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The results of acid tunneling on carbonate reservoirs of the Orenburg region for the increase of drainage area are considered. Weaknesses of the technology are considered, ways to improve efficiency are proposed. The technology made it possible to obtain stable increments of oil production at pilot wells.

There covered the characteristics of anesthetic management in trauma suffered by civilians during military conflicts (348 anaesthesis). Special attention is paid to organizational activities. A special focus is made on organizational aspects. It is demonstrated that the work optimization requires expediently the equipment of the shocking surgery of the medical admission unit and the operating rooms not only with the analgesia apparatus, but also with artificial pulmonary ventilation units, given that the essential method of anesthesia is the total intravenous anesthesia without anesthetic gas. The oxygen concentrators are advisable for the operating and intensive care units. It is necessary to know the presumable number of patients who can be attended simultaneously and to provide for the demanded quantity of medication and consumables. It is reasonable to have the kit assumed for one patient in the medical admission unit, where in most cases anesthesia as part of the complex intensive therapy is started.

The article describes the emergency care in massive injury during the military conflict (230 patients, of them 220 are civilian population, of them 7 are children; 348 cases of urgent anesthesia). Special attention is paid to organizational activities. Specifics of peri-operative provisions, intensive care are defined and given special emphasis.

This article shows the possibility of more effective control of an asynchronous motor with a squirrel- cage rotor than in the formation of an electromagnetic torque under flux linkage stabilization. A comparative analysis of energy properties of asynchronous machine operation under different kinds of control in similar conditions was performed. One means of control provides the premagnetization of the motor and creates electromagnetic torque upon stabilization of the rotor flux linkage in the first control zone, ensuring a transition into the second zone. In another means of control, in accordance with the developed method of sequential synthesis, premagnetization of the motor is not carried out, and at a low rotor rotational speed creates the electromagnetic torque with a minimum of total loss. When the speed increases, the electromagnetic torque is created under the stabilization of efficiency owing to reducing the reactive power in the function of the rotor-rotation speed. With a further increase in speed, the control is fulfilled with a minimum of reactive power, regardless of the motor load. The energy properties of the motor operation were compared depending on the load and rotation speed under the different means of control. The change in the energy properties of electric-drive operation when generating a motor angular velocity up to double the rate under conditions of limitation of voltage of the power-supply source was considered.

Background. The study of morphological, genetic and environmental factors explaining the subdivided (metapopulational) structure of habitats is a new and methodologically poorly developed scientific field. An important part of such research is the study of the genetic structure of animal populations. This scientific field is aimed at solving fundamental biological problems: the integrity of the biological species, microevolution and intraspecific differentiation, and population dynamics. The purpose of the work is to study the ecological characteristics of genetic polymorphism of Herb Field Mouse (Apodemus uralensis Pallas, 1811), Striped Field Mouse (Apodemus agrarius Pallas, 1771) and Yellow-necked Field Mouse (Apodemus flavicollis Melchior, 1834) mice in the Middle Volga region on the example of the Ulyanovsk region. Materials and methods. The genetic material for the work was collected in the Ulyanovsk region during field work over the period from 2014 to 2018. A total of 33 sequences (699 bp) of wood mice, 14 sequences (623 bp) of field mice and 9 sequences (700 bp) of yellow-necked mice were analyzed. For this, the MEGA 7.0.21 and DnaSP 5.10 software packages were used (Librado and Rozas, 2009; Tamura et al., 2012). In order to identify the environmental patterns of the distribution in the Ulyanovsk region of populations of the studied species of mouse-like rodents, except population groups obtained from data on their geographical proximity, we used two variants of zoning of the region under study- floristic and ecologicallandscape. Results. The highest level of variability of mitochondrial D-loop fragments was detected in A. flavicollis (2.4 ± 0.3%), while this indicator for A. uralensis and A. agrarius had average values (0.8 ± 0.2% and 0.7 ± 0.2%, respectively). Analysis of sequence samples by geographically selected population groupings did not reveal the corresponding genetic differentiation. Distribution of the identified mitotypes by population groupings does not have any pattern. Mitotypes found only in one of the groupings are present in the samples, and for this reason they are specific. The same results were obtained when analyzing the distribution of the identified mitotypes by floristic zoning of the Ulyanovsk region. The distribution of the identified mitotypes by landscapeecological regions reflects the ecological requirements of the studied species of mouse-like rodents. Conclusion. The results obtained indicate a good resolving power of the developed primer systems for amplifying D-loop and studying populational polymorphism of natural populations, as well as for grouping geographically separated populations of mouse-like rodents. The study of the distribution of the identified mitotypes of all three species of mouse-like rodents according to the floristic regions of the Ulyanovsk region did not reveal any connection between the floristic specificity of the territories and the distribution of these rodents in the region. This is probably due to the fact that the criteria for floristic zoning do not correlate with the biotopic preferences of the studied species. The distribution of the identified mitotypes by landscape-ecological regions, on the contrary, is in good agreement with the environmental requirements of the three species of mouse-like rodents. The D Tajima test for three species of mice in the Ulyanovsk Region indicates a possible increase in the number of their populations after going through the “bottleneck” during the period of population decline. This synchronization of demographic processes in populations of these species of mouse-like rodents is probably associated with a strong fragmentation of the habitat observed in the Ulyanovsk region, and high degree of subdivision of local populations of rodents.

