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Purpose. In modern conditions of energy consumption growth and a rapid increase in energy prices the actual problem is the development and implementation of energy efficiency programs and resource-saving conversion in to a source to provide the needs of industry and municipal power. The paper aims to solve the urgent problem of energy saving and efficient use of fuel-energy ones and heat supply system optimization on the basis of Uman National University of Horticulture (UNUH). Methodology. The work investigated the process of heating and hot water supply in the course of 2007-2015 years. Implementation of current problems of energy saving is grounded on the scientific-practical and efficient assurance of fuel and energy usage. At the same time energy-saving technologies are viewed as a priority direction of the energy sector development, reduction of man-induced impact on the environment and as a way of improving the competitiveness of the national economy. Findings. Statistical data acquisition and analyzing of gas flow and outside air temperature for nine years was carried out. On the basis of this analysis, the problem was identified and specific targets for its solutions were set. Originality. Scientific novelty lies in solving the problem of energy saving and efficient use of fuel resources in Ukraine through the use of a systematic approach, the methodology development of efficient use of different fuels and optimization of local heating operation, applying contemporary automation and control systems. Firstly it was in detail analyzed and conducted the comprehensive assessment of various factors influence on energy conservation. It takes into account the human factor, professionalism and responsibility of the operators of boilers and their superiors, as well as the relevant control services. Practical value. For UNUH campus hybrid use of solid fuel and gas boilers was carried out. Decentralization of the university heating system has been conducted through the restoration of 350 individual heating systems in residential buildings, remote departments and campus dormitories. The conclusions propose the list of activities upon the real economy of fuel and energy resources, and measures to overcome the economic and political crisis in the country.

One of the most powerful modern methods of calculating complex building structures is the finite element method in theform of a displacement method for discrete systems, which involves the creation of a finite element model, that is, splittingthe structure into separate elements within each of which the functions of displacements and stresses are known. On the basisof the displacement method and the methods of iterations and half-division, an algorithm for stability calculation of the firstkind equilibrium form of compressed reinforced concrete columns with hinged fixing at the ends, considering the stiffnesschanging has been developed. The use of the above methods enables to determine the minimum critical load or stress at thefirst bifurcation and their stability loss corresponding form. The use of matrix forms contributes to simplification of high order stability loss equation. This approach enables to obtain the form of stability loss that corresponds to the critical load.

The paper represents the analysis, which has helped to establish the usage of gas hydrate technologies in the methane conversion. This gas could be obtained in different ways. Possibilities and sources for the gas obtaining have been demonstrated. Use of other environmentally friendly sources to support operation in such systems in terms of joint energy complex has been considered. The necessary kinetic connections to provide operational sustainability of all the constituents have been given. The approach helps evaluate quantitatively the priority of its physicochemical transformations to obtain gas hydrates artificially. It is possible to transport methane at considerable distances when it is solidified. Actually, in this case there is no necessity to build costly compressor stations and pipelines for its transportation to consumers. The approach is extremely important for mining regions as it helps prolong the operating period and working out of the abandoned and off-balance coal reserves. In this case, it is proposed to apply special gasification technologies tending to maximum methane recovery. The proposed solutions give the possibility to define the trends of our further research. They will be highlighted in the following authors’ studies.

