Rational Mode Research Articles

WASTEWATER TREATMENT OF THERMAL POWER PLANTS (TPP)

An analysis of TPP wastewater, as well as technologies and equipment for their treatment, for choosing a rational mode and determining the maximum permissible concentrations of harmful substances characteristic of the energy industry before discharge into reservoirs was carried out. The compositions of the listed effluents are different and are determined by the type of thermal power plants (TPP) and the main equipment, its capacity, type of fuel, composition of the source water, method of water treatment, etc. For example, water after cooling turbine condensers and air coolers usually carries so-called thermal pollution, since its temperature is 8...10 ºС higher than the temperature of water in the water source. In some cases, cooling water can introduce foreign substances into natural reservoirs. In order to reduce the level of soil and groundwater pollution, local wastewater treatment facilities were constructed at thermal power stations. The second method is the collection of waste water in specially created containers with subsequent purification using sedimentation tanks and filters, which have anthracite or activated carbon as a filter material.
 TPP waste water is diverse and the chemical composition of each of the effluents is different. Wastewater treatment technology is complex and multi-stage and requires a large amount of various equipment.
 The ITTF of the National Academy of Sciences has developed a multi-purpose rotor-type aeration and oxidation plant (AORT), which works according to the method of discrete-pulse energy input (DPEI). This installation makes it possible to speed up the rate of heat and mass exchange of chemical reactions in water and water systems by 25-30 %. It makes it possible to reduce the duration of cleaning processes, reduce energy consumption by 2-3 times and consumption of reagents by 20-25 %. The AORT installation is used to clean sewage from iron, manganese, hydrogen sulfide, carbon dioxide, sulfates, and nitrates.

DEVELOPMENT OF BREAKTHROUGH TECHNOLOGIES FOR STRENGTHENING OF TURBO-EXPANSION INSTALLATIONS ELEMENTS

The paper is aimed at the development of breakthrough technologies for the strengthening of turbo-expander installations. For this purpose, new ways proposed for ensuring the strength of the most hardly loaded elements of turbo-expander installations. They involve a combination of known methods of discrete and continuous strengthening. However, at the same time, the problem of justification of rational parameters and modes of technological operations arises. This problem is caused by the fact that such complex strengthening methods are characterized by a significantly expanded set of varied parameters. In this wide parametric space, their optimal set differs from the optimal sets in narrower subspaces. To determine the influence of varied parameters on the characteristics of the stress-strain state of contacting discretely-continuously strengthened bodies, a number of studies were carried out. The shape of the strengthening area and the material properties of the strengthened zones are varied. A significant influence of varied parameters on the distribution and level of contact pressure and equivalent stresses in the system of contacting bodies has been established. Based on the analysis of the results of these and a number of other studies, recommendations have been developed regarding the design and technological solutions of elements of turbo-expander installations. On this base, a number of turbo-expander units with improved technical characteristics have been developed. In particular, the growth of their resource and efficiency have been ensured. Keywords: turbo-expander, discrete and continuous strengthening, contact interaction, stress-strain state, technical characteristics

Model of Influence of the Machined Material Properties on Wear of the Polymeric-Abrasive Tool Filaments

Abstract For polymer-abrasive brush tools (PABT) working on CNC machines it is necessary to correct their wear constantly, since it is much higher compared to the wear of metal tools. Based on the dependence of tool wear on machining parameters for various materials, it is necessary to study the influence of the physical and mechanical properties of the material machined. The purpose of the paper is to study the process of finishing the surfaces of parts made of materials of different types with PABT. The analysis of dimensional wear of disc PABTs during the polishing various materials with certain physical and mechanical properties is provided in the article. The polishing was carried out in rational modes that ensure high quality and productivity of surface treatment. The similarity theory and dimensional analysis were used to assess the influence of the properties of the material machined on the intensity of PABT filament wear. To calculate it, dimensionless complexes were established, which take into account the physical and mechanical properties of the machined materials and evaluate their resistance to the penetration of abrasive grains, the ability of the material to absorb mechanical energy in the process of deformation and destruction under the impact of PABT filaments. The developed model was created for the first time. It made it possible to solve the problem of predicting the degree of dimensional wear of the disc PABT when polishing various materials, including difficult-to-machine ones. Prediction of the intensity of PABT filaments wear allows timely correction of the tool position during machining on CNC machines to ensure a constant pressing of the PABT to the surface being machined. The obtained Км material coefficient takes into account the influence of the physical and mechanical properties of the machined material and then estimates the intensity of PABT filaments wear. The KМ material coefficient can also be used to assess the PABT life and calculate the economic efficiency of the parts finishing treatment at the stage of technology development and the selection of polishing tools.

