9762 papers found
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.
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...
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...
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...
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...
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...
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...
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, H 2 S, SO 2 , NO, NO 2 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...
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...
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.