Purpose.The railways of Ukraine have been operated the locomotives, which are both morally and physically obsolete. Therefore, to ensure the competitiveness of rail transport it is necessary to update the locomotive fleet, and first of all the fleet of electric locomotives, because electrified railways provide the greater part of passenger and freight traffic. In this connection it is of special importance to determine the optimum parameters of the nominal mode of electric rolling stock. The purpose of the work is to examine the features of solution of these problems with respect to electric locomotives. Methodology. Assuming that the limit values of traction force are determined by the conditions of wheel-rail grip, then the power of the nominal mode can be represented as the product of rated speed, estimated friction coefficient, train weight and the coefficients that represent the ratio of the estimated (starting) value of traction force to value of traction force the nominal mode and the ratio of the mass of the locomotive to the train weight. Since the mass of the train is not a constant value, there is always a surplus power of the locomotive fleet required for the mastering of a predetermined volume of transportations. Reduced overcapacity of the locomotive fleet can be achieved by introduction of the locomotives of different power, designed for driving trains of different weight that will result in increased completeness of the power use but also in difficulty in selecting of locomotives for trains in operation. The paper shows the method of calculating the optimum values of power, speed and traction force of the nominal mode. It presents the mathematical model of the relationship of traction rate, excessive capacity and power of the traction unit. Findings.It is proved that the power of the traction unit, the total fleet power requirement and the excess of power in absolute units are proportional to the speed of the nominal mode. To reduce the total power of the fleet when selecting the optimum power of the traction unit it is necessary to take into consideration the speed of the nominal mode, defined by the condition of minimization of power consumption for traction, i.e. the smallest value that enables the implementation of the given running speed and the powerredundancy level required for operation. Originality. It consists in the development of a unified algorithm for determining the optimal parameter values of the nominal mode of passenger, freight and freight-passenger electric locomotives. Practical value. The authors determined the minimization costs during production, acquisition and maintenance of electric locomotives, whose nominal mode parameters are designed according to the above procedure.

This article addresses the problem that fluctuations in the torque of an internal combustion engine (ICE) lead to additional energy losses, as it causes fluctuations in the speed and kinetic energy of the car. These losses increase as the frequency of oscillations of the torque of the internal combustion engine approaches the frequency of free (natural oscillations) of the running gear of the car in the longitudinal direction. If there is an elastic connection between the traction force and the movement of the car, the movement of the latter can be represented as complex. At the same time, the portable movement is uniform, and the relative movement is oscillatory. This article presents the results of the study of these losses for cars with mechanical and combined electromechanical drive wheels. Analytical expressions are obtained, which allows to take into account additional energy losses including the tangential rigidity of the tire and the rigidity of the suspension in the longitudinal direction. When using a combined electromechanical drive of the drive wheels as well as in the case of a mechanical transmission of a car, the resonance is dangerous. But with the increase in the share of torque kem on the wheel generated by the electric motor, the relative additional energy losses for the movement of the car are reduced.

In this article the following problem has been considered: ways of efficiency increase for electric drives installed at the railway machinery repair enterprises taking into account the specific conditions of technological processes.

Cross-ecosystem subsidies are important as their recipients often rely on them to supplementin situresource availability. Global warming has the potential to alter the quality and quantity of these subsidies, but our knowledge of these effects is currently limited. Here, we quantified the biomass and diversity of the invertebrates exchanged between freshwater streams and terrestrial grasslands in a natural warming experiment in Iceland. We sampled invertebrates emerging from the streams, those landing on the water surface, ground-dwelling invertebrates falling into the streams, and those drifting through the streams. Emerging invertebrate biomass or diversity did not change with increasing temperature, suggesting no effect of warming on aquatic subsidies to the terrestrial environment over the 1-month duration of the study. The biomass and diversity of aerial invertebrates of terrestrial origin landing on the streams increased with temperature, underpinned by increasing abundance and species richness, indicating that the greater productivity of the warmer streams may attract more foraging insects. The biomass of ground-dwelling invertebrates falling into the streams also increased with temperature, underpinned by increasing body mass and species evenness, suggesting that soil warming leads to terrestrial communities dominated by larger, more mobile organisms, and thus more in-fall to the streams. The biomass and diversity of terrestrial invertebrates in the drift decreased with temperature, however, underpinned by decreasing abundance and species richness, reflecting upstream consumption due to the higher energetic demands of aquatic consumers in warmer environments. These results highlight the potential for asynchronous responses to warming for reciprocal subsidies between aquatic and terrestrial environments and the importance of further research on warming impacts at the interface of these interdependent ecosystems.

The coupled instability of thin-walled columns with a preliminary local buckling is considered taking into account the overall initial imperfection, eccentricity of the compression force application and interaction of overall and local buckling modes.