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Copyright of Health Sport Rehabilitation is the property of H.S. Skovoroda Kharkiv National Pedagogical University 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.)

Copyright of Health Sport Rehabilitation is the property of H.S. Skovoroda Kharkiv National Pedagogical University 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.)

Introduction. Efficient operation of a system for measuring rail surface short-wavelength irregularities depends on evaluation of the signal length with respect to travelled distances, i.e., the standard maximum defect length and the distance between the wheels of a car bogie. When recording an accelerometer signal with respect to time due to the effect of velocity, the signal length corresponding to these spatially constant distances will vary.Aim. Development of an algorithm for determining rail running surface defects using the data obtained by accelerometers mounted on the axle boxes of a car bogie under their not equidistant spatial record.Materials and methods. The data obtained when passing a laboratory car equipped with a system for measuring short-wavelength irregularities was used. The search and determination of irregularity parameters was carried out by an inertial method. The methods of normalization and correlation analysis were used.Results. An algorithm for determining rail running surface defects based on an inertial method was developed, considering the spatial non-equidistance of the signal. The implemented correlation analysis allows compensation of high-velocity errors when determining the defects. In the considered example, the relative error equaled 0.4 %. Compensation of velocity errors reduces the probability of type I errors in defect determination.Conclusion. The developed algorithm considers velocity errors associated with the application of inertial methods for detecting short-wavelength irregularities. The implementation of correlation analysis reduces the probability of type I errors when determining rail running surface defects.

Objective. The purpose of the study is to determine the coordinates of the earthquake hypocenter with the simultaneous determination of the seismic wave velocity.Method. The study is based on the use of figures of the fourth and second order - the Cassini oval and hyperbola, figures of the second order - ellipse and hyperbola and combined methods that allow, at given seismic wave velocities, according to three seismic sensors, to determine the coordinates of the earthquake hypocenter. In this case, the velocities are assumed to be known a priori. According to the readings of the fourth seismic sensor, and for given seismic wave velocities, the distance from the fourth seismic sensor to the hypocenter is determined. Again, according to the coordinates of the fourth seismic sensor and the hypocenter coordinates calculated from the three seismic sensors, the distance between them is calculated. If the seismic wave velocities do not correspond to the true ones, a discrepancy will appear between the two calculated values of the distances from the hypocenter to the fourth seismic sensor. By varying the velocities of seismic waves when calculating the coordinates of the hypocenter, we achieve a minimum discrepancy.Result. The problem of determining the coordinates of the earthquake hypocenter with the simultaneous determination of seismic wave velocities is solved. The error distribution densities in determining the coordinates of the earthquake hypocenter and seismic wave velocities are obtained.Conclusion. The proposed method makes it possible to increase the accuracy of determining the coordinates of the earthquake source, as well as to refine the values of seismic wave velocities.

Numerical modeling methods have been used to study the effect of an emergency stop of the fuel mixture supply through individual burners on the aerodynamics of the flow in the combustion chamber of a power boiler. The performed computational experiments made it possible to obtain the main aerodynamic characteristics of heat and mass transfer processes (full velocity vector, pressure, kinetic energy of turbulence and dissipation energy) in the volume of the combustion chamber and at the exit from it in emergency mode (two swirl burners are operating) and compare them with traditional solid fuel combustion (basic mode - four direct-flow burners are working). The results obtained indicate that with a vortex fuel supply in the central region of the combustion chamber, a sharp change in aerodynamic characteristics is observed with the formation of a vortex flow, which weakens as the pulverized coal flow and combustion products move to the exit. The presence of a vortex flow causes stable combustion of solid fuel and uniform distribution of heat flows along the walls of the combustion chamber. In addition, the vortex nature of the flow increases the residence time of coal particles in the combustion chamber, which contributes to a more complete burnout and a decrease in the mechanical underburning of the fuel mixture. Such a detailed study of the aerodynamic flow pattern that takes place in the combustion chamber of power boilers of operating TPPs can only be obtained by numerical simulation methods and by performing computational experiments. The highly informative results obtained make it possible to develop "clean" energy production technologies and solve environmental problems of the emission of harmful substances into the environment. [ABSTRACT FROM AUTHOR]

