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Results in Journal Technology transfer: fundamental principles and innovative technical solutions: 74

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Ivan Kulbovskyi, Halyna Holub
Technology transfer: fundamental principles and innovative technical solutions, Volume 2, pp 12-14; doi:10.21303/2585-6847.2018.00781

Abstract:
The analysis of the current state of power electric equipment of traction substations of railways, power supply systems for traction and control systems based on what was shown that current trends to ensure a high level of efficiency of the power industry are directly related to its informatization and the development of distributed computer systems and networks intellectual technology for monitoring, identifying and intellectualizing the management of energy saving modes of electric supply systems. The temporary decomposition of the tasks of management of electric networks of railways and the methodology of the organization of intelligent electric power traction networks are proposed. The methods for registering primary information monitoring parameters of normal and emergency modes of electric networks based on the use of mathematical tools of differential transformations and the presentation of data in the form of T-spectra are developed. On the basis of the system-wide principle of a single information space and the results of experimental studies, the architecture of the computer environment is studied, which reflects the range of possibilities for intellectualizing the traction network based on the characteristics of electricity supply to railways, taking into account restrictions and specificity of consumption. And at its base, modern computer-intelligent technologies have been created for managing energy saving in the process of power supply to railways at the level of traction substations, power supply distances and the upper level of the railway as a whole. The possibilities of the proposed structure of the intellectual traction electric network of Ukrzaliznytsia developed as a result of the mutual integration of the topology of the traction network of power supply and architecture of the computer environment, which is the infrastructure for managing power supply for railway transport, as well as the possibility of integrating real-time monitoring, state, optimization of consumption and management of energy saving in the process during the maintenance of electricity for traction at all levels of management of the railway in market conditions
Mykhailo Solomko
Technology transfer: fundamental principles and innovative technical solutions, Volume 2, pp 18-25; doi:10.21303/2585-6847.2018.00755

Abstract:
The object of research is the method of figurative transformations for Boolean functions minimization. One of the most problematic places to minimize Boolean functions is the complexity of the minimization algorithm and the guarantee of obtaining a minimal function. During the study, the method of equivalent figurative transformations was used, which is based on the laws and axioms of the algebra of logic; minimization protocols for Boolean functions that are used when the truth table of a given function has a complete binary combinatorial system with repetition or an incomplete binary combinatorial system with repetition. A reduction in the complexity of the minimization process for Boolean functions is obtained, new criteria for finding minimal functions are established. This is due to the fact that the proposed method of Boolean functions minimization has a number of peculiarities of solving the problem of finding minimal logical functions, in particular: – mathematical apparatus of the block diagram with repetition makes it possible to obtain more information about the orthogonality, adjacency, uniqueness of the truth table blocks; – equivalent figurative transformations due to the greater information capacity are capable of replacing verbal procedures of algebraic transformations; – result of minimization is estimated based on the sign of the minimum function; – minimum DNF or CNF functions are obtained regardless of the given normal form of the logical function, which means that it is necessary to minimize the given function for two normal forms — DNF and CNF using the full truth table; This ensures that it is possible to obtain an optimal reduction in the number of variables of a given function without losing its functionality. The effectiveness of the use of equivalent figurative transformations for Boolean functions minimization is demonstrated by examples of minimization of functions borrowed from other methods for the purpose of comparison. Compared with similar well-known methods of Boolean functions minimization, this provides: – less complexity of the minimization procedure for Boolean functions; – guaranteed Boolean functions minimization; – self-sufficiency of the specified method of Boolean functions minimization due to the introduction of features of the minimal function and minimization of two normal forms – DNF and CNF on the complete truth table of a given Boolean function
Andrii Bukaros, Vitalii Malyshev, Valeriia Bukaros
Technology transfer: fundamental principles and innovative technical solutions, Volume 2, pp 40-42; doi:10.21303/2585-6847.2018.00796

