Pub Date : 2020-01-01DOI: 10.26565/2304-6201-2020-45-06
Statistical relationships between the pressure curves Pa(t), Pd(t) and blood flow velocity Va(t), recorded in vivo in the coronary arteries of patients before and after stenosis, as part of the standard clinical procedure for calculating dynamic indices FFR, HSR, CFR, and a number of other ones generally accepted in surgical practice are studied. It is shown that in the case of insignificant stenosis that does not require surgical intervention, there is a correlation between the curves, and their spectrum is represented by three main harmonics. In the case of significant stenosis requiring immediate stenting, the positive correlation between Pa(t) and Pd(t) is less pronounced, and there is a negative correlation with the Va(t) curve. The spectrum of the curves is much more complex and contains high-frequency harmonics. For patients from the so-called “gray zone”, an expert decision on the need for stenting can be made based on the appearance of additional harmonics in the spectrum and a negative correlation between the Pa(t), Pd(t) and Va(t) curves. The proposed approach can be used for automatic decision-making based on machine learning and the development of appropriate mathematical models.
{"title":"Statistical analysis of coronary blood flow monitoring data for hemodynamic assessment of the degree of coronary artery stenosis","authors":"","doi":"10.26565/2304-6201-2020-45-06","DOIUrl":"https://doi.org/10.26565/2304-6201-2020-45-06","url":null,"abstract":"Statistical relationships between the pressure curves Pa(t), Pd(t) and blood flow velocity Va(t), recorded in vivo in the coronary arteries of patients before and after stenosis, as part of the standard clinical procedure for calculating dynamic indices FFR, HSR, CFR, and a number of other ones generally accepted in surgical practice are studied. It is shown that in the case of insignificant stenosis that does not require surgical intervention, there is a correlation between the curves, and their spectrum is represented by three main harmonics. In the case of significant stenosis requiring immediate stenting, the positive correlation between Pa(t) and Pd(t) is less pronounced, and there is a negative correlation with the Va(t) curve. The spectrum of the curves is much more complex and contains high-frequency harmonics. For patients from the so-called “gray zone”, an expert decision on the need for stenting can be made based on the appearance of additional harmonics in the spectrum and a negative correlation between the Pa(t), Pd(t) and Va(t) curves. The proposed approach can be used for automatic decision-making based on machine learning and the development of appropriate mathematical models.","PeriodicalId":33695,"journal":{"name":"Visnik Kharkivs''kogo natsional''nogo universitetu imeni VN Karazina Seriia Matematichne modeliuvannia informatsiini tekhnologiyi avtomatizovani sistemi upravlinnia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69003300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-01DOI: 10.26565/2304-6201-2020-45-02
This article describes a meshless method for the numerical solution of the seventh-order nonlinear one-dimensional non-stationary Korteweg-de Vries equation. The meshless scheme is based on the use of the collocation method and radial basis functions. In this approach, the solution is approximated by radial basis functions, and the collocation method is used to compute the unknown coefficients. The meshless method uses the following radial basis functions: Gaussian, inverse quadratic, multiquadric, inverse multiquadric and Wu’s compactly supported radial basis function. Time discretization of the nonlinear one-dimensional non-stationary Korteweg-de Vries equation is obtained using the θ-scheme. This meshless method has an advantage over traditional numerical methods, such as the finite difference method and the finite element method, because it doesn’t require constructing an interpolation grid inside the domain of the boundary-value problem. In this meshless scheme the domain of a boundary-value problem is a set of uniformly or arbitrarily distributed nodes to which the basic functions are “tied”. The paper presents the results of the numerical solutions of two benchmark problems which were obtained using this meshless approach. The graphs of the analytical and numerical solutions for benchmark problems were obtained. Accuracy of the method is assessed in terms of the average relative error, the average absolute error, and the maximum error. Numerical experiments demonstrate high accuracy and robustness of the method for solving the seventh-order nonlinear one-dimensional non-stationary Korteweg-de Vries equation.
