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The relevance of the study is due to the fact that in the conditions of the financialization of the economy, shocks arising in one market can spread rapidly and intensively to other markets, generating the effects of financial contagion. This fully applies to the commodity markets, which occupy a large share of exchange trading. The resulting excess volatility risks should be taken into account both by financial market players when developing optimal portfolio strategies, and by the state when adjusting anti-crisis policy. The purpose of the study is to identify financial contagion in commodity markets during periods of financial stress caused by the pandemic and sanctions, to determine the direction and extent of intermarket contagion. The novelty of the study lies in the construction of stress indices to separate periods of increased volatility in commodity markets, in the application of statistical tests for the co-moments of the return distribution to identify the financial contagion between the markets of energy (oil and gas), precious and non-ferrous metals during the pandemic and sanctions. The result of the study is the identification of a period of increased volatility in commodity markets and its division into two sub-periods based on turning points in the stress index, establishing the direction and extent of financial contagion between commodity markets during these periods. It is concluded that stress in commodity markets is accompanied by intense financial contagion. Moreover, volatility contagion turns out to be higher than return contagion and even higher than contagion caused by anomalies in the return distribution. The main sources and receivers of contagion in different periods are the markets of precious and some non-ferrous metals, and in the period from February 2018 to December 2020, also the oil market. At the same time, the gas market before SMO has demonstrated relative independence from other commodity markets, which made it possible to recommend gas futures as a tool for hedging investment portfolios during a period of increased financial stress.

Introduction. Aluminium alloys are characterized by the absence of a cold fracture threshold, have high strength and ductility characteristics at low temperatures. However, the norms do not provide the design of aluminium structures that take cyclic force effects at low temperatures. In this regard, there is a need to study the properties and mechanisms of deformation and destruction of aluminium alloys to assess the possibility of their use in the Far North, as well as well as for the inner shells of isothermal reservoirs.Materials and methods. The mechanical properties of structural aluminium alloys 1915, 1565ch and 6082 (similar to AD35) were studied. The specimens were tested for uniaxial tensile strength, impact toughness and fatigue strength, and the characteristics of static crack resistance were determined. The tests were carried out using Instron 8802, Instron 1000HDX, LabTex machines and Instron 450 MPX pendulum coper according to the relevant GOST standards of Russia.Results. Experimental dependences of strength and elastic characteristics (tensile strength, offset yield strength, modulus of elasticity), as well as deformative ones (relative elongation and contraction of the cross-sectional area of specimens) of the studied alloys on the test temperature are obtained. The change of character of deformation of aluminium alloys with decrease in temperature is shown. The results of deformation and fracture resistance under conditions of impact bending and eccentric tension in the temperature range from –104...+20 °C are presented. Fracture toughness (crack resistance) was estimated according to the criteria of fracture mechanics when testing standard specimens with fatigue cracks. The paper also shows the limited limits of endurance based on 2 · 106, 107 cycles of the studied alloys at positive and negative temperatures.Conclusions. The obtained results make it possible to reasonably select materials, assign loads when designing structures made of aluminium alloys and evaluate their service life.

The possibility of applying the method of multistage loading (Lokati) is considered for the calculation and experimental evaluation of the contact endurance limit. The results of applying the Lokati method to determine the median contact endurance limit of specimens made of aluminum alloy Д16 (D16) and 0.45% carbon steel are analyzed. The tests were carried out according to the scheme “shaft — roller” in rolling conditions without slipping. The criteria for reaching the limit state, the parameters of the multistage loading mode were varied. It is shown that the Lokati method and its basis, the hypothesis of linear accumulation of fatigue damage, make it possible to satisfactorily assess the value of the contact endurance limit of the studied materials.

For the implementation of a mixed type of transportation on the territory of Ukraine, a stable saddle for transporting cargo semi-trailers without a tractor on railway platforms of the 13-9004M model was developed and manufactured. This device for the transportation of cargo semi-trailers is a four-sided structure of the "Eiffel Tower" type, the lower plane of which is fixed on the platform car through the plate with the help of bolted connections. This work describes the running tests of the 13-9004M model platform car with a saddle rack installed on it for the transportation of cargo semi-trailers without a tractor. According to the results of the tests of the saddle rack for the transportation of semi-trailers on the platform wagon model 13-9004M, the maximum values of the stresses that occur in the structure of the saddle rack during running strength tests, as well as compliance with such indicators as the coefficient of vertical dynamics of the sprung mass of the cart, the coefficient of vertical dynamics of the unsprung mass, were determined trolley frame, coefficient of horizontal dynamics, coefficient of reserve of stability of the wheel from derailment.

Existing methods and equipment for determining the dynamic characteristics of devices and systems are considered. A new method for estimating the dynamic error of navigation devices is proposed. It makes it possible to simplify the experimental assessment of the dynamic error of serial products as well as to evaluate its value under conditions of real disturbing influences corresponding to operating conditions using test equipment. The method is based on the measurement by the device of pseudo-random test effects reproduced by the stand in a given frequency spectrum corresponding to the operating conditions of the instrument. In this case, the variance of the dynamic error of the device under study is determined as the area under the graph of its power spectral density. To implement the method, it is proposed to use a specialized stand that allows to reproduce oscillations in a given frequency spectrum. The results of the application of the developed method in solving the problems of estimating the dynamic errors of the electronic inclinometer are presented. The results of experimental studies are consistent with the results of field tests obtained earlier. The developed method makes it possible to reduce the time for estimating the dynamic error of sensors and devices to 15–20 minutes because it does not require measurements at each frequency separately, and also allows to evaluate the error of devices in real modes of its operation.

This publication presents the specialists’ experience of Nizhny Novgorod State Technical University n.a. R.E. Alekseev (NNSTU) in the field of studying the friction-rolling of an automobile wheel on an asphalt surface. Adequate mathematical reproduction of force reactions that occur in the contact patch plays a significant role in modeling vehicle dynamics. Since the fundamental description of this interaction is difficult, in engineering practice the empirical method has become popular, which consists in obtaining an experimental data array with its subsequent trigonometric approximation and systematization. NNSTU specialists have developed a test methodology and carried out full-scale tests using a specialized road tire trailer bench. The experiment was carried out on a dry asphalt pavement with a coefficient of adhesion of about 0.4–0.8 at an ambient temperature of 20 °С. The resulting array of experimental data is processed and presented in the form of a trigonometric digital model PAC 2002. The maximum discrepancy between theoretical and experimental data in absolute value doesn’t exceed 5 %.