Abstract:
The basic requirements for control systems of automated electric drives of hermetic compressors of small refrigeration units are determined. The analysis of the existing sensorless control systems of three-phase AC drives is carried out. The topology of the adaptive Luenberger observer is proposed, which allows real-time evaluation of the current value of the rotational speed and torque on the shaft of the hermetic compressor motor. Based on the linearized model of a three-phase asynchronous motor, the Luenberger observer is synthesized by the modal method with the distribution of the roots of the characteristic polynomial in the standard linear Bessel form. Expressions are obtained for calculating the coefficients of the Luenberger matrix and the geometric mean root of the characteristic polynomial of the observer. To ensure the necessary accuracy of identifying the coordinates of the state of an automated electric drive of a hermetic compressor, an observer structure is proposed based on a complete mathematical model of a three-phase asynchronous motor made in a fixed coordinate system. Using simulation tools, the work of the designed Luenberger observer is studied on the example of a modernized three-phase asynchronous motor of a hermetic compressor of a domestic refrigerator. For this example, the coefficients of the Luenberger matrix and the geometric mean root of the characteristic polynomial of the observer are calculated. The effectiveness of the proposed method for identifying the rotational speed and moment of resistance of a compressor electric motor by an adaptive observer based on the calculation of the electromagnetic torque of the motor from measured sensors of phase voltages and currents is confirmed. The error of the observer under investigation does not exceed 0.5 % in rotation frequency and 10 % in respect to the moment of resistance. The resulting structure of the adaptive Luenberger observer allows to build closed-loop control systems for automated electric drives of the hermetic compressor of a small refrigeration unit.
Technology transfer: fundamental principles and innovative technical solutions, Volume 2, pp 49-51; doi:10.21303/2585-6847.2018.00767

Abstract:
A mathematical model of the distribution of mixture components in the equilibrium condensation telomerization is developed depending on the ratio of the amounts of monomers and telogen, as well as the number of HX as regulating parameters, the computer implementation of the model is carried out, and its study is carried out by numerical simulation. The model is based on the well-known schematic diagram of the flow of the condensation telomerization process under the assumption of equal reactivity of the same functional groups (Flory principle). Based on the analysis of the flow pattern of the process, 6 structural elements are identified, reproducible at each stage associated with an increase in the degree of polymerization based on 4 basic components. It is proved that the equilibrium concentrations of these elements, depending on the polymerization degree, depend on the equilibrium concentration of products with a degree of polymerization 1 and are described by infinite geometric progression with the same denominator. According to the physical content of the task, this progression must be convergent. Equations of material balance of components are contained in the form of a system with 4 equations containing infinite sums. It is possible to minimize these sums using the properties of geometric progressions and to obtain a closed system with 4 nonlinear equations for the equilibrium concentrations of the base components. The Monte Carlo method is used to study the features of the numerical solution of the system of equations of the model. It is found that with a random choice of initial approximations of solutions from an admissible region, the system contains 4 roots, of which 2 contain positive and negative components and are false, and 2 have completely positive components. A valid criterion for finding a real root has a physical meaning based on the calculation of the denominator of a geometric progression. The possibilities of practical use of the model are discussed
Hanna Slobodianyk, Nataliia Dolynska
Technology transfer: fundamental principles and innovative technical solutions, Volume 2, pp 46-48; doi:10.21303/2585-6847.2018.00770

Abstract:
The development of ports requires the construction of more and more deep-sea berthing facilities or the reconstruction of existing ones for servicing modern large-capacity ships. Traditional design solutions for deep-water berths are labor-intensive and material-intensive. The article describes the design of a deep-water berth in the form of tongue-and-groove wall with buttresses. Buttresses can be rectangular, trapezoidal with the extension downwards and trapezoidal with the extension upwards. The use of buttresses in the construction reduces the lateral pressure of the soil, increases the rigidity of the structure, and also increases the stability of the structure as a whole. The rational distribution of materials along the length of the structure and the unification of the elements leads to cheaper construction and a fast pace of construction. This solution can be used both in the construction of new berthing facilities and in the reconstruction of existing ones. The development of the calculated justification of the stability of the tongue-and-groove wall with buttresses, which optimally reflects the specificity of the structure, is carried out. Buttresses are an additional factor affecting the stability of the tongue-and-groove wall. Then, the stability of the structure as a whole depends on the resistance forces of the soil, arising in the plane of contact with the front wall and the resistance forces of the soil within the width of the buttress and involved, due to friction forces, in the joint work of the adjacent soil volumes. In order to determine the holding forces of the buttresses, experimental laboratory studies were conducted. Analysis of the results of the experiments shows that the trapezoidal buttresses with extension downwards have the greatest holding power. As a result of the mathematical modeling, the displacements of the wall and bending moments are plotted depending on the height of the buttresses. Thus, the design of the mooring structure of the innovative type can be used to create an economically deep-water berth with increased bearing capacity, which will be able to perceive modern ships with a large deadweight
Oleksii Shestopalov, Nataliia Ponomarova
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 57-59; doi:10.21303/2585-6847.2017.00521

