Rares Iusan

This article studies the effects of the electrical arc on the electrical contacts situated in the automated fuse, where the thermal effect appears. A simulation of electrical contacts using Solidworks and Comsol with a comparison to the practical results has been carried out

For electroporation and bioimpedance measurements applications it is important to obtain information about the electrical distribution considering the different types of electrodes. This article will work strictly on blades of stainless steel electrodes. The simulations are realized in the Comsol program which uses different patterns of elements in methodical of electrical distribution of electrical field and electrical curents. In this paper, simulations and measurements will be performed to determine the applicability of blade electrodes for electrical model of the skin and electroporation. The results provide an overview of the distribution of electricity both in liquid medium and the solid medium for electroporation. To check the applicability of these electrodes, a customary electrical model of the skin will be used.

We report the bioimpedance measurements for human skin of the arm using ECG electrodes. A balanced rectangular signal (U= 1 V, f =5, 50, 500, 5000 Hz) was applied on a calibrated resistance, R= 10 k$\Omega$, in series with the two ECG electrodes glued on the arm of the human subject. The data were analyzed with a usual electrical model of the skin: a series resistance and one or more groups of parallel resistance with a capacitor.

The rhythm of rising food prices due to unjustified consumption of resources is a fairly pronounced problem and a technological optimization of greenhouses in which they are cultivated is necessary. The proposed automation system aims both to reduce production costs due to the efficiency of water consumption and the elimination of the human factor in certain maintenance and care works as well as the improvement of plant growth factors. Simulation of the system automation consists in the practical execution of a miniature greenhouse system with a scale of 1:10, controlled by a development board equipped with Arduino, temperature, humidity and light intensity measuring elements, modules for interfacing the microcontroller with the elements respectively the sprinkler water pump, the ventilation fan and the motors for opening and closing the ventilation hatch. The automation system can be applied and adapted to an authentic agricultural greenhouse irrespective of its dimensions, but taking into account the required power of the electrical machines.

In this paper the evolution of material loss belonging to an automated fuse, which is subjected to a short-circuit regime based on SR EN 60947-2 standard with 2-3 times the value of the nominal current is shown. The obtained results have been collected   within 11.05.2018 and the end of the year.

In this paper we verify if ECG electrodes are adequate for the bioimpedance measurement. A square wave signal (U=1V, f=5, 500, 5000 Hz) is applied to a calibrated resistance R=10 kΩ, in series with two identical ECG electrodes glued together by their adhesive part. Using an appropiate model, we find from the data a series resistance with one or more groups of a parallel resistance Ri with a capacitor Ci (i=1, 2, 3).

We measure nonlinear electrical properties of the skin-electrodes interface (i.e. voltage dependent bioimpedance), with voltages less than 2V for a sharper discrimination of the physical processes shaping skin-electrode electrical behavior as a main factor for designing new devices. A rectangular signal is applied through usual ECG electrodes on epithelial tissue with voltages starting from 0.2 V and a frequency of 500 Hz. The purpose is to determine the optimum value of electrical voltages in order to determine the electrical parameters of the tissue: parallel resistance (Rp), series resistance (Rs) and parallel capacity (Cp).