The article is devoted to solving the actual scientific research task of confirming the design extended period for replacing engine oil for the advanced automobile diesel engine of the KAMAZ R6 family. The main goal of scientific research is to improve of consumer properties and efficiency of vehicle operation by increasing the frequency of their maintenance. The solution of the problem within the framework of this article is to assess the performance of a particular brand of modern high-tech engine oil from long-term operation and determine the period for its replacement in engines of the KAMAZ R6 family. The methodological apparatus for solving this problem was based on the developed algorithm for allowing motor oils to be used in KAMAZ engines. Based on the results of a complex of laboratory, bench and operational tests, the performance of the Lukoil Avantgarde Professional ACEA E4 / E7 SAE 5W-30 engine oil in the KAMAZ R6 family engines was positively assessed, and the declared replacement period of 150 thousand km was confirmed. The scientific novelty of the results obtained lies in the fact that new specific dependences of the quality indicators of modern high-tech engine oil Lukoil Avantgarde Professional ACEA E4 / E7 SAE 5W-30 on long-term operation during bench and operational tests of the KAMAZ R6 family diesel engine have been established. The theoretical value for the development of the branch of science “Operation of road transport” lies in the fact that the identified patterns contribute to the study of the efficiency and quality of operating materials, the patterns of changes in characteristics, performance indicators, the determination of consumption standards and rational service life of operating materials. The positive effect of this is the improvement of the processes of organizing the maintenance of vehicles, which helps to ensure their operational reliability and increase the efficiency of operation. The direction of further scientific research is the solution of the following complex problem - to investigate the patterns of consumption of engine oil and changes in the technical condition of the diesel engine of the KAMAZ R6 family from operating time to justify the optimal frequency of vehicle maintenance.

Background. The object of research is existing and prospective spacecraft. The subject of the study is the control of the technical condition and diagnostics of the onboard equipment of spacecraft. The aim of the work is to develop a model of an intelligent monitoring and diagnostics system, the use of which will increase the reliability of determining the technical condition of the onboard equipment of spacecraft at the stage of their testing and application. Materials and methods. When developing a model of an intelligent system for monitoring and diagnosing the onboard equipment of spacecraft, the main attention is paid to a method based on machine learning, which allows you to build predictive models using both retrospective and current data received in real time from measuring equipment and obtain patterns that are not obvious at first glance. Results. An approach is proposed to increase the reliability of determining the technical condition through the use of an intelligent system for monitoring and diagnosing the onboard equipment of spacecraft. The intellectualization of this system is determined by the presence of mathematical, algorithmic, software and instrumental components of intellectual support for decision makers in the management of spacecraft. Conclusions. The developed model of an intelligent system for monitoring and diagnosing the onboard equipment of spacecraft makes it possible to expand the capabilities of the spacecraft by implementing the functions of correcting the algorithms of the onboard and special software based on the results of machine learning and neural network processing of television measurements, contributing to a more reliable determination of the technical condition of the onboard equipment. The proposed model is proposed to be used at the stages of testing and application of spacecraft to increase the reliability of determining the technical condition of on-board equipment and the efficiency of taking measures to prevent the occurrence of emergency situations.

Repeated impact testing is an important part of any product development. The tests are carried out on stands of repeated blows. In order to expand the range of functional parameters of mechatronic stands of multiple blows, the following are proposed: criteria for choosing the parameters of an air suspension, a method for predicting changes in the stiffness of a shaper during stand operation, and a method for assessing the effect of the reproducibility of controlled parameters on the stability of a shock pulse. In contrast to the known works, the proposed criteria and methods take into account the requirements for the reproducibility of the shock impulse.

Background. The object of research is the processes of development, testing and intended use of existing and promising space assets. The subject of the study is ways to improve the quality of functioning of automated control systems during state tests of samples of space assets. The aim of the work is to develop a decision support system that allows automating the process of parrying emergency situations when testing promising samples of space assets. Materials and methods. When developing a decision support system, the main attention is paid to the formation of a structural scheme of the database and the possibility of using the method of reasoning based on precedents. Results. An approach to the implementation of a decision support system using a mechanism of reasoning based on precedents in the expert diagnostics system is proposed. This approach makes it possible to monitor the technical condition of space assets in a timely and more qualitative manner and makes it possible to make adequate decisions in order to resolve problematic situations. Conclusions. The developed decision support system helps to reduce the information burden on the official in the decision-making process, to reduce the influence of subjectivity factors in analyzing the current situation, to increase the efficiency of decision-making at the stage of testing space assets while monitoring their technical condition. The proposed device is proposed to be used to automate the processes of test analysis and operational search for the resolution of abnormal and emergency situations when testing promising space assets.

The article presents studies carried out in 2018–2019 and 2019–2020 in the southern foothill zone of the North-West Caucasus in the fields of the selection and primary seed produc- tion department of the Adygh Research Institute of Agriculture. The aim was to study the actual, biological or potential yield of winter soft wheat varieties cultivated in the region, as well as the ratio of the mass of the grain part and the harvested straw - the yield index. The studied varieties were divided into groups according to plant height: semi-dwarfs (up to 90 cm), short-stemmed (up to 105 cm), medium-sized (up to 120 cm). According to the results of the studies carried out, differences in the studied characteristics were revealed. In the group of semi-dwarf varieties, the grain yield varied from 7,25 to 8,05 t/ha, short-stemmed 7,78–8,91 t/ha, medium-sized 7,34–9,60 t/ha. The highest grain yield was shown by the Vekha variety (9,60 t/ha) belonging to the group of medium-sized varieties, from the short-stemmed Maikopchanka varieties (8,91 t/ha) stood out, Kalym semi-dwarf varieties (8,05 t/ha). The biological yield in the experiment varied from 9,37 to 15,29 t/ha. From semi-dwarf varieties, Grom stood out (14,06 t/ha), short-stemmed varieties – Mafe (10,8 t/ha), medium-sized varieties – Vekha (15,29 t/ha). The difference between the actual and biological grain yield of varieties belonging to the short-stem group was the smallest in comparison with the varieties of the semi-dwarf and medium-grown group. On average, over two years of research, the harvesting index was 46,9–53,2%. Semi-dwarf winter wheat varieties had the maximum value of this indicator. In the group of short-stemmed Grom and Graf varieties, the ratio of the mass of the grain part to the harvested straw varied from 46,8% (Velena) to 50,5% (Alekseich). The harvesting index for medium-sized varieties was at the level of 46,9–51,8%. The Vekha variety, which showed the maximum value, stood out from this group.

