The results of studies reflecting the state of environmental safety at the global and regional levels over the last 3 years are reviewed. The mutual influence of environmental and economic problems is noted; since economic security is a vital human interest, it is an integral part of environmental security at all economic levels. It is assumed that great progress in further research can be expected in the use of environmental safety provisions in the field of economics and economic modernization of the general theory of environmental safety.

This work is devoted to the development of a new method for modeling information systems of multi-criteria design, based on expert ranking of criteria. The possibilities of the fuzzy-set theory and the possibility theory allow for a comprehensive analysis of criteria by reducing numerical indicators to a qualitative form, passing to the corresponding fuzzy relations of preference. Some of the information may be lost, therefore conclusions should be applied, both on the basis of “quantitative” processing of the results of measuring the criteria, and on the basis of “qualitative” processing. If these conclusions coincide, then their adequacy will be confirmed based on the initial data. Since the modeling of complex design systems is determined by several criteria defined on different base sets, and the problem of determining the multi-criteria efficiency in conditions of incompleteness of the initial data remains relevant, within the framework of this article, an optimization method is proposed simultaneously according to many criteria with incompleteness of the initial data. The difference between the described method lies in the fact that the expert ranking of criteria enables to formally set fuzzy preference graphs that make it possible to obtain comprehensive information about estimates in the rank scale during pairwise comparisons, with the aim of subsequent search for Pareto-optimal solutions in multi-criteria problems.

The technique for constructing a thermodynamic model of chemical transformations that occur in ecological systems, which can be used to study the course of ecology, is proposed. The information necessary for students studying environmental disciplines for the independent implementation of thermodynamic calculations is presented.

The paper addresses the issues of stepless speed control of the hydraulic drive output link by means of frequency control, throttle control and pump-throttle control; they are compared, and their applicability in various types of hydraulic drives is analyzed [1, p.619]; a mathematical model of losses arising in a volumetric rotary hydraulic machine with volumetric (pumping) control and frequency management is given; a mathematical model is formed on the basis of which the dynamic characteristics of removable hydraulic drive with frequency control with varying parameters of external load and operating factors will be studied. The paper is based on theoretical research of the frequency-controlled hydraulic drive that was carried out [2, p.41]. As a result of the research, a schematic solution and a mathematical model of the developed hydraulic drive have been proposed. The main structural and technical and economic indicators are: a change in the angular velocity of the rotor of the machine in a given range, and an increase in the energy efficiency of the drive.

The methodology for experimental measurement of the shunting current has been developed in the article. Upon reaching a certain depth of immersion of the filler wire into plasma due to an increase in the potential difference between the end face of the wire and the surrounding plasma, the shunting current is significantly increasing reaching several dozen amperes. By changing the immersion depth of the wire by changing the value of the shunting current, it is possible to control the heat input into the base and filler metal, as well as to manage the transfer of the filler metal.