Eastern-European Journal of Enterprise Technologies
http://journals.uran.ua/eejet
<p><span lang="EN-US">Terminology used in the title of the "Eastern-European Journal of Enterprise Technologies" - "enterprise technologies" should be read as "industrial technologies". <strong>"Eastern-European Journal of Enterprise Technologies"</strong> publishes all those best ideas from the science, which can be introduced in the industry. Since, obtaining the high-quality, competitive industrial products is based on introducing high technologies from various independent spheres of scientific researches, but united by a common end result - a finished high-technology product. Among these scientific spheres, there are engineering, power engineering and energy saving, technologies of inorganic and organic substances and materials science, information technologies and control systems. Publishing scientific papers in these directions are the main development "vectors" of the "Eastern-European Journal of Enterprise Technologies". Since, these are those directions of scientific researches, the results of which can be directly used in modern industrial production: space and aircraft industry, instrument-making industry, mechanical engineering, power engineering, chemical industry and metallurgy.</span></p><p><span lang="EN-US">Therefore, the scientists, associated with modern production, have the opportunity to participate in technology transfer to industry, publishing the results of their applied scientific researches. Industrialists, in turn, can draw scientific and practical information from the journal - each in their direction:</span></p><ul><li>specialists in management and computer science - from volumes "Applied Information Technologies and Control Systems", "Mathematics and Cybernetics - Applied Aspects";</li><li>mechanical and design engineers - from the volume "Applied Mechanics";</li><li>production engineers - from volumes "Mechanical Engineering Technology", "Applied Physics", " Materials Science", "Technology of organic and inorganic substances and the Ecology";</li><li>production and power engineers - from the volume "Energy-saving technology and equipment".</li></ul><p><span lang="EN-US">The goal of the journal is to eliminate the gap, which occurs between the rapidly emerging new scientific knowledge and their introduction in the industry, which requires much more time. Industrial enterprises are active subscribers to the "Eastern-European Journal of Enterprise Technologies", and production engineers check the practical value of those scientific and technological ideas, which are recommended for implementation by scientists-authors of the ''Eastern-European Journal of Enterprise Technologies".</span></p><p><span lang="EN-US">The objective of the journal in achieving the goal is forming a "scientific component" of modern technologies transfer from science to industry. Therefore, in the papers, published in the journal, the emphasis is placed on both scientific novelty, and practical value.</span></p>PRIVAT COMPANY "TECHNOLOGY CENTER"en-USEastern-European Journal of Enterprise Technologies1729-3774<p>Our journal abides by the CREATIVE COMMONS copyright rights and permissions for open access journals.</p><p>Authors, who are published in this journal, agree to the following conditions:</p><p>1. The authors reserve the right to authorship of the work and pass the first publication right of this work to the journal under the terms of a Creative Commons Attribution License, which allows others to freely distribute the published research with the obligatory reference to the authors of the original work and the first publication of the work in this journal.</p><p> 2. The authors have the right to conclude separate supplement agreements that relate to non-exclusive work distribution in the form in which it has been published by the journal (for example, to upload the work to the online storage of the journal or publish it as part of a monograph), provided that the reference to the first publication of the work in this journal is included.</p>Development of information technology elements for decision-making support aimed at re-structuring production at virtual instrument-making enterprises
http://journals.uran.ua/eejet/article/view/182039
This paper considers issues related to the re-structuring of virtual industrial enterprises, in particular the prospects for developing a virtual instrument-making enterprise (VIE). Such enterprises operate by employing external geographically distributed resources and could be flexible in terms of making a product demanded by market. We have proposed elements of information technology (IT) to support decision making on the organization of VIE operation. The IT elements include models and structures for decision making, including those aimed at the rational use of resources in the operation of VIE. The purpose of the proposed IT is to solve a task on supporting decision-making in the restructuring of production processes at virtual instrument-making enterprises based on market conditions. The need for re-structuring of production is caused by difficult conditions of market economy for small and medium instrument-making enterprises. A production program is formed on the basis of the currently existing demand for different categories of articles included in the product range of an enterprise, or correspond to the direction of VIE operation. The IT elements include models for an informational-analytical portal (IAP), as well as a block diagram for deploying and supporting a unified knowledge space, at flexible re-structuring of production according to market conditions. The IAP also includes expert systems (ES). The designed IT for a decision-making support to a VIE head would make it possible to produce the product demanded in the market and profitable in manufacture. IT could enable determining the number and types of necessary resources according to the assigned criteria, their distribution, taking into consideration a direction of production re-structuringAndrii SobchakLiudmyla LutaiMykola Fedorenko2019-10-292019-10-29512 (101)536210.15587/1729-4061.2019.182039Development of a price optimization algorithm using inverse calculations
http://journals.uran.ua/eejet/article/view/180993
