The work is devoted to the development of a new method for determining the demagnetization curve of high-coercive permanent magnets, for example, magnets made of NeFeB alloy. It is expected that the new method will make it possible to more accurately determine the demagnetization curve of permanent magnets by using voltage and current meters instead of class induction sensors, which will avoid the accumulation of error that occurs when integrating a signal from induction sensors. The paper describes in detail the algorithm of the new method for determining the demagnetization curve, provides references to the methods and algorithms used in the development of the new method. The method was tested on a multiphysical model of a permanent magnet and a magnetizing installation built in the COMSOL Multiphysics software package.

Keywords: permanent magnet, neodymium magnet, highly coercive material, magnetic material, Fourier-Bessel decomposition, approximation, momentum, optimization, simplex, Nelder-Mead algorithm, mathematical model, coercive force, hysteresis

This article describes methods for measuring the characteristics of drinking water using microwave technologies, provides their comparative characteristics, advantages and disadvantages. The advantages of research by resonance methods are shown, the prospects for their application for further research are shown. Dielectric constant of substances, its influence on resonance.

Keywords: microwave technologies, resonant and non-resonant methods, water purification, drinking tests, dielectric constant