Andrii Safonyk
@nuwm.edu.ua
Department of Automation, Electrical and Computer-Integrated Technologies
The National University of Water and Environmental Engineering
RESEARCH INTERESTS
Mathematical Modelling
Scopus Publications
Scopus Publications
Andrii Safonyk, Oleg Rogov, Maksym Trokhymchuk, Olena Prysiazhniuk, and Ihor Prysiazhniuk
Polish Academy of Sciences Chancellery
The main purpose of the article is to develop a multifactorial model for rapid assessment of the efficiency of biological wastewater treatment reactors. A mathematical model of the process of biological wastewater treatment has been developed based on: changes in the concentration of organic contaminants in the bioreactor over time, taking into account the uneven flow of wastewater to the treatment plant, the process of substrate entering the bioreactor (different amounts may enter at different times). The software implementation of the proposed algorithm for solving the corresponding model problem in Python is carried out. The results of computer experiments on the study of the efficiency of wastewater treatment in biological treatment reactors for different operating conditions of facilities are presented. In particular, such processes were considered with taking into account the unevenness of the load, because the maximum cleaning loads are in the morning and in the evening. The task was solved to simulate a real situation and show how cleaning takes place at the maximum load at a certain time of the day. The results obtained will be useful for calculations in the design of biological treatment facilities or in the reconstruction of existing bioreactors for their prospective operation under new operating conditions.
Andrii Safonyk and Myroslav Matviichuk
Springer International Publishing
Ihor Ilkiv, Viktor Zhukovskyy, Nataliia Zhukovska, and Andrii Safonyk
Private Company Technology Center
Methods of mathematical modeling and computer simulation were used to investigate the influence of interrelated processes of transfer of saline solutions in the unsaturated soil layer. To this end, a mathematical model has been built for modeling the corresponding processes of the moisture-, heat-, and mass transfer of saline solutions in an unsaturated soil layer. An effective computational algorithm was developed to solve the corresponding nonlinear boundary problem numerically by the method of finite differences; it was implemented in the Asp.net programming environment in the C++ language. Based on the numerical experiments carried out, the distribution of moisture, concentration, and temperature fields in the aeration zone (incomplete saturation) was obtained. To study the influence of mass transfer of salts on moisture transfer, a numerical solution was found to the problem of moisture transfer, the problem of moisture transfer taking into consideration mass transfer and moisture transfer, taking into consideration mass transfer in the presence of osmosis. Analysis of the results showed that the distribution of the concentration of saline solutions over time is slower and more predictable. It was established that the distribution of moisture heads increases with depth and time when saline solutions fall on the surface of the soil massif. With the influence of salt concentration, the distribution of moisture increases with depth and time throughout the entire area of moisture transfer by 1–3 %. The distribution of moisture heads taking into consideration the concentration of salts and osmosis is reduced by 3–5 % compared to the results of the problem without taking into consideration the phenomenon of osmosis. The distribution of the concentration of saline solutions during moisture transfer and osmosis acquires higher values compared to the results without taking osmosis into consideration. The established features can be successfully applied to clean the fertile soil layer and resume agricultural activities
A Safonyk, I Tarhonii, A Burduk, and A Batako
IOP Publishing
Abstract This paper present the development a model for obtaining a coagulant for the process of cleaning and discoloration of industrial waste water and the development of a PID automated system for wastewater treatment. The description of the processes taking place in an electro-coagulator is given along with the solution obtained by model. The influence of current on the concentration of divalent iron water temperature is investigated. The algorithm of two-circuit regulation of concentration of pollution in sewage with the feedback current between the coagulator plates and the concentration pollutants in the water entering the automated purification system is developed. The automated control system for wastewater treatment process with the implementation of the coagulant forecasting algorithm in relation to the input pollution concentration is developed. The control of current magnitude in the electro-coagulator with minimal electricity consumption was realized. It is planned to manage the system with the ability to change the performance of the entire installation in real time using the SCADA - system.
Kamil Musiał, Artem Balashov, Anna Burduk, Andre Batako, and Andrii Safonyk
Springer International Publishing
Andrii Safonyk, Maksym Mishchanchuk, and Ivanna Hrytsiuk
Springer International Publishing
Andrii Safonyk, Olena Prysiazhniuk, and Ivan Targoniy
IEEE
The process of treatment of industrial water by the magnetic method has been considered in the work. An installation for complex iron removal that allows using a number of parameters to control the process has been developed. The structural scheme of relationships of parameters of the process has been received on the basis of the conducted researches, and further, it has been described by dependence. A conducted computer experiment showed that the process of iron removal from industrial water is not significantly affected by the flow velocity of the fluid.