The article analyzes relationships of the non-uniformity of the initial states and the lifetime of friction pairs and tribo-fatigue systems based on the results of the inspection of the technical condition after operating time and laboratory tests. The non-uniformity of the initial states is determined by the variation within the tolerances of the geometry of the elements due to the manufacturing technology, and its influence on the wear rate, dynamic characteristics and lifetime of mechanical systems is estimated on the example of automobile sliding friction bearing pairs and rolling bearings. A laboratory experiment to assess the performance of a model of a tribo-fatigue system “shaft (steel 45) — roller (25ХГТ (25KhGT) steel)” due to local violation of the shaft geometry during rolling is analyzed. The correlation equations are given that link the integral characteristics of the local process of wear-fatigue damage, based on measurements of the circular contour of the test specimen (coefficients of asymmetry and non-uniformity), with the relative number of cycles until the limiting wear of the tribo-fatigue system “shaft (steel 45) — liner (silumin)” under sliding friction is reached.

Background. The relevance of the use of high-voltage voltage dividers in information-measuring systems is determined by the wide use of high voltages in various fields of human activity. The control of high voltage pulses necessitates the use of broadband voltage dividers. The purpose of the work is to familiarize with the modern domestic high-voltage voltage divider DNV-20I and the results of its tests. Materials and methods. Scale transformation method. Results. The description and test results of the voltage divider DNV-20I are given. Conclusion. The high-voltage voltage divider DNV-20I corresponds to the declared data and can be used to control and measure DC and AC circuits, as well as impulse voltage.

The article considers the challenge of studying the mechanical properties of composite sandwich constructions at the interface between the base layers and the lightweight core. The results of strength tests are presented for specimens of sandwich-core panels with coats made of high-strength carbon fiber-reinforced plastics (CFRP) and polymer honeycomb core considering various loading conditions. It is noted that a discrepancy in the values of shear stresses occurs in four-point bending and shear tests due to the complex stress-strain state of the specimens during bending. In order to interpret the experimental data, numerical analysis of the area of contact interaction between the coats and the filler of the sandwich-core composite structures is carried out. It is noted that in the presence of significant normal stresses in the adhesive coat the base layers separate from the core during shear tests and there is underestimation of the values of shear stresses by about 20%. Recommendations for the assignment of ultimate shear stresses for the use in practical design of sandwich-core composite constructions are put forward.

Introduction. When carrying out an energy assessment of agricultural machines and traction tests of tractors, the most important indicator is the value of the tractive effort. The existing methods for determining the tractive effort of tractors imply the use of specialized measuring instruments, such as strain gauges and devices for processing and displaying information. The accuracy of determining the tractive effort is significantly influenced by the physical and mechanical properties of soil. To process the useful signal during the measurement of tractive effort, the data stream of the strain gauge sensor must be subjected to additional digital filtering taking into account the operating conditions of the agricultural unit. Materials and Methods. The functions of changing the tractive effort obtained on the K-744R2 tractor in various gears have been analyzed. An algorithm for digital processing of the signal of a strain gauge force meter based on a median filter has been developed that makes it possible to increase the measurement accuracy. The advantage of the proposed method is the ability to cut off sharp short-term impulse noise and sharp fluctuations in the amplitude of the measured value. Results. A method for determining the amount of tractive effort using median signal processing has been proposed. A device for determining the tractive effort during testing of agricultural tractors and units has been developed. The choice of the main components of the device for determining the magnitude of the tractive effort has been substantiated. As a result of the research, a device for measuring and digital processing of the signal of a force meter based on a microcontroller and specialized software for processing initial data in real time was designed and manufactured. Discussion and Conclusion. The developed method makes it possible to exclude the negative effect of impulse noise arising in the process of measuring the tractive effort of the tractor. The proposed device for measuring the tractive effort of tractors is compatible at the level of the exchange protocol with existing devices, has a high speed of operation in real time, multi-channel operation.

The article highlights the historical improving of students` educational achievements monitoring process in maritime educational institutions in 1990-1999 of the XX century. Orders, reports, meetings of methodological associations and pedagogical meetings and other documents, the content of which is related to the educational activities of maritime educational institutions in general and monitoring, are analyzed. There was an urgent need for state monitoring of the education quality. Reforming the education ofUkraineand monitoring the academic achievements of students in maritime institutions in practice was associated with the emergence of testing and rating system.

The article is devoted to the study of the problem of spontaneous combustion of energy grades of coal not only during storage, but also during transportation. As the main samples for the study, the energy grades of SS and Zh coals were selected. The main task of the scientific research was to study the rate of cooling and heating of coal depending on their thermophysical parameters and environmental parameters. To solve this problem, the authors used both the author's installations designed to study the thermophysical parameters of the spontaneous combustion process (the Ya.S.Kiselev method), and the NETZSCH STA 449 F3 Jupiter synchronous thermal analysis device, the NETZSCH Proteus Termal Analysis software package. On the basis of a complex study of the spontaneous combustion process, the authors of the article obtained the kinetic characteristics of the spontaneous heating process (activation energy and pre-exponential multiplier). Nomograms of the permissible size of coal density of different types and shapes of accumulation depending on the ambient temperature are presented, practical recommendations for the prevention (avoidance) of spontaneous combustion of coal fuel are given.