<p class="references">An algorithm is proposed for solving the price optimization problem using inverse calculations. The algorithm includes two stages: solving the problem of unconditional optimization and solving the inverse problem using inverse calculations while minimizing changes in the arguments of the function. In this case, the solution of the inverse problem can be performed repeatedly within a given number of iterations to sequentially approach the set value of the constraint, and to determine the increment of the arguments, the values of the elements of the gradient/anti-gradient vector of the constraint function are used. To take into account the influence of the arguments on the change of the objective function, its second partial derivatives are used. Five options of the price optimization problem are considered, which nonlinear programming tasks with one restriction are. The revenue of the enterprise, the deviation of demand from the volume of production, the deviation of the sought price from its current value are considered as the objective function. It is shown that the solutions obtained in this way are consistent with the result of using classical methods (Lagrange multipliers, penalties), and the results are also compared with solving problems using the MathCad mathematical package. The advantage of the method is a simpler computer implementation, the ability to obtain a solution in fewer iterations compared to known methods. The method can also be used to solve other problems of the presented type with the following requirements for the objective function and restrictions:</p><p class="references">1) partial derivatives of the objective function of the first order – linear one-dimensional functions;</p><p class="references">2) the restriction has the form of equality;</p><p class="references">3) the constraint is linear or the constraint is quadratic, and the partial derivatives of the first order of the constraint function are one-dimensional linear functions.</p>The article may be useful for specialists making decisions in the field of pricing policies of organizations, as well as the development of optimization models of economic facilities and decision support systemsEkaterina Gribanova2019-10-292019-10-29512 (101)182510.15587/1729-4061.2019.180993Implantation of indexing optimization technology for highly specialized terms based on Metaphone phonetical algorithm
http://journals.uran.ua/eejet/article/view/181943
When compiling databases, for example to meet the needs of healthcare establishments, there is quite a common problem with the introduction and further processing of names and surnames of doctors and patients that are highly specialized both in terms of pronunciation and writing. This is because names and surnames of people cannot be unique, their notation is not subject to any rules of phonetics, while their length in different languages may not match. With the advent of the Internet, this situation has become generally critical and can lead to that multiple copies of e-mails are sent to one address. It is possible to solve the specified problem by using phonetic algorithms for comparing words Daitch-Mokotoff, SoundEx, NYSIIS, Polyphone, and Metaphone, as well as the Levenstein and Jaro algorithms, Q-gram-based algorithms, which make it possible to find distances between words. The most widespread among them are the SoundЕx and Metaphone algorithms, which are designed to index the words based on their sound, taking into consideration the rules of pronunciation. By applying the Metaphone algorithm, an attempt has been made to optimize the phonetic search processes for tasks of fuzzy coincidence, for example, at data deduplication in various databases and registries, in order to reduce the number of errors of incorrect input of surnames. An analysis of the most common surnames reveals that some of them are of the Ukrainian or Russian origin. At the same time, the rules following which the names are pronounced and written, for example in Ukrainian, differ radically from basic algorithms for English and differ quite significantly for the Russian language. That is why a phonetic algorithm should take into consideration first of all the peculiarities in the formation of Ukrainian surnames, which is of special relevance now. The paper reports results from an experiment to generate phonetic indexes, as well as results of the increased performance when using the formed indexes. A method for adapting the search for other areas and several related languages is presented separately using an example of search for medical preparationsVolodymyr BuriachokMatin HadzhyievVolodymyr SokolovPavlo SkladannyiLidiia Kuzmenko2019-10-292019-10-29512 (101)435010.15587/1729-4061.2019.181943Forming a мetodology for transforming a model as the basis for expanding its informativeness
http://journals.uran.ua/eejet/article/view/181866
<p>A problem on building the methodology for transforming the implicit form of a model has been stated and solved, which improves the efficiency of replacing complex nonlinear forms of mathematical models to reducing them to a recurrent sequence in the form of analytical expressions that allow quick express calculations.</p><p>New explicit forms of the models have been proposed that make it possible to use recurrent sequences for representing a solution to the problem and forming an error estimation expression, as well as and additional information. Given the fact that for many attributes the solution and an error estimation are critical, the analyticity of expressions reveals new properties and possibilities. Based on such factors as authenticity, accuracy, depth, materiality and completeness, the adequacy of the model is represented by a single analytical expression that would make it possible in future to simplify the process of comparison through the use of quantitative methods. Representation of transformations, according to which the connection between the error of two consecutive approximations and dependence on the approximation number was established, is predetermined by the necessity to analyze convergence dynamics based on the iteration number. Another variant, not less important, which can characterize the dynamics of convergence is the connection between an error of the first approximation and the arbitrary approximation. Based on the overall expansion of the implicit form of the model and the mean value theorem, the relationship between the two consecutive errors or norms has been established. It is demonstrated that if the error or a norm of error are assigned, the estimates for the first and second derivatives would make it possible to determine the boundary number of the iteration starting from which the error is less than the assigned one.