Poltava National Technical Yuri Kondratyuk Research Articles

Vertical differential grout pump experimental studies methods validation

The article is devoted to creation and substantiation of experimental research method of vertical differential grout pumpwith flowing piston mark РН 2-4, developed by researchers at Poltava National Technical Yuri Kondratyuk University.Experiments type has been substantiated, variation intervals of the studied parameters values have been determined, thepreparation of the experimental sample of the grout pump for research has been described, an experimental installation for researchhas been designed, the measuring means have been selected, the conditions for performing the experiments have beendetermined. This technique enables to find the rational values for the following parameters of the solution pump when workingwith plaster solutions of different displacement: working body frequency movement, diameter, mass and height of liftingover the valve, the hole diameter in the valve sockets.

Use of thermal and magnetic devices for prevention of asphaltene, resin, and wax deposits on oil equipment surfaces

The present study would have been impossible without support from Poltava National Technical Yuri Kondratyuk University administration. We express our sincere gratitude to Rector Volodymyr Onyshchenko for the opportunity to conduct tests in modern Laboratory of Oil and Gas Technologies.

ALGORITHM AND SOFTWARE FOR CALCULATING THE STABILITY OF THE FORM OF EQUILIBRIUM OF DISCRETE SYSTEMS

The paper presents an algorithm for calculating the stability of the form of equilibrium of the first kind of compressed discrete systems by the method of displacements in combination with themethods of iterations and bisection. The use of the displacement method in combination with the iteration and bisection methods makes it possible to effectively determine the minimum critical stress or strain at the first bifurcation and their corresponding form of loss of stability, both for statically determined and statically undetectable systems. This approach, using matrixforms, makes it possible to significantly simplify the calculations of the analytical condition for the loss of stability of compressed discrete systems (the stability loss equation), which has high orders, as well as to construct the form of loss of stability corresponding to a critical load, that is, to solve the problem of loss of stability of equilibrium. The calculation of the compressed discrete system on the stability of the form of equilibrium actually reduces to the solution of the difficultly described nonlinear transcendental equation, which is the equation of loss of stability. The difficulty lies in the absence of an analytical solution of such an equation due to the presence of complex functions of Zhukovsky, which have transcendental functions in their structure. Such solution can be performed only with the use of numerical methods. This algorithm for calculating the loss of equilibrium of the first kind of compressed discrete systems by displacement in combination with the methods of iteration and bisection is implemented in the software complex "Persist" for a PC in Windows OS. The program was approbated and implemented in theeducational process at the Department of Structural and Theoretical Mechanics of the Poltava National Technical Yuri Kondratyuk University during the training of specialists in engineering specialties.

Blockchain technology in the workflow system of higher education institutions

The article presents the results of a study of the theoretical foundations of the Blockchain technology. The analysis of the organization structure of its units and the principles of the system. Algorithms of smart contracts are considered and their advantages and disadvantages are analyzed. The purpose of the study is that based on the analysis of the theoretical foundations of building systems using blockchain technology and introducing them into various areas, to propose a system model using smart contracts on the Etherium platform for use in the workflow system in institutions of higher education. Convenient web interfaces for managing the creation of a contract and a module for the interaction of smart contracts with a Web application have been developed.
 The management of an institution of higher education, namely, a department, faculty or institute, involves the correct and timely preparation of various documentation, in which the documentation on student learning outcomes holds a special place. On its basis various financial and reporting documents are being prepared. To this end, institutions of higher education are introducing workflow system and office automation systems to manage the processing of documents, as well as to organize control over the implementation of these processes. The paper proposes the introduction of a blockchain system on the Ethereum platform using smart contracts written in the Solidity language. Solidity is a tool that is used to create machine-level code that can be run on an Ethereum Virtual Machine. Solidity allows you to create and execute a smart contract without requiring centralized or trusted parties. The use of such technologies makes it possible to significantly reduce the number of paper-based information carriers and, to a significant extent, further automate the existing the workflow system in institutions of higher education.
 The proposed system is a part of the workflow system of institutions of higher education, which is designed to automate the process of passing documents related to taking into account and submitting to the dean's office of the faculty or the institute the results of the final controls on academic disciplines or the results of retake of tests and exams. This process requires a large number of documents on paper. The proposed system is deployed in the local computer network of the Educational and Scientific Institute of Information Technologies and Mechatronics of Poltava National Technical Yuri Kondratyuk University and is being tested. The results allow us to draw conclusions about the reduction in the number of paper documents; time to obtain permits. In addition, the level of reliability and protection of information transmitted to the administration of the faculty or institute for further processing has increased. In the future, it is planned to introduce the proposed system for document flow automation for all institutes and faculties of the Poltava National Technical Yuri Kondratyuk University.

Calculation of The Stability of the Form of Equilibrium of Discrete Systems

The paper presents an algorithm for calculating the stability of the equilibrium form of the first kind of compressed discrete systems by the displacements method in combination with the methods of iterations and bisection. The use of the methods makes it possible to effectively determine the minimum critical stress or strain at the first bifurcation and their corresponding form of stability loss, both for statically determined and statically undetermined systems. This approach, using matrix forms, makes it possible to significantly simplify the calculations of the analytical condition for the stability loss of compressed discrete systems (the stability loss equation), which has high orders, as well as to construct the form of stability loss corresponding to a critical load, that is, to solve the problem of loss of equilibrium stability. The calculation actually leads to solving a nonlinear transcendental equation, which is the equation of stability loss. The difficulty lies in the absence of an analytical solution of such an equation due to the presence of complex of Zhukovsky functions, which have transcendental functions in their structure. Such solution can be performed only with the use of numerical methods. This algorithm for calculating the loss of equilibrium of the first kind of compressed discrete systems by displacement in combination with the methods of iteration and bisection is implemented in the software complex "Persist" for PC in Windows OS. The program was approbated and implemented in the educational process at the Department of Structural and Theoretical Mechanics of Poltava National Technical Yuri Kondratyuk University during the training of specialists in engineering specialties.