Abstract:
The object of research is the process of the slime cleaning of the coal preparation plant from suspended solids by flocculation. The process of flocculation is multifactorial and depends on the concentration of the solid phase in the slime, the dispersed composition, the salinity, the pH of the medium, the concentration and degree of dilution of the flocculant and many other factors that have not been adequately studied in the current literature. Based on previous studies, it was suggested that the flocculant was introduced into the slime in two portions in an amount of 40 % and 60 % of the total flow. The aim of research is an experimental check of the influence of methods of dispersing and introducing the first portion of the flocculant onto the efficiency of sedimentation of the slime on the real slime. For this, in the diluted slime with water in a ratio of 1:1, the first portion of the flocculant is introduced in two ways: after diluting the slime with water and into the water before mixing it with the slime. It is established that the preliminary dispersion of the flocculant in a large volume of water leads to a significant increase (above 80-85 %) in the sedimentation rate of the formed floccules, as well as their strength to mechanical action
Yulia Shatohina
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 9-11; doi:10.21303/2585-6847.2017.00479

Abstract:
There were conducted the researches to identify new correlation between traditional controlling process indicators of cleaning stock water from phosphates and concentration of phosphates in purified water that can be used for the development of new techniques. Analytical laboratory data of the current purification station were carried out with the use of the Pearson correlation coefficient to detect a connection between concentration of phosphates in the purified water and four kinds of hydrobiological data using Microsoft Excel a computer program with functions Corel batch analysis. The most informative for monitoring of purification from the phosphates is the indicator of the number of types of hydrobionts. Change of concentration of phosphates goes in antiphase to the amount of types of hydrobionts. Therefore, for the convenience of the users there was completed the visualization of the existing trend using the introduced by the authors index-modified number of hydrobionts. There was presented an algorithm monitoring the process of sewage purification from phosphates, which requires the creation of a database and preliminary plotting of dependence of phosphates Sf concentration on the number of hydrobionts NG. The further displaying of laboratory data indicator NG on the schedule allows to predict the expected concentration of phosphates Sf in purified sewage and in case of poor forecast to carry out operational actions. The survey is based on the basis of a new methodology, which was transferred for the introduction to "Chernihivodokanal" (Chernihiv, Ukraine)
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 48-50; doi:10.21303/2585-6847.2017.00478

Abstract:
The problem of turbine engines blades stress-strain state has been studied. All calculations have been provided for the cooled blades constructions, used in the turbo machinery manufacturing. The investigation’s purpose was to develop the new adaptive mathematical model of turbine engine bladed disks with circular damping links stress-strain state by means of finite elements method. The foregoing approach to the finite elements method was borrowed from the literature on finite elements method. The main mathematical models and some types of the finite elements can’t be used for the correct description of the foregoing problem. The matter is that turbine blades have constructional non-homogeneity, which hardly ever could be correctly explained, using well-known finite elements and their mathematical dependences. On the other hand the variable aerodynamic force influence has also been taken into consideration. That is why the new model, which consists of sections, including disk’s sector, the whole blade and parts of damping links, has been developed. The finite elements methodology has been used for the dynamic stresses of this section calculation. Such approach gives an opportunity to describe the stress-strain state of the whole bladed disk as the superposition of the developed sections
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 51-53; doi:10.21303/2585-6847.2017.00487