</p><p>An example has been given for deriving an estimation for the general model of the magnitude of a maximally possible error, the boundary number of the iteration, starting from which the error acquires a value less than the assigned one. A comprehensive analytical assessment of adequacy based on a single expression has also been derived.</p><p>Representation of informational attributes in the quantitative form is predetermined by new opportunities that would emerge due to the obtained tools for quantitative analysis.</p><p>Numerical modelling has been performed; the character of dynamics of new informational indicators and attributes has been examined. The data given for nine iterations demonstrate efficiency and completeness of information to perform a quick analysis and draw a conclusion. Based on the dynamics of quantitative attributes for a relative error, as well as new ones, proposed based on the results from implementing the model transformation methodology, it has been shown that the possibilities emerge to run a quick analysis and draw a conclusion. It was demonstrated that the introduced attributes expand the informativeness of the methodology implementation for the further representation of a nonlinear model in the form of a recurrent sequence</p>Alexander Trunov2019-10-282019-10-28512 (101)344310.15587/1729-4061.2019.181866Construction of an algorithm for building regions of questionable decisions for devices containing gases in a linear multidimensional space of hazardous factors
http://journals.uran.ua/eejet/article/view/181668
The issue of danger emanating from industrial devices with combustible gases has been considered in the linear multidimensional continuous space of dangerous factors. Dangerous factors are categorized into factors associated with industrial devices and the physical-chemical properties of gases that these devices contain. The actual existing combustible gases are characterized by numerical discrete properties such as molecular mass, specific heat of combustion, etc. An abstract model space of gases is represented in the space of dangerous factors by points whose coordinates are the physical-chemical properties of gases. Given the continuity of the space of dangerous factors, actual gases will be represented by individual points within this space or regions in which certain properties, for example temperature, density, volume, are continuously changing. In addition, there would be a large number of points at which the properties of gases are incompatible, that is such that are impossible for real gases. This has allowed us to consider the issue of danger emanating from combustible gases from some general positions. Thus, using the methodology of p-functions has made it possible to split the space of dangerous factors into dangerous and safe parts. It was also possible to identify the border regions in which the task of determining the hazard from a device is incorrect. That means that some variation of dangerous factors within the accuracy known about them leads to different, mutually exclusive conclusions about danger. Such areas are termed the regions of questionable decisions. It has been found that the regions of questionable decisions may be complex in shape and their size depends on the accuracy that is inherent in the quantitative values for dangerous factors. An algorithm for constructing regions of questionable decisions has been developed that could define whether a device containing gas belongs to a region of questionable decisions. It has been shown that determining whether a device is associated with a region of questionable decisions is a numerical problem with an unambiguous solutionAlexey TeslenkoAnton ChernukhaOleg BezuglovOleg BogatovEkaterina KunitsaViktoriia KalynaAlbert KatuninVolodymyr KobzinSergey Minka2019-10-252019-10-25512 (101)424910.15587/1729-4061.2019.181668Minimization of transportation risks in logistics by choosing a cargo delivery route with the minimal projected number of road accidents
http://journals.uran.ua/eejet/article/view/181612
<p>A scientific-methodological approach to selecting a route with a minimal projected number of road accidents among several possible routes that connect the points of departure and destination has been proposed, which is based on three steps: the first step implies building a directed graph that contains the points of departure, delivery, as well as intermediate points, which are linked by edges with the specified distances between the points; the second step implies the calculation of the projected number of road accidents for each edge as the product of the distance that a truck must travel over a specific region by a road accident indicator, which is calculated for a given region; at the third step, a route is determined with the minimal projected number of road accidents.</p><p>A decision maker can be guided by two strategies: a first strategy is to choose the shortest delivery path – this would minimize the cost of delivery; a second strategy is to choose a route with the minimal projected number of road accidents ‒ this minimizes accidents indicators. The current study has stated the problem of multifactor optimization based on distance and the projected number of road accidents and has proposed a Pareto-optimal solution.</p><p>The proposed method could prove useful for operations by transportation and logistics enterprises when substantiating the safest routes to deliver cargoes, taking into consideration the importance of minimizing the cost of delivery.</p>The software for interactive maps and navigation systems includes widely known methods for determining the shortest distance, a route that takes minimum time, or a route that avoids "traffic jams". It has been proposed to consider adding the algorithm, which was developed based on the proposed method for choosing a route with the minimal projected number of road accidents, as one of the alternatives to choose the optimal routeMykhailo OklanderOksana YashkinaDmytro Yashkin2019-10-252019-10-25512 (101)576910.15587/1729-4061.2019.181612Studying the influence of metakaolin on self-healing processes in the contact-zone structure of concretes based on the alkali-activated Portland cement
http://journals.uran.ua/eejet/article/view/181501
