Andrew Henry, Francis Labrique, Christian Eugène
Swinging bells deliver the best sound quality when the swinging angle is kept to a specific value proper to each system. The aim of our paper is to propose an original method for controlling this swinging angle without any external sensor, by using the driving motor (actually a threephase induction machine) as a sensor when it is not active as a motor. In the sensor mode, we control the maximum speed of the bell, which is related to the swinging angle by a timeinvariant mechanical coefficient specific to each bell system. The main advantage of the proposed solution is that the speed...
XVII IMEKO World Congress
· TC4
· 2003
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W. Winiecki, A. Kuran, R. £ukaszewski
Remote, wireless controlling of distributed virtual instrument (DVI) using GSM mobile phones is considered. Interactive WAP service is applied to configure measuring system, to control measurement process and to access to measurement data. The service is based on ASP technology and dynamic databases. National Instruments PC-1200 DAQ card, programmed with LabVIEW, was applied to design a wireless DVI (WDVI).
XVII IMEKO World Congress
· TC4
· 2003
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Pekko Vehviläinen, Kimmo Hätönen, Pekka Kumpulainen
Quality analysis of a digital mobile telecommunications network can be a daunting task. For monitoring and operating purposes hundreds of measurements are constantly collected from a complex network. From the measurements the operating personnel of the network should be able to detect the hanges that affect the service quality that the subscriber expects. Data mining methods can be used to ease the operating staff’s task.
XVII IMEKO World Congress
· TC4
· 2003
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Balázs Vargha, László Sujbert
Quality of power sources is mainly increased by using better components and tricky electronic circuits. The paper introduces a control loop, which is similar to that used for the active cancellation of acoustic noise signals. In the feedback loop, the distortions of the signal are estimated by a combination of an adaptive Fourier analyzer and a resonator-based observer. Only the distortions should be compensated, therefore the actuator signal has low power. The paper introduces the active distortion reduction system and presents practical results, as well.
XVII IMEKO World Congress
· TC4
· 2003
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Arkadiusz Szewczyk, Ludwik Spiralski, Gérard Ghibaudo, Gilles Reimbold, J. A. Chroboczek
A novel system for low frequency noise, LFN, wafer-level (point probe) measurements and a method of the system calibration with the thermal noise of resistances are discussed. We also present some LFN data on MOSFETs as an example of implementing the LFN measurement technique for the device quality diagnostics.
XVII IMEKO World Congress
· TC4
· 2003
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Andreas Stelzer, Robert Hauser, Leonhard Reindl, Rüdiger Teichmann
A solution for uniquely identifying any sensor connected to an evaluation unit without direct electrical connection to the existing measurement line is presented. The proposed solution is compatible with existing measurement systems, operates completely passive, and withstands temperatures up to 400°C as well as shocks up to 3500 g. The identification tag itself, which carries a unique serial number, is realized by a high-temperature stable surface acoustic wave (SAW) device. A low-cost radio frequency (RF) interrogation unit, which shares the existing sensor cable, is used for reading the...
XVII IMEKO World Congress
· TC4
· 2003
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Sergiej Taranow, Andrzej Olencki, Yuri Tesik
Pulse amplifiers are widely used in radio engineering. The first requirement to these amplifiers is to provide minimal distortion of rectangular pulse shape. The second is provision minimal multiplication error, which is important for measurements. The standard method, grounded on the usage of negative feedback, may be used for wide band periodical signals and unacceptable for amplification pulse signals due to a signal delete in the forward and backward branches. It is proposed to use for this problem solution, borrowed from cybernetic engineering, the adaptive method with small test signal...
XVII IMEKO World Congress
· TC4
· 2003
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Janusz Smulko
The new method of electrochemical noise (current and voltage fluctuations) measurements is presented. The proposed method can characterise local corrosion events while the other electrochemical methods are much less effective than electrochemical noise measurements. The new measurement setup is proposed. The system can identify metal surface where local corrosion events take place. The realized measurement system is described in detail. All the practical problems of noise measurements and methods of outside distortion reduction are presented. The preliminary measurement results are also...
XVII IMEKO World Congress
· TC4
· 2003
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Janusz Smulko, Kazimierz Darowicki, Artur Zieliñski
The results of electrochemical noise measurements and their analysis for evaluation of corrosion intensity in the water supply system are presented. The polarization resistance Rp is calculated for corrosion evaluation, estimated by applying the proposed method of noise analysis. The method includes trend removal and impedance calculation by dividing power spectral densities of the detrended voltage and current fluctuations. The estimated impedance at low frequencies is used for Rp value calculation. The applied algorithm of electrochemical noise detrending is based on its decomposition and...
XVII IMEKO World Congress
· TC4
· 2003
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Ferran Reverter, Josep Jordana, Ramon Pallàs-Areny
Measurements based on triggering a time counter display trigger uncertainty, which depends on input signal noise and slew rate, and on input channel noise. This last is specified for bench-top instruments but not for microcontrollers with embedded time counters, which are very attractive to implement period-to-code converters intended for sensor interfaces. Because power-supply rails in digital systems are very noisy, we have analysed the effect of Gaussian white noise and sine wave interference added to the PIC16F873 power supply pin. For a triangular input signal, the standard deviation of...
XVII IMEKO World Congress
· TC4
· 2003
· Download