Objective. The aim of the study is to develop methods for determining the coordinates of the hypocenter of an earthquake with a known structure of the earth's crust. Method. To solve the problem, the brute force method, the confidence interval, the comparative method and the enumeration of possible options on the grid are used. Result. A method has been developed for determining the coordinates of an earthquake source with a known structure of the earth's crust using points of various figures of the n-th order as geometric locations in calculations. Conclusion. The proposed method, with the known structure of the earth's crust, makes it possible to use all known methods that require information on the travel time differences of seismic waves to spaced seismic sensors and the difference in travel times of longitudinal and transverse seismic waves to the seismic sensor for calculating the coordinates of the earthquake hypocenter. The accuracy of determining the coordinates of the earthquake hypocenter depends on the quality of determining the structure of the earth's crust on which the seismic event was observed.

Objective. The aim of the study is to develop a method for determining the coordinates of the earthquake hypocenter using various combinations of second and fourth order figures as a geo-locus of the hypocenter position points.Method. It is known that the line of intersection of figures of the second and fourth orders, in the case of coincidence of focuses, is a circle. To determine the coordinates of the earthquake source, data from seismographs are used, which are used to construct figures of the second and fourth order, the intersection point of which is the hypocenter. When using data from two seismic sensors, there are two figures, the intersection line of which is a circle. A sphere with a radius equal to the radius of the circle is constructed through the center of this circle. For the other two pairs of seismic sensors, two more spheres are also formed, The intersection point of the three spheres obtained is the sought-for hypocenter of the earthquake.Result. A method has been developed for determining the coordinates of an earthquake source using different shapes of the second and fourth orders for different pairs of seismic sensors.Conclusion. The method allows one to select one of the second or fourth order figures for different pairs of seismic sensors, which makes it possible to reduce the error in determining the source coordinates.

Introduction. Driving at a speed exceeding the permitted and average speed of traffic flow often leads to a collision of vehicles with other road users or with elements of the arrangement of highways. As a result, it is necessary to establish whether the fact of this violation of the traffic rules, which led to the occurrence of an emergency-dangerous road traffic situation. The methods used to calculate the speed of vehicles based on the resulting deformations are quite accurate, but this fact is true in conditions of complete overlap (impact across the entire width of the front, rear or side parts of the body). But there is a scientific task of developing a methodology according to which an expert or investigator will be able to calculate the average statistical value of measuring the depth of deformation of a vehicle for a specific road traffic situation.Materials and methods. The paper proposes a method for evaluating the possibility of using the data available to the expert for calculation by introducing the coefficient of variation of the depth of penetration. With the help of the coefficient of variation, the specialist has a tool for selecting and ignoring individual measurements of the depth of penetration, depending on the degree of overlap and on the ‘spread’ of the deformation values.Conclusions. After studying a number of collisions with incomplete overlap and excluding the ‘extra’ values of penetration, the speed equivalent to the energy cost for the development of residual deformations and errors (the difference between the true collision speed and the established one without taking into account the ‘falling out’ values of deformations) was calculated and it was found that the use of the algorithm taking into account the coefficient of variation led to sufficiently accurate calculation results.Discussions. The proposed methodology regulates the use of the coefficient of variation as a criterion for the admissibility of the use of source data to determine the quality of the final result of the calculation. This mathematical device is applicable to all collisions, but is especially relevant when studying collisions with incomplete overlap of any part of the car body.

Objective. The study is aimed at determining the dependence of the average error in calculating the epicenter coordinates of an earthquake on errors in measuring the velocities of seismic waves for various methods of seismic event localization. Error distribution investigation for the method for determining the earthquake hypocenter coordinates using the Cassinian oval. Methods. The problem was solved using statistical methods: methods of frequency and regression analyzes, means comparison method, and uniform search method. Results. A relationship between the accuracy of measuring the velocities of seismic waves when determining the coordinates of an earthquake epicenter were established for four different earthquake hypocenter coordinates calculation methods. A method for determining the earthquake hypocenter coordinates using the fourth-order figure of the Cassinian oval was proposed. The error distribution density of the Cassinian oval method was compared with the ones of other methods. Conclusion. The results obtained make it possible to choose one or another method for calculating the hypocenter coordinates depending on the specific area in which a seismic event occurred and the locations of seismic sensors.