<p>This paper reports results from comparative testing the reaction "alkali ‒ active silica" in traditional Portland cement and alkaline Portland cement with the addition of metakaolin. The research is based on studying the process of structure formation in cements in the contact zone "cement stone – basalt".</p><p>The research results allow us to conclude that the dynamics of the process of interaction of the reaction "alkali‒silica" in cements may be constructive and destructive in character. That depends on the content of components that are able to actively interact with alkalis in the presence of reactive silica. The so-called "constructive" processes are accompanied by the binding of corrosion products during the formation of alkaline hydroalumosilicates. The research results were used as the basis for developing the mechanism of preventing the reaction "alkali – active aggregate" in concretes based on alkaline cement by introducing to the cement composition additional amounts of materials containing active aluminum, in particular, metakaolin.</p><p>Our study has shown that the introduction of a metakaolin additive could effectively control the processes of structure formation in the contact area "cement stone – active silica", thereby changing the character of new structures. The mechanism of an alkaline corrosion process of an active aggregate in the presence of metakaolin has been established, according to which metakaolin enters the reaction at a rate of microsilica, providing for a very fast binding of the Na<sup>+</sup> and K<sup>+</sup> ions. Silicate gel of alkaline metals binds into insoluble zeolite-like new structures and hybrid hydroalumosilicates. As resilient structures, the latter condense and strengthen the contact area by enhancing its microhardness and strength.</p>We have investigated the natural shrinkage deformations (expansion) of the developed compositions of concretes based on the traditional and alkaline Portland cements. It has been shown that the introduction of a metakaolin additive to the system formulation makes it possible to reduce the system expansion indicators from 0.44 to 0.01 mm/m, thereby maintaining the defect-free structure of cement stone and concrete and improving the durability of concreteOleksandr KovalchukOleksandr GeleveraVasyl Ivanychko2019-10-242019-10-24512 (101)334010.15587/1729-4061.2019.181501Development of the method operative calculation the recurrent diagrams for non-regular measurements
http://journals.uran.ua/eejet/article/view/181516
<p>Researchers widely use methods for calculation of recurrence plots based on measurement of dynamics of a vector of states in a phase space for visual and quantitative analysis of the behavior of complex dynamic systems in various fields. Such methods have high potential capabilities. However, one cannot use them directly for the operative calculation of recurrence plots at the real speed of measurements of a vector of states, taking into account irregularity of measurements. One of the reasons is the lack of a method, which would be capable of operative and reliable mapping of recurrence states of real systems in recurrence plots at irregular measurements of a vector of states.</p><p>We propose a method for the operative calculation of recurrence plots at irregular measurements. Its base is a scientific analysis of reasons for low reliability and impossibility of an operative calculation of recurrence plots, as well as search and substantiation of constructive methods for their elimination. Such methods include: current calculation of recurrence plots; improvement of a phase space by introduction of an operation of scalar product for vectors of states; adaptation of a recurrence threshold to measurement results. The base of a process of the current calculation of recurrence plots is a use of only current and previous measurements of a vector of states of the system. It is possible to reconcile two key factors of low reliability of mapping of recurrence states in diagrams related to uncertainty of a norm and a threshold of recurrence in the proposed improved phase space.</p>The above has made possible to propose a threshold adaptation method for conical regions of recurrence. It has been proposed to use two adaptive thresholds with different angular parameters of recurrence cones in the calculation to ensure reliable mapping of recurrence states in diagrams under conditions of irregular measurement of a vector of states. We confirmed the operability of the proposed operative method for calculation of recurrence plots and illustrated it by an example with irregular measurements of the real dynamics of a vector of states of dangerous pollution in the urban atmosphereBoris PospelovOlekcii KrainiukovAlexander SavchenkoSerhii HarbuzOleksandr CherkashynSergey ShcherbakIhor RolinViktor Temnikov2019-10-242019-10-24512 (101)263310.15587/1729-4061.2019.181516Determining the source data to form a control algorithm for hydrogen generators
http://journals.uran.ua/eejet/article/view/181417
<p>Constructing an algorithm to control the technical condition of hydrogen generators employs using their amplitude-frequency and phase-frequency characteristics as the source data. Applying the classic method for defining such characteristics predetermines several drawbacks. One of the significant disadvantages is the long time required to form an array of source data. To shorten this time, determining the frequency characteristics of a hydrogen generator is carried out based on the results of measuring its transition function over discrete moments of time. During these time moments, the transition function is approximated by the Heaviside functions. Such an approach reduces the time for determining the frequency characteristics of a hydrogen generator by 1–2 orders. Applying the Kotelnikov–Nyquist–Shannon theorem for determining these discrete time moments is due to uncertainty about the maximum frequency of the test-signal spectrum.</p><p>To avoid this uncertainty, discrete time moments for measuring the transitional function of a hydrogen generator are chosen under condition for the permissible error of its approximation.</p><p>The error of approximation is determined based on the result from solving a test-problem that uses model characteristics as a standard for the frequency characteristics. It has been shown that at a sampling interval of (0.25¸2.5) ms the magnitude of such an error does not exceed 1.7 %.</p><p>Inertial properties of the device that forms a test-impact have been taken into consideration. It has been shown that it is appropriate to apply such a procedure if the equivalent time constant of such a device exceeds the magnitudes of time constants for a hydrogen generator. The inertial properties are taken into consideration by introducing an additional multiplier, which contains the equivalent time constant of the device, to the analytical expressions for the frequency characteristics of a hydrogen generator</p>Yuriy AbramovOleksii BasmanovValentina KrivtsovaAndrey MikhaylukOleksandra Mikhayluk2019-10-232019-10-23512 (101)586410.15587/1729-4061.2019.181417Improving contact durability of polycrystalline systems by controlling the parameters of large-angle grain boundaries
