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Leopoldo Angrisani, Antonio Langella, Michele Vadursi
NEW DIGITAL SIGNAL-PROCESSING APPROACHES FOR MEASURING POWER CCDF CURVES

Signals peculiar to modern telecommunication systems are characterized by higher peak-to-average power ratios than in the past and can potentially lead to higher distortion in amplification stages if signal power statistics are not accounted for properly. CCDF (Complementary Cumulative Distribution Function) curves are an effective way of fully specifying signal power characteristics. Some high performance analysers, currently available on the market, carry out CCDF measurements through a demodulation of the radiofrequency signal and the application of custom digital signal-processing algorithms to the samples of the baseband components thus retrieved. Two alternative digital signal-processing approaches for measuring CCDF curves are presented in the paper. The major advantage they offer consists in the absence of demodulation; they are, in fact, based on original algorithms that are directly applied to the samples of the radiofrequency signal.

Alexandru Salceanu, Mihai Cretu, Valeriu David, Eduard Lunca
DETERMINING ESD THREATS FOR A HUMAN-FURNITURE MODEL IN MOTOR VEHICLES

The paper presents some performed measurements and investigations in the framework of the triboelectricity developed in a motor vehicle. The concern about ESD induced failures is growing up in the same manner as the electronic content of an up-to-date car. Assuming the furniture ESD model, were measured or evaluated its parameters for the situation “person inside the vehicle” and “person getting out from the vehicle”. With an electrostatic head were measured the different values for ESD charging inside the vehicle. This study offers useful information in order to develop an ESD simulator and to reduce the fails and errors due to ESD phenomena in a modern car.

Dušan Agrež
POWER MEASUREMENT IN THE NON-COHERENT SAMPLING

An algorithm to improve the estimation of the active power of electrical systems in the non-coherent sampling is proposed in this paper. It is based on smoothing sampled data by windowing, and then averaging of the DFT (discrete Fourier transform) coefficients in the frequency domain to reduce leakage effects. The simulation and experimental results are presented showing that averaging of DFT coefficients provides better estimation of the active power then only by windowing. The use of a suitable algorithm depends on positions of the frequency components, on a number of observed periods, and on signal to noise ratio.

Tomasz Tarasiuk, Mariusz Szweda
A FEW REMARKS ABOUT NOTCHING ANALYSIS - CASE STUDY

This paper has been focused on the problem of analysis of notching occurring in electric power systems. Especially a choice of appropriate sampling frequency and its consequence for results of the analysis have been considered. Moreover, the problem of wavelet filter length and, in some respect, wavelet family has been analyzed as well. All analyses have been based on the real voltage samples, registered in the real isolated electric power system, namely ship’s system, during two different electric power plant configurations. Finally, results of the research have been commented on with respect of its impact on a whole device for power quality analysis.

R. Micheletti, R. Pieri
INSTANTANEOUS AVERAGE ACTIVE POWER MEASUREMENT FOR BUILDING ENERGY MANAGEMENT SYSTEM

Fast and accurate measurement of the instantaneous average active power is useful for building Energy Management System (EMS) in order to assure quality of service such as continuity, optimize energy consumption and reduce carbon dioxide emission.
In this paper the problems connected to the measurement of the instantaneous average active power for energy usage improving are discussed, also as the operational processes which deal to solve such problems.

Peter Fuchs, Ján Hribik, Miloslav Hruškovic, Branislav Lojko, Rastislav Michálek
DIGITAL POWER AND ENERGY MEASUREMENT

A brief description of the designed digital sampling electricity meter based on the modern Texas Instruments TMS320C6711 DSP is given. The electricity meter measures basic electric network parameters such as rms values of voltages and currents, powers, energy, power factor and net frequency. A brief discussion of measurement accuracy and error correction is also given. The designed calibration procedure of the current and parasitic phase shift between the measured voltage and current based on the active power measurement is described.

Marija Cundeva, Ljupco Arsov
EXPERIMENTAL VERIFICATION OF THE CAD ANALYSIS AND DESIGN RESULTS OF COMBINED CURRENT-VOLTAGE INSTRUMENT TRANSFORMER

In the paper modern CAD (computer aided design) techniques will be used for the analysis and design of a 20 kV combined current-voltage instrument transformer (CCVIT). The magnetic phe-nomena in the complex non-linear electromagnetic CCVIT system will be studied by using the finite element method in the three-dimensional domain and the original program package FEM-3D. The magnetic field analysis will derive the exact CCVIT metrological characteristics. The FEM-3D results are basis for further optimal CCVIT design from metrological aspect by using the stochastic method-genetic algorithm introduced in the original program as an instrument transformer design tool. The objective function during the optimization process is a combination of the CCVIT metrological parameters. Higher accuracy class will be achieved with the CCVIT optimal solution. The CAD results of the finite element method magnetic field analysis and the genetic algorithm optimal design will be experimentally verified through testing of the realized CCVIT prototype in a laboratory.

L. Ferrigno, V. Paciello, A. Paolillo
A LOW-COST MEASUREMENT SYSTEM FOR THE 3-D EVALUATION OF CAROTID PLAQUES BASED ON ULTRASOUND IMAGES

The paper describes an improved low-cost add-on measurement system for the 3-D analysis of carotid arteries. The system locates in the 3-D space the contours of vessel walls extracted from a series of 2-D acquisitions, thanks to the measurement of the geometrical parameters of the ultrasonic probe positions and orientations. Features of the proposed system include the possibility to realize free-hand measurements, to work with the desired number of images and to process both normal B-mode and Power-angio images. In the paper, the realized prototype will be described and its operation will be detailed and characterized both for the software and the hardware prototype.

I.N. Flaounas, D.K. Iakovidis, D.E. Maroulis, S.A. Karkanis
INTELLIGENT ANALYSIS OF GENOMIC MEASUREMENTS

In this paper we propose a methodology for intelligent analysis of genomic measurements. It is based on a sequential scheme of Support Vector Machines and it can be used for class prediction of multiclass genomic samples. The proposed methodology was evaluated using two lung cancer datasets. The results are comparable and in many cases higher to the accuracy of relevant methodologies that have been proposed in the literature.

Yukie Omori, Renshi Sawada, Susumu Sakano
INTEGRATED BLOOD FLOWMETER USING MICROMACHINING TECHNOLOGY

The micro machining technology has been advanced on the basis of the semiconductor manufacturing technology. In this study, the research on the manufacturing the integrated micro optical sensor accumulated LD and PD on the semiconductor substrate is practiced. The fabrication method is the technology of photolithography and etching technology in the semiconductor manufacturing. The blood flow meter is taken up as a typical application of the micro optical sensor.

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