Abstract:
The conditional stability of steady motions of a mechanical isolated system consisting of a rotating carrier body, a material point creating its static imbalance, and a passive automatic balancer consisting of two identical mathematical pendulums are investigated. The pendulums are mounted on the longitudinal axis of the supporting body and move in the plane of static imbalance. The relative motion of the pendulums is impeded by viscous drag forces. It is established that in the case when the imbalance is and the pendulums can eliminate it with a certain margin, there is one basic movement; in the absence of imbalance, there is a one–parameter family of basic movements; in the case of maximum unbalance, which pendulums can eliminate, there is one basic movement, but it generates a pseudo–family of basic motions. It is also established that conditionally asymptotically stable are separate basic motions, if they are isolated, or a family, or pseudo–families of basic motions. For pendulum, ball and liquid automatic balancers, an approximate law is obtained for the variation of large nutation angles in the case of an axisymmetric and non–axisymmetric supporting body. It is established that the rate of change of the nutation angle is significantly affected by the ratio between the axial moments of inertia of the rotating carrier and the coefficient of viscous drag. An empirical formula is proposed for estimating the residual nutation angle, which occurs when the passive automatic balancers (nutation dampers) are incorrectly installed on the spacecraft and stabilized by rotation, and an example of its application for a particular satellite is given. It is shown that incorrect installation of the auto balance on the supporting body can lead to the formation of a residual nutation angle even in the case of a "stable" supporting body. The obtained results can be used in the design of passive automatic balancers (nutation damping) (pendulum, ball and liquid) for spacecrafts stabilized by rotation
Eugenia Beletskaya, Aleksandr Ogar
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 3-5; doi:10.21303/2585-6847.2017.00484

Abstract:
The article deals with the problems of ensuring environmental safety and environmental protection, economic prerequisites for irrational nature management. The economic development of terrestrial civilization is associated with the accelerating growth of consumption of natural resources of the planet, as a result of which depletion of stocks of non-renewable types of natural raw materials and deterioration of the state of the environment as a result of intensive nature management and its environmental impact. To mechanize work in huge quantities, energy resources are consumed, natural landscapes change, artificial landscapes arise due to waste storage, hydrogeological regimes of rivers, lakes and territories change, climate changes and the reverse effect of the forces of nature. Development is accompanied by the involvement of natural resources in operation in ever increasing volumes and scales. The necessity of rethinking the technogenic and ionosphere civilization concepts of human development from the point of view of ecological safety is considered. The effectiveness of the approach to the management of ecological and economic systems is that there will be stabilization and improvement of the ecological status, preservation of unique natural objects, environmental safety of the population, sanitation of environmentally harmful and hazardous industries will be ensured. The transition to low-waste and non-waste technologies will become more real
Olena Veselova
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 6-8; doi:10.21303/2585-6847.2017.00475

Abstract:
The possibilities of mutual dependence of the areas of genetic types and varieties of the soil cover of the intensively developed region of the Northern Black Sea Coast with taxonomy of geomorphologic zoning, with morphogenetic categories of the relief of the earth's surface, with separate topographical and genetically homogeneous surfaces, with simple and complex surfaces of different morphology, exposition, morphometric parameters (vertical and horizontal dismemberment, steepness of the slopes) are considered and analyzed. The relevance of this approach is important and timely, given the presence of a number of problems in the Ukrainian economy. The study is carried out both in the territory of the regions a whole and in key areas, which in general represent the most revealing features of orographic, geomorphologic and paleogeographic character, distribution and quality of soil cover. Thanks to the analysis of the theoretical and methodological representations, an algorithm for the ecological and geomorphological analysis of the formation is used and degradation of the soil cover in the central part of the Northern Black Sea Coast is developed, based on the provisions of the philosophical vision of scientific knowledge. This report presents a step-by-step consideration, based on the example of the investigated territory, the diverse cartographic information chosen and analyzed in the context of the message topic, in conjunction with the properties of the soil cover of the region
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 27-30; doi:10.21303/2585-6847.2017.00476

Abstract:
Currently, metallurgists are trying to improve mechanical properties of steel by increasing alloy elements in it that require slow cooling in oils or high concentration of water polymers solutions. The paper discusses opposite way in increasing service life of machine components by cardinal decrease alloy elements in steel and providing intensive cooling in locally agitated plain water performed by moving sprayers. The proposed new approach is based on two fundamental phenomena which include creation of high surface compressive residual stresses after quenching and obtaining super - strengthened material in surface layers after intensive cooling. These two factors compensate decrease alloy elements in steel. The paper provides methodology of calculation for achieving maximal effect in residual surface compressive stress formation and super- strengthening of material depending on martensite finish temperature of steel. Effectiveness and benefits are considerable due to saving alloy elements, energy and increasing service life of products. A team of Ukrainian leading specialists is organized to design appropriate software for governing and optimizing hardening processes with the aim of achieving above benefits and make environment clean. New steel and technology of hardening is based on UA Patents No. 109577 and No. 114174
Dmitry Tatievskyi
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 37-39; doi:10.21303/2585-6847.2017.00482