In the modern oil industry, the vast majority of oil production units are represented by sucker rod pumping units, driven mainly by asynchronous electric motors without using any monitoring, control and regulation means. Studies carried out on such installations show their low energy efficiency and reliability. Therefore, the issue of developing complex electric drives of a new generation based on the use of synchronous valve electric motors is relevant allowing to significantly increase the energy efficiency and reliability of both individual installations and to ensure the creation of "smart" oil field control systems. The paper discusses new technical solutions of the experimental stand which makes it possible to study the energy characteristics of electric drives based on asynchronous and synchronous valve electric motors, as well as allowing to create conditions as close as possible to real field conditions with imitation of the operation of an oil pumping unit of a sucker rod pumping unit. In modern test equipment systems, devices are often used to create a mechanical load on the shaft of the electric motor under study. The system proposed and implemented as such a device is "a frequency converter – load asynchronous electric motor", which has been tested on a stand and has proven to be the best in comparison with traditional circuits using DC motors. But using of a load asynchronous electric motor as part of the test stand has revealed a number of disadvantages: overheating of the electric motor operating in the opposing mode, low accuracy of creating the load torque and the speed of the system's response. The problem of overheating of the load electric motor has been solved by transferring the frequency converter to the direct torque control mode, while a significant decrease in the motor current and stabilization of the temperature regime have been detected. The low accuracy and response speed of the system have been increased by introducing feedback and a PID controller into the stand control system.

The article presents an approach to formalizing the process of creating a system for providing temperature, air supply and filtration (TAFS) of transported control modules of aerospace defense complexes. The use of line graphs to control the creation of such systems has recently shown its inconsistency and requires improvement in terms of how to manage the processes of creating such systems. As a basis, it is proposed to use the dynamic theory of graphs, which allows one to take into account not only resource-time constraints, but also possible changes in the structure of relations of sequences of work performed to create TAFS. The paper shows that the key element of managing the process of creating TAFS is a complex modeling stand, which can be used to obtain objective data on the development of system equipment. The availability of this information allows taking control on the process of creating TAFS at all stages of the life cycle using a network model. The composition and structural diagram of such a stand are given in the article

The article considers the problem of assessing the stability of the continuously welded track at its temperature elongation and proposes a method for this assessment by comparing the actual temperature of fastening the rail strings with the standard one. A method for determining the actual temperature of rail fastening is presented, which consists in measuring its temperature and natural vibration frequencies, followed by an analysis of the dependence of the change in the natural frequency of the rail head in the transverse direction on the magnitude of the longitudinal force applied to the rail. The methodology of the tests performed at the bench and section of the continuously welded track of the Ozerskaya branch of the Moscow railway is described. The essence of the technique is to determine the values of natural vibrations using various measuring instruments (strain gauges, vibration transducers, sound level meters) at different values of the longitudinal force applied to the rail. Natural vibrations were excited by hitting the rail head in the transverse direction. A comparative analysis of the forms and frequencies of natural vibrations of the rail head is carried out according to the test results in bench and operational area conditions. It was found that the closest convergence of the vibration frequencies of the rail head in the transverse direction corresponds to the first mode of vibration. During bench tests, the dependence of the frequency change of the first form of natural vibrations of the rail head in the transverse direction on the magnitude of the longitudinal force applied to the rail was determined. According to the results of a comparative analysis of the results of measurements of the natural frequencies of rail oscillations, the possibility of using a sound level meter or similar measuring instruments for their registration was established. The calculation of the actual temperature of the rail fastening is also given on the example of the section of the continuously welded track of the Ozerskaya branch of the Moscow railway and its compliance with the normative for this region is established.

Introduction Total hip arthroplasty (THA) is one of the most successful orthopedic procedures performed today. Rates of THA have been steadily increasing over the past several decades with increasing number of patients who need proper effective rehabilitation therapy after orthopaedic surgery. Evaluation and introduction of new rehabilitation techniques is crucial for patients undergoing replacement of major joints. Objective Review the literature and our own findings with various rehabilitation programs used for THA patients to aid recovery following surgery at a short and long term. Material and methods The study included 57 THA patients referred to rehabilitation department of the Kurgan Ilizarov Center to help manage pain at different terms following surgery. The sample was divided into main (n = 29) and control (n = 28) groups. Post-isometric relaxation techniques were included in rehabilitation program of the main group. Clinical outcomes were evaluated with VAS, the Lequesne Index, McGill Pain Questionnaire, WOMAC, and Harris Hip Score. Results Outcome measures showed 1.5 times improvement in controls with high statistical significance (p > 0.01) and 3.3 times improvement in patients who received post-isometric relaxation therapy with greater significance level (p > 0.001). Conclusion The findings suggest that post-isometric relaxation techniques applied as a part of restorative treatment facilitate improved outcomes of rehabilitation. The optimal rehabilitation protocols have been shown to be largely unknown for THA patients.

The development of non-destructive testing methods for power equipment including methods of thermal imaging diagnostics is relevant in view of the tasks set for implementing the concept of "Digital Transformation 2030". The paper provides a review and theoretical analysis of the problems that arise during the quantitative thermographic diagnostics of electrical equipment. On the example of analysis of the thermal imaging tests of heating a contact compound during electric current flow, the advantages of the method and the disadvantages of the existing approaches have been considered. It has been shown that with the existing recommendations for processing thermal imaging tests, in particular, "RD 34.45-51.300-97. Scope and norms of testing electrical equipment", forecasting and expert assessment of the thermal state lead to significant errors. The data of numerous diagnostic parameters taken into account in the process of thermal imaging diagnostics have been evaluated, namely: current load, geometric and thermophysical parameters of the object and the environment, emissivity, wind speed and others. Taking into account the electrophysical parameters of an object, the features of its structure allows for an adequate expert assessment and data reduction to a single criterion; this makes it possible to compare the results of various tests, to accumulate a data bank, the prospect of which is to calculate reliability indicators and recommendations for improving the technical base of power engineering. The similar approach headed by the analysis of quantitative data accumulated during thermal imaging tests, and a comparative analysis of the data of other diagnostic methods, will make it possible to implement and expand the capabilities of the method when developing digital technologies.