http://journals.uran.ua/eejet/article/view/181441
Polycrystalline metal systems in the samples made of steel 40X with different morphology and parameters of the distribution of large-angle grains boundaries for energy have been examined. The effect of the structural-energy state of grains boundaries on the operational reliability of improved steel 40X has been established. Based on the hierarchical modeling of polycrystals structure, new approaches have been proposed and algorithms have been developed for defining relationships between the structure that is formed in the technological processing of materials and stages in the life cycle of parts. It has been revealed that it is advisable to use, as a digital prototype of the structure of polycrystalline alloys that describes their performance under conditions of contact loads, the matrix representation of a system model that would incorporate the quantitative characteristics of grains. By using the devised procedures, the ways to execute technological control over the energy state of grain boundaries in the structural components have been defined in order to improve durability of parts exposed under contact loads. An estimation-experimental method has been developed to assess the effect of quantitative characteristics of the structure on the parameters of strength of the grains boundaries and their ability to form intragrain damage under external loads. The energy level of grains boundaries and triple joints between the groups of small and large grains is higher than that between grains of the same size. The boundary surfaces with a high level of energy are places where damage occurs at technological processing and under external loads on structural materials. This points to the crucial role of large-angle boundaries placed between triple joints with a high energy gradient in the process of forming microstructurally short cracks and intragrain destruction of polycrystalline systems. The use of hierarchical modeling methods and computational materials science makes it possible to improve the operational reliability of articles by choosing the optimal parameters for internal boundary surfaces. The lower cost of the parts' life cycle is achieved by thermal treatment regimes, which alter the quantitative characteristics of the steel structureViacheslav KopylovOleg KuzinNiсkolay Kuzin2019-10-232019-10-23512 (101)142210.15587/1729-4061.2019.181441A study of an electrochromic device based on Ni(OH)2/PVA film with the mesh-like silver counter electrode
http://journals.uran.ua/eejet/article/view/181396
<p>The study is devoted to the development and testing of the electrochromic device based on Ni(OH)<sub>2</sub>/PVA (polyvinyl alcohol) composite and mesh counter-electrode. A copper wire with a layer of electroplated silver layer is proposed as a mesh material. Glass coated with fluorine-doped tin oxide after special treatment was used as a substrate for electrochrome deposition. The treatment lies in the shallow dissolution of the surface by means of soft electrochemical etching. The distance between the mesh and electrochromic electrodes was small and equal to 1.5 mm.</p><p>The proposed design of the electrochromic device can lead to lower cost. However, it limits the range of possible applications for light windows or upper parts of view windows, building partitions.</p><p>Over the course of the studies, it was demonstrated that the electrochromic device is operational and can be used for further scaling. Parameters of electrochemical cycling – working voltage window and current density, were found. It was found that the use of galvanostatic regime for color switching results in linear characteristics of the device.</p><p>The use of the chosen voltodynamic regime results in a decrease of specific characteristics of the device – coloration degree and reversibility during bleaching.</p>It was found that due to the small potential difference of nickel oxide and silver electrodes, the polarity of voltage during coloration and switching changes. Additionally, it is noted that no gas evolution was observed over the course of the experimentsValerii KotokVadym Kovalenko2019-10-232019-10-23512 (101)495510.15587/1729-4061.2019.181396Development of a resource-process approach to increasing the efficiency of electrical equipment for food production
http://journals.uran.ua/eejet/article/view/181375
<p>Specific indicators of heat and electric power consumption per unit of food production have object-oriented properties, since they are determined on the basis of methods that are suitable only for a particular enterprise. It is shown that the system approach is the main approach to increasing the efficiency and reliability of electrical equipment.</p><p>The concept of increasing the efficiency of the use of electrotechnical equipment of food production by optimizing machine time is proposed. Methods for optimizing machine time for equipment utilization using a resource-process approach are developed. It is practically proved that by combining successive Gantt charts along the time axis from right to left, one can significantly reduce machine time for transferring raw materials. Thanks to the resource-process optimization, it became possible to significantly reduce the execution time of part of the technological task. Such a technique should be applied separately for all technological units that are consumers or sources of raw materials, followed by creating an integrated mathematical model and subsequent optimization.</p>As a result of testing the proposed method, energy saving was achieved by optimizing the time of use of the electrical equipment of the baking enterprise. It is found that due to reducing the significant total idle time of electric motors, inappropriate heating, cooling of furnaces and compressor operation, the efficiency of electricity use in food production is increasedNataliia ZaietsVolodymyr ShtepaPavel PavlovIhor ElperinMaryna Hachkovska2019-10-232019-10-23512 (101)596510.15587/1729-4061.2019.181375Development of mathematical models of gas leakage and its propagation in atmospheric air at an emergency gas well gushing
http://journals.uran.ua/eejet/article/view/179097