Abstract:
Mathematical models of a road train are developed to study both its direct and reverse motion. The laws for the automatic steering system turning vehicle steering wheels to achieve the required trailer direction when moving reverse are synthesized. A road train with a hitching unit on the tractor truck rear axle directly schematic constructions (an “on-axle hitching” model) are used. The kind of kinematic mathematic model for describing a road train moving reverse at low speeds without wheels side slipping is satisfactory. In this condition its motion is defined by geometry only independent from masses, momentums and friction forces. The steering laws are synthesized with the help of alpha-stabilizing approach, according to Lyapunov’s direct method using fuzzy logics mathematical tool and a solution method depending on the Riccati equation state (SDRE). The task of reaching a set goal has been solved by calculating the folding angle when the target belongs to the calculated path for the case of curvilinear motion and via calculating the matching tractor truck and trailer orientation angles for direct motion. The received results have been rendered as phase portraits in the Maple environment and meshes in Meshlab, simulated in Unity 3D and with a robotic installation getting control information generated automatically
Igor Kozarchuk
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 15-17; doi:10.21303/2585-6847.2017.00477

Abstract:
The problems of mathematical modeling of hydrodynamics of open flows are analyzed in the article when general sizes of bridge crossings with group holes are assigned. Most of the existing methods for calculating branched flows are based on the use of one-dimensional models, it does not allow to describe sufficiently the hydrodynamic processes occurring in zones with separated flows. Therefore, in the calculation of bridge crossings with group holes, two-dimensional models that take into account the features of the morphology of natural watercourses, the uneven distribution of the average velocities along the vertical, the phenomenon of flow separation, as well as the change in rate along the flow due to the separation of the flow is suggested. The existing experimental and theoretical studies are analyzed, the flow structure and the physical model of the flow branching process in the zone of influence of bridge crossings with group holes are considered. Based on the fundamental equations of flow transfer, a mathematical two-dimensional model of the flow of open flows is presented, which takes into account the influence of secondary currents. To substantiate the zone of influence of bridge crossings with group holes, an equation for vorticity is proposed that reflects the distribution of vortex structures. For the closure of the equations of motion and continuity, algebraic relations for the Reynolds stresses in conjunction with the two-parameter k-ε model for depth-averaged values are used, which is modified to take into account the effect of the curvature of the flow. The method of numerical realization of the proposed mathematical model is based on the predictor-corrector method using the McCormack scheme, modified by splitting the model equations with respect to spatial coordinates and time. The method of successive upper relaxation based on the Gauss-Seidel iterative method is used to realize the algebraic relations of turbulent stress transfer. The conclusion is made about the expediency of practical application of this model
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 34-36; doi:10.21303/2585-6847.2017.00469

Abstract:
Technologies for computer analysis of visual information based on convolutional neural networks have been widely used, but there is still a shortage of working algorithms for continuous unsupervised training and re-training of neural networks in real time, limiting the effectiveness of their functioning under conditions of nonstationarity and a priori uncertainty. In addition, the back propagation method for learning multi-layer neural networks requires significant computational resources and the amount of marked learning data, which makes it difficult to implement them in autonomous systems with limited resources. One approach to reducing the computational complexity of deep machine learning and overfitting is use of the neural gas principles to implement learning in the process of direct information propagation and sparse coding to increase the compactness and informativeness of feature representation. The paper considers the use of sparse coding neural gas for learning ten layers of the VGG-16 neural network on selective data from the ImageNet database. At the same time, it is suggested that the evaluation of the effectiveness of the feature extractor learning be carried out according to the results of so-called information-extreme machine learning with the teacher of the output classifier. Information-extreme learning is based on the principles of population optimization methods for binary coding of observations and the construction of radial-basic decision rules optimal in the information criterion in the binary Hamming space. According to the results of physical modeling, it is shown that learning without a teacher ensures the accuracy of decision rules to 96.4 %, which is inferior to the accuracy of learning with the teacher, which is equal to 98.7 %. However, the absence of an error in the training algorithm for the backward propagation of the error causes the prospect of further research towards the development of meta-optimization algorithms to refine the feature extractor's filters and parameters of the unsupervised training algorithm
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 42-44; doi:10.21303/2585-6847.2017.00474