The high cardiovascular morbidity and the use of modern research methods in practice, the high demand for functional research with the workload growth of specialists due to modern requirements, including the work with medical documentation, indicate the need for organizational changes.Aim. To identify organizational problems of functional medicine practitioners work and determine ways to solve it.Material and methods. Using descriptive statistics, the analysis of federal statistical observation № 30 “Data on medical organization” was carried out. It characterizes the work of functional medicine practitioners in subjects of the Russian Federation in 2012-2017, as well as their photo and time tracking research.Results. The data of federal statistical observation showed that the lowest workload of practitioners was noted in the North-West Federal District, where the growth in the number of testing procedures per specialist occurred by 14,5%. To a lesser extent, this parameter increased in the Central Federal District — by 12,6%. The Volga Federal District takes the second place: the number of testing procedures increased by 21,8%. The highest growth was noted in the Siberian Federal District. By carrying out photo and time tracking research, the weighted-average costs of working time for conducting functional tests are established taking into account the type of test. It will help to reduce the burden of specialists.Conclusion. The results of the study showed an increase in the number of functional tests by 15,9%. A higher burden in the work of functional medicine practitioners was noted in the Penza Region, the Chukotka Autonomous Okrug, the Republic of Ingushetia and the Kirov Region. The formation of document on the norms of time for conducting functional tests, based on the results of photo and time tracking research and its implementation will help to reduce the burden of specialists.

This paper presents a variant of using an artificial neural network (ANN) for adaptive learning. The main idea of using ANN is to apply it for a specific educational material, so that after completing the course or its separate topic, the student can determine, not only his level of knowledge, without the teacher’s participation, but also get some recommendations on what material needs to be studied further due to gaps in the studied issues. This approach allows you to build an individual learning trajectory, significantly reduce the time to study academic disciplines and improve the quality of the educational process. The training of an artificial neural network takes place according to the method of back propagation of an error. The developed ANN can be applied to study any academic discipline with a different number of topics and control questions. The research results are implemented and tested in the CATS adaptive training system. This system is the author's development.

An experimental study of the influence of the rms value and the broadband parameter of the random load on the durability of the elements of the products is carried out. According to the test results, the dependence of the durability on the broadband parameter is proposed. The accuracy of the correspondence of the data calculated by the proposed dependence with the experimental results is evaluated.

The article presents the control and measurement materials (CMM) for the discipline «Theory and technology of development of mathematical representations in children.»CMMs are presented in the form of tests.

The results of research on increasing the efficiency of a firing test facility for testing thrusters under high-altitude conditions are presented. The increase in efficiency consists in reducing the expansion pressure generated by the ejector and the flow of the active gas (air) consumed by it. Experimental studies were carried out using three versions of gas generators developed by the author which ensure an increase in the energy of the active gas before it is supplied to the ejector. When using the GG-1 gas generator with working media such as air, kerosene and water, the vacuum of less than 1 mm Hg was achieved with the air mass flow rate of 1.1 kg/s (the ejector provides a vacuum of 13 mm Hg with the cool air flow rate of 2 kg/s). However, the design features of the gas generator led to a cumbersome system of supplying working fluids and a complicated start-up sequence. The GG-2 gas generator with air and kerosene as working media failed to provide the temperature of the active gas below 600°C, therefore, to prevent ejector malfunctioning, GG-2 was turned off when the rarefaction reached 13 mm Hg. The air mass flow rate was 1.1 kg/s. The working media of the GG-3 gas generator are air and kerosene or air and natural gas. The design of the GG-3 makes it possible to regulate the temperature of the produced active gas. When working on kerosene, a vacuum of 4 mmHg was reached with the air mass flow rate of 1.5 kg/s. The studies of GG-3 using natural gas as a fuel are going on.

Introduction Total hip replacement and total knee replacement are one of the most commonly performed orthopaedic procedures and available assessment tools designed to measure functional outcomes are widely discussed in the literature. Organization and assessment of results of restorative treatment are important issues of total joint arthroplasty. The objective of the study was to evaluate functional status of patients after THR and non-operated subjects with coxarthrosis using scales and tests accepted as quality of life measures. Material and methods Clinical and unctional status (pain intensity, impairment of limb function) was evaluated in 151 THR patients and non-operated coxarthrosis patients using WOMAC, VAS, Harris Hip Score, the Lequesne Index and McGill Pain Questionnaire. Result THR patients showed less pain intensity and stiffness as compared to controls (p < 0.05) with no significant differences in severity of functional disorders before and after THR (p > 0.05). Conclusion The findings suggested that deficits in function in THR patients required rehabilitation interventions at different postoperative time points.

Monitoring student learning is an important part of the educational process at a higher education institution. One of the means of modernizing control and analysis of learning outcomes is the computerized testing system. The application of testing has become widespread in various areas of human activity. The introduction of testing at Ukrainian educational institutions contributes to the integration of Ukraine into the European educational space. Among the advantages of using computer tests to assess academic achievement of students is to increase the level of objectivity of the assessment, the possibility of a profound analysis of the results of available quantitative indicators, the possibility of mass evaluation with significant time saving to verify the results. However, tests in the educational process are used not only as a means of measurement, but as a means to achieve various pedagogical goals. Tests help identify gaps in the study of learning material and encourage learning, thus contributing to the development of students with the required competencies. The periodic use of tests allows to form feedback between teachers and students for effective correction the learning process. The methodology for organizing the research was the author's technique. The experiment used a questionnaire (before and after the experiment), testing (before and after the experiment). The publication argues the proposed version of the construction of a computer test system. The step-by-step algorithm allows anyone wishing to create their own system of test tasks. In the formation of tasks, the taxonomy of Bloom was used, on the basis of which three levels of complexity of test questions were developed. There have been conducted the analysis of existing copyright test systems; its results have been used when creating the author's system. The test system has been tested in higher education institutions and approved by faculty and students. Levels of mastering the educational material are determined. The results of the study of the level of usefulness of the tests and readiness for their use in the educational process allowed to take into account the wishes and disadvantages of creating a test system.

