The paper contains an algorithm for numerical experiment and computer modelling of ferroresonance and switching overvoltages having cumulative character and protection against these overvoltages. Possibilities of the proposed algorithm are illustrated with restriction of both overvoltages by means of a common device which is based on voltage supply to secondary winding of a voltage transformer from an auxiliary source of a switch-gear.

The paper presents one of the methods which is to be applied for investigation of the possibility to solve equations of steady-state modes (ESM) of electric power system (EPS).

The proposed method for investigation of ESM is developed on the basis of well-known Brauer’s theorem on a fixed point. In order to analyse ESM an inverted form of equations of nodal voltages has been used. These equations have been solved by iteration.

The areas of EPS mode existence have been obtained for 3-nodal circuit which is supplied by direct and alternating current. The analysis of EPS modes has made it possible to obtain the required conditions in order to prove the existence of ESM solutions.

The paper considers a model, a method and an algorithm of the simulation of the pulse system dynamics of phase synchronization in the multiple capture mode. Mathematical description of the devices is based on the method of space and state variables and makes it possible to take into account not only pulse and non-linear characteristics of these systems but also their various operational modes including multiple captures. The mode may operate either as secondary (parasite) or as main (operational) one. Necessity of the latter is caused by the fact that pulse systems using phase control principle are rather often applied at high or super high frequencies when realization of a divider with variable division coefficient which is set in the feedback loop is rather complicated or practically impossible. Multiple capture mode permits significantly to simplify the divider or exclude its application in the system. However designing of pulse systems of phase synchronization in multiple capture mode requires some additional research work and this paper is devoted to such investigations.

The paper reveals an application of force-moment sensors in manipulator control systems. Maintenance of contact between an object and a manipulator is rather complicated task and it does not have definitive solution. The paper contains mathematical description of various manipulator control methods with application of feedback force loop. Regimes of manipulator control are changeable in accordance with the problem which is to be solved.

The paper proposes an automatic system of fuel oil metering in vertical cylindrical tanks. The system makes it possible to execute continuous control over weight and temperature of fuel oil in a tank and metering of dead residue and initiates a signal system when fuel oil reaches an appropriate level in the case of filling. Nowadays the automatic weight control system of fuel oil has passed through metrological certification and is in operation at the Polotsk thermal power station. 

The paper contains the research results concerning changes of corrosive activity of combustion products of aqueous and fuel oil emulsions with various rate of water content in fuel oil. Data pertaining to determination of flows of sulphuric acid vapour condensation in chimneys at various regimes of their operation are given in the paper.

Results of 240 time determinations pertaining to investigation of surface cracking initiation on flat samples of moulding mass (80% of the Lukoml clay + 20% of granite screenings) of various thickness (1 ...4 cm) while being heated with intensive heat flow (~ 1 W/cm²) are given and analyzed in the paper.

It has been shown that under such heating conditions thickness of a sample practically does not make any effect on cracking intensity. At the same time determination of time indices concerning cracking initiation prior to clay mass treatment in the vacuum-press in accordance with K.Pirson’s criterion does not correspond to the normal law of distribution of random indices and corresponds to this law after processing in vacuum-press and moulding of air-dried bricks that makes it possible to predict with great reliability an output of qualitative products.

Determination of material exergy in a flow has been studied for asphalt concrete mix. Methodology for calculation of concentration component of asphalt concrete mix exergy has been proposed in the paper.

Model for calculation of combustion process of combustible foam flow which has been obtained by means of natural gas sparging of sewage water containing organic matter is proposed in the paper. The model makes it possible to determine factors that effect on changes in temperature profile of combustion zone and thickness of zone reaction.

The problems pertaining to the complex diagnostics of gas pipeline equipment operated by BELTRANSGAZ enterprise are considered in the paper. The importance of the matter is justified by the necessity of the stable and reliable power supply as to individual enterprises so to some entire branches of economy. This purpose may be reached only through trouble-free and safety operation of gas transportation facilities.