Abstract:
The article considers a new calculation method for determining the ship's maneuvering elements (inertial-braking characteristics) using an alternative approach. Based on the new methodology, the procedure for calculating the inertial-braking parameters of the ship is given. Within the framework of this task, an alternative approach is considered for determining the inertial-braking characteristics of a ship. The article shows that the entire braking process is divided by speed into several elementary sections and it is assumed that in each section the work of the resistance forces and the propeller stop is equal to the work of their average valuesand. And as an alternative method for determining the characteristics of the slowed and accelerated motion of the ship and its characteristics of active braking, theorems on the change in the amount of motion and kinetic energy are used. As a result, expressions of the braking time t and the coasting time S are obtained. Using the obtained expressions, an example of calculating the length and time of the coasting with active braking in the reverse direction from full forward to "full reverse" is given
Taras Nyzhnyk
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 54-56; doi:10.21303/2585-6847.2017.00486

Abstract:
Titanium compounds are very perspective reagents for water treatment because of their many outbreaking benefits compared to traditional coagulants – smaller dosage, lesser pH-dependency, they are biologically inert, work at low water temperature. But they have some technological issues, preventing them from wide use. One of the ways to overcome this issues shown in this article. Results of use of nanoencapsulation of Ti(IV) salts into solvable cells shown. This way allows to overcome problem with too quick hydrolysis and evenly distribution of coagulant in treated water. Also titanium coagulant was practically compared to traditional coagulant to show benefits of titanium-based coagulants
Ruslan Markul,
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 45-47; doi:10.21303/2585-6847.2017.00483

Abstract:
In the track facilities over the past decade, the polygon for laying reinforced concrete crossties has significantly expanded for many reasons. The main ones are the shortage of wooden crossties, their high cost and low life. Due to frequent crossovers, the service life of wooden crossties in the curved sections of the track R≤350 m is only 7 years. This is 5 times less than the life of reinforced concrete crossties. In the curves R≤350 m under the action of the rolling stock, an intensive accumulation of residual deformations occurs, which causes a violation of the track geometry in the plan. Simultaneously, the stability of the assembled rails and crossties in the transverse plane decreases. Given the shortcomings of the railway track on wooden crossties, a study is conducted to solve the problems of geometry, and the stability of the track in the transverse horizontal plane. To achieve this, the design of the fastener assembly KПП–5 (SB–3) has been improved, which makes it reliable and adjustable in all respects for 800 1000 million of tons of bruto. In order to ensure the stability of the track, an anchor crosstie structure has been created which can increase the resistance to transverse displacement of the assembled rails and crossties more than 2 times. The developed and justified measures will allow to create a highly efficient construction of a seamless track with reinforced concrete crossties and КПП–5 (SB–3) fastener for curved sections with a radius of 350 ÷ 200 m. When considering these proposals with the possibility of practical use, it becomes possible to introduce a safe and reliable design of continuous welded rail track with КПП–5 fastener assembly in difficult operating conditions
Maksym Iasechko
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 18-20; doi:10.21303/2585-6847.2017.00480

Abstract:
The urgency of the improvement of methods and means of protection of radio electronic means (REM) due to the development and application of high–power electromagnetic radiation (EMR) generators with ultrashort pulses duration (UPD) is substantiated. It is pointed out that it is possible to solve the problem of REM protection by the complex application of plasma technologies using gaseous and modified solid–state media. By analyzing the known achievements in the field of developing effective methods and creating protection facilities for REM, a number of unresolved problems in the field of creation of plasma protection technologies have been determined. The technique of solving the formulated problems is presented and the main relations are obtained to determine the expediency of using the proposed technology in the interests of the REM integrated protection from the powerful EMR UPD. A relation is made for the breakdown criterion in a gaseous plasma medium that relates the value of the breakdown field to the concentration of charged particles determined by the ionization source. The structure of a solid–state plasma medium is described, which can be used as a protective shield. The order of finding the REM screening coefficient is shown, based on the determination of the distribution function of charged particles for finding the main macroscopic properties of plasma by solving the kinetic equation of the Lenard–Balescu equation. A relation is given for the damping coefficient of an electromagnetic wave in solid–state plasma. Numerical estimates are presented in the form of graphs showing the possibility of using plasma technology to protect the REM from a powerful EMR through possible channels of penetration. The discussion of the obtained results is presented and it is indicated on the possibility and prospects of using the proposed technology for REM protection, especially with limitations on the weight dimensions of protection devices
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 31-33; doi:10.21303/2585-6847.2017.00471