This paper provides an approach to the possible application of mathematical-model research in geomechanical tests. In addition, specific geomechanical laboratory tests were performed on a granite sample. After that for these tests, mathematical-model research was done in order to replace the modeling of physical-mechanical research. The laboratory material is crushed, classified and it is calculated the volume mass in the natural state and in the loose state (after crushing). Also, 3D model has been prepared with the reconstruction of images from the real model. Then, from this 3D model, using the DEM (Discrete Element Method), is made a model of particles (pieces), that replace the crushed material. On this model are analyzed some physical-mechanical characteristics. A comparative analysis defines the difference between actual laboratory and modeled results. [ABSTRACT FROM AUTHOR]

The article analyzed the approaches to the concept of «meritocracy». The article determined that the meritocratic principle in the selection of management personnel is revealed in the early selection of talented individuals who have managerial abilities, charisma, high level of intelligence, communication abilities, and are honest, responsible, unbiased with their own personal core. The author noted that the principle of meritocracy in the formation of a management elite is manifested in equal access to the system of public administration of all professionally trained persons with a high level of moral qualities that have been appropriately selected and have experience in management activities. The article analyzed the experience of forming a managerial staff in Singapore. The success of the Singaporean model of public administration is based on meritocratic principles, a strict bureaucratic hierarchy and administrative impartiality, and is based on four major strategies: Singapore’s comprehensive civil service reform; strong and effective anti-corruption measures; decentralization of the Civil Service Commission; payment of competitive wages to attract and retain the best personnel. The author identified the main stages of selection of management personnel in accordance with Ukrainian legislation. In our opinion, the meritocratic principle should be central to the formation of the national managerial elite through the prevailing system of qualifying tests, examinations on the basis of objective, impartial and comprehensive evaluation.

The article deals with problematic issues of assessing the strength of axisymmetric parachute systems in flight tests. One of the main tasks in preparing for flight tests is the choice of conditions for carrying out an experiment. Variants of parachute system breakdown tests are considered. Loads occurring in parachute system inflation are analyzed. The specific character and peculiarities of parachute damages and failures are presented in the article. The problem of parachute system destruction under breaking loads considerably smaller than the parachute load bearing capacity is posed. We propose to use methods of experimental optimization and stochastic approximation to reduce the number of experiments. The conclusion is drawn on possible ways of solving the problem of assessing the breaking load and load bearing capacity obtained in assessing the strength of parachute systems in a flight experiment.

It is shown that the intensive threshing mechanism, containing the drum with smooth rasp bars an d the concave with a convex inlet and canting bars with flanges (_/ - shaped bars) without rods throughout the remaining exte nsion, may become more effective with fuller allowance for mechanical - and - physical properties of the threshed m aterial. The changeabi lity of the classical space geometry between rasp bars under the resistance reduction of the concave is proved. The laboratory tests and test - use of the intensive threshing mechanism are resulted.

Purpose: to substantiate the relevance of standardization of the process of conducting military (research) tests, to determine the quantitative characteristics of criteria for assessing the quality of standards for physical training of servicemen of the Armed Forces of Ukraine. Material & Methods: analysis of the relevance of the issues of standardization of the process of developing, organizing and conducting military (research) tests, determining the quantitative characteristics of the criteria for assessing the quality standards for the physical training of military personnel used in developed countries and in Ukraine. Results: discusses the importance of standardization of documents on the management and organization of physical training in the Armed Forces of Ukraine, reaching eligibility standards PP armed forces – NATO members. Suggested content standard. Conclusion: urgency of creating a standard in conducting military tests of physical training exercises for servicemen and units of the Armed Forces of Ukraine has proved the need to achieve criteria for compliance with the standards PP of the armed forces – NATO members countries. The lack of a regulatory framework makes it difficult to organize and carry out research and development work, operational tasks to develop new standards of physical training for the Armed Forces of Ukraine.

Copyright of Yearbook of Banjaluka Law School / Godisnjak Pravnok Fakulteta u Banjaluci is the property of University Banja Luka, Faculty of Law and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study describes the Information and Communication Literacy Test (the ICL Test), an instrument to measure information and communication technology competence in middle school students (grades 7–9). An overview of the existing instruments proves that there are no other ICT competence assessment instruments applicable to Russian students today. The assessment was constructed using an innovative systematic approach (evidence-centered assessment design, ECD). The ICL Test results were calculated using Bayesian networks, which are more effective than the Item Response Theory in this case. The ICL Test revealed a high level of construct, content, convergent, divergent and face validity as well as good reliability. The instrument conforms to both Russian and international educational standards according to Webb’s criteria for alignment. The ICL Test results were used to assess ICT competence and identify the factors that influence its development in regions of Russia, Armenia and Belarus. The conclusion is that the ICL Test can be applied to both Russian and foreign education systems.

The article shows the relevance of work on the development of components and models of vehicles with hybrid and electromechanical power units. A brief description and results of the stages of the traction-dynamic calculation, selection of components, layout, assembly and initial testing of the prototype of the Belarusian electric vehicle are presented. The results of the work show the potential of Belarusian developers in the field of creating advanced drive systems based on electrical components and modern technical level control systems.

In recent decades, the use of constructed sleepers on the world's railways has been increasing: the United States, the EU countries, Japan and China. Such sleepers, having positive performance qualities of wooden sleepers (good elasticity and dielectric properties, manufacturability during laying and during repair work), do not have negative qualities of wood. The article reviews the US and EU standards for testing sleepers made of constructed materials. The classification of such sleepers is given. Examples of testing of such sleepers by specialists of JSC “VNIIZhT” for the period from 1999 to 2016 are given, including sleepers from modified wood, wooden sleepers with elastomeric coating, composite sleepers from recycled high-density polyethylene with glass-filled polymer. Features of the Russian requirements to the constructed sleepers are considered. Composite rail seat supports are promising in application. Possessing the advantages of wooden sleepers (bars), they have higher wear resistance, lower life cycle costs (recyclable), are more homogeneous and do not rot. Damping properties of composite sleepers contribute to solving the problem of reducing noise and vibration from rolling stock. In addition, their use is one of the ways to reduce the negative impact of rail transport on the environment. With a feasibility study, such sleepers will successfully replace other types of rail seat supports. Spheres of rational application of composite rail seat supports are heaving sections of the railway track, areas with weak soils, turnouts, tracks on bridges, railway tunnels, and underground tracks. Taking into account the tendency to expand the polygon for laying composite sleepers, including railway tracks, metro routes and land transport in the Russian Federation, Kazakhstan and other CIS countries, it is advisable to develop a single interstate standard containing safety requirements and test methods for constructed rail seat supports.