The present work is devoted to the investigation of two-channel control algorithm of electromechanical vibration exciter that provides a free rotational motion of the unbalanced masses. A squirrel-cage induction motor was considered as a drive motor for the unbalance vibration exciter. Proposed control algorithm allows to start an induction motor without its premagnetization, as well as to provide a free rotational motion of the unbalanced masses in a quasi-steady state using vector control principles. Synthesis of the controllers for the control system was performed. Simulation modeling of the developed system was carried out in the MATLAB/Simulink software package, as a result of which system’s dynamic characteristics were calculated. The simulation results shows that proposed control structure allows to significantly reduce the copper losses for magnetization of the unbalance vibration exciter induction motor drive in comparison with the classical systems.

The energy properties of an alternating-current drive are analyzed. The suggested method allows us to compare in an analytical form the energy quality indices of various drives under different means of electromagnetic- torque formation in an electrical machine. Using the relation between power and energy characteristics as functions of the energy state, the energy efficiency, and intensity of energy-conversion processes, as well as the usage efficiency of voltage and power applied to motor windings, are estimated. By means of the constructed relations between quality criteria, the developed method allows one to determine at the stage of design the main properties of an electric drive under static and dynamic conditions. Using energy-state functions and arguments based on means of electromagnetic-torque formation, the method allows us to determine the thermal state at selection or testing of an electrical machine on the basis of heating or overload conditions.

The present work is devoted to the design of the energy-efficient control algorithm for an induction motor drive of an electromechanical unbalance vibration exciter. The control law under consideration consists in maintaining the direct and quadrature components of the stator current at the same level. Such an algorithm allows to minimize the effective values of the stator phase currents. A synthesis of the control system using this algorithm was carried out on the example of the selected induction motor drive. For the comparative analysis of the results, the control system for the electromechanical unbalance vibration exciter with the similar power unit and the constant reference of the rotor flux linkage was also synthesized. The dynamic characteristics of the developed systems were calculated in the MATLAB/Simulink software package. The simulation results showed the efficiency of the developed control algorithm for the induction motor drives of the unbalance vibration exciters.

Effective control of the electric machine should provide the best combination of dynamic and energy properties of the electric drive in the conditions of existing restrictions. These properties are contradictory, causing a complex (multicriteria) approach to the synthesis of control. An integrated approach to synthesis requires formalization of the control problem. The article deals with the rule of choosing solutions of multicriteria optimization, on the basis of which the problem of effective control of an alternating current electric drive is formalized.

The influence of the circuitry of the hybrid power plant short and medium haul aircraft on their fuel efficiency and environmental characteristics have been investigated. Directions of improvement of traditional patterns of power plants of aircraft on the example of PD-14 engine were analyzed. It has been shown that the use of turbojet engines and traditional schemes operating on aviation kerosene, will not allow to fulfill the demands made by the International Civil Aviation Organization (ICAO) to perspective plane 2025–2035. The analysis of the three schemes hybrid propulsion systems has been performed. It has been shown that using the presented hybrid propulsion systems of alternative fuels can reduce CO2 emissions by 19% to 20% compared with conventional turbojet engines, which run on kerosene TS-1. It has been shown that this fuel efficiency is increased by 2–3%, and the total mass of the power plant increases of 6 to 16%.

Today, when most reservoirs have low productivity, the question of whether hydraulic fracturing can be applied to the oil rims becomes very important. In such environment, the challenge of this widespread method of production intensification is significantly increased risk of gas breakthrough. Another challenge that is faced primarily during development of oil-rim (sub-gas) reservoirs is the selection of the most suitable completion designs. An outstanding example of oil rim stimulation was a project in Novoportovskoye field where an operator faced with a complex geological model of the reservoir characterized by an absence of strong clay bridges and minor contrasts in stress between interlayers associated with high risks of breakthrough into the gas zone. In 2016, the Novoportovskoe field operator successfully performed a 20-stage fracturing job. An innovative optimized multistage fracturing (MSF) solution was used that employed shifted closable fullbore sliding sleeves operated by coiled tubing (CT) intermittently with fracturing operations. This method was used for the first time in the development of the hydrocarbon deposits of the Yamal Peninsula and is based on the use of sliding sleeves that allow opening and closing of separate hydraulic fracturing ports. Such a design allows, in the course of further operation of the well, to cutting off or separating ports to prevent the inflow of water and gas, or, at the same time, to conduct refracturing of certain parts of the formation if required. This technology, which optimizes the fracturing process by utilizing shifted closable fullbore sliding sleeves/ports consists of the following: Reclosable CT fracturing sleeve (fullbore cemented sleeve that could be opened/closed an unlimited number of times)Openhole hydraulic packers to isolate zones in case of uncemented completionCT shifting tool (CT/tubing conveyed)Multistage mechanical packer (optional, could be used in case of inability to close one of ports). The resettable packer could be activated in any part of liner with axial CT movements; 10 000-psi rated. The main risk for hydraulic fracturing, in the absence of barriers is the proximity of the gas and water layers. Breakthrough of a hydraulic fracture into a gas- or water-bearing zone leads to a significant reduction in oil production rates. Stimulation operations in such difficult geographic and geological conditions have shown opportunities for the oil industry in the Arctic.

