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As. Ing. C. Dughir
VISUAL C++ COMPLEX MATHEMATICAL SIGNAL GENERATOR

This paper present a complex mathematical signals generator that can generate a combination of mathematical signals at the output of a PC sound card. The user can describe complex mathematical functions to be generated. The signal generator proposed is very simple to use and don’t require complex and expensive hardware to run.

Petr Struhovský, Ondřej Šubrt, Jiří Hospodka, Pravoslav Martinek
ADVANCED MODELING AND DESIGN EVALUATION PROCEDURE APPLIED TO PIPELINED A/D CONVERTER

This paper deals with a prospective approach of modeling and design evaluation applied to pipelined A/D converter architecture. In contrast with conventional ADC modeling algorithms targeted to extract the maximum ADC nonlinearity error, the innovative approach presented allows to decompose magnitudes of individual error sources from a measured or simulated response of an ADC device. This qualitative decomposition can significantly contribute to the ADC calibration procedure performed in term of integral and differential non-linearity. This is backgrounded by the fact that the knowledge of ADC performance contributors provided by the proposed method helps to adjust the values of on-chip converter components so as to equalize (and possibly minimize) the total non-linearity error. The proposed procedure is demonstrated on a system design example of pipelined A/D converter. Simulation results of each stage of the design evaluation process are given, starting from the INL performance extraction proceeded in a powerful Virtual Testing Environment and finishing by an error source simulation and modeling of pipelined ADC structure, suitable for a generic process flow.

Luka Ferković, Damir Ilić, Ivan Leniček
LABORATORY CURRENT TRANSFORMER BASED ON ROGOWSKI COIL

This paper cover the analysis and construction of current to voltage transducer based on Rogowski coil which satisfy the requirements of high-accuracy measurement of AC current (up to 20 A at power supply frequency, with the aiming uncertainty of 100 parts per million). Primary source of ac current uncertainty measured by this type of transducer is nonuniform density of turns which, in case of eccentricity or shift of primary conductor results in deviations of mutual inductance. Self capacitance and self resistance, temperature dependence of coil geometry and electromagnetic interferences affect the accuracy as secondary source of uncertainty. With respect of influencing parametres, the current transducer of aim accuracy can be realized.

E. Piuzzi, D. A. Lampasi, S. Pisa, L. Podestà
A VIRTUAL INSTRUMENT FOR TRANS-THORACIC IMPEDANCE INVESTIGATIONS

Impedance pneumography is a technique that allows the monitoring of respiratory activity through the measurement of variations in the impedance between two points located on the thoracic surface. In this paper, a low-cost, easily portable, and re-configurable measurement system is presented, suitable to perform impedance pneumography investigations, based on virtual instrumentation employing a data acquisition card controlled through a LabVIEW program. A possible approach for a metrological characterization of the system is proposed, showing a base uncertainty of the order of 0,4 % in the measurement of the resistive part of the impedance, in the range of interest. Some preliminary investigations have been performed in order to assess the influence on measured trans-thoracic impedance both of the kind of electrodes adopted for current injection and simultaneous voltage measurement and of the frequency of injected sinusoidal currents. Finally, acquisitions made on a volunteer are presented, evidencing the feasibility of the proposed system in monitoring the breath activity of a patient and in extrapolating relevant diagnostic parameters.

C. Ceretta, R. Gobbo, G. Pesavento
EFFECT OF INTEGRATION ERROR ON PARTIAL DISCHARGE MEASUREMENTS ON CAST RESIN TRANSFORMERS

Partial discharge measurements are routinely used for quality assurance of medium voltage resin encapsulated transformers. Instrumentation and procedures are covered by international Standards and measurements are in general reliable and reproducible. However calibration is performed at the winding terminals, whereas PD pulses are mostly originated well inside the coils: as a result, the shape of the signal being recorded can be very different, with marked oscillations. A comparison between different types of wide band PD detectors has been performed under conditions in which integration errors are experienced. It has been proved that when a PD pulse origin is located inside the MV coil of a cast resin transformer, the propagation towards the terminals can cause a marked distortion: the pulse harmonic content therefore cannot be flat in the frequency measurement range of the PD detectors and consequently the hypothesis upon which the pseudointegration principle is based is no longer valid.