The results of calculated-experimental researches of life-time with reference to service conditions of thermonuclear installation parts on the basis of methods of classical cyclic strength and tribofatigue (taking into account frettingeffect) with the use of specimens from zirconium bronze are given. It is displayed that the effect of contact impacts with reference to the complicated and responsible parts of considered installation of the tokamak type in the range of room and heightened temperatures and in corresponding loading conditions is exhibited in decrease of cyclic strength. Thus the life-time defined for the examined material on smooth cylindrical specimens in the homogeneous stress state conditions, at the presence of contact impacts is reduced that can be considered in the corresponding coefficient defined experimentally.

In December 2016 at the Test Loop of JSC “VNI-IZhT” comparative testing of four types of ballastless track designs (BVSP) - LVT (RZDstroy, Russia), FFB (MaxBögl, Germany), NBT (Alstom, France), EBS (Tines, Poland) - have been completed. The passed tonnage for the pilot section of the four structures was 600 million tonnes gross. The article analyzes the intensity of settlement of the ballastless track and in transitional sections under the train load. Conducted tests of four types of ballastless track designs LVT (RZhDstroy, Russia), FFB (MaxBögl, Germany), NBT (Alstom, France), EBS (Tines, Poland) and earlier tests of the Rheda (RailOne, Germany) design showed that for the ballastless track on the subgrade, the most critical are not the stresses in the structural elements, but the values of the vertical settlements. In the places of maximum values of the settlement of the upper bearing concrete (reinforced concrete) slab, the underlying layer of the hydraulically linked bearing layer of lean concrete is subsequently destroyed. Tests on the Test Loop of the train with an axial load of 23.5 tons showed that the BVSP design can be used for freight traffic. It is impractical to arrange ballastless track on one of the track of a two-track section. It is necessary to exclude the ingress of water between the bearing concrete slab and the hydraulically linked bearing layer (HLBL). The significant risks are that the ballastless track is more demanding for maintain the construction technology, the composition of the concrete mixes and the quality of the substrate preparation, as evidenced by splashes from the concrete bearing slabs. The probability of a malfunction on the ballastless track is much smaller, but the risk of a sharp increase in the costs of its elimination is much higher. Tests made it possible to confirm the working capacity of the ballastless railway track for the conditions of the Russian railways, to reveal the features of the current maintenance of each design and to give recommendations on its improvement. The tests carried out at JSC “VNIIZhT” test site showed that the ballastless track can be used not only for express and high-speed traffic, but also for combined and freight traffic.

The article presents the structure and the main characteristics of systems of a multi-purpose thermal high-precision testing bench for firing tests of non-hypergolic low-thrust rocket engines (LTRE). The vacuum system provides the initial vacuum in the chamber; the fuel system makes it possible to conduct research and tests of LTRE with the thrust 5...500 N in continuous and pulse modes of operation. The thermal conditioning system creates and maintains the temperature of the fuel components in the range from -15 to +50C at the inlet of the engine. The thermostats ensure a minimum temperature of gaseous working fluids ~ 100...120 K during tests conducted according to special programs. An automatic system of control, acquisition, handling and displaying of the measurement information is intended to support research and testing of rocket engines and to obtain real-time results. The measuring system is equipped with high-precision sensors that significantly increase the accuracy of the LTRE parameters to be determined. An infrared thermal imaging system makes it possible to assess the thermal state of the engine. The results of experimental research of the work process of non-hypergolic rocket engines are presented. We also present information on the dynamic and energy parameters of promising schemes of LTRE using the components Н2г + О2г, and on the thermal condition of the engine structure.

Meliorative fleet replacement and expansion of lands areas of melioration systems during radical improvement of not used, degraded layland are the two interconnected directions. They can be provided during introduction of science based modern System of technologies and machines for the complex mechanization of meliorative works. This System is the most fully answering to a problem of import substitution of the food, carrying out monitoring of the market of digging and special meliorative equipment. The authors presented the review of realization of System of machinery during the period since 1955 so far. Machines test play a part in regulation of the meliorative equipment market. Improvement of basic technologies of performance of maintenance activities on melioration systems, along with addition with new operations, is possible by creation of the multipurpose combined machines with working tools which novelty is confirmed with patents. The authors proved the project of part of System of machinery for maintenance activities on melioration systems for the period 2015-2020.

One of the promising ways to boost the gas turbine engine is to install a pulse detonation module in the exhaust case. Research on the effectiveness of the developed module in the expenditure thermal vacuum chamber, providing a complete simulation of these terms and conditions, requires unique equipment, as well as the significant financial and oper- ating costs. Accordingly ,it is more efficient to conduct performance and effectiveness assessment of the pulse detonation module using the existing test rigs, modified to partially simulate flight conditions comprising: a platform with the studied gas turbine engine (GTE), a power plant on a movable platform, pressurization system pipeline from an auxiliary power unit (APU) to the test engine, fuel and electrical systems of the test rig. The article presents small-size GTE pressurization system design results. The pipeline design is based on the conditions of mutual arrangement of the studied GTE and APU test cell. The choice of design solutions for production and assembly of components of the pressurization system, and the results are presented algorithm and calculating geometrical parameters ejector providing the required pressure and air flow temperature at the inlet to the studied engine. As a result, the research reasonably determined the structural diagram of the boost system test rig, providing a partial simulation of flight conditions at the inlet to the small-sized turbine engine. There were defined the necessary geometry and gas-dynamic properties of the gas ejector, the use of which as part of test rig pres- surization system will start the series of studies, according to the pulse detonation performance of the module.