In this paper the control synthesis of asynchronous electric drive was considered. The proposed control algorithm provides a state change of the asynchronous machine with squirrel-cage rotor without magnetization in the minimum time within the limits set, at simultaneous regulation of a reactive power.

A two-channel system of stabilization of pressure in a fire chamber of a boiler unit is considered. Regulation of pressure is carried out by means of an automated electric drive by changing the speeds of rotation of the smoke exhauster and fan. It is suggested that smoke exhausters (the first channel of regulation) and fans (the second channel of regulation) be controlled. This increases the stability of depression in transitional regimes. It also reduces the time of transients and leads to a more efficient operating regime of the boiler unit. Regulators for the first and second control paths are synthesized. Synthesis is carried out by a modified modal method. The regulator of the first channel contains two components: a regulator of statics and a regulator of dynamics. It works in two regimes: established and transitional. The regulator of dynamics contains the regulator of the second channel only, and it works only in transitional regimes. This strategy allows not interfering with the main process of burning in the fire chamber of a boiler unit with quasi-established regimes. It also reduces the time of transients, when the process burning is not optimal. Regulation systems operating on one and two channels of influences are compared.

The possibility of movements' separation in the unbalance vibration exciter induction motor drive is shown in the paper. The unbalance vibration exciter induction motor drive control system has been synthesized on the base of the movements' separation principle. The digital simulation of the synthesized system has been conducted and its dynamic characteristics are presented. The advantages of the movements' separation principle as applied to the system under study are shown.

an asynchronous machine with squirrel cage rotor operation under combine control is investigated. That control ensure the formation of the electromagnetic torque, while the regulation of the energy properties of rotor speed function. Pre-magnetization of the magnetic system is not performed, that provide high energy efficiency of the electric drive operation and a performance of a control system in a linear dependence of an electromagnetic torque to a task. Control systems with stabilization of the rotor flux linkage have the same performance. Squirrel caged asynchronous machine model has the non-linearity of the magnetization characteristic.

Explore Job asynchronous machine with squirrel-cage rotor with the combined management, ensuring the formation of the electromagnetic torque in a simultaneous regulation of the energy properties of rotor speed function. Not completing magnetization of the magnetic system, it has been ensured pechivaya high energy efficiency of the electric drive, the performance management system, an electromagnetic linear dependence on the job, do not, differs substantially from the performance management system, with stabilization of the rotor flux asynchronous machine. Model squirrel cage takes into account the non-linearity of the magnetization characteristic.

In this paper the method of synthesis, that provided formation of cost-effective control of high-speed AC electric drive. Presented quality assessments allow you to associate the basic properties of electrical machine with control law.

The effect of polyacrylamide dissolved in water on the structure of a reflected shock wave in a gas-liquid medium is studied. Successive recordings are obtained of the behavior of a gas bubble behind a shock wave in water containing admixtures of polyacrylamide.

The problem of the automation of low-frequency unbalanced vibration modules is studied. The aspects of this problem which are covered in this paper are the calculation of the power of the drive for rotation of unbalanced masses of a centrifugal vibrator module, an analysis of the rigidity of the pneumatic matching device, and optimization of operating conditions of the electric drive for rotation of unbalanced masses. Control algorithms are formulated which optimize the operation of an electric drive rotating unbalanced masses. These algorithms can be implemented with standard computational technology or a digital computer.

The nature of the propagation of shock waves in various media is related to the characteristics of the latter, including their compressibility, thermophysical properties, the presence of multiple phases, etc. The structure of a shock wave varies appreciably as a function of the properties of the medium. The most significant property of a liquid mixture with gas bubbles is the compressibility of the latter under the influence of an externally applied pressure, for example, in a shock wave propagating in the liquid—gas medium. The transfer of momentum and energy between phases and the pressure variation behind the wave depends on the behavior of the gas bubbles behind the shock front.