Flavio Galliana, Pier Paolo Capra, Iulian Mihai
At the National Institute of Metrological Research (INRIM) a comparison between the measurements of a commercial high resistance bridge and two validated high resistance methods from 100 GΩ to 1 PΩ has been performed. The systems showed satisfactory agreement except at 1 PΩ. The commercial bridge recently has been improved by means of a new software revised by the manufacturer according to the INRIM requests. This software allows the automatic calibration of the DC Voltage sources of the bridge, with a high precision DMM, taking into account these calibration results in the subsequent...
Oleh Velychko, Irina Karpenko, Stanislav Karpenko, Tetyana Gordiyenko
Particular interest is the question of the development and practical application of alternative methods for processing data of international comparisons. The paper is considered the alternative method for processing of international comparison results, which based on preference aggregation method. Processing of COOMET.EM-K5 key comparison data for power by the preferences aggregation method is presented. The results are compared with the traditional approach and the considered alternative method.
Damir Ilić, Ralf Behr, Jinni Lee
The experimental application of the AC Quantum Voltmeter, developed at PTB, for the calibration of a source (i.e. calibrator) or a meter (i.e. ammeter) at a low-frequency AC current is described in this paper. The current measurements (from 2 mA to 2 A) are based on the voltage drop generated on an AC-DC shunt and measured by the AC Quantum Voltmeter. To obtain uncertainties at A/A level (i.e. ppm - parts per million), a self-heating of the shunt and careful settings of the measurement procedure should be considered. In this experiment, a Fluke 5720A1 calibrator is used as the current...
Zexin Guan, Mei Yang, Wenqiang Li, Xuefeng Ma, XinyanWang, Shang Wang
The bullet speed measuring device is an instrument for measuring the speed of bullets, which is widely used in public security systems, judicial identification departments, gun performance research institutions, etc. For bullet speed measuring devices, speed is the most important parameter. This article provides a method for measuring the speed of a bullet speed measuring device and an analysis of the uncertainty in measurement . There are two methods to calibrate the speed: simulation method and live ammunition method. The simulation method selects a signal generator with a time base...
Platon Sovilj, Bojan Vujicic, Dragan Pejic, Aleksandar Radonjic, Vladimir Vujicic
The paper proposes a method and device for on-line temperature measurement with Pt-100 sensor operating in a nonlinear mode. The sensor measures the temperature in range of 0 °C to 200 °C, whereas the measured data are processed by applying a two-bit stochastic digital measurement method. The proposal is theoretically analyzed and tested experimentally. It is shown that the accuracy of the method depends on the accuracy of the sensor. At a sampling frequency of 1 MHz, the maximum accuracy is reached in 17.5 s and is equal to 0.015 % of full scale (FS). On the other hand, when the measurement...
U. Cesaro, H.Coppier, P.Arpaia, M.Chadli, D.Gatti, M.Pezzetti
In this work, an accurate, low-cost electronic angle-meter is designed, manufactured and metrologically characterized. The idea at the basis of the proposed electronic goniometer is to transduce the mechanical rotation into the variation of an electrical quantity, namely a resistance. Then, such a variation can be easily measured through a low-cost multimeter used as an ohmmeter. The metrological characterization of the prototype demonstrated that the proposed system can achieve an uncertainty as low as 1° with costs of an order of magnitude lower than devices currently available on the...
Jakub Svatos, Jan Belak, Jan Holub
At present, acoustic detection techniques of gunshots (gunshot detection) are increasingly being used not only for military applications but also for civilian purposes. Detection, localization, and classification of gunshots employing acoustic detection is perspective alternative to visual detection, which is commonly used. In certain situations, to detect a source of a gunshot, an automatic acoustic detection system may be preferable. This paper presents a system for acoustic detection, which can detect localize and classify acoustic events such as gunshots. Tested firearms are 9 mm short...
Andrea Zancla, Serena De Santis, Andrea Scorza, Salvatore Andrea Sciuto, Giovanni Sotgiu, Monica Orsini
Fourier transformed infrared (FT-IR) micro spectroscopy has become a reliable, non-destructive and automatic tool to analyze the chemical differences in biological samples associated with healthy or diseased states for diagnostic or biomedical research purpose. To extract useful information from the huge number of spectra usually recorded, statistical multivariate analysis is applied and careful data pretreatment to reduce or eliminate possible sources of error is necessary. In this regard, a quantitative criterion to evaluate the performance of different methods applied in the most...
Giorgia Fiori, Fabio Fuiano, Federica Vurchio, Andrea Scorza, Jan Galo, Silvia Conforto, Salvatore A. Sciuto
PW Doppler Ultrasound (US) is commonly used in clinical practice for cardiovascular applications. Nowadays, the performances of a Doppler system are difficult to assess because a shared worldwide standard is lacking. This work aims at giving a contribution in the field, by defining a new index for PW Doppler Quality Control (QC) by using a commercial flow phantom, namely, the Lowest Detectable Signal in the spectrogram image, which scientific literature referred to as an index of PW Doppler sensitivity. A novel automatic algorithm for the estimation of such an index has been developed and...
Giorgia Fiori, Fabio Fuiano, Federica Vurchio, Andrea Scorza, Maurizio Schmid, Silvia Conforto, Salvatore A. Sciuto
The maximum Ultrasound (US) Depth of Penetration (DoP) is one of the most important parameters related to medical US systems sensitivity. DoP is also suitable for characterizing those systems since it is usually measured in routine quality controls (QC) of ultrasound scanners. In common practice, DoP assessment is carried on visually and may be affected by various external factors, such as the operator related errors. To minimize these errors, image analysis algorithms have been proposed even if without a complete performance assessment. In the present work, a novel method for the automatic...