The problem of the scope of ballastless track superstructure (BTS) and its service life currently is urgent. Due to the high traffic density at the Test Loop of JSC "VNIIZhT" for a short period of time it is possible to get an idea of BTS service life with freight transport at a speed of 80 km/h and axle load of 23.5 tonnes per axle. For information on BTS service life in real conditions of high-speed up to 400 km/h and axle load to 18 tonnes it would takes several decades.To resolve this contradiction it is proposed to apply a new methodology for forecasting the estimated service life of BTS at actual high-speed traffic by the results of tests on Test Loop with using mathematical modeling.In the proposed model track vibrations are considered as vibrations of construction comprising of three endlessly long beams, the bottom of which is based on a modified Winkler base and the upper and middle rely on the elastic layer mainly having a base characteristics as Winkler base. For specific design of ballastless track it would be the rail, the concrete support plate (track concrete) and hydraulically bound layer (lean concrete) correspondingly.The calculation results are presented in the form of amplitude-frequency characteristics of the bending moments in the second layer of ballastless track structure. Given the fact that the amplitude-frequency characteristic is not dependent on the axial load, the calculations are made for the particular case when the values of the speed of 80 km/h and 300 km/h with the actual characteristics of the layers of ballastless track that is operated on the Test Loop of JSC "VNIIZhT".The proposed algorithm and methodology make it possible to transfer the results of observations of the processes of degradation of tested ballastless track design, obtained at the Test Loop (st. Scherbinka), on sections of network, where installation of track of this design for mixed transport is assumed. In the future, this technique allows taking into account changes in the area of operational factors, including the effect of increasing the axial load or speed of trains on the durability of track design.

Football is one of the most popular sports in the world. One might venture to say that this is a competition bringing together the largest number of trainees of people, both those affiliated sports clubs and amateur playing football with traffic needs and for pure pleasure. High requirements before players are forcing bars training to effectively conduct the training in order to meet them. Checking in sport is one of the indispensable elements of proper training, which allows both to dispense the appropriate load as well as to monitor progress in the training process which, together with an individual approach to player creates optimal conditions for its development. In the study presented and discussed stress tests which are elements of control in sport. They discussed included attempts to run at a maximum speed of 30m with the measurement of split times on 5m and 10m, anaerobic power test RAST - Running- based Anaerobic Sprint Test, vertical jump on the platform dynamometer - Countermovementjump - CMJ, agility test - 20 Yard Agility Shuttle. The tests were carried out twice at an interval of four months. Obtained in the process of the research results were processed statistically, discussed and presented in the form of tables and graphs. The entire activities related to the research process enabled the formulation of the summary, which merits is that over time of 27.01.2014r. to 23.01.2014r. there was an average increase physical fitness of the total surveyed players. It was also observed that the greatest changes occurred in the trials RAST and CMJ. There has been no significant improvement in the speed of locomotion and agility. Training loads during the preparatory period and the start of the group surveyed players proved to be particularly effective in improving anaerobic capacity and explosive strength respondents. Based on the results that have been obtained in all the tests you will notice big differences in terms of overall physical fitness among the respondents.

The article discusses the level of physical preparedness of students. Physical fitness was determined by the method of testing. The study involved 240 youths in the economic University, living in different regions of Crimea. It is revealed that the introduction of innovative pedagogical educational technologies improve the physical training of students.

Prototype of the machine for extraction and scarification of clover seeds КС-0.2 was tested. The machine is used for extraction of seeds from the wad of clover and scarification of hard grass seed. The purpose of the test -determination of agro-technical, operational-technological, economic performance of machines; safety indicators, ergonomics and reliability of the machine. Verification of its conformity to requirements of the technical specifications (TS) and normative documentation (ND). Wad of clover Kirovskij-159 was used for extraction of seeds. Seeds of Galega orientalis were used for scarification of seeds according to requirements of State standard 52323-2005. The test results revealed that the machine is functioning and efficiently performs processes of extraction of seeds from the wad of clover and scarification of hard grass seed. The machine complies with the basic requirements by assignment, reliability, security, and parameters of operation and technologies. The machine provides degree of seeds extraction 97.5.94.4 %, crushing of seeds 0.82.0.31% with productivity 0.16.0.38 t/h; degree of scarification of seeds 98.7.99.1%, crushing of seeds 1.2...1.6 % with productivity 0.19.0.33 t/h. Machine fits into the technology of seed production of perennial grasses and is recommended for use in agricultural production.

Experimental and theoretical methods of studying life characteristics of metal-composite high-pressure cylinders are considered. It is shown that the stiffness of a load-bearing composite shell has a considerable effect on service life of the cylinders. Experimental results and their comparison with data of theoretical calculations are presented.

This article considers the problem of assessment of data authenticity related to reliability of the flight data obtained in processing the information of portable GPS receivers’ during air accident investigations, which are characterized by the lack of standard flight data recording systems. Appropriate recommendations the improvement improving of the newly developed GPS receivers have been developed and implemented.

The large base of support of catenary supports on railways sets urgent task to assess their condition and load capacity. Condition of catenary supports evaluated during operation. In addition to the existing supports on the railways there are new types, such as supports, manufactured using composite materials. To confirm their reliability and performance in terms of rail transport it is necessary to carry out complex tests. Tests are offered to perform in two stages: 1) bench tests to check mechanical properties and geometrical indicators; 2) accelerated life cycle testing. Accelerated life cycle tests are divided into bench and operational. For the bench accelerated tests a stand for vibration loading of racks of catenary supports is designed, which allows carrying out tests to determine resistance of supports to vertical vibration, resistance to relative creeping of racks. The stand has the ability to create static loading for racks of catenary supports up to 40 kN and dynamic loading up to 10 kN at a frequency of applying loads up to 5 Hz. Description and the scheme of the stand of vibration loading for racks of catenary supports are provided in article. Parameters of vibration loading are chosen. The technique of carrying out accelerated life cycle tests is offered. The technique of vibration loading is given. Bench tests of racks for catenary supports by the offered technique allow giving an assessment to a possibility of application of new types of supports in the conditions of railway operation.