Development of improved technology for the production of strong wines of marsala type on the basis of enzymatic catalysis

In the assortment of wines produced in the Republic of Azerbaijan, strong wines occupy a significant place. To improve their technology, a number of technological modes and parameters aimed at improving the quality of finished products and the use of modern technology were proposed and tested. As a result of the study, the effectiveness of the use of the mixed-action enzyme preparation Vinozim or Ultrazyme in the production of strong vintage wine of the Marsala type according to the blending scheme using the first must and press fractions was determined. It has been established that the use of this preparation in the process of fermentation of pomace provides a rational supply of phenolic substances for blends of marsala, and in the process of infusion of pomace of nitrogenous components and pentosis. The fundamental possibility of obtaining high-quality wine materials for vintage marsala under the conditions of processing grapes of the variety Bayan-Shirei and Rkasiteli "in the red way" has been studied. Rational modes for obtaining blended wine materials for Marsala, based on the technology of fermentation or long-term infusion of pomace, have been developed. The effect of various enzyme preparations on the quality of wine materials for Marsala has been studied; a rational variant of blending and aging of wine materials for Marsala was experimentally substantiated. It has been established that the rational option for obtaining vintage marsala is a blend of dry-fortified wine material and mistel, or dry-fortified wine material and vacuum must. Analysis of the dynamics of maturation of blended wine materials and data on changes in their chemical composition confirmed the choice of a rational scheme for their production and made it possible to establish the expediency of aging blends for marsala for 2.5 years. To improve the quality of ordinary marsala wine, a new technique for producing vacuum must was devised

METHODOLOGY FOR CALCULATING THE PERFORMANCE AND FUNCTIONALITY OF QUARRY EXCAVATORS

Conducted review of methods of calculation of productivity of open-pit excavators and results of verification calculations shows that, there is no uniform method that counts constantly changing physical and mechanical properties of developed rocks, technological parameters of a face, design and force parameters of an excavator, probability of its no-failure operation, casual character of transport delivery, qualification of the excavator operator, climatic conditions. Calculation of productivity of open pit excavators under specific mining and geological conditions is made for planning and rationing of excavation and loading machines, the choice and provision of transport, and establishment of a rational mode of their operation. In the given conditions of open-cut mining, an excavator’s productivity depends on many natural, mining-technological, and organizational factors, which are difficult to take into account and largely interact with the design parameters of open-pit excavators. In fact, most of the factors are probabilistic in nature. As a consequence, it is advisable to define values of productivity for each individual case based on the cumulative account of changes in multifactorial conditions of operation and technical condition of technologically connected equipment. In this regard, it is of interest to determine the value of productivity of quarry excavators with the account of the stated factors.