Objective. The objective of the study is to determine the requirements for various devices of hydraulic reclamation machines, which are widely used in the construction of canals and drains, to maintain a given slope, as well as the calculation of the executive mechanism that serves to eliminate the oscillating movement of the working body relative to the line of the specified slope.Methods. A mathematical description of the vibrations of the working body for caterpillar hydraulic reclamation machines with mounted working bodies is given.Results. The article presents the results of research to identify the main factors affecting the oscillations of the working body of caterpillar reclamation machines. As a result of theoretical and experimental studies, it was found that when a caterpillar machine with a rigid undercarriage crosses single and multiple irregularities, the movement of the cutting edge of the rigidly mounted working body is graphically depicted by sinusoidal curves. The obtained dependencies allow conducting calculations of the automatic system of maintaining the specified slope and establish the area of stable modes of system operation. A geometric method for optimizing the hinge linkage of the working body of trenchless pipelayer is presented.Conclusion. The proposed methods of improving the performance of caterpillar hydraulic reclamation machines with mounted working bodies when moving on uneven ground surfaces can be used to create a wide class of mounted earthmoving machines, both with passive and active working bodies.

Introduction. The article presents the results of an experimental study of the individual temporal characteristics of cognitive space management in students while solving problems. Methods. The methodological tools are briefly described, including traditional test questionnaires for identifying temporal features of subjective perception of time (‘Semantic Time Differential’, ‘Time Perspective’), as well as modified and original research methods for identifying temporal characteristics of the cognitive activity of subjects in solving spatial problems in a laboratory experiment (‘Mental rotation’, ‘Accuracy’). Results. In a series of laboratory experiments, new research data were obtained on the temporal specificity of the process of constructing a personal cognitive space in students. Using prognostic modeling procedures, we were able to record the presence of structural relationships between the time perception, cognitive characteristics of problem-solving, and stability of academic performance. It was experimentally proved that characteristics of time reaction and effectiveness in completing accuracy tasks and mental rotation tasks act as temporal predictors of levels of students’ academic performance. Discussion. The study revealed the fact that students with a dominant temporal orientation toward the present situation, looking constantly for new stimuli and feelings in the current time, had quite pronounced deficits in the choice of educational strategies based on more long-term and well-defined objective in the future. It was noted, as an important aspect in the personalization of studying, that students must be aware of their own temporal, cognitive and other characteristics of the information processing, and manage on their own their educational environments as appropriate. The possibilities are discussed in using cognitive diagnostic characteristics to predict and timely correct individual trajectories of students’ educational paths as part of the adaptive approach to education.

Introduction. Precision elements of the target equipment and sensitive elements of the stabilization and orientation system of the advanced spacecraft are considered in the framework of this research. A method and software for modeling the dynamic characteristics of these elements are developed and validated. At that, the processing data results from the experimental studies on active and passive oscillators are taken into account.Materials and Methods. It is shown how the method of weightlessness provides simulation of the conditions that as much as possible conform to the real-time use of advanced space vehicles, precision structural elements, target equipment and their drives. Schemes of the corresponding experimental facilities are presented. Mathematical modeling methods, techniques of machine mechanics and dynamics are applied. Basic parameters of the proposed design dynamics, which are governing parameters in terms of the implementation of the target functions of the spacecraft, are calculated. Rational versions of layout and approximate cycle patterns of the operation of advanced space vehicles are formed to reduce microperturbations from driving gear with rotating masses.Research Results. A simulation technique for the dynamic characteristics of the drives of advanced space vehicles considering the regular oscillator operation is developed and validated. A complex of methods is presented for solving the problems of identifying dynamic parameters of a mathematical model of an advanced spacecraft based on the processing data results obtained through the experimental testing of active and passive oscillators. Two types of vibration from flywheel engines are noted. The first type is according to the commands of the position control and stabilization control system. The second type is due to residual imbalance from the solar constant meter. It is shown how these vibrations affect the dynamic characteristics of the gyro mounting seats and of the multispectral scanner for hydrometeorological support of the spacecraft. The data obtained are meant to solve the problems of assurance of the dynamic accuracy of advanced space vehicles.Discussion and Conclusions. A technique for modeling the dynamic characteristics of advanced space vehicles when operating in the precision orientation mode is proposed. The solution is based on the results of theoretical and experimental studies presented in the paper, and it considers the operation of standard oscillators. The implementation of this method is brought to software and algorithmic support for assessing the dynamic characteristics of standard oscillators of an advanced space vehicle. Recommendations to reduce the effect of active oscillators are established. Initial data are selected to determine the dynamics of advanced space vehicles from the point of view of fulfilling their target functions. The layout and approximate cycle patterns of the operation of advanced space vehicles to identify the driving gear with rotating masses as sources of micro-perturbations are proposed.