{"title":"A meshless method for the numerical solution of the seventh-order Korteweg-de Vries equation","authors":"","doi":"10.26565/2304-6201-2020-45-02","DOIUrl":"https://doi.org/10.26565/2304-6201-2020-45-02","url":null,"abstract":"This article describes a meshless method for the numerical solution of the seventh-order nonlinear one-dimensional non-stationary Korteweg-de Vries equation. The meshless scheme is based on the use of the collocation method and radial basis functions. In this approach, the solution is approximated by radial basis functions, and the collocation method is used to compute the unknown coefficients. The meshless method uses the following radial basis functions: Gaussian, inverse quadratic, multiquadric, inverse multiquadric and Wu’s compactly supported radial basis function. Time discretization of the nonlinear one-dimensional non-stationary Korteweg-de Vries equation is obtained using the θ-scheme. This meshless method has an advantage over traditional numerical methods, such as the finite difference method and the finite element method, because it doesn’t require constructing an interpolation grid inside the domain of the boundary-value problem. In this meshless scheme the domain of a boundary-value problem is a set of uniformly or arbitrarily distributed nodes to which the basic functions are “tied”. The paper presents the results of the numerical solutions of two benchmark problems which were obtained using this meshless approach. The graphs of the analytical and numerical solutions for benchmark problems were obtained. Accuracy of the method is assessed in terms of the average relative error, the average absolute error, and the maximum error. Numerical experiments demonstrate high accuracy and robustness of the method for solving the seventh-order nonlinear one-dimensional non-stationary Korteweg-de Vries equation.","PeriodicalId":33695,"journal":{"name":"Visnik Kharkivs''kogo natsional''nogo universitetu imeni VN Karazina Seriia Matematichne modeliuvannia informatsiini tekhnologiyi avtomatizovani sistemi upravlinnia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69003652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-01DOI: 10.26565/2304-6201-2020-46-08
Basic approaches to creating hardware and software for radiation monitoring information systems have been developed in the article. A modern information system for radiation monitoring and control that requires a comprehensive approach and an iterative process of its creation has been developed. The proposed approach to integrating local measuring devices with cloud services, using M2M/IoT technology for remote measurements, advanced semiconductor sensors based on CdTe and CdZnTe radiation detectors, modern microcontroller and communication microchips is highly promising. Developed hardware and software solutions demonstrate increased accuracy due to hardware and software correction of measurement results. A variant of the architectural solution for building a platform for remote access to dosimetric and radiometric measurements is being developed. The solution lies in the direction of improving the parameters of detectors, as well as the characteristics of electronic modules of detecting systems and creating software for controlling the detection process, collecting and digital processing of information, and its adequate presentation to users online. The architecture and structural diagram of a dosimetric system, a sequence diagram, a diagram of a dosimetric system with a subsystem for data exchange over the Internet have been created. A new algorithm for measuring the exposure dose rate of ionizing radiation has been proposed. The block diagram of a microcontroller dosimeter has been developed. The algorithm for correcting the dependence of the sensitivity of the detector based on CdZnTe on the energy of the detected gamma quanta has already been proposed. The algorithm significantly reduces the uncertainty of measuring the radiation dose rate. The architecture and block diagram of the dosimetric system with the possibility of remote access and remote control of the main functions has been presented as well. The calculation of the exposure dose of gamma radiation and the power of the exposure dose with the energy dependence correction have been used. The system elements have proved to be useful for students’ distant laboratory work during the quarantine.
{"title":"Development of basic approaches to creating hardware and software for radiation monitoring information systems","authors":"","doi":"10.26565/2304-6201-2020-46-08","DOIUrl":"https://doi.org/10.26565/2304-6201-2020-46-08","url":null,"abstract":"Basic approaches to creating hardware and software for radiation monitoring information systems have been developed in the article. A modern information system for radiation monitoring and control that requires a comprehensive approach and an iterative process of its creation has been developed. The proposed approach to integrating local measuring devices with cloud services, using M2M/IoT technology for remote measurements, advanced semiconductor sensors based on CdTe and CdZnTe radiation detectors, modern microcontroller and communication microchips is highly promising. Developed hardware and software solutions demonstrate increased accuracy due to hardware and software correction of measurement results. A variant of the architectural solution for building a platform for remote access to dosimetric and radiometric measurements is being developed. The solution lies in the direction of improving the parameters of detectors, as well as the characteristics of electronic modules of detecting systems and creating software for controlling the detection process, collecting and digital processing of information, and its adequate presentation to users online. The architecture and structural diagram of a dosimetric system, a sequence diagram, a diagram of a dosimetric system with a subsystem for data exchange over the Internet have been created. A new algorithm for measuring the exposure dose rate of ionizing radiation has been proposed. The block diagram of a microcontroller dosimeter has been developed. The algorithm for correcting the dependence of the sensitivity of the detector based on CdZnTe on the energy of the detected gamma quanta has already been proposed. The algorithm significantly reduces the uncertainty of measuring the radiation dose rate. The architecture and block diagram of the dosimetric system with the possibility of remote access and remote control of the main functions has been presented as well. The calculation of the exposure dose of gamma radiation and the power of the exposure dose with the energy dependence correction have been used. The system elements have proved to be useful for students’ distant laboratory work during the quarantine.","PeriodicalId":33695,"journal":{"name":"Visnik Kharkivs''kogo natsional''nogo universitetu imeni VN Karazina Seriia Matematichne modeliuvannia informatsiini tekhnologiyi avtomatizovani sistemi upravlinnia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69003774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-01DOI: 10.26565/2304-6201-2020-46-01
The paper presents a model of computational workflows based on end-user understanding and provides an overview of various computational architectures, such as computing cluster, Grid, Cloud Computing, and SOA, for building workflows in a distributed environment. A comparative analysis of the capabilities of the architectures for the implementation of computational workflows have been shown that the workflows should be implemented based on SOA, since it meets all the requirements for the basic infrastructure and provides a high degree of compute nodes distribution, as well as their migration and integration with other systems in a heterogeneous environment. The Cloud Computing architecture using may be efficient when building a basic information infrastructure for the organization of distributed high-performance computing, since it supports the general and coordinated usage of dynamically allocated distributed resources, allows in geographically dispersed data centers to create and virtualize high-performance computing systems that are able to independently support the necessary QoS level and, if necessary, to use the Software as a Service (SaaS) model for end-users. The advantages of the Cloud Computing architecture do not allow the end user to realize business processes design automatically, designing them "on the fly". At the same time, there is the obvious need to create semantically oriented computing workflows based on a service-oriented architecture using a microservices approach, ontologies and metadata structures, which will allow to create workflows “on the fly” in accordance with the current request requirements.
