The paper considers an algorithm of average input signal value formation in microprocessor protection of electric installations distinguished by low sensitivity to changes in industrial frequency. The dependences permitting to give qualitative estimation of the considered method have been obtained with the help of a PC. 

The problems relating to an automation of measurement of magnetic characteristics of electrical-sheet steel have been considered in the paper. The paper investigates efficiency of an application of some well-known iterative methods for setting the required amplitude value of a magnetic induction of the material to be tested. It is shown that the most efficient method providing a fast and stable convergence of an iterative process while testing either textured or isotropic electrical-sheet steel is a parabola method.

The paper shows two approaches to mathematical modeling of split phase dancing of overhead electrical transmission line. The first approach is based on calculative method when a phase is in the shape of flexible elastic thread connected with rigid rods. The phase is represented with equivalent wire in the second approach. Principle of mechanics relations has been used to set combined boundary problem of split phase dynamics. Two packets of computer programs for calculation of split phase dancing of overhead (electric) power line have been set up and tested.

Investigations that were conducted with the help of overhead distribution line model reflected such situations as wire swinging cross, their contact with fallen trees and other earthed objects have shown that the overhead lines may operate rather long under such conditions. However leakage current may lead to dangerous high potentials on these objects and around them.

The results of calculations and experimental research have revealed that in the rain leakage current on an earthed object and insulation resistance depends on the width of moistened zone and practically does not depend on an object size and shape. Leakage current does not exceed 3 mA at an operating voltage and 15mA at possible internal overvoltage and full insulation resistance is not less than
3…4 MW for actual overhead distribution line spans.

The paper presents two systems of vector asynchronous electric drives that are invariant to an oscillatory load moment. Conclusions of the paper prove an advantage of the second system in comparison with the first one. 

Basic conceptual statements and «Delta» computer program complex for estimation and analysis of regimes, value, structure and confidence intervals of electric power losses in 6 … 20 kV electric networks have been developed on the basis of determined and probability-statistical models under conditions of various level of incomplete regime data and decision of dispatcher’s electric network problems.

The paper examines electric models of semi-conductor measuring converters. It is noted that main types of electric macro-models used for modeling multipurpose semi-conductor measuring converts should be considered approximate macro-models developed on the basis of a simplified initial circuit at a component level and formal macro-models based on formal approximation of external characteristics of multipurpose measuring converters.

The paper reveals a method for remote determination of a location of single-phase short circuit on the ground in distribution networks with isolated neutral point. The method is based on measurement of high-frequency (a tone  range) inter-phase voltage at all transformer substations and it creates preconditions for automation of searching process.  

It is proposed to use an exponential dependence for description of humidity distribution in cross-section of flat clay mass samples of plastic formation in an initial drying stage. Dependences of exponential curve indices on time from drying start-up and size of an «active» zone of clay mass dehydration have been determined. Analytical-experimental methodology for calculation of maximum permissible humidity differential of moulding mass under crack formation conditions has been developed on the basis of thermo-elasticity model. Some regularities for an estimation of thinning agent usage while making-up mixture.

Combined Thermal Power Plant unit is considered as an exergy generator. Exergy is supplied to consumers by streams of various power carriers. It allows to exclude division of the equipment and fuel consumption in product types and to propose extremely simple methods for estimation of the unit efficiency, calculation of power rate supplied from Thermal Power Plant bus bars and collectors.

Investigation results of hydraulic operational regimes of a circulating system with the help of a computer model are presented in the paper. The models simulates hydraulic processes by means of an iterated solution of a set of algebraic non-linear equations that is formed while using a graph theory The circulating system is considered as a unit in the model. The model program makes it possible to calculate consumption and pressure at any point of the circulating system with indication of flow motion directions along its separate branches and also to execute some economical calculations.

A kinetic model of natural gas burning has been developed. Calculated investigation of formation and reduction of nitrogen oxides at two-stage natural gas burning has been executed on the basis of the proposed model.

Analytical formulae for calculating simultaneous diffusion of two impurities in silicon are presented. The formulae are based on analytical solutions of diffusion equations that have been obtained for the first time by the author while using some special mathematical functions. In contrast to usual formal mathematical approaches, new functions are determined in the process of investigation of real physical models. Algorithms involve some important relations from thermodynamics of irreversible processes and also variational thermodynamic functionals that were previously obtained by the author for transfer processes. Calculations considerably reduce the time required for development of new integrated circuits. 

The paper presents a method for calculation of maximum fluid velocity in a process chamber that is installed with a gap relative to the surface to be cleaned while burning gaseous mixture composed of 2H₂ + O₂ in the chamber. On the basis of the analytical solution for the movement of unsteady-state flow of viscous incompressible fluid taking into account a number of assumptions an expression for calculating maximum stream velocity at the end of acceleration period is obtained. Action force of the fluid on the surface is calculated from a momentum equation.  An example for calculation of hydro-stream parameters is given in the paper.