The paper presents a fragment of on-going investigations directed on creation of optimum data environment that ensures an access to world scientific journals and other publications which are necessary for qualitative implementation of works on priority directions of R&D in the field of road-construction industry in the period of 2016–2020. A citation analysis has been applied while using data of Journal Citation Reports for selection of world scientific serial publiccations which are necessary for execution of investigations on heat and mass transfer in road dressings. The road dressings are considered as open heterogeneous thermodynamic systems. Their deformations occur under various climatic conditions due to heat and mass transfer processes and interaction of transport flows and road surface. Crack formation takes place in depth of the road dressings and on road surfaces as a result of temperature, mass transfer processes. As it is known material structure of constructive layers especially which are created with the help of technogenic wastes (asphalt-concrete, concrete, reinforced concrete scrap and products of its recycling, brick rubble, various wastes of production etc.) influence on heat and mass transfer. The paper presents results of investigations on heat flows, boundary layers according to air viscosity, velocity of geometric permeability characteristics, capillary pressures in road pavements.

One of the most important aspects in terms of increasing the efficiency of agricultural production is the improvement of the methods and tools of determining the main operating indicators of tractors as they influence the productivity, efficiency and ecological safety of machine­tractor units. (Research purpose) To develop a method for obtaining traction characteristics of a tractor, which make it possible to reduce the time needed for measurements under operating conditions, and to design an instrument for economical obtaining of tractors’ traction characteristics under specific farm conditions. (Materials and methods) the authors have chosen a method for determining the energy performance of tractors under operating conditions in a transient mode. They have conducted traction tests of tractors for various modes and soil backgrounds to evaluate its traction­dynamic and fuel­economic indicators. The traction characteristic of a tractor is the dependence of the tractor performance (traction power, speed, hourly and specific fuel consumption, and slipping) on the load at various speeds against a given soil background. However, traction tests require expensive equipment, as well as significant costs and time to prepare and conduct, which leads to their implementation only in the conditions of machine testing stations. (Results and discussion) The authors have developed a method for obtaining traction characteristics of a tractor under operating conditions. Instantly increasing the fuel supply to the maximum, during the tractor acceleration, the engine crankshaft speed and track­measuring wheel were measured at a given speed and against the corresponding soil background ­ with load and without load. It has been revealed that the fuel and economic indicators can be determined using cyclical fuel supply by the fuel pump at the maximum mode on the bench for checking and adjusting the fuel equipment. The authors have developed and assembled a measuring and computing installation that allows processing arrays of data from two inductive sensors. (Conclusions) The proposed method for determining the traction­dynamic and fuel­economic indicators of tractors and the measuring­computing installation that implements it allow obtaining a traction characteristic (speed, slipping, traction power, hourly and specific fuel consumption depending on the load at various speeds against a given soil background) in operating conditions, thus reducing the time and cost of operation.

