Predictive observation and real-time analysis of the values of biomedical signals and automatic detection of epileptic seizures before onset are beneficial for the development of warning systems for patients because the patient, once informed that an epilepsy seizure is about to start, can take safety measures in useful time. In this article, Daubechies discrete wavelet transform (DWT) was used, coupled with analysis of the correlations between biomedical signals that measure the electrical activity in the brain by electroencephalogram (EEG), electrical currents generated in muscles by electromyogram (EMG), and heart rate monitoring by photoplethysmography (PPG). In addition, we used artificial neural networks (ANN) for automatic detection of epileptic seizures before onset. We analyzed 30 EEG recordings 10 min before a seizure and during the seizure for 30 patients with epilepsy. In this work, we investigated the ANN dimensions of 10, 50, 100, and 150 neurons, and we found that using an ANN with 150 neurons generates an excellent performance in comparison to a 10-neuron-based ANN. However, this analyzes requests in an increased amount of time in comparison with an ANN with a lower neuron number. For real-time monitoring, the neurons number should be correlated with the response time and power consumption used in wearable devices.

A Z-source converter is an unique x-shaped impedance network called Z-source impedance network that couples the converter main circuit to the power source. The converter may be of all conversion types -if it is of ac-to-dc type, the z-source converter is called z-source inverter. Since 2003 when this recently conversion concept appeared [1], it proved able to solve many conversion problems. In this paper it's superiority compared to traditional solutions are shown. There are also small disadvantages and limitations revealed.

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For the equipment connected to the three-phase or single-phase grid, the power factor represents an efficiency measure for the usage of electrical energy. The power factor improvement through correction methods reduces the load on the transformers and power conductors, leading to a reduction of losses in the mains power supply and a sustainable grid system. The implications at the financial level are also important. An example of load that generates a small power factor is represented by a motor without mechanical load or having a small mechanical load. Given the power factor correction (PFC), the costs are reduced through the elimination of penalties, applying only in the common coupling point (CCP). The advantages of using equipment for the power factor correction are related also to their long operation duration and the easiness of their installation. The device presented in this article takes advantage of the advances in information and communication technology (ICT) to create a new approach for telemetry and remote configuration of a PFC. This approach has flexibility and versatility, such that it can be adapted to many loads, easily changing the capacitance steps and settings of the power factor correction device.