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Antonio Cataliotti, G. Tinè
ON THE MODEL OF MV POWER LINE COMMUNICATION SYSTEM IN THE CASE OF LINE TO LINE TRANSMISSION

In this paper a complete model of Medium Voltage (MV) power system for PLC communications, in the frequency domain, is presented. A simple and friendly Simulink® software is used to develop the model. A distributed parameters MV cables model in line-line configuration is considered. Also the signal coupling networks with the generation and receiving systems are included. The performances of the complete PLC communication system are evaluated introducing the attenuation constant computed as ratio between the received and transmitted voltage signals. The signal losses produced by the complete system in the CENELEC frequency band and for different cable lengths are also considered.

Artur Skórkowski, Adam W. Cichy
VIRTUAL CAPACITANCE METER BASED ON IMPEDANCE MODULUS MEASUREMENT

The capacitance can be calculated from the impedance modukus value of the object under test. It is possible, if a two-terminal network is represented by a series connection of a resistor and a capacitor and the reactance of the capacitor is considerably greater than the resistance (e.g. in a low-loss capacitor) In this case the error of the approximation can be omitted. A virtual realization of such meter has been presented in the paper. This one shows the idea of the signal processing in the quasi-balanced circuit. Quasi-balanced circuits are the AC circuits designated for impedance component measurements. Similar as teh balanced circuits, the quasi-balanced circuits have a special status called a quasi-balanced status. This is usually a phase shift between two selected signals of the circuits. The circuit is driven to the quasi-balance status by controlling of only one variable element and then the value of the measured impedance component can be calculated using the adjusted value of the variable element. The meter has been built with the application of the data acquisition card USB NI-6009, which has been controlled by a software programmed in the LabVIEW environment.

Andrzej Met, Krzysztof Musiol, Tadeusz Skubis
MULTI-RANGE TRANSFORMER BRIDGE FOR CALIBRATION OF INDUCTANCE STANDARDS

A high-precision multi-range unbalanced transformer bridge designed for inductance standard calibration is described. Basic theory of the bridge is discussed which enables direct measurement of differences of both impedance components (ΔL and ΔR). The instrument was designed to compare inductors from 100 mH to10 H in the frequency range from 100 Hz to10 kHz. The uncertainty of comparison in the impedance range from 1 W to 10 kW is assessed to be smaller than 10 ppm.

Domenico Luca Carnì, Domenico Grimaldi, Francesco Lamonaca
IMPROVED SYNCHRONIZING PROCEDURE OF PDAS TO DELIVERY THE COMMON SENSE OF THE TIME TO STAND ALONE MEASUREMENT INSTRUMENT

The paper proposes the optimized evolution of the previous procedure to synchronize the PDAs to the node of the Distributed Measurement System (DMS) in order to physically bring the common sense of time to the stand alone node. The improvements concern with
(i) the selection of the clock node as reference one,
(ii) the contemporaneous synchronization of all the involved PDAs, and
(iii) the compensation of the effects of the drift of the electronic components on the number of system cycle after whom the control of the MI must be executed. The improvements pointed out originate from the practical evaluation of the performance of the previous synchronization procedure. The improved procedure meets the advantages of the synchronization based on the IEEE std 1588. Experimental tests are shown to validate the synchronization procedure and to highlight the advantages.

M. N. Durakbasa, P. H. Osanna, M. E. Yurci, P. Aksoy
CONTACT AND CONTACTLESS INVESTIGATIONS OF MANUFACTURED HIGH-PRECISE SURFACE STRUCTURES

Surface roughness is the measure of the fine irregularities of a surface. Correct function of the manufactured component is critically dependent on its degree of roughness. There are different techniques applicable for surface metrology analysis. This paper presents the analyses of manufactured high-precise surface structures using the results of contact and contactless measurement techniques. The surface structure is primarily a function of the used production processes.
During this experimental work, all measured surface roughness parameters have been analyzed by using SPSS 15 statistically. "Linear Regression" of Ra parameter estimated the coefficients of the linear equation, involving a few independent variables (feed in mm, periodicity, type of material, contrasting, type of production process etc.), that best predicted the value of the dependent variable and the mathematical model giving the values of roughness parameter has been established in terms of feed in mm, the periodicity, contrasting and type of material as a result of the statistical analyses in this experimental study.

Pingyu Zhu, Hongyang Zeng, Guilin Jiang, Yang Zhou
A NOVEL SENSOR FOR MONITORING SETTLEMENT

In this study we describe a new concept for a sensor using fully distributed sensing along optical fibres designed especially for monitoring lateral movements in embankments and settlement areas, and deformations of excavation walls and tunnels. The sensor design includes four components: mass block housing, middle cylinder, connector housing, optical fibers and mass-block. The block housing is to hold the mass block and guide its sliding. Two blocks are designed to stretch sensing optical fiber when the block housing has inclination. The sensing optical fiber are required for performing sensing task in a ela range. One end of the whole pipe sensor is fixed to a pole, which was deeply embeded in soil of embankment dam. The permofmance of designed pipe sensor was carried out by a loading model of the dam settlement. DiTeSt-STA202 is then adopted to read and determine the sensitivity of the pipe sensor, which is the most impotant parameter for a sensor. The sensor provides a useful and precise method to detect and mornitor inside change of the embankment dam, as well as to detect and mornitor the settlement of other structures.

Mirko Marracci, Bernardo Tellini, Carmine Zappacosta
FEM ANALYSIS OF ROGOWSKI COILS COUPLED WITH BAR CONDUCTORS

We study the behavior of Rogowski coils coupled with bar conductors under quasi-static conditions. Through a finite element (FEM) analysis, we estimate the current distribution across the bar and the flux linked by the transducer for various positions of the primary conductor and for various operating frequencies. Simulation and experimental results are reported in the text.

Edwardo Arata Y. Murakami
REACTION TIME MEASUREMENT APPLIED TO MULTIMODAL HUMAN CONTROL MODELING

The final goal of this research is to analyze the human visual and force sensory feedback integration related to a manipulation task and build a control model of a human operator. In this primary work the reaction time was measured to determine the time lag constant of each subject. During the measurement of the reaction time, fluctuations in the pupil size and heart beat were verified and the both had first order lag characteristics but there were no correlation with each other. In order to improve the human control model the identification and implementation of this kind of fluctuation will be discussed.

Andrzej Odon
ANALYSIS OF A FEEDBACK DRIVER FOR SEMICONDUCTOR LIGHT SOURCES

The paper presents analysis of an electronic system of a driver with the feedback optical loop used for stabilization of radiation power of a semiconductor light sources such as CW laser diodes (LDs) or light-emitting diodes (LEDs). The analysis has permitted derivation of the strict form of static equation describing the relation between the optical output power and the electrical driving signal. The considerations are based on general feedback analysis procedures. A detail metrological analysis of the influence of instabilities in the parameters of the driver system on the value of the optical power of light source is presented.

José Santo Guiscafré Panaro
A NEW APPROACH TO DEMAND MEASUREMENT OVER THE ELECTRICITY DISTRIBUTION NETWORK

This work proposes a method that allows the remote measurement of the electric power demand of clusters consisting of a small group of consumers that are connected to a line section of the distribution network and concentrated in an electricity pole.
The method is based on the detection of the electrical current and voltage changes at both ends of a distribution line section, and then computing the demand of the clusters. Due to the statistical nature of the electricity consumption, coincident demand steps of the users can cause some error that can be considered as noise perturbing the measurement signal. The measurement error characteristics are predicted through simulation.
The obtained results show that the new technique can be an efficient tool to reduce technical and non-technical losses in the electricity distribution network.

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