Актуальность работы. Задание сейсмических воздействий в отечественных строительных нормах практически не меняется в течение последних 60 лет. Накопленные эмпирические данные по сильным движениям позволяют коренным образом усовершенствовать методику расчета зданий и сооружений на сейсмостойкость. Ожидается снижение погрешностей расчета примерно вдвое. Цель работы. В последнее время много внимания уделяется проблемам построения карт сейсмической опасности в ускорениях. Однако по традиции в нашей стране такие карты оценивают сейсмическую опасность в баллах шкалы сейсмической интенсивности. В большинстве стран сейсмическая опасность оценивается именно в ускорениях. Строились такие карты и в нашей стране. В частности, карты ОСР-97 и ОСР-2012 имели вариант и в ускорениях. Построение карт сейсмической опасности в ускорениях не имеет принципиальных трудностей. Проблема в том, что ускорения не являются адекватной мерой сейсмических воздействий. Более половины века тому назад американские ученые на эмпирическом материале показали, что связь ускорений с баллами, а, следовательно, и с повреждаемостью зданий неоднозначна: шкалы сейсмической интенсивности различны для разных расстояний и грунтов. Ошибка в оценке последствий землетрясения по ускорениям грунта может достигать 2 баллов. Следовательно, расчет ожидаемых воздействий следует производить с учетом других характеристик сейсмических волн. К тому же, попытки построения карт сейсмической опасности строились без учета данных инженерной сейсмологии и с нарушениями правил теории вероятностей и поэтому обладают не только определенными достоинствами, но и серьезными недостатками. Некоторые исследователи считают, что скорости колебаний лучше коррелируются с повреждениями сооружений, по крайней мере, многоэтажных зданий и подземных трубопроводов. Методы работы. Однако анализ эмпирических данных показал, что использование ускорений, скоростей и смещений характеризуется примерно одинаковой точностью. Рассмотрены способы построения карт общего сейсмического районирования. В действующей шкале сейсмической интенсивности ГОСТ Р 57546.2017 приведены оценки корреляции повреждаемости зданий с различными параметрами сейсмических колебаний: ускорениями, скоростями, смещениями, мощностью колебаний грунта. Оценено влияние продолжительности колебаний. Результаты работы. Показано, что дальнейшее повышение надежности расчетов объектов на сейсмостойкость связана с представлением сейсмических воздействий не с амплитудами колебаний, а с энергетическими характеристиками сейсмических волн.

Copyright of Scientific Bulletin of National Mining University is the property of National Mining University, State Higher Educational Institution 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.)

For successful powder deposition and a good quality of deposited layers, the following factors are of great importance: uniform powder injection into the plasma jet, transfer of heat and velocity of plasma particles (ions and electrons) to powder particles as well as the temperature and speed of molten powder particles before the collision with the substrate. For each powder type, depending on the distribution of particle granulation (μm) and density (kg/m3), it is necessary to determine the amount of powder supply (g/min) in the plasma for defined gas flows (l/min), types of plasma gases (Ar, He, H2, N2 or their mixtures) and power supply levels (kW). For the transfer of heat and speed of plasma particles to powder particles, there must be an interaction between the ions and electrons from the plasma and the powder particles. For already known plasma jet speed and temperature values at atmospheric pressure, trajectories of individual particles can be calculated using the equations of motion taking into account viscous friction and inertia. The paper describes the relation between the speed of Al2O3 powder injection and the velocity of individual Al2O3 powder particles in the plasma depending on the distance from the anode opening, as well as the relation between powder granulation and the temperature of the surface of powder particles depending on powder injection and the level of plasma gun power supply at atmospheric pressure. / Для успешного и качественного нанесения порошкового покрытия, очень важны следующие действия: равномерное впрыскивание порошка в струю плазмы, передача температуры и скорости частиц плазмы (ионов и электронов) частицам порошка и температура и скорость расплавленных частиц порошка до соприкосновения с основанием. По каждому виду порошка в зависимости от распределения грануляции частиц (μm) и плотности (кг/м3) необходимо определить количество порошка (г/мин) в плазме для определения потока газов (л/мин), видов плазменных газов (Ar, He, H2, N2 или их смеси) и уровня мощности (кВт). Для того чтобы осуществилась передача тепла и скорости частиц плазмы на частицы порошка должно произойти взаимодействие между ионами и электронами плазмы и частицами порошка. В случае, если известны скорость и температура плазменной струи при атмосферном давлении, то можно рассчитать траекторию отдельных частиц с помощью уравнений движения, учитывая вискозное трение и инерцию. В данной работе представлены скорость напыления порошка Al2O3 и скорость отдельных частиц порошка Al2O3 в плазме, в зависимости от расстояния от анодного отверстия, а также связи грануляции порошка и температуры поверхности частиц порошка, в зависимости от впрыска порошка и уровня мощности плазменного распылителя при атмосферном давлении. / Za uspešno deponovanje praha i dobar kvalitet deponovanih slojeva od velikog značaja je ravnomerno injektiranje praha u mlaz plazme, prenos toplote i brzine čestica plazme (jona i elektrona) na čestice praha, kao i temperatura i brzina istopljenih čestica praha pre sudara sa podlogom. Za svaki tip praha, u zavisnosti od raspodele granulacije čestica (µm) i gustine (kg/m3), neophodno je odrediti količinu dotura praha (g/min) u plazmi za definisane protoke gasova (l/min), tipove plazma gasova (Ar, He, H2, N2 ili njihove mešavine) i nivoe snage (kW). Da bi došlo do prenosa toplote i brzine čestica plazme na čestice praha, mora doći do interakcije između jona i elektrona iz plazme i čestica praha. Za poznate brzine i temperature mlaza plazme na atmosferskom pritisku mogu se izračunati putanje pojedinih čestica primenom jednačine kretanja, uzimajući u obzir viskozno trenje i inerciju. U radu je prikazana veza između brzine injektiranja praha Al2O3 i brzine pojedinih čestica praha Al2O3 u plazmi u zavisnosti od odstojanja otvora anode, kao i veza granulacije praha i temperature površine čestica praha u zavisnosti od injektiranja praha i nivoa snage napajanja plazma pištolja na atmosferskom pritisku.

