architectures are reported. The obtained uncertainty is suitable to distinguish the behavior of the different plants, thus allowing a preliminary comparison to be performed among technologies and architectures. Experimental results highlight an important difference between crystalline silicon devices and thin film technologies in regards to degradation.

In this paper we analyze how static errors of Analog-to-Digital converters (ADCs) can influence the measurement of magnetic accommodation in soft ferrite core. In a first analysis, the discussion is carried out through a series of simulated ADC INLs applied to simulated signals and experimental data. Possible impacts of the integral nonlinearity (INL) on the reconstruction of the B H trajectory are shown. In a second phase, a real ADC INL is considered to better quantify the impact of real ADC errors on the measurements. An easy to implement procedure based on physical symmetry property of the material is presented and adopted to reduce the INL effect on magnetic accommodation measurements. Finally, a comparison between the proposed approach and a mid-point linearization compensation technique of INL is reported showing the validity of the presented procedure.

Centrifugal pumps are widely used in industrial applications. Today pumps absorb nearly a quarter of the electric energy of the European industry. The purpose of this paper is to present a centrifugal pump model-based control system that ensures the energy benefits related to variable speed drive technique and provides the complete protection monitoring and machine diagnostic using a minimum number of installed sensors.

This paper deals with a data-acquisition system that has been specifically developed for a long-term monitoring of ten different photovoltaic plants. The main goals of the system consist in estimating the drift of the plant components, mainly photovoltaic modules and power inverters, and comparing the performance of the ten plants, which are based on different technologies and architectures. Owing to these goals, the traceabilityassurance of the obtained measurements is mandatory, hence the data-acquisition system has been designed to be easily calibrated and, if necessary, adjusted to compensate for measuring-chain drifts. In addition, the measurement uncertainty, which has to be suitable to distinguish the behaviour of the different PV plants, has to be stated for each of the estimated parameters. A brief description of the data-acquisition system is provided and its measurement capabilities are highlighted in terms of measured quantities and expected uncertainty. Results that refer to a period of thirty months are also reported.

In this work, a dielectric permittivity measurement system, to be used for quality control of edible oils, is presented. The proposed system relies both on low-frequency and high-frequency measurements (performed through and LCR meter and through a time-domain reflectometer, respectively), thus allowing a “broadband” investigation of the dielectric behavior of edible oils. The adoption of a single, specifically-designed probe (used for all the measurements), along with the possibility of using portable instrumentation, makes the proposed system an appealing candidate for the realization of a continuous, on-site system for quality monitoring of edible oils. The proposed system was first validated on materials with well-known dielectric characteristics. Successively, it was used to investigate the dielectric behavior of some autochthonous varieties of olive oils and of seed oils. The ultimate goal of this work is to pave the way for the development of an alternative method of analysis that could be able to distinguish among different kinds of oils, to certify oil quality and origin, and to detect the possible presence of adulterants.

This paper describes a theoretical approach to evaluate the uncertainty on the series and shunt resistances estimated by the seven-parameter (double diode) model of a photovoltaic (PV) cell using data commonly provided by panel manufacturers, measured environmental parameters, and semiempirical equations. After a brief survey on the state of the art and the treatment of the double-diode model, the procedure proposed by the authors, to estimate the unknown parameters, is illustrated. The theoretical expression of the uncertainty, which affects the estimation of the series and shunt resistances (namely, Rs and Rsh) of a PV cell, is then derived. A statistical analysis performed bymeans of a Monte Carlo simulation is in agreement with the theoretical expression of the uncertainty.

In this paper a hybrid solar system made with photovoltaic cells and thermoelectric modules has been analyzed. The theoretical energy conversion and the performance parameters have been investigated and compared with respect to design and geographic location using a simulated model. In particular, the effects of the global radiance, of the ambient temperature and of the hours of sunshine on the power and energy production are assessed. The obtained results show that the advantages of the thermoelectric modules use are less significant when the locations considered are very distant from the equator.

The paper presents ideas and observations about the use of the frequentist and the Bayesian approach to estimation and uncertainty. The merits and the pitfalls of the Bayesian approach, compared with the frequentist one, are illustrated using a simple example, which gives rise to an instructive paradox. The impact of the paradox on the GUM approach to uncertainty prescribed in Supplement 1 is highlighted and discussed.

BiomedicalKeywords—Biomedical x-ray imaging, image quality, phantom, image contrast, radioation dose.

Il costante sviluppo del turismo e delle attività industriali, pone una pressione sempre crescente sull’ambiente, alterandone gli equilibri e costituendo un rischio per la salute umana. Tra le principali cause di natura antropica vi sono le acque di scarico e i fertilizzanti agricoli che, riversandosi in mare, apportano sostanze in grado di promuovere o limitare la proliferazione di micro alghe (fitoplancton), organismi alla base dell’ecosistema marino e della catena alimentare. Tuttavia, nella pratica comune, la concentrazione di micro alghe in mare non viene misurata direttamente ma è piuttosto la concentrazione di clorofilla-a in esse contenuta (in mg/m3) ad essere riconosciuta nell’ordinamento vigente come unico parametro biologico per la determinazione della classe di benessere di appartenenza di un corpo idrico.