Karol Korcz, Beata Palczynska, Ludwik Spiralski
MEASUREMENTS OF THE ELECTROMAGNETIC FIELD INTENSITY ON THE SEAGOING SHIP WITHIN THE FREQUENCY RANGE 0,1…30 MHZ

The method for measuring the intensity of electric and magnetic field with using of a system containing a set of measuring antennas and a spectrum analyzer has been described. A computer PC was used to analyze obtained results. The measurements results of the electromagnetic field intensity within the frequency range 0,1...30 MHz in the area of navigation bridge of the Gdynia Maritime University ship Horyzont II during her trip trough the waters of Bay of Gdańsk and water surrounding Hel Peninsula (Baltic Sea) are presented. They were carried out in 7 measurement points including a whole navigation bridge. During the experiment, all the standard devices present on the navigation bridge were turned on. The analysis of the obtained measurements results of electric and magnetic field intensities at all measurement points were carried out. The uncertainty of the obtained measurements of magnetic and electric field intensities is estimated. Furthermore, obtained results are compared to admissible reference levels found in available normative documents.

Septimiu Crisan, Ioan Gavril Tarnovan, Titus Eduard Crisan.
A HAND VEIN STRUCTURE SIMULATION PLATFORM FOR ALGORITHM TESTING AND BIOMETRIC IDENTIFICATION

Scanning the veins in human hands for biometric purposes has become more and more appealing due to inexpensive hardware requirements and rather simple software processing algorithms. However, there are few studies regarding the repeatability or uniqueness of the actual vein pattern. Furthermore, algorithm testing is usually carried out on a limited number of sample images acquired under different hardware setups. This is mainly due because of the lack of a vein pattern image database aimed to provide researchers with sufficient data to test recognition algorithms. Creating a large database of real hand vein patterns is a difficult task in terms of time and money. Other biometric domains, such as fingerprint recognition, benefit from synthetic generated images that greatly aid the accuracy of a given processing technique. This paper will offer a novel implementation of a platform for synthetic vein pattern images of the back of the hand. While the reasons behind pattern forming of veins are not completely known, there is sufficient data to create realistic images of vein patterns based on model reconstruction from crossing points, terminations and general anatomy of the hand.

M.Branzila, C.I. Alexandru, C. Schreiner
INTELLIGENT SYSTEM FOR MONITORING THE ENVIRONMENTAL PARAMETERS

The project’s idea is really simple: using the LabView environment, we have realized a virtual instrument able to get from the prototype data acquisition board for environmental monitoring parameters the information about air pollution factors like CO, H2S, SO2, NO, NO2 etc. In order to get effective information about those factors and the monitoring points, this intelligent measurement system, compound from portable computer, and Gas detector. This system can be used to map the information about the air pollution factors dispersion in order to answer to the needs of residential and industrial areas expansion.

M.Branzila, C.I. Alexandru, C. Schreiner
FROM REAL WORLD EXPERIMENT TO VIRTUAL LABORATORY AND NEXT GENERATION GRID

The Grid technologies are introduced to build e-Learning environments for engineering education. Service-oriented Grids open new fields of applications, the Learning Grids. The learning services concept based on a learning model and their deployment through Grid technologies are excellent means to integrate virtual laboratories into e-Learning environments for engineering education. The paper goes into the most important technical details, introduces into the used learning model, and shows the authoring of Grid resources for virtual laboratories. Examples from a virtual laboratory demonstrate the advantages of a Grid.

Marcus Tadeu Pinheiro Silva, Flavio Henrique Vasconcelos, Guilherme Augusto, Silva Pereira
RF INTERFACE FOR INTELLIGENT ARTERIAL PRESSURE SENSOR BASED IN RFID TECHNOLOGY

This paper presents an intelligent wireless sensors device developed to measure blood pressure and heart rate in small laboratory animals, employing an invasive (in vivo implant) method. This sensor relies on the RFID (Radio-Frequency Identification) technology to transmit and receive data. A mathematical measurement model is developed in order to obtain the measurand (blood pressure and heart rate) best estimate and the uncertainty.

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