Investigation of Situational Correlations of Wire Electrical Discharge Machining of Superhard Materials with Acoustic Emission Characteristics

The purpose of this research is to find relationships between the parameters of the acoustic emission signals accompanying the electroerosive processing with a wire electrode of metals and hard alloys and the most important process indicators. These indicators include an increase in the concentration of erosion products in the interelectrode gap, an increase in the probability of wire electrode breakage, the efficiency of the supplied energy, the current productivity. This article presents the results of the study of acoustic emission signals during the processing of hard alloys with a cutting machine. The main focus is on the period preceding the breakage of the wire electrode. Changes in the parameters of acoustic emission a few seconds before failure are shown, and the possibility of preventing wire breakage by monitoring the parameters of acoustic emission signals is established. To evaluate the efficiency of the energy supplied to the processing zone, a dynamic model is proposed, with the help of which the processing efficiency is estimated by changing the transmission coefficients in one or several frequency ranges. To explain the situation that occurs in the processing zone with an increase in the concentration of erosion products, the article draws a parallel between electroerosive and laser processing, related to technologies of processing with concentrated flows of energy. Studies have shown that acoustic emission signals can be used to search for rational processing modes and improve automatic control systems for electroerosive equipment.

Mathematical Modelling of the Parameters of Braided Textile Tapes

Braided textile materials are widely used in many industries and agriculture. Braided tapes are used for domestic purposes, in the food industry, in construction, in medicine, in aircraft manufacturing, in electrical engineering, etc. Every braided product must correspond to a unique group of parameters and properties, depending on the initial manufacturing parameters. The production of braided tapes is still insufficiently explored. In the process of designing and manufacturing products with specified parameters, it is necessary to substantiate the formation of braided products. The manufacture of products with specific parameters and properties, and the creation of rational technological modes for that production represent urgent scientific issues to be addressed. One way to solve this problem is to conduct factorial experiments. This article thus presents the results of a factorial experiment, during which the following input parameters were determined based on preliminary studies: type of raw material, the linear density of raw materials and speed of removal of the product from the formation zone. The following were chosen as output parameters: breaking load, breaking elongation, the linear density of tapes, product width and the number of strands per 10 mm. The limits of factor variation were determined for four types of raw materials. Based on the results of the processing of the obtained experimental data, linear mathematical models were developed. The results of the verification of mathematical models indicated that they adequately describe the process of braiding tapes within the intervals determined by the conditions of the experiment. We thus established a connection between the factors of the braiding process and the properties of braided tapes.

ДОСЛІДЖЕННЯ ПОКАЗНИКІВ РОБОТИ ЦИКЛОНА-УТИЛІЗАТОРА З ВИКОРИСТАННЯМ CFD-ПАКЕТА SOLIDWORKS FLOW SIMULATION

It is shown that the use of solid biomass as a renewable energy source is relevant for the production of thermal energy and electrical energy. but the burning of biomass is accompanied by the release of a significant amount of ash into the environment. The need to organize the primary cleaning of waste gases of heat generators in cyclone dust collectors has been established. The stages of solving problems of aerodynamics and heat transfer in the SolidWorks Flow Simulation CFD package are described. The nature of the distribution of pressures, velocities of gas and solid particles in cyclone filters, the values of heat transfer coefficients in the flow area, based on which the studies of cyclone efficiency, hydraulic resistance, power of the heat exchanger-utilizer and the temperature of heated water were performed.It was established that an increase in the temperature of the inlet gas stream reduces the efficiency of the cyclone in cleaning highly dispersed ash, the presence of a heat exchange surface increases the resistance of the cyclone, but improves its efficiency in capturing solid particles up to 10 μm in size. The obtained results make it possible to improve the design, reduce the metal content, and find rational modes of operation of cyclones in operating conditions

Selection of parameters of the disc working bodies of the ripping-separating machine for soil treatment

Mechanical tillage with the help of a soil-cultivating ripping-separating machine is based on the combination of the operation of crushing and separating the soil along the depth of the cultivated layer. When moving the plowshare at a depth of 0.03–0.1 m, the movement of soil along the plowshare is complicated by the formation of an additional soil layer in front of it. To avoid this phenomenon, it is proposed to install passive freely rotating disks on both sides of the plowshare. The purpose of this study was to determine the most rational design parameters and modes of movement of disk working bodies. As a result of a theoretical study of the interaction of soil particles with the surface of rotating disks, the dependences of the thickness of the soil layer in front of the plowshare on the radius of the disk and the ratio of their rotation speed to the forward speed of the machine were obtained. As a result of experimental studies, the influence of the limiting distance between the disks and the angles of inclination on the thickness of the soil layer in front of the plowshare was determined.