Viktor Zhukovskyy, Dmytro Dmitriev, Nataliia Zhukovska, Andriy Safonyk, and Andrij Sydor
IEEE
The paper considers the process of compilers designing and highlight parallelism in algorithmic structures. The advantages of existing solutions in the hardware and software areas are highlighted and a new approach for creating a software and hardware compiler is designed. The requirements for our language and the peculiarities of the functioning of each component of the compiler were clearly defined. The basis of the alphabet consists of Latin upper and lower case characters, numbers and delimiters. A description of the lexical analyzer, which highlights tokens and keywords in the text of the input program is provided. Syntactic rules of language (structure of constructions) in the form of diagrams of the Bekus-Naur form and semantic requirements concerning identifiers, length of names of identifiers and labels, arithmetic operations and input/output ports are described as well. The processor compiler with natural parallel execution of instructions was developed. Performance testing and comparative analysis of the efficiency of the developed compiler has shown the advantages of the created solution.
A. Safonyk and I. Ilkiv
Academic Publications
: A spatial mathematical model of biological wastewater treatment depending on the system temperature is presented. The model investigates the relationship between the characteristics of the processes occurring at the treatment plant and offers an algorithm to solve the relevant feature of the perturbation problem and describes the process itself. The graphical relationships and dependencies between the process parameters obtained in the process of work are effective for further theoretical research aimed at optimizing the parameters of the cleaning process, namely: loading time, filter size, etc. In the process of filtration, the shape of the filter plays a significant role because it affects the performance by increasing or decreasing the filtration capacity. The influence of external factors on temperature calculations on the basis of heat transfer equations and laws of thermodynamics is investigated. The effect of water temperature and oxygen concentration on the ability to absorb activated sludge was studied. The results of the distribution of the concentration of contaminants and the temperature field during the purification of the liquid are presented. The dependence of bacterial activity on water temperature has been studied, which allows to increase the accuracy of forecasting and to develop the automation of the biological wastewater treatment process.
Andrii Safonyk, Ivanna Hrytsiuk, Ihor Ilkiv, Ivan Tarhonii, and Andrii Rudyk
IEEE
The problem of improving the process water treatment process quality in terms of changing parameters, dynamic modes of operation and disturbance environment by synthesizing and implementing optimal control during system operation based on intelligent identification and forecasting the state of controlled processes with control of major disturbances. A computer model of the electrocoagulation process with control according to the developed PID and P regulation laws has been developed. A comparative analysis of the system's efficiency at dynamically changing input pollution concentration is carried out.
Nataliia Zhukovska, Viktor Zhukovskyy, and Andrii Safonyk
IEEE
The influence of the dependences of the Lamé coefficients on concentration and temperature on the distributions of the displacements along the axes Ox, Oy and Oz was investigated in the article. Numerous mathematical experiments and their analysis were performed.
Andrii Safonyk, Olena Prysiazhniuk, Ihor Prysiazhniuk, and Andre Batako
Elsevier BV
Andriy Semenov, Olena Semenova, Oleksandr Osadchuk, Iaroslav Osadchuk, Serhii Baraban, Andrii Rudyk, Andrii Safonyk, and Oleksandr Voznyak
Springer International Publishing
Andrii Safonyk, Ivan Tarhonii, Andrii Rudyk, and Ivanna Hrytsiuk
Springer International Publishing
Andrii V. Rudyk, Andriy O. Semenov, Natalia Kryvinska, Olena O. Semenova, Volodymyr P. Kvasnikov, and Andrii P. Safonyk
MDPI AG
A problem of estimating the movement and orientation of a mobile robot is examined in this paper. The strapdown inertial navigation systems are often engaged to solve this common obstacle. The most important and critically sensitive component of such positioning approximation system is a gyroscope. Thus, we analyze here the random error components of the gyroscope, such as bias instability and random rate walk, as well as those that cause the presence of white and exponentially correlated (Markov) noise and perform an optimization of these parameters. The MEMS gyroscopes of InvenSense MPU-6050 type for each axis of the gyroscope with a sampling frequency of 70 Hz are investigated, as a result, Allan variance graphs and the values of bias instability coefficient and angle random walk for each axis are determined. It was found that in the output signals of the gyroscopes there is no Markov noise and random rate walk, and the X and Z axes are noisier than the Y axis. In the process of inertial measurement unit (IMU) calibration, the correction coefficients are calculated, which allow partial compensating the influence of destabilizing factors and determining the perpendicularity inaccuracy for sensitivity axes, and the conversion coefficients for each axis, which transform the sensor source codes into the measure unit and bias for each axis. The output signals of the calibrated gyroscope are noisy and offset from zero to all axes, so processing accelerometer and gyroscope data by the alpha-beta filter or Kalman filter is required to reduce noise influence.
