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Pasquale Arpaia, Carlo Manna
DEVELOPMENT OF A WEB-SERVICE E-DIAGNOSTIC AND E-MAINTENANCE FRAMEWORK FOR INDUSTRIAL MONITORING

An integration in a framework of e-diagnostic and e-maintenance components based on web-services has been developed for industrial monitoring systems. The aim is to perform tele-monitoring, diagnostic and maintenance tasks for industrial monitoring systems working in dynamic conditions of commitments, suppliers, and customers. The framework has been customized initially for an elevator machine system for improving service performance in companies of installation and maintenance. The experimental case study, reported in the present paper, shows encouraging results and fosters industrial technology transfer.

Daniele Gallo, Carmine Landi, Mario Luiso, Nello Polese
ELECTRIC POWER GRID AND MEASUREMENT TASKS IN THE EUROPEAN UNION

Over the last years, the structures of electrical power supply changed noticeable. Centralistic conventional power generation is supplemented by distributed energy resources. Trends of energy demands let know that amount of solar and wind energy will progressively increase, very often with a relevant amount of distortion: this gives emphasis to power quality evaluation. Proper metering in non-sinusoidal conditions and, thus, large bandwidth transducers are required. Two different approaches to solve the problem of classical instrument transformers are proposed: one is substituting them with new low cost insulated electronic transducers, another is improving performances of the already installed IT, through the use of digital compensation devices. It has been proven that both the solutions solve the problems of high accuracy and large bandwidth, necessary for accurate measurements in new energy scenario.

G. Andria, F. Attivissimo, N. Giaquinto, A.M.L. Lanzolla
A NEW TECHNIQUE TO IMPROVE THE QUALITY OF MEDICAL IMAGES

The purpose of this study is to assess the effect of different noise reduction filters on medical images. In particular Computed Tomography (CT) and Magnetic Resonance (MR) images are analyzed because they represent the most used diagnostic techniques in radiologist field. In a first step the statistical properties of noise that affects CT and MR images are investigated. Then a denoising technique was applied on CT and MRI applications to show the differences in the performance of the proposed method and to highlight in both cases the limits and the advantages.

Peter Višnyi, Jaroslav Dudrík, František Ďurovský
DIGITALLY CONTROLLED CURRENT SOURCE FOR TESTING CIRCUIT BREAKERS

This document deals with a digitally controlled current source used for testing magnetic overcurrent releases of circuit breakers. The magnetic overcurrent releases of circuit breakers operate at much higher current than the nominal current. They are tested by a special current sources capable to provide currents up to hundreds or thousands of Amperes with an accuracy of a few percents. These current sources are designed for operation at very low voltage, typically less than 10 Volts (RMS) and at very short testing time (typicaly 100 ms) with long idle period. This document describes the digital current control that is very specific from the viewpoint of technical requirements as well as the used control method – digital current control without direct feedback.

Daniele Gallo, Giacomo Ianniello, Carmine Landi, Mario Luiso
AN ADVANCED ENERGY/POWER METER BASED ON ARM MICROCONTROLLER FOR SMART GRID APPLICATIONS

The Smart Grids are an electricity delivery system which monitors, protects and optimizes the operation of its interconnected elements from end to end. They include central and distributed renewable energy generators through the electrical network. Thus, it can easily be argued that they are characterized by great issues to manage the whole system and to assuring a proper energy quality. In this scenario the possibility to have advanced power/energy meter with energy quality monitoring and communication capabilities is of great interest. So, in this paper the design and implementation of a wattmeter for single phase electrical systems based on an ARM microcontroller is presented. The wattmeter is composed of measurement transducers (for voltage and current), conditioning, acquisition, processing and communication sections; the last three are embedded in the microcontroller. Other than typical wattmeter tasks, the system is capable to measure some power quality parameters. Moreover communication is performed through an USB based transfer block to an Host Pc, through which it can be configured. Even if it is designed to respect on-line measurement constraint, it remains a low cost system. In the paper experimental results related to characterization are also described.

