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The classical concept of instantaneous frequency, obtained by differentiating the instantaneous phase is one of the most used approaches. Nonlinear signals usually have nonlinear and nonstationary behavior. Revealing hidden properties of time discrete signals could be important in understanding specific phenomena or processes. This paper uses simulated signals to prove the utility of instantaneous frequency estimation in dedicated signal processing. The procedure is based on empirical mode decomposition of the signal into monocomponents. The Hilbert transform of these monocomponents reveals they instantaneous frequencies. There are certain mathematical requirements and limitations for signals that the proposed procedure could perform proper instantaneous frequency estimation. The used signals are artificial and the procedure is carried out in MATLAB. [ABSTRACT FROM AUTHOR]

Induction heating performs contactless, efficient and fast heating of conductive materials, therefore became one of the preferred heating procedure in industrial, domestic and medical applications. During induction heating the high-frequency alternating currents that heat the material are induced by means of electromagnetic induction. The material to be heated is placed inside the time-varying magnetic field generated by applying a highfrequency alternating current to an induction coil. The alternating electromagnetic field induces eddy currents in the workpiece, resulting resistive losses, which then heat the material. This paper describes the design of a power electronic converter circuit for induction heating equipment and presents the obtained results. The realized circuit is a low power half bridge resonant inverter which uses power MOS transistors and adequate driver circuits. [ABSTRACT FROM AUTHOR]

The paper presents the tuning of a CMAC (Cerebellar Model Articulation Controller) regulator, with B-spline basis functions of order 3, implemented in an automatic daylight control system. After the tuning process of the regulator scaling gains, a set of ranges for scaling gains resulted. For these ranges of scaling gains the automatic lighting control system (ALCS) satisfied the desired performances. After the tuning process, the behavior of the ALCS in the presence of the illuminance disturbances was studied. At the final of the paper, an experimental tuning algorithm of the regulator scaling gains via ALCS step responses analysis is proposed. Even if the used experimental model of the process is a gross approximation of the real model of the process, using this experimental tuning algorithm, the designer can find a set of ranges of the regulator scaling gains for which the ALCS is stable and satisfy the desired performances. [ABSTRACT FROM AUTHOR]