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Susumu Sakano, Satoru Shoji
Generation of Robot Motion Based on Measurement of Human Movement

The robot plays active part in the product field and the humanoid robot is intended to enter into our human life in near future. When the humanoid robot may enter into our daily life, the various problems are occurred and must be solved. One of the most important problems is how to moves like human and how to work like human. In this research, the human walking motions are measured using motion capture system and the simulation of the robot walking motion is carried out using the results of the motion capture measurements. It was confirmed that the humanoid biped robot can walk like the human walking from the experimental results.

P.Camino, D.Dallet, B. Quertier, A.Baudry, B. Le Gal, G.Comoretto
A Multi-rate Filter for Broadband Radiotelescopes

We have investigated the implementation of various structures based on the Cascaded Integrator Comb (CIC) filter to replace the decimation filter in the first stage, 32-time demultiplexed input digital filter of the large Correlator System of the ALMA (Atacama Large Millimeter Array) interferometer project. The main goal of this study is to reduce the power dissipation in the 2-stage, 32-time demultiplexed ALMA digital filter implemeneted in large FPGA's by optimizing the used number of logic elements available in these chips. Different modified CIC filter implementations are presented and compared in terms of complexity and power performances. We conclude that a CIC filter with a Quarter-band filter significantly improve the overall power dissipation and thus the ALMA filter efficiency.

Traian Chiulan, Brândusa Pantelimon
The Importance of the Short-Circuit Impedance Measurement To the Operation of the Transformer Units

Knowledge of the short-circuit impedance variation is necessary for verifying the observance of the technical conditions (including the design conditions), certain nonconformities in the winding execution, checking the winding behavior in operation, verifying the system and short-circuit calculation (including the correct protection setup), the loading of the same type units, or more importantly, of the different type ones. The measurement of the short-circuit impedance by means of a three phase low voltage power source can be performed because the value of impedances does not depend on the applied voltage. ICEMENERG has developed a modern measurement system that has been used for performing a great amount of measurements, the results of which have been compared with those of the manufacturer’s, and with those obtained by means of high voltage measurements.

Pier Paolo Capra, Flavio Galliana, Milena Astrua, E. Gasparotto
Use of a 100 MΩ step Hamon resistor for calibration of pico-ammeters in dc current in the range 100 pA ÷ 100 nA

This paper describes a measurement circuit for the calibration of pico-ammeters in dc current. The system is based on a 100 MΩ Hamon network developed at INRIM to improve the traceability level of the maintained 1 GΩ standard. Besides the Hamon network, the measurement system, presented in this paper, consists of a precision dc voltage source and an electronic circuit used as voltage guard driver.

Liviu Florin Zoran, Carmen Ionescu Golovanov
Satellite Data Fusion For Analysis Of Coastal Zone Changes

This study focuses on the assessment of coastal zone land cover changes based on the fusion of satellite remote sensing data.The evaluation of coastal zone landscapes is based upon different sub- functions which refer to landscape features such as water, soil, land-use, buildings, groundwater, biotope types. Mixed pixels result when the sensor’s instantaneous field-of-view includes more than one land cover class on the ground. Based on different satellite data (Landsat MSS, TM, ETM, ERS, IKONOS, ASTER and MODIS) was performed object recognition for North-Western Black Sea coastal zone. Preliminary results show significant coastline position changes of North Western Black Sea during the period of 1975-2005.

Slobodan Ðukanovic, Mauro D’Arco, Leopoldo Angrisani
Instantaneous Frequency Estimation Of Multicomponent Signals Characterized By Interfering Linear Trajectories

The paper deals with signals that include nonstationary components. For these signals, the estimation of the instantaneous frequency of each component is especially difficult in time intervals where its trajectory interferes with another one, for example by crossing it. The attention is mainly paid to linear trajectories, seeing that any trajectory can be generally approximated as linear in the nearby of the crossing point. The authors propose a method based on the use of a two dimensional subspace of the chirplet transform, known as bowtie subspace, that allows accurate estimates of the instantaneous frequency even in the presence of crossing trajectories. The use of a restricted subspace allows a reduced computational burden and less time consumption with respect to several approaches based on advanced multiparametric transforms, typically exploited when multicomponent nonstationary signals are analyzed. The performance granted by the proposed method is assessed through a number of tests performed on simulated, emulated, and real signals.

Valeriy Martynyuk, Denis Makaryshkin, Juliy Boyko
Electrochemical Supercapacitor Time Domain Analysis By Means Of Multi-Channel Measurement System

In this paper we present the multi-channel measurement system based on potentiostatic, galvanostatic and potentiodynamic methods or combinations of the given measurement methods. The multi-channel measurement system is controlled with the special developed software. This system enables to perform the electrochemical supercapacitor time domain analysis more completely and with high accuracy.

Valeriy Martynyuk, Denis Makaryshkin, Juliy Boyko
Frequency Domain Analysis For Electrochemical Supercapacitors

The paper deals with the problem of creating a non-linear model of the electrochemical supercapacitors and measuring their electrical parameters in wide frequency range. Formalization of the model as a non-linear equivalent circuit enables to explain non-linear behavior of electrochemical supercapacitors such as dependence of their capacity and electrical series resistance (ESR) on the different voltage levels and frequencies. In order to determine the non-linear supercapacitor equivalent circuit parameters we carry out the impedance measurements and then perform fitting of obtained measurement results by means of impedance function, which describes the electrochemical supercapacitor non-linear properties with greater accuracy.

Gordan Štruklec, Vedran Bilas
Wireless Automatic Water-meter Reading System

Wireless automatic meter reading (AMR) system based on a fixed radio network brings many advantages when compared to other meter reading techniques. After an introduction to the state of the art of AMR systems in general, and particularly of water meter reading system, a wireless automatic water-meter reading system founded on ZigBee technology is presented. Set forth in the text are main characteristics of this low cost and low power system. The benefits of imlementing ZigBee protocol as the solution for the imposed requirements are rather thoroughly discussed, mainly in the aspect of network configuration as the basis for robust data transmission, wide area signal coverage and lowering devices’ power consumption.

Boris Šnajder, Darko Vasic, Vedran Bilas
A Digital Signal Processing Technique for Pulsed Electromagnetic Inspection of Steel Tubes

A pulsed electromagnetic (PEM) technique is an effective method of nondestructive evaluation of steel tube inner diameter and wall thickness. Using time-spatial separation of direct-zone and remote-zone signals, it is possible to determine wall thickness and inner diameter with one receiving coil measuring voltage peak and zero-crossing time simultaneously. However, for fixed coil geometry the zero-crossing time can be recognized only for a limited range of wall thickness. In order to increase wall thickness range and shorten the probe, additional processing of the pulsed-eddy current signal must be applied. In this paper, we present a technique based on integration of the pick-up voltage and measurement of threshold-crossing time. The technique can be easily implemented in the existing PEM tool. We have verified the technique using numerically and experimentally obtained results for a range of tubes specified with API 5CT standard.

Page 810 of 936 Results 8091 - 8100 of 9356