<p><span lang="EN-US">The study tackles the development of new mathematical means for determining distribution in space and time of technogenic load on atmospheric air as a result of non-burning gas well gushing. To date, modeling is the only tool for studying and solving pressing problems of environmental safety in operation of gas condensate fields. This is especially true for those issues that cannot be solved in practice, such as studying causes and predicting occurrence of emergencies with a low probability of occurrence but with heavy devastating consequences. Drawbacks of the existing mathematical models and methods which make impractical their use in modeling atmospheric pollution in the case of non-burning gas well gush were pointed out. The problem of forecasting the level and distribution of atmospheric air pollution in open gash of a gas well involves two steps: determining amount of gas releases, their parameters and composition; calculation of harmful substance scatter in the near-surface atmosphere. Physical peculiarities of the gas mixture movement through the well and distribution of pollutants in atmospheric air during non-burning well gushing were studied. Mathematical models of stationary and burst release of a mixture of gases from a well were constructed as differential equations with corresponding initial and boundary conditions. These models take into account all major factors affecting intensity of the gas mixture flow during an emergency gushing and adequately describe the process. A new mathematical model of pollutant spread in atmospheric air during release from a well has been constructed. This model, unlike the existing ones, is a set of three analytical dependences describing distribution of contaminants in space and time in the case of burst, short-term and continuous releases, respectively. The results of mathematical calculations were compared with the data of field measurements of concentration of pollutants that were part of the gas flow during emergency release at a gas condensate field in Poltava region. It was established that the modeling error did not exceed 15% for all substances under study. This comparison has confirmed high adequacy of the developed models and the possibility of their application to solving a wider (compared to existing models) class of problems related to monitoring the atmospheric air in the territories of gas wells under various release conditions, meteorological characteristics, and the drilling rig operation conditions</span></p>Teodoziia YatsyshynLesya ShkitsaOleksandr PopovMykhailo Liakh2019-10-222019-10-22512 (101)495910.15587/1729-4061.2019.179097Development of the procedure for simulation modeling of interrelated transport processes on the main road network
http://journals.uran.ua/eejet/article/view/179042
<p>The article deals with the interrelated processes of cargo transportation on the main road transport network. The problem of distribution of available vehicles was stated. The flows of incoming orders are stochastic, but have no features of the simplest. On the specified territory, the orders for long distance transportations appear and are repeated with random periodicity during a fixed period. Each order has its time window. Vehicles of one carrier are placed on a transport network in random order, according to the latest run performed. To execute the orders, motor-vehicle trains take the cargo at the location point, or in the absence of loads, move to the nearest transport point, where such orders appear. The typical situation, when even if there are enough vehicles, clients are denied transportation or vehicles have to stand idle or travel unloaded, was analyzed.</p>The simulation modeling procedure was developed. With the help of the random number generator, the set of coordinates of the points of departure and delivery of random order cargo and the points where vehicles are primarily located, as well as time windows, transportation volumes, and periodicity of orders are obtained. The service is provided according to one of three strategies: without a no-load run and waiting, with a no-load run, with full forecast of the upcoming process. The number of refusals due to the absence of transport or its being engaged was calculated. The parameters for several cycles were calculated. The order handling strategy is implemented based on the correction of decisions of subjects of transportation process at obtaining additional information about previous iterations. The decisions of subjects are limited to the carrier’s intentions. The procedure is applied in order to research the activity of the transport enterprise in the south-eastern territory of Ukraine during the agricultural cargo transportation during the harvest period. The indicators of the incoming flow service were found to have a fluctuating character. Three strategies were compared. The advantages and disadvantages of the application of no-load run, expectations, forecasting, and vehicles distribution by the volume of existing work were identifiedSvitlana SharaiMyroslav OliskevychMaksym Roi2019-10-222019-10-22512 (101)708310.15587/1729-4061.2019.179042Development of composition formulations, based on natural bischofite, to protect wood from fire
http://journals.uran.ua/eejet/article/view/181305
We have studied the chemical composition of natural bischofite extracted from well No. 1 at Zaturin deposit and revealed that the sufficient saturation of МgСl<sub>2</sub> allows its use as an environmentally-oriented base for composition formulations in order to protect wood from fire. Our experimental research has confirmed the efficiency of applying organic synthetic dyes (methyl orange, bromothymol blue) as coloring additives for the reported composition formulations. Technological features have been defined for using the pigment concentrates of trade marks «Amber» and «Sniezko», which form two-phase systems with a solution of natural bischofite. It has been proven that the proposed coloring additives ensure the stable wood coloration and saturated color of its surface. The efficiency of using coloring additives (bromothymol blue and methyl orange; the pigment concentrates of ТМ «Amber» and TM «Sniezko») for the developed composition formulations aimed at fire-protective treatment of wood has been confirmed under laboratory conditions. Our experimental study has established that flammability time of the timber treated with a composition formulation without coloring additives increases by 4 times compared to untreated wood. The fire-retardant mechanism of the developed composition formulations is predetermined by the successive processes of bischofite salt conversion under a temperature influence and by the addition of orthophosphoric acid, which is a strong fire retardant. Introducing the coloring additive (colorant) methyl orange to the composition formulation increases its flammability time by more than 4 times, compared to untreated wood. Thus, there is reason to argue that the developed composition formulations that contain coloring additives (colorants) are environmentally-oriented and economically feasible. At the same time, the results obtained resolve an integrated task, namely ensuring fire- and bio-protection, as well as visualizing the applied treatment of wood-based construction structures at residential buildings and non-residential facilitiesNatalia OmelchenkoViktoriia DmytrenkoNatalia LysenkoAnna BrailkoMaryna Martosenko2019-10-212019-10-21512 (101)314110.15587/1729-4061.2019.181305Studying patterns in the flocculation of sludges from wet gas treatment in metallurgical production