Experimental Study on the Multikeyed Joints of Concrete and Reinforced Concrete Elements

The connections ensure teamwork under the load of buildings and structures bearing elements. Joints distraction leads to a change in the structures support conditions and their design schemes. Keyed joints are the most effective under significant shear force action because they have high shear resistance. This makes it necessary to further improve their design solutions. In the article the experimental study results of multikeyed joints two series are presented. The joint models were tested in the department laboratory of reinforced concrete and stone structures and resistance of materials Poltava National Technical Yuri Kondratyuk University. The keyed profile (key’s depth to height ratio and load application surface angle), reinforcement (quantity of reinforcement and its location character), seam width, keys number were varied in experiments. Heavy-weight concrete, expanded clay concrete and polypropylene fiber concrete were used for the samples manufacture. In experiments the influence of one of listed factors and their combinations for bearing capacity were studied. The concrete and reinforcement strains, distraction character, the failure load were studied. The influence degree analysis of the factors determining the strength was carried out. The design joints parameters that correspond to maximum strength were determined.

STRENGTH OF HIGHER STRENGTH CONCRETE ELEMENTS UNDER SHEAR ACTION

The strength design method of concrete and reinforced concrete elements is expounded in this article. The experimental program included the study of the strain condition and failure load determination for considered types of elements. The strength design method is expounded for concrete and reinforced concrete elements by means of variation method in the concrete plasticity theory that was developed in Poltava National Technical Yuri Kondratyuk University. There are the results of experimental investigation for truncated concrete wedges that simulate work of concrete compressed zone above dangerous inclined crack, Hvozdev specimens and crucial keys as well as beams. Also all elements were made of higher strength concrete in order to test the applicability of given method to these elements. The results of the experimental research have confirmed the applicability of plasticity zones assumed in the theoretical solutions. The theoretical strength is well coordinated with the experimental one. The failure character of reinforced concrete beams has been discovered. It has not differed from the flexure elements failure by cross section made of conventional concrete.

The improved technique for calculating the concrete elements strength under local compression

The central one-sided concrete element crushing is considered when the loading platform width is less than the element width (in three-dimensional stress state conditions). A variational method in the concrete plasticity theory, which is developed in the Poltava National Technical Yuri Kondratyuk University, is proposed to calculate the strength. The formula for determining the ultimate load is based on the destruction kinematics, which is observed in the experiments, and takes into account the loading platform size ratio and the element, both concrete strength characteristics, the frictional forces between the support surface and the element. The calculation dependence is rather precise during the cubes central crushing when the element height ratio and the loading platform greater than 4. With other geometric parameters the kinematic scheme changes, which must be taken into account when deriving the formulas for calculating the strength by the variational method. The proposed method allows considering all possible calculation schemes and determining its application limits.

Analysis of magnetic treatment of production fluid with high content of asphalt-resin-paraffin deposits

The present study would have been impossible without support from Poltava National Technical Yuri Kondratyuk University administration. We express our sincere gratitude for the opportunity to conduct tests in modern Laboratory of Oil and Gas Technologies.

DYNAMIC MONITORING IN ANTI-CRISIS MANAGEMENT OF STATE ECONOMIC SECURITY

UDC 6585:330
 
 Savenko Ruslan, doctor of sciences, professor. Poltava national technical Yuri Kondratyuk university. Dynamic monitoring in anti-crisis management of state economic security. This paper aimed at the problem of improvement the management system of economic security of natural use objects on a regional level using the organized digital dynamic monitoring for informational provision and justifying the options of efficient management decisions of operative and strategic importance by criteria of ecological, economic and social security.
 Monitoring of the regional (territorial) natural objects provides constant systematic observation of the processes that take place inside of a “region-state” system and at world’s natural resources market. It needed to create the informational database for efficient management of a nature-use system.
 We suggest plan of making the scientific and research institute in PoltNTU for conducting investigations based on continuous informational monitoring.
 Keywords: monitoring, management system, ecological-economic-social security, natural use resources, algorithm, scientific and research institute, management decisions.

GOVERNMENT REGULATION OF LAND RELATIONS: CIRCULATION OF AGRICULTURAL LAND

UDC: 332.2.021.,332.02.
 Shary G., Phd. Associate Professor. Dubіschev V., DSc, Professor. Poltava National Technical Yuri Kondratyuk University. Government regulation of land relations: circulation of agricultural land. The need for institutional development and the basic principels of improving government regulation of circulation of agricultural land in Ukraine under modern conditions is reveals.
 Keywords: the lands’ circulation, government regulation, institution, valuation.

IDENTIFICATION OF STRATEGIC PRIORITIES OF INVESTMENT INTO DEVELOPMENT OF ALTERNATIVE ENERGETICS

UDC 338:336.02:621.311
 Svitlana Sivitska, Ph.D., Associate Professor at Finance and Banking Department, Vice-Rector for Scientific, Educational, Social Work and International Cooperation. Poltava National Technical Yuri Kondratyuk University. Identification of strategic priorities of investment into development of alternative energetics. There are the stages of the methodology for choosing the strategic priorities of investing in alternative energy explored in the article. The potential of alternative energy analyzed. The strategic priorities of alternative energy have been explored. An integrated analysis of the potential of alternative energy is carried out on the territorial basis done. The matrix of choice of strategic priorities of investing in alternative energy determined.
 Keywords: energetic security, alternative energetics, renewable sources of energy, investment, strategic priorities, matrix.