Abstract:
Dichotomizing algorithms of diagnostics and reconfiguration of the navigation system which process indicators of inertial, satellite and optical subsystems in real time for typical types of refusals are considered in the work. The given approach provides majority diagnostics of measuring system with system and hardware redundancy at a minimum necessary set of sensors. The main idea of a method is the comparative analysis of all measuring subsystems behind reference value. The reference value is the parameter which is synthesized from all diagnosable subsystems, in this work – a course corner. When obtaining the only parameter by gages of the different nature it is possible to provide firmness of an algorithm. Also reasonably the possibility of the introduction of optical systems with the use of algorithms of computer sight for ensuring system redundancy of the navigation system is described. The system is intended for identification only of one type of refusal for a unit of time. A positive factor of an invention is the universality that allows using system on any operating small autonomous aircraft. For the introduction of a system, there is no requirement in finishing the hardware. Use of system of failure diagnostics will reduce the risk of loss of the aircraft when performing a task, will increase its efficiency and accuracy of indicators. As a result of researches, the algorithmic dependence of signals of the navigation system was established that allowed to make the analysis and diagnostics with the following renewal of the lost parameter thanks to system and hardware redundancy of devices. Practical use of the system in actual practice with an influence of artificially created obstacles and noise is shown. Developments in area of aircraft safety are necessary due to the need for an increase in level, at the emergence of emergency situations
, Oleksii Rezydent
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 40-41; doi:10.21303/2585-6847.2017.00472

Abstract:
One of the main constructive elements of roadmakers, railway bridge supports and structures is a compressed rod, to the end of which a follower force is applied. Recently, the most frequently used model of such rod in the form of an inverted mathematical pendulum under the influence of an asymmetric follower force. Asymmetry is due to the simultaneous presence of both angular and linear eccentricities. The work is devoted to the study of vertical and non-vertical states of equilibrium of a single pendulum. The reduced mathematical model of a single inverted mathematical pendulum is generalized, since it takes into account both the angular eccentricity and the linear eccentricity of the follower force. In addition, the coefficients of influence allow to consider all types of elastic elements (rigid, soft or linear). In this case, both elements can have characteristics of the same type or of different types. For direct integration of the differential equation of the pendulum motion, and also the decoupling of the corresponding Cauchy problem, the authors use the method of extending the parameter of the outstanding Japanese scientist Y.A. Shinohara. Varying of the angular eccentricity of the follower force at zero linear eccentricity results in the inverted pendulum having one or three non-vertical equilibrium positions. The type of characteristics of the elastic elements affects the maximum possible deviation from the vertical, at which the pendulum will be in a state of equilibrium. Analysis of the results of computer simulation shows that the orientation of the follower force for fixed values of other parameters of the pendulum has a significant effect on the configuration of the equilibrium curve
Iryna Halushchak
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 12-14; doi:10.21303/2585-6847.2017.00473