D. Giordano, M. Borsero, G. Crotti, M. Zucca
ANALYSIS OF MAGNETIC AND ELECTROMAGNETIC FIELD EMISSIONS PRODUCED BY A MRI DEVICE

The results of a magnetic and electromagnetic measurement survey are presented, which was carried out around a Magnetic Resonance Imaging device. The investigation is performed with the twofold aim of characterising the field source under the different operating sequences and evaluating the exposure of workers both to the static and time-varying magnetic field. The exposure levels are estimated, as a function of the position of the workers and the field characteristics, and their compliance with the existing and possible new limits is discussed. Critical situations are put in evidence in relation to both the exposure limits and the performance of the available measuring instruments.

Cristian Zet, Cristian Foşalău
IMPROVED DIGITAL PHASE MEASUREMENT

The paper presents a new method for measuring the phase shift between two signals. The method can be used as full FPGA implementation or in microcontroller based systems. In contrast with the classic method, where the measuring time is obtained from the reference clock signal by dividing it with high value factors, this method gets the measuring time from one of the signals by dividing it with a small factor, 10 for example. Thus, it results a dramatically diminish of the measuring time or a significant error improvement.

Michal Kubínyi, Radislav Šmíd
COMPARISON OF TIME-FREQUENCY DISTRIBUTIONS FOR PULSE-ECHO ULTRASONIC EVALUATION AND FILTERING

For a direct evaluation of ultrasonic signals it is necessary to analyse data with an acceptable level of noise. Ultrasonic signals represent a specific category of time domain signals to be analysed. In order to increase difference between the level of noise and the amplitude of the ultrasonic pulse a proper method for data differentiation has to be used. Within this article are discussed and compared two time-frequency distributions. The first approach is via wavelet transform. The second proposed method is S-transform. This transformation has been recently introduced for ultrasonic echo analyses. This tool represents intermediate stage between the Fourier transform analysis and the Wavelet transform analysis. In order to filter ultrasonic signals from Electromagnetic Acoustic transducer with a high level of noise, new, different approach was developed. The result showed complexity of the ultrasonic signal and noise in case of the Electromagnetic Acoustic Transducer. We designed the new adaptive signal processing method, which performs well on studied ultrasonic signals.

M. Catelani, L. Ciani, A. Zanobini
SOME REMARKS ON A BIVARIATE ANALYSIS IN THE PROPAGATION OF MEASUREMENT UNCERTAINTY AS AN ALTERNATIVE APPROACH TO THE MONTE CARLO METHOD

Recent literature shown that in cases where there is strong interdependence between direct measures involved in an indirect measurement, or when the uncertainties of direct measures are not as small as one would wish, or again, when a strong nonlinearity ties the measures involved to each other, the Monte Carlo method, proposed by Supplement 1 to the “Guide to the expression of uncertainty in measurement” (GUM), manages in most cases to obtain a more accurate measurement uncertainty evaluation than the one actually proposed by the GUM and bound to Taylor series developed.
This paper aims to offer a new approach related to bivariate analysis of standard models such as sum and product of measures when it is either possible, or unsuitable, to apply the two methods quoted in Supplement 1.

Pasquale Arpaia, Lucio Fiscarelli, Carlo Petrone, Nicola Cardines
DESIGN OF AN ON-LINE DYNAMIC MAGNETIC FLUX ANALYZER BASED ON DOUBLE-BUFFER SLIDING DFT

An on-line dynamic magnetic flux analyzer for magnetic measurement is presented. The instrument achieves on-line harmonic analysis by means of an improved implementation of the sliding DFT algorithm on the basis of the Fast Digital Integrator. In particular, the round-off error, unacceptable in digital integrators, is corrected by employing two buffers alternatively. Details about the structure of the instrument and the algorithm implementation are pointed out, and some experimental results are analyzed in order to validate the proposal.

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