Автокөлік, әр түрлі саладағы өндірістік кәсіпорындардың, өндірушіден тұтынушыға жүктерді тасымалдауды жүзеге асырып, логистика деп танылатын тауар қозғалысы жүйесінің құрамына кіреді. Кәсіпорындар логистикалық тәсілдерге және шаруашылық байланыстарға ере отырып, клиенттерге қызмет көрсету кезінде аз шығынмен өнімді жеткізу сапасын арттыруда бір бірімен бәсекелеседі.Көліктік кәсіпорындарға логистиканың тиімділігін арттыру, біріншіден, автомобильмен жүк тасымалдау нарығында бәсекелестік көп және екіншіден, көліктік шығындар логистиканың жалпы құнының 35 тен 50 пайызға дейін құрайтынымен анықталады. Сондықтан, автокөліктік кәсіпорындарға көлік шығындарын үнемдеу өте маңызды. Зерттеулер мен публикацияларды талдау барысында, тиімділік көрсеткіштерін таңдау мәселесімен көптеген ізденушілердің айналысқандары анықталды. Автомобиль көлігінің логистикалық қызметін бағалау бағытында көптеген шетелдік және отандық ізденушілердің зерттеулері логистикалық тәсілдерді пайдаланып автокөлік кәсіпорындарының тиімділігін арттырудың маңыздылығы мен өзектілігін көрсетті. Мақаланың мақсаты - автомобильмен жүк тасымалдаудың тиімділігін бағалау көрсеткіштерін талдау және тасымалдау өзіндік құнына жылдамдықтың әсер ету деңгейін анықтау. Мақсатқа жету үшін, автомобиль көлігімен тасымалдаудың тиімділігін бағалау мәселесіне арналған ғалымдардың еңбектері талданды. Жылдамдықтың тасымалдау өзіндік құнына әсерін профессор Д. Тестің анықтаған алгоритмімен, MS Excel бағдарламасы көмегімен анықталды.

The processes of value changing of the restitution coefficient in a direct сentral impact of deformable bodies are presented, because values of the restitution coefficient are necessary for calculation the striker dynamics and the tool in the construction mechanisms and mining machines. The of kinetic energy loss of the colliding bodies after each impact is interrelated with the module of the restitution coefficient , which can vary for the same material from 0 to 1 at a different geometry of the interacting bodies .The analysis of the coefficient changes because of the recovery factor from the geometry of the colliding bodies is shown. At low impact velocities, when the bodies have the same shape and weight or when they hit the rob or the globe on a massive and hard obstacle, the recovery factor is approximately equal 1. When short rod hits to long and with the same diameters and the materials of the bodies, the restitution coefficient is equal the ratio of the lengths of the rods and it is also equal zero at impact of the rod on a thin plate. It is more rational to determine the restitution coefficient experimentally for bodies of complex shape. Experimental setup for determination of the recovery coefficient is observed, when it is theoretically difficult to calculate, especially at small impact velocities on horizontal and vertical stands or at medium and high speeds, or in Koper, operating on the principle of accumulation of energy for the shot. It is possible to vary not only the different geometry and materials of the colliding bodies, but also their convergence rate before contact.

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In this article the reducer design with variable transfer number is offered and proved. The reducer allows to make dispersal and the movement of the crane (cart) with three speeds with smooth gear shifting. Couplings are built in cogwheels. Design compact, simple and reliable. Decrease in dynamic loadings, rocking of freight is provided. As a prototype couplings accepted way clutch cylindrical roller. The proposed clutch gearbox comprise tapered rollers. Keywords: reducer, coupling, transfer, speed.