{"title":"The architectures analyzing for computational workflows designing in a distributed environment","authors":"","doi":"10.26565/2304-6201-2020-46-01","DOIUrl":"https://doi.org/10.26565/2304-6201-2020-46-01","url":null,"abstract":"The paper presents a model of computational workflows based on end-user understanding and provides an overview of various computational architectures, such as computing cluster, Grid, Cloud Computing, and SOA, for building workflows in a distributed environment. A comparative analysis of the capabilities of the architectures for the implementation of computational workflows have been shown that the workflows should be implemented based on SOA, since it meets all the requirements for the basic infrastructure and provides a high degree of compute nodes distribution, as well as their migration and integration with other systems in a heterogeneous environment. The Cloud Computing architecture using may be efficient when building a basic information infrastructure for the organization of distributed high-performance computing, since it supports the general and coordinated usage of dynamically allocated distributed resources, allows in geographically dispersed data centers to create and virtualize high-performance computing systems that are able to independently support the necessary QoS level and, if necessary, to use the Software as a Service (SaaS) model for end-users. The advantages of the Cloud Computing architecture do not allow the end user to realize business processes design automatically, designing them \"on the fly\". At the same time, there is the obvious need to create semantically oriented computing workflows based on a service-oriented architecture using a microservices approach, ontologies and metadata structures, which will allow to create workflows “on the fly” in accordance with the current request requirements.","PeriodicalId":33695,"journal":{"name":"Visnik Kharkivs''kogo natsional''nogo universitetu imeni VN Karazina Seriia Matematichne modeliuvannia informatsiini tekhnologiyi avtomatizovani sistemi upravlinnia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69003899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-01DOI: 10.26565/2304-6201-2020-45-01
The aim of the study is elaboration of efficient mathematical models for early diagnostics of the cardiovascular diseases based on the blood flow rate Q(t) curves measured noninvasively in different parts of human body. Ultrasound, rheography, magnetic resonance imaging techniques could be useful for the purpose. In this paper a set of rheographic curves Q(t) has been measured in the abdominal aorta Qc(t), left and right upper Q1(t) and Q2(t) and lower Q3(t) and Q4(t) extremities of 36 volunteers of the age 36-65. Correlation analysis has been used for each pair {Qi(t),Qj(t)} of the measured discrete signals and some statistical indexes have been found significant for reliable early diagnostics of blood insufficiency due to arterial narrowing, improper control and age-related degenerative changes in the blood vessel walls. It is shown that in most individuals the digital curves Q1(t) and Q2(t) well correspond to a linear correlation with a small dispersion, while the curves Q3(t) and Q4(t) are usually weakly correlated, characterized by some time shift between them, significant dispersion and in some patients have unpredictable (chaotic) dynamics. Covariance indices for all the pairs {Qi(t),Qj(t)} of the curves, their spectra and the Lyapunov exponents are calculated. It is shown that in young healthy subjects all the covariances , the spectrum has 3-4 fundamental harmonics, and all Lyapunov exponents <0 that corresponds to regular or quasi-regular dynamics. In most elderly subjects the covariances , especially in the curves measured in the lower extremities, the spectra are complicated, and have positive Lyapunov exponents > 0, that corresponds to the possibility of chaotic dynamics. In the young healthy individuals without diseases and age-related degenerative changes of the cardiovascular system, there are some complications of the spectrum, the presence of both <0 and > 0. Thus, the values , and spectrum of the curves can be important parameters for early diagnosis of age-related changes and circulatory disorders. Their prompt computations can be easily done on any type of cheap and noninvasive ultrasound or impedance rheography curves. Regular measurements and accumulation of such curves in a personal database will increase the quality of individual and population healthcare.
{"title":"Promising mathematical methods for early diagnosis of human circulatory disorders","authors":"","doi":"10.26565/2304-6201-2020-45-01","DOIUrl":"https://doi.org/10.26565/2304-6201-2020-45-01","url":null,"abstract":"The aim of the study is elaboration of efficient mathematical models for early diagnostics of the cardiovascular diseases based on the blood flow rate Q(t) curves measured noninvasively in different parts of human body. Ultrasound, rheography, magnetic resonance imaging techniques could be useful for the purpose. In this paper a set of rheographic curves Q(t) has been measured in the abdominal aorta Qc(t), left and right upper Q1(t) and Q2(t) and lower Q3(t) and Q4(t) extremities of 36 volunteers of the age 36-65. Correlation analysis has been used for each pair {Qi(t),Qj(t)} of the measured discrete signals and some statistical indexes have been found significant for reliable early diagnostics of blood insufficