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AbstractFor the decision of significant power problems in Ukraine it is offered to improve ecological, economic, organizational and financial mechanisms of management in using of bowels and savings of resources on the basis of technologies on complex use of bowels (CUB) which introduction results in decrease in volatility of the country and reception of ecology-economic benefit. The principle of outstripping development of non-material actives before material is proved during development and realization of technologies CUB.

У магістерській дисертації розглянуто міжнародне співробітництво Україні в сфері енергетики. Висвітлено поточний стан розвитку міжнародного співробітництва у сфері енергетики. Визначено основні вектори роботи України в сфері міжнародних підходів до співробітництва в енергетичному секторі. В роботі сформульовано основі проблеми та вектори покращення реалізації міжнародного співробітництва у галузі енергетики України. Наведено пропозиції, які дозволять якісно покращити розвиток енергетики України за рахунок використання прийомів та методів міжнародного співробітництва.

This paper describes a bidirectional twisted single-phase single-stage buck-boost dc-ac converter based on an output unfolding circuit. This solution is derived by the combination of an inverting buck-boost dc-dc converter and an unfolding circuit. The operation principle, component design guidelines, along with the control approach are presented. The zero-crossing distortion problem is discussed and solved by a simple approach. The simulation and experimental results confirm all theoretical statements. Loss distribution and achievable efficiency are analyzed. Finally, the pros and cons of the proposed solution, along with the most promising application field, are analyzed and discussed in the conclusion.

The problem of torsion of a tubular belt on a straight route of a belt tubular conveyor (BTC) under the influence of stationary de-centering factors is considered. The effect of torques from uneven loading of the belt on the possibility of its torsion is investigated. It is shown, that the angle of rotation of the tape depends not only on the magnitude of the applied torque, but also on the design of the BTC, the geometric characteristics of the section of the tubular belt, the physical properties of its material. The effect of the coefficient of friction of the belt on the rollers on the possibility of its rotation has been investigated for various belt loading options with maximum irregularity. It is shown, that with a decrease in the load of the belt, the danger of its torsion increases. The boundaries, in which the coefficient of friction of the belt on the rollers must be found, are determined, so that the torsion of the belt does not occur.

In the surface mining of mineral deposits, land resources suitable for agricultural purposes are inappropriately spent in large volumes. When mining deep open pits, overburden rocks are mainly transported to the surface. The optimal solution for reducing the area of disturbed lands is the placement of overburden rocks in internal dumps in the open pit. This is especially suitable when mining a mineral deposit with several open pits where at least one of them is depleted. Therefore, it is important to assess the feasibility of building an internal dump, based on the stability parameters of its slopes and the safe distance for placing mining equipment within its boundaries, which was the focus of this research. Numerical modeling with Slide 5.0 software was used to determine the stability of the dump slope inside the open pit and the safe distance from the upper slope edge for placing mining equipment. This reflected the geomechanical situation occurring within the boundaries of the dump formed in the open-pit field with a high degree of reliability. It was determined that the maximum standard safety factor values of the open-pit slopes are within the limits when the overburden rocks border on the hard bedrock (Ks.s.f ≥ 1.2). Under the condition where the dump slope bordered on sedimentations represented by clays, loams, and sands with a strength of 2–3 on the Mohs scale, the safety factor decreased by 22%. It was determined that the minimum safe distance from the outer contour of the dragline base to the upper edge of a single-tier dump was 15.5 m with a safety factor of 1.21. The maximum safe distance values in the range of 73.5–93 m were concentrated within the boundaries of sections 5–9, with a safety factor from 1.18 to 1.28. When the dragline was located within the boundaries of section 7, the dump construction works should be conducted only if the dump exist for up to 3 years. Based on the identified parameters, on the example of using the ESH-11/70 walking dragline, a technological scheme of its operation was developed with the allocation of safe boundaries for its placement when forming an internal dump. The results obtained are useful for the development of projects for the reclamation of depleted open pits.

Метою дослідження є перевірка гіпотези правильності застосування показника Херста Н, розрахованого за емпіричним співвідношенням при значенні константи а, що дорівнює 0,5. Проведено ряд розрахунків показника Херста для декількох вибірок електроспоживання методом нормованого розмаху при значенні константи а, що дорівнює 0,5, які показали, що застосування емпіричного співвідношення для деяких вибірок електроспоживання призводить до великих похибок у визначенні цього показника. Запропоновано визначати значення показника Н або програмним шляхом (для вибірок, що містять більше 512 часових інтервалів n), або шляхом визначення методом найменших квадратів нахилу лінії регресії, яка утворюється з'єднанням точок, одержаних відкладанням по осі х а по осі у , де - нормований розмах.

To improve the strip rolling technology, it is important to know components of the thermal state of both the strip being rolled and the tool used, that is, rolls at each point of different layers of the strip and rolls, in any section of the deformation zone. It was established that for the numerical solution of thermal problems of heat transfer in the strip-roll system described by equations of unsteady heat conduction, the finite difference method is the most effective. For the further numerical solution of the problems of unsteady thermal conductivity of the strip and rolls during hot rolling, the sections of slabs and rolls were divided by a conditional mesh. Energy balance equations with subsequent finite-difference Fourier approximation for possible options of the mesh nodes occurring in solving the two-dimensional problem of unsteady heat conduction.When solving the heat balance problems for both the strip and the rolls, the performed transformations make it possible to switch from solving the nonlinear heat conduction problem to solving the linearized problem. It was also shown that when calculating the thermal state of the active zone in which cyclic temperature changes occur during one revolution, it becomes possible to switch from solving a problem in a cylindrical coordinate system to solving it in a rectangular coordinate system. Transition to solving a one-dimensional strip-roll system greatly simplifies the calculation. The solution of the III boundary-value problem for the roll and comparison of the obtained results with the results of solutions for the strip-roll system enables the theoretical determination of the heat transfer coefficient in the deformation zone.The study results can be used to determine temperature and speed mode of cooling a thin strip during its rolling as well as set tasks for designing special equipment for accelerated cooling in a production stream of strip rolling mills