The computer simulation problem of the dynamics of elastic tube serpentines with internal flows of boiling liquid is set up. The clots motion model of the non-homogeneous boiling liquid is proposed. The numerical solution technique of the constructed equations based on the use of an algorithm for numerical integration in time and a method of the transfer matrix. [ABSTRACT FROM AUTHOR]

Copyright of Renewable Energy / Vidnovluvana Energetyka is the property of Institute of Renewable Energy of NAS of Ukraine 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.)

Researches for clarification of influence of temperature and speed of heated air on dynamics and duration of process of heating of compotes in SKO 1-82-3000 container are conducted. Researches are conducted at speeds of heated air from 1,2 m/s to 8,5m/s and temperatures 120-1500C.It is revealed that for SKO 1-82-3000 banks it is possible to consider as the optimum temperature of the heat carrier (heated air) tv =150 and higher than 0C. The analysis of experimental data and their processing with use of a method of the smallest squares allowed to receive the equation for calculation of duration of heating of compotes in a stream of heated air in SKO 1-82-3000 container depending on temperature of the heating tv environment and its speed υв .The relative error by comparison of settlement and skilled data fluctuates within 5–8%

Thermal processing zone status when threading in heatproof, high-strength and titanium alloys is a major problem in the general theory of metal cutting. Under other equal conditions temperature in the processing zone of these materials is higher than in cutting of carbon structural steels, as they have high strength and ductility, low thermal conductivity, that makes difficult the working conditions of the taps, increases the area of the tool contact with the workpiece, deteriorates lubrication and cooling of the cutting area because of the increased tendency of heatresistant materials for the curing. This causes an increase in the work and force of friction and as a consequence the rise of cutting temperature. Research of temperature state of the threaded coils formation zone with combined countersink tool-tap is one of the major challenges facing the authors of this work. When performing the work was used factorial experiment. The temperature in the cutting zone of the thread was determined by a built-in chromel-aluminum thermocouple with thermoelectrode cross-sectional area 0,23mm2 . Experiments were carried out using the apparatus of mathematical statistics. Studies have shown that the greatest impact on the temperature state of the cutting area has a tensile strength of the material. Effect of cutting speed in the studied variation range is relatively less noticeable. The explanation for this is a special scheme of cutting of combined countersink tap which allows significantly improve conditions in the cutting zone. The proposed design of the tap allows to reduce the temperature in the area of tapping for 20%.

The integrated studies identified factors influencing wear resistance of tapping and part of the combined tool, which has been studied and optimized its kinetics. The influence of tool wear on geometrical figures thead, performance, torque. The main factors influencing the performance of processing threads. As a result of the study, it was found that the main factors are the cutting speed (V) limit the temporary v resistance of the material to be processed and the reverse cone angle δ. In order to optimize these parameters a full-factorial experiment. On the basis of the received data was built a graphical model of the optimum, which allows you to define basic settings for processing (V, φ), depending on the ultimate strength of the material and shows the kind of stability and performance of the tool.

In all high-vacuum mechanical pumps, namely molecular and turbo-molecular there is a need in sealing of inputs of the movement. A dynamic seals type find a wide application in modern industry. Protective properties and optimization of the dynamic seals at the stage of design become a relevant topic to be researched.The aim of the work is to develop a mathematical model of gas flow in the face gap between two rotating disks. In building this model, the following assumptions are introduced: molecular gas flow, full exchange of momentum in collisions of molecules with disk surface, reflection of particles from the wall submits to the law of diffuse reflection, distribution of gas molecules according to the thermal motion speeds being described by Maxwell`s law. The calculation is based on the use of Monte Carlo method (method of test particle), which consists in the statistical modeling of processes. The article describes an algorithm to construct a mathematical model step by step. The trajectory of each molecule movement is traced from the moment of its moving in till its moving out of the system. The article defines both a probability for gas molecules to pass through the face gap of disk vacuum pump in forward and backward direction and a conductivity of the gap.A numerical experiment based on the developed program has been conducted with considering the movement of the required number of molecules to provide a sufficient accuracy of calculation. Gas flow in the face gap of disk vacuum pump is studied. As a result of the experiment it was found that geometrical parameters of the gap and speed of disk rotation have an impact on the conductivity. With raising speed of disk rotation the probability for particles to pass in forward direction increases, accordingly increasing the conductivity, and for particles to pass in backward direction it decreases thereby improving the vacuum properties of the pump. The work carries out a process adequacy test based on the equality of the conductivity of the forward and reverse passages with disks being stationary. The accuracy does not exceed a tolerance. Results and, accordingly, recommendations, given in the article, can be used in designing a flow passage of the disk vacuum pumps, for providing a movement in high-vacuum mechanical pumps, and in calculating the overflows in the flowing passages of a similar pump design.