Abstract:
To reduce the metal consumption of boilers of steam-turbine power units and waste-heat boilers of gas-steam turbine units, the spiral-tape finning of low-temperature convection heating surfaces is applied. However, the heat transfer in the bundles of such tubes has not been studied sufficiently, the influence of the geometric dimensions of the cut portion of the fins has not been experimentally investigated. In most heat exchange calculation methods, based on the generalization of the results of experimental studies, this influence is also not taken into account. It is proposed to take into account the influence of the finning geometry on heat transfer by introducing correction coefficients in the generalizing equations, determined from the results of a numerical research. To evaluate the validity of the introduction of the results of numerical research into generalizing equations, an experimental investigation of heat exchange in the interfin channels of the punched spiral finning of the tubes is carried out. A research method is developed based on the results of measurements of the surface temperatures of the fins and air in different zones of the interfin channel along its height, as well as the air temperature in front of the bundle and the air flow through the bundle. The study is carried out by placing the calorimeter tubes in the transverse rows of the chess and corridor bundles of tubes at different Reynolds numbers. The results of the investigation of one of the bundle. The calorimeter is installed in the fifth row of a six-row tube bundle with fin interval of Sf = 6 mm and tube steps in the bundle S1 = 85 mm, Ś2 = 85 mm. At the Reynolds number, Red = 10042: the heat flux in the interfin channels Q = 711.0 W, the same according to electrical measurements - 731.0 W; discrepancy - 2.73 %; the heat transfer coefficient in the blade zone is αifcb = 162.0 W/m2°C; discrepancy – 2.88 %. The average surface heat transfer coefficient in the interfin channel is ͞ αifc = 132.35 W/m2°C; by numerical calculation - 122.6; discrepancy is 7.31 %. The average surface heat transfer coefficient of a single transverse row of tubes, taking into account the flow of a part of the air through the intertubular channels, is ͞ αc = 83.05 W/m2°C; the discrepancy is 5.12 %. In the remaining experiments, the difference in the values of the heat transfer coefficients is 3.19 ... 15.7 %. The results of the investigation confirm the validity of the use of the results of numerical investigation in generalizing equations for calculating the heat transfer of bundles of tubes with a spiral finning
Ludmila Andriievska
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 21-23; doi:10.21303/2585-6847.2017.00470

Abstract:
The article is devoted to the research of the acrylic artificial stone properties, which has wide application in the production of furniture, in particular for the bathroom (sinks, baths), kitchens (sinks, countertops, bar counters, table tops for dining tables) and decorative interior elements (window sills, wall panels). In the Ukrainian market there are products of well-known world producers of acrylic artificial stone TM "Corian" (DuPont, USA), "Polystone" (China), LG Chem (South Korea), "Staron" and "Tempest" (Samsung Cheil Industries Inc , South Korea), HI-MACS (LG, South Korea), GetaCore (Westag & Getalit AG, Germany), and unknown trademarks, whose quality of goods is doubtful for the consumer. Therefore, it became necessary to study the acrylic artificial stone properties of those producers whose products are most in demand in the domestic market. For the research, samples of five manufacturers of acrylic artificial stone TM Tristone (South Korea) Bitto Dongguan (China), Corian (USA), Polystone (China) and LG Ni-macs (South Korea) were selected. These samples of acrylic artificial stone were tested by standard methods for the following parameters: density, water absorption, compressive strength, flexural strength, impact resistance, wear resistance, Mohs hardness, chemical resistance and compared with standards. Based on the research results, samples of acrylic artificial stone have been determined that do not meet the requirements of regulatory documentation, and recommendations have been made on the use of the investigated materials, taking into account their intended use, providing high performance, reliability and durability
Technology transfer: fundamental principles and innovative technical solutions, Volume 1, pp 24-26; doi:10.21303/2585-6847.2017.00481

Abstract:
The authors analyzed the foreign experience of using keyed joints in reinforced concrete span structures of bridges. Fiber concrete with polypropylene fibers was chosen as the investigated material. Such fibers are chemically neutral, water-resistant, have a high resistance to dynamic loads, reduce the risk of formation and development of cracking, increase abrasion what is important in the manufacture of road construction. Optimization of concrete composition with polypropylene fibers for concreting joints by physical and mechanical parameters was carried out. Parameters of optimization were compressive strength, tensile strength at bending, axial tensile strength, prism strength and abrasion. The authors performed a series of tests to study the behavior of fiber concrete in keyed joints. The analysis of obtained results out depending on the nature of failure, the value of the ultimate load and fiber concrete deformations were carried out. The influence on the joints strength of the cross-section reinforcement percentage and the nature of placement of the reinforcing rods was considered. It was established if to place a cross-reinforcement in two levels it increases the strength of joints in comparison with a single level with the same percentage of reinforcement. It was noted that the fracture of all samples occurred from the sear key. Cracking of fiber concrete experimental samples occurred at later stages of loading compared with samples of ordinary concrete, and the fracture was not brittle, without tearing off parts of concrete. Increase in strength is due to the chaotic placement of polypropylene fibers in concrete, and therefore, to remove fibers from concrete, it is necessary to spend more energy, which ultimately leads to an increase in strength of joint. Experimental data suggest possibility and feasibility of polypropylene fibers in concrete joints in precast concrete structures of bridges
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