Methodology for the control of electric power distribution system components to ensure the quality of consumed electricity

Electric power system is a complex organizational structure that provides working interaction for its constituent intelligent electronic devices by defining their roles, communication channels, and powers. The control system of a modern electric power system must ensure the coordination of operation of intelligent electronic devices at the technological stages of power generation, transport, distribution, and consumption. The disadvantage of existing process control systems in electric power systems is the use of a hierarchical control structure in relation to the network topology. This fact leads to conflicts of resources and processes at the stages of generation, transport, distribution, and consumption of electricity. Uncoordinated operation of control devices leads to a decrease in the efficiency of power facilities which negatively affects the quality of electricity in the power supply network. To synchronize the work of intelligent electronic devices distributed over the network, it is proposed to provide their joint work through a single information center in a digital environment. At the same time, it is proposed to control the modes of operation of the power supply network using digital twins of its components. Digital twins of electric power system objects control power quality indicators, simulate the modes of interacting devices in a digital environment, and perform control of power supply network components to ensure a rational mode of their operation. To achieve the universality and speed of the control system it is proposed to use the apparatus of fuzzy artificial neural networks, and for better prediction of power quality indicators in the network — ensembles of artificial neural networks. A methodology for controlling the quality of electricity at sections of the electricity distribution network was developed using digital twins that ensure the relationship between the monitored indicators of electricity quality and regulated values of the actuators of intelligent electronic devices.

Математическая модель процесса движения частиц рудного материала по виброоргану сепаратора

Introduction. One of the vibration methods for processing loose finely dispersed mineral raw materials is the separation method on a vibrating surface. Separation occurs according to size, shape of particles, coefficient of friction, elasticity and other mechanical parameters of particles. The efficiency of the separation process depends on the correct choice of technological characteristics of the working equipment. To solve such problems, mechano-rheological models are widely used. The issues of rational construction of research models, based on the specific conditions of the considered dynamic processes, are important and relevant. Materials and methods of research. Identification of rational parameters and modes of operation of vibration equipment is carried out experimentally or by mathematical modeling of the vibration process of the interaction of particles of mineral raw materials with the vibrating body of the separator. Mathematical models are developed for the separated components of the original ore material, which allow studying the dynamics of the movement of particles of the material along the vibrating body of the separator, and as a result of the research, the most rational operating modes of the equipment are determined. Research results and discussion. The presented mechano-rheological system as a model of a material particle is designed to study the processes of interaction with the working body of the separator, a mathematical description of the model is given. The model makes it possible to study the influence of the mechanical properties of the material (elastic, dissipative, plastic) on the dynamics of the process of movement of a material particle along the working body of the separator. For different stages of particle motion, models of different levels of complexity are recommended, which greatly facilitates the solution of problems for the development of algorithms and software for the vibration process under study. This increases the efficiency of the practical application of mathematical models in determining the rational operating modes of the equipment and evaluating the effectiveness of the vibration separation process. Conclusion. To study the process of vibrational separation at various stages of the movement of particles of ore material, it is recommended to use mathematical models of different levels of complexity. A mathematical description of research models for various stages of the vibrational process is presented, the conditions for the transition between the stages of particle motion are given. Resume. Thus, the presented mathematical model makes it possible to study the dynamics of the movement of ore material along the working body of the separator, taking into account the main mechanical properties of the material. The use of the developed recommendations increases the efficiency of the practical application of mechanorheological models for research purposes.

ПОЗИЦИЯ СТУДЕНТОВ МЕДИЦИНСКОГО УНИВЕРСИТЕТА К ЗДОРОВОМУ ОБРАЗУ ЖИЗНИ

Healthy way of life many-sided enough concept. Different people on it treat. For one is a refusal of bad habits, for others employment by physical culture and sports, for the third it is a rational mode of day and the balanced feed. Objective of our research was studying knowledge of students of medical university about a healthy way of life and aspiration to its introduction. Sociological interrogation by questioning 151 students of pediatric faculty has been lead. For this purpose, the questionnaire consisting of twenty-seven questions, which have been incorporated, in five sections has been created. During carrying out of research it has been revealed, that a healthy way of life connects 2/3 students with absence of bad habits, a balanced diet, a healthy dream and playing sports. The basic source of reception of the information on a healthy way of life was the Internet. Also consultations of doctors and the literature have noted been. A healthy way of life conduct half proquestioned, from them the majority do sports and on a regular basis and it is adequate eat. Among respondents non-smoking students prevailed, the use of alcohol with various frequency has noted been at 1/3 and basically only on holidays. Among students of the Centers health knowing about functioning only 2/5 are informed to the fullest on an orientation of their activity. Results of sociological interrogation have shown, that half of respondents take of a positive position to a healthy way of life as know about the given concept and adhere to it. But, availability of negative behavioral factors speaks about a negative position of other half of respondents.

Increasing the Wear Resistance of Restored Car Parts by Using Electrospark Coatings

The work scientifically substantiates the application of effective technology for the restoration of worn car parts by applying new electrospark coatings based on electroerosion nanomaterials. The developed technology is characterized by technological flexibility, cheapness, simplicity, does not require the use of expensive and scarce materials and equipment, and also meets the requirements of environmental safety. The proposed technology can be used to restore a wide range of parts for cars, tractors and other machines. Experimentally established dependences of the effect of the properties of electroerosive materials on the properties of electrospark coatings of restored car parts. It is shown that the content of nano-sized particles in the electrode material contributes to the improvement of the physical and mechanical properties of electrospark coatings. The dependences of the influence of the properties of electrospark coatings on the resource of restored car parts were experimentally established. It is shown that the resource of the shafts of turbocompressors restored according to the recommended technology is higher than the resource of new shafts by an average of 1.5 times. Experimentally established rational modes of applying wear-resistant coatings to worn shafts of turbocompressors, which provide the necessary complex of physical and mechanical properties of the coating and the given resource of the shafts as a whole (rotation frequency of the part, min - 1 - 50; electrode feed, mm/min - 0.4 ... 0.5). The characteristics of wear resistance of electrospark coatings of turbocompressor shafts, obtained using electroerosion nanomaterials, were studied. It is shown that the average value of the coefficient of friction of the electrospark coating was 0.146 instead of 0.486 without coating, which is 3.3 times lower. According to the results of production tests, it was found that the duration of operation of the turbocharger, with the restored method of electrospark treatment with a nanostructured electrode shaft, increased by 2.1 times compared to a new industrially manufactured shaft. Thus, when abrasive material containing a fraction of 0.1...0.4 mm was introduced, the operating time of the turbocompressor with a restored shaft was 12.8 hours, and the operating time of the turbocompressor with a new shaft without wear of the nominal size was 8.1 hours.

Влияние алгоритма управления на технические характеристики движения поездов

In order to choose locomotive control algorithm when prognosing train motion rational mode in an exploitation by the methods of mathematical modeling, the calculation was performed of main technical and economic characteristics of the operation of diesel locomotive 2TE116U with a stock at the use of full power and at control, basing on the parameters of a mode map. The method basis represents train motion dynamic model on a railway section with a given profile. To verify the de-veloped method, numerical studies were carried out in the wide range of changes of stock weights which not exceed the calculated weight. The obtained results have been compared with statistical data on the values of operational characteristics of train motion on Russia railways. It has been shown that train motion mode modelling at the use of locomotive full power gives a significant error at calculating technical speed, at the norm of train weight rate and fuel consumption and does not allow calculating locomotive control rational algorithm on optimization used criteria inclusive of op-eration conditions. At the choice of locomotive control rational algorithm, the necessity is substanti-ated for taking into account real conditions of train motion operation by batch or partially batch schedule which are reflected in mode map parameters.

МЕТОДИКА ВЫБОРА РЕЖИМОВ ФУНКЦИОНИРОВАНИЯ ПРИВОДА КАРЕТКИ ЗОНДОВОГО ОБОРУДОВАНИЯ ПРИ ПЕРЕХОДНЫХ ПРОЦЕССАХ. ЧАСТЬ 2

The article presents the results of studies, the analysis of which made it possible to identify features that affect the duration of the main periods of horizontal movement by the carriage drive with the object stage of the probe control equipment, the main of which include the mode of smoothness (dynamics) of movement and the accelerations associated with it during acceleration and braking, provided by the setting of the motor controller, as well as the step of displacement. It is shown that for specific inertia-stiffness and damping characteristics of the probe control equipment, the determination of accelerations for each mode of smoothness and duration of damping of mechanical oscillations after the carriage with the object stage moves to a given coordinate can be carried out in the debug mode of the probe control equipment or automatically using adaptive control. A method is proposed for selecting rational operating modes for the carriage drive with an object stage of probe equipment during transient processes using a database and a displacement step (of crystal size), which makes it possible for each smoothness mode to determine the cyclogram of its displacement and the total duration of the entire cycle, from which the minimum cycle is selected and implemented.

РЕЗУЛЬТАТЫ ИССЛЕДОВАНИЙ АЭРОДИНАМИЧЕСКИХ СВОЙСТВ ЗЕРНОВЫХ МАТЕРИАЛОВ

The aerodynamic properties of the components of the grain pile during its post-harvest processing are one of the most important parameters affecting the quality of the resulting grain and seeds. Existing devices are considered that allow establishing the speed of soaring of grain materials, their shortcomings and limitations are noted. A sail pneumatic classifier has been developed that provides smooth adjustment of the air flow rate and high accuracy of its measurement. Experimental studies have been carried out to establish polygons for the distribution of soaring speeds for a number of grain materials using the developed classifier. It has been established that the ranges of soaring speeds for different crops differ significantly. The soaring speed ranges for wheat and bindweed buckwheat do not intersect, which allows them to be completely separated using an air flow at a speed of 5.91-8 m/s. The soaring speed of sorghum (8.37-10.02 m/s) is completely covered by the range of this indicator for wheat, so it is not possible to separate them using aspiration systems. The ranges of critical rates of millet, vetch and wheat partially intersect, which indicates the impossibility of complete separation of these impurity components without loss of grain of the main crop. At an air flow rate of 9 m/s, 96.9% of the impurity component will be released from the wheat-millet grain mixture with technological losses of the main crop at the level of 4%. Even with a slight increase in the air flow rate, a significant increase in wheat losses is inevitable. Vetch can be completely separated from wheat at an air speed of 11 m/s with a loss of 1.8% of wheat. The results of the performed studies are necessary to improve the efficiency of the use of pneumatic separating equipment through the use of reasonable rational operating modes.

ОСОБЕННОСТИ ПРИМЕНЕНИЯ МНОГОКООРДИНАТНЫХ ШЛИФОВАЛЬНЫХ СТАНКОВ С ЧПУ ДЛЯ ПОВЫШЕНИЯ ПРОИЗВОДИТЕЛЬНОСТИ, КАЧЕСТВА И ТОЧНОСТИ ОБРАБОТКИ ДЕТАЛЕЙ И УЗЛОВ АВИАЦИОННЫХ ГАЗОТУРБИННЫХ ДВИГАТЕЛЕЙ

The paper is aimed at improving the productivity, quality and accuracy of manufacturing gas turbine engine parts and assemblies for the modern growing passenger aviation transport based on the use of technical capabilities of modern multiaxis CNC grinding machining centers. The paper shows the results of successful application of a five-axis CNC grinding machining center MFP-050.65.65 made by Magerle (Switzerland), which allows reducing by five times the number of operations, universal machines, special devices and cutting tools by increasing the number of machined surfaces for one set of nozzle blades of an aviation gas turbine engine. Simultaneously with a significant increase in the productivity of machining various multidirectional surfaces of the nozzle blades due to the use of new highly porous grinding wheels and rational modes of deep grinding, a higher burn-free quality of the ground surfaces is ensured and an important task is solved to increase the accuracy of the flow sections of the turbine nozzle apparatus with the combined use of CNC system and special software for correcting errors of part casting surfaces during their installation, turning and deep grinding of the base surfaces. The developed new technology of nozzle blades machining was introduced for the first time in the Russian Federation at the Aviadvigatel enterprise for manufacturing nozzle blades of modern newly produced gas turbine engines.

Экономическое обоснование режимов работы организационных человеко-машинных систем в растениеводстве

The article considers the feasibility study of the operating modes of organizational human-machine systems (HMS), using the price indicators of 2011. It turned out to be possible to substantiate the previously developed rational operation modes of organizational HMS with the help of the combined use of ergonomic and technical and economic criteria. The obtained results can be developed on the basis of the detailed account of the external environment parameters which require further study. Keywords: CROP ROTATION, HARVESTING AND TRANSPORT COMPLEX, OPERATION MODE, HUMAN-MACHINE SYSTEM, FEASIBILITY STUDY, MACHINE-TECHNICAL STATION, CROP PRODUCTION

Resistance, hegemony, and critical accounting interventions: Lessons from debates over government debt

Reflecting on how critical academics intervene in the public sphere, this paper explores how accounting is mobilized to reinforce and counter neoliberal hegemony in a public-policy debate over the role and size of government debt. The paper draws on the work of Gramsci, Laclau, and Mouffe to analyze case-data derived from three decades of media articles, research reports, and government financial documents in the Canadian province of Québec. The study finds that hegemonic actors seek consent from the population by exciting emotions (esp. fear and guilt), referencing the common sense, and aligning their arguments with people’s everyday experiences. While counter-hegemonic actors initially relied on conceptual reason and logic in their arguments, positioning accounting as an ‘ammunition machine’, they too came to adopt an approach aimed at exciting emotions, translating accounting concepts into non-economic fields, and rearticulating hegemonic signifiers, in an effort to refine and reshape the common sense. Highlighting the limitations of purely rational modes of argumentation, the study has implications for the manner in which accounting academics intervene in the public sphere and how they need to be skilled translators and re-articulators of hegemonic discourse.

Methodological Approach in the Simulation of the Robustness Boundaries of Tribosystems under the Conditions of Boundary Lubrication

In the presented work, a methodical approach was developed for determining rational operation modes of tribosystems, taking into account their design. This approach makes it possible in the designing stage, according to the predicted operating modes, to calculate the limits and margins of stable work in operation. The definition of the robustness of the tribosystem and the criteria for assessing the robustness are formulated based on the theory of stability of technical systems. It is shown that such a methodical approach allows for determining the modes of the rational operation of the designed structures without damaging the friction surfaces. Experimental studies have proven that not all designs of tribosystems lose stability due to the appearance of friction surface burrs. There are designs where the loss of stability occurs upon the appearance of accelerated wear. The developed criteria take into account two options for the loss of stability. An experimental verification of the modes of loss of stability of tribosystems was performed by the appearance of a burr or the beginning of accelerated wear with the calculated values of the robustness criteria. The obtained results allow us to conclude that the modeling error is within 8.3–18.7%, which is a satisfactory result in the study of friction and wear processes. Robustness criteria is based on the coefficient of friction RRf and wear rate RRI, and must be used when designing new constructions of tribosystems. Theoretical calculations of such criteria and the dependence of their change on changing the predicted operating modes will allow for justifying rational operating modes within their stability.