Andrii Safonyk, Viktor Zhukovskyy, and Anna Burduk
IEEE
A mathematical model of biological wastewater treatment has been developed. Mathematical model describes the processes occurring at the treatment plant, taking into account the mutual effects of a range of process characteristics. The influence of external factors for temperature calculation based on thermal balance equation and thermodynamics laws is taken into account. The solution of the corresponding problem was found using the Matlab software environment and pdepe function for solving initial-boundary value problems for systems of parabolic and elliptic partial differential equations in one space variable and time. The results of pollution concentration distribution and temperature distribution over the time of liquid purification are presented. The influence of the aqueous medium temperature and the oxygen concentration on the activated sludge absorption capacity is investigated. The dependence of bacteria activity on the water temperature is shown, which makes it possible to predict and automate technological processes of biological wastewater treatment in a more detailed and comprehensive way.
A. Safonyk and V. Garashchenko
Academic Publications
A mathematical model that describes the patterns of magnetic deposition and impurity accumulation in a porous filter load with taking into account the inverse effects of process characteristics (sediment concentration) on the filtration parameters was developed. We proposed an algorithm for solving the corresponding nonlinear perturbed problem for determining the concentration distribution of impurities and sediment, as well as the time of the protective action of the filter loading τz, variable parameter gradP (x, t), in particular, the limit of pressure loss ∆P . The results of the calculations of the distribution of impurity concentration and mass volume of impurities by the height of the porous filtering loading for different time points, the magnitudes of the filter coefficient at different values of the loading length L, which corresponds to the time of the protective action of loading (filter cycle) are given. This model provides the possibility of automated control of the process of effective deposition of impurities in the magnetized filtering load, depending on the source data of the purified water environment. AMS Subject Classification: 65E05, 65M25, 65M32, 68U20, 65C20
Andrii Safonyk, Olena Prysiazhniuk, and Ihor Prysiazhniuk
IEEE
Mathematical model of heat and mass transfer that couples the heat flow field in the tube with the heat exchange in the surrounding soil was established in this study. It has important applications for the solution of design problems of modern heating systems using renewable energy sources. A mathematical model of the two-dimensional unsteady convection-diffusion process of heat in a heat exchanger tube soil, under conditions of the prevalence of convective its components over diffusive ones has been developed. This let us get the temperature distribution of the coolant along the heat exchanger tubes and within the tube.
Viktor Zhukovskyy, Natalya Zhukovska, Anatolyy Vlasyuk, and Andriy Safonyk
IEEE
In this paper, a new method of usage forensics memory analysis for compromising the carrier-lock algorithm was proposed. The firmware of one popular 3G modem for security issues is investigated. A binary file is reverse engineered using IDA Pro Disassembler and the carrier-lock code algorithm is found. The reproduction of arithmetic and bitwise ARM commands under the IMEI to obtain the unlock code by way of just reverse engineering become impossible because of the algorithm complexity. Therefore the existed ARM code was used to generate the unlock codes on the fly via memory forensics technique and JTAG debugger. A new method was successfully tested on a set of different modem versions.
Andrii Safonyk and Olena Prysiazhniuk
Hindawi Limited
The paper suggests an approach to modeling the electrocoagulation process that is based on the generalization of the equations of incompressible fluid flow in nonisothermal conditions. In the model was taking into account the ratio between the values of the parameters which characterize the domination of convective and mass-exchange components of the process over diffusion. An asymptotic approximation of solutions of corresponding boundary value problems is constructed. Based on the received solutions, we conducted a computer simulation of the process of distribution of iron concentration inside the reactor that allows predicting various hydrodynamic phenomena such as internal recirculation and dead zones that affect the formation of a coagulant. The influence of current strength on the concentration of the target component at the exit from the reactor was investigated using the developed mathematical model. In addition, our findings also show the effect of the rate of heat formation from the electrodes on the efficiency of obtaining of coagulant.