http://journals.uran.ua/eejet/article/view/181300
<p>The influence of a solid phase concentration in the model sludges of wet gas purification, as well as the flocculant consumption, on a change in the solid phase sedimentation rate and the strength of floccules has been examined. This is important because fluctuations in the solid phase concentration in waste water represent an uncontrolled process that significantly affects the kinetics of the solid phase sedimentation and leads to an increase in the flocculant consumption.</p><p>We have proposed a procedure for determining the sedimentation rate of the flocculated sludge and the strength of floccules following the hydromechanical influence, which takes into consideration the solid phase concentration and the flocculant consumption. The study was carried out on model waste water, synthesized by mixing the dust from dry gas purification at actual production site with water. It has been determined that the solid phase concentration affects the rate of floccule deposition. It has been established that the optimum conditions for aggregate formation within a given model system are observed at the solid phase concentration in the interval 8–12 g/l. Increasing the solid phase concentration above 16 g/l decreases the floccule sedimentation rate disproportionately to the flocculant concentration. It is possible to reduce flocculant consumption and to optimize its dosage by carrying out a cleaning process taking into consideration the specified patterns.</p>It was established that the hydromechanical influence on aggregates exerts the destructive effect, whose degree depends on the solid phase concentration. In particular, increasing the rate of fluid motion leads to greater damage to floccules than increasing the time for a less intense exposure. The way to minimize the destructive effect on floccules could be lowering the suspension transportation speed resulting from a decrease in the installation performance or through the increased cross-section of the channel (a pipeline). An increase in the solid phase concentration of the model system above 16 g/l is accompanied by a significant reduction in the strength of floccules. Therefore, when designing wastewater treatment plants that utilize flocculants, it is necessary to provide optimum conditions for aggregation and to minimize the hydromechanical effects on floccules by lowering the velocity of fluid motionOleksii ShestopalovOleksandr BriankinMusii TseitlinValentina RaikoOksana Hetta2019-10-212019-10-21512 (101)61310.15587/1729-4061.2019.181300A study of the effect of deposition conditions on the phase-structural state of ion-plasma WC – TiC coatings
http://journals.uran.ua/eejet/article/view/181291
<p>Studies of the influence of thermal and radiation factors on the elemental composition and phase-structural state of WC-TiC ion-plasma condensates of a quasibinary system are presented. As a thermal factor, we used different substrate temperatures during deposition and temperatures of high-temperature annealing of coatings after their deposition. The influence of the radiation factor was changed by applying a negative bias potential of different magnitudes to the substrate during coating deposition. It was found that with a change in the substrate temperature during deposition (in the temperature range 80–950 °C), a change occurs in the elemental composition of the coating. With an increase in the deposition temperature, the relative content of heavy metal atoms W increases and the relative content of Ti and C atoms decreases. At the phase-structural level, this leads to a change from the single-phase state ((W, Ti)C supersaturated solid solution at a deposition temperature of less than 700 °C) to two-phase ((W, Ti)C and α-W<sub>2</sub>C phases at a deposition temperature of more than 700 °C). The use of high-temperature annealing of coatings after their formation showed a relatively low decay activation efficiency. At an annealing temperature of 800 °C, a noticeable change in the phase-structural state is not observed, and at the highest temperature of 1000 °C and holding for 2 hours, the content of the α-W<sub>2</sub>C phase is relatively small and does not exceed 15 vol %. The supply of a bias potential stimulates the formation of a two-phase state from (W, Ti)C and α-W<sub>2</sub>C phases with nanometer crystallite size. With an increase in the bias potential from –50 V to –115 V, the average crystallite size decreases from 4.5 nm to 3.8 nm.</p>The use of structural engineering methods in the work to create two-phase materials based on a quasibinary WC-TiC system is the basis for increasing the strength and crack resistance of coatings of such systemsOleg Sоbоl`Osman Dur2019-10-212019-10-21512 (101)61310.15587/1729-4061.2019.181291Robust identification of non-stationary objects with nongaussian interference
http://journals.uran.ua/eejet/article/view/181256
<p>The problem of identification of non-stationary parameters of a linear object, which can be described by the first-order Markov model, with non-Gaussian interference is considered. The identification algorithm is a gradient minimization procedure of the combined functional. The combined functional, in turn, consists of quadratic and modular functionals, the weights of which are set using the mixing parameter. Such a combination of functionals makes it possible to obtain estimates with robust properties. The identification algorithm does not require knowledge of the degree of non-stationarity of the investigated object. It is the simplest, since information about only one measurement cycle (step) is used in model construction. The use of the Markov model is quite effective, as it allows obtaining analytical estimates of the properties of the algorithm.</p><p>Conditions of mean and mean-square convergence of the gradient algorithm in the estimation of non-stationary parameters and with non-Gaussian measurement interference are determined.</p>The obtained estimates are quite general and depend both on the degree of object non-stationarity and statistical characteristics of useful signals and interference. In addition, expressions are determined for the asymptotic values of the parameter estimation error and asymptotic accuracy of identification. Since these expressions contain a number of unknown parameters (values of signal and interference dispersion, dispersion characterizing non-stationarity), estimates of these parameters should be used for their practical application. For this purpose, any recurrent procedure for evaluating these unknown parameters should be applied and the resulting estimates should be used to refine the parameters included in the algorithms. In addition, the asymptotic values of the estimation error and identification accuracy depend on the choice of mixing parameterOleg RudenkoOleksandr BezsonovOleh LebedievNataliia Serdiuk2019-10-212019-10-21512 (101)445210.15587/1729-4061.2019.181256Determining the force function distribution in the working zone of a disk magnetic separator
http://journals.uran.ua/eejet/article/view/181043
The paper reports a research into the distribution of magnetic force function in the working zone of a newly-designed disk separator, intended to clean the finely-dispersed bulk substances, transported by a belt conveyor, from unwanted ferromagnetic impurities. It has been shown that it is expedient, in order to create the required magnetic field topology in the working volume of the separator and to improve its energy efficiency, to use permanent magnets. It has been substantiated that the main advantage of the proposed device on permanent magnets is a possibility to self-clean the surface of a non-magnetic rotating discharge disk. Solving the main tasks of this research has employed a finite-element method implemented in the programming environment COMSOL Multiphysics. We have investigated a magnetic force function that acts on multi-domain ferromagnetic particles. Given the complexity of the spatial geometry of power field distribution in the working zone of a disk magnetic separator, we have constructed a three-dimensional model of the magnetic system. The effect of the magnitude of an air gap and, accordingly, the effective length of sector-like permanent magnets on the distribution of power magnetic function in the working zone has been determined. It has been shown that changing the air gap alters both the force function distribution for the height of the working zone and the magnitude of the power action. Recommendations have been given on the use of magnetic systems with different gaps. It has been established that for the extraction of ferromagnetic inclusions the uniformity of the force function distribution in the direction of deploying a spiral of magnets is important. It has been proven that magnetic systems with small gaps should be used in separators without an unloading disk. In this case, the magnetic system can be installed in close proximity to the separated material while the surface of permanent magnets should be carried out manually in proportion to the accumulation of the extracted ferromagnetic inclusions on them. The result of our study is the established rational size for an air interpolar gap, which ensures the maximum magnitude of power action and, consequently, a more efficient operation of the magnetic separatorIryna ShvedchykovaInna MelkonovaHryhorii Melkonov2019-10-182019-10-18512 (101)222910.15587/1729-4061.2019.181043Development of solutions concerning regulation of proper deformations in alkali-activated cements
http://journals.uran.ua/eejet/article/view/181150
<p>The essence of the problem related to proper deformations in alkali-activated cements (AAC) complicated with high content of gel-like hydrate formations was analyzed. Cement types diametrically opposite in their compositions and, accordingly, in the content of gel phases during hydration, that is, the alkali-activated portland cement (AAPC) and alkali-activated slag cement (AASC) were taken for consideration. Approaches to formation of an effective structure of artificial stone counteracting shrinkage deformation by means of interference in structure formation when using complexes of mineral and organic compounds were proposed. Such compounds in composition of complex organo-mineral admixtures jointly influence intensification of crystallization processes and formation of an effective pore structure and morphology of hydrate phases while reducing water content in artificial stone. Salt electrolytes of various anionic types and anion-active surface-active substances were considered as ingredients of the proposed complex modifying admixtures.</p><p>It has been found that the "salt electrolyte–surfactant" system is the most effective for AAPC modification. It was shown that modification of AAPC with this complex admixture based on NaNO<sub>3</sub> reduced shrinkage from 0.406 to 0.017 mm/m. Instead, the use of Na<sub>2</sub>SO<sub>4</sub> provided AAC of this type with a capacity of expansion up to 0.062 mm/m. It was shown that the effect of compensated shrinkage of modified AAPC is associated with a higher crystallization of low-basicity hydrosilicates (CSH(B)) and calcium hydroaluminates (CaO∙Al<sub>2</sub>O<sub>3</sub>∙10H<sub>2</sub>O). An additional effect is associated with formation of sulfate-containing sodium-calcium hydroaluminate (for the Na<sub>2</sub>SO<sub>4</sub>-based system) and crystalline calcium hydronitroaluminate (for the NaNO<sub>3</sub>-based system) with a corresponding microstructure stress.</p>For further development, a complex admixture of "Portland cement clinker–salt electrolyte–surfactant" system was proposed for AASC modification. It provided shrinkage reduction from 0.984 mm/m to 0.683 mm/m. Minimization of the modified AASC shrinkage was explained by formation of sodium hydroalumosilicate of gmelinite type ((Na<sub>2</sub>Ca)∙Al<sub>2</sub>∙Si<sub>4</sub>∙O<sub>12</sub>∙6H<sub>2</sub>O) with a high degree of crystallization along with low-basicity calcium hydrosilicates. It was noted that the cement stone structure is characterized by high density, uniformity, and consolidation of hydrate formationsPavlo KrivenkoVolodymyr GotsOleh PetropavlovskyiIgor RudenkoOleksandr KonstantynovskyiArtem Kovalchuk2019-10-182019-10-18512 (101)243210.15587/1729-4061.2019.181150