In 2009 there were constructed and brought into pilot operation two sections of RHEDA 2000 ballastless track designed by RailOne (Germany) with the participation of JSC ‘‘Roszheldorproekt”, one of them on the Moskovskaya Railway (in the VNIIZhT’s Testing Center at the station of Scherbinka) and another - on Oktyabr’skaya Railway (on the open line between Sablino and Kolpino). Prior to and in the course of pilot operation the VNIIZhT experts conducted actual loading tests at both sections and routine observations of various ballastless track components’ behaviour under increasing passed tonnage conditions. There are presented the most significant test and observation results as well as test results based conclusions.

The article presents modeling for investigation of aerodynamic processes on area sections (including a group of complex constructional works for different regimes of drop and wind streams and temperature conditions) and in complex constructional works (for different regimes of heating and ventilation). There were developed different programs for innovation problems solution in the field of heat and mass exchange in three-dimensional space of pres- sures-speeds-temperatures of оbjects.The field of uses of pneumobasic objects: construction and roof of tennis courts, hockey pitches, swimming pools , and also exhibitions’ buildings, circus buildings, cafes, aqua parks, studios, mobile objects of medical purposes, hangars, garages, construction sites, service sta- tions and etc. Advantages of such objects are the possibility and simplicity of multiple instal- lation and demolition works. Their large-scale implementation is determined by temperature- moisture conditions under the shells.Analytical and calculating researches, real researches of thermodynamic parameters of heat and mass exchange, multifactorial processes of air in pneumobasic objects, their shells in a wide range of climatic parameters of air (January – December) in the Republic of Belarus, in many geographical latitudes of many countries have shown that the limit of the possibility of optimizing wind loads, heat flow, acoustic effects is infinite (sports, residential, industrial, warehouse, the military-technical units (tanks, airplanes, etc.)). In modeling of convective flows in pneumobasic objects (part 1) there are processes with higher dynamic parameters of the air flow for the characteristic pneumobasic object, carried out the calculation of the velocity field, temperature, pressure at the speed of access of air through the inflow holes up to 5 m/sec at the moments of times (20, 100, 200, 400 sec). The calculation was performed using the developed mathematical model of convection processes, heat and mass exchange in unlimited space based on the laws of momentum conservation, continuity, thermal conduc- tivity and the boundary conditions for pneumobasic objects which allow analyze, calculate thermal, convection streams in three-dimensional space (part 1 (2014,No4)).

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For successful powder deposition and a good quality of deposited layers, the following factors are of great importance: uniform powder injection into the plasma jet, transfer of heat and velocity of plasma particles (ions and electrons) to powder particles as well as the temperature and speed of molten powder particles before the collision with the substrate. For each powder type, depending on the distribution of particle granulation (μm) and density (kg/m3), it is necessary to determine the amount of powder supply (g/min) in the plasma for defined gas flows (l/min), types of plasma gases (Ar, He, H2, N2 or their mixtures) and power supply levels (kW). For the transfer of heat and speed of plasma particles to powder particles, there must be an interaction between the ions and electrons from the plasma and the powder particles. For already known plasma jet speed and temperature values at atmospheric pressure, trajectories of individual particles can be calculated using the equations of motion taking into account viscous friction and inertia. The paper describes the relation between the speed of Al2O3 powder injection and the velocity of individual Al2O3 powder particles in the plasma depending on the distance from the anode opening, as well as the relation between powder granulation and the temperature of the surface of powder particles depending on powder injection and the level of plasma gun power supply at atmospheric pressure. [ABSTRACT FROM AUTHOR]

The paper reveals the creative perception of flight and speed at the beginning of a new era in the history of humanity – the era of aviation – as reflected in the works by Russian and French modernists, the most remarkable of whom is V. Brusov, in his poetry and drama, and M. Proust, in his epic «In Search of Lost Time». [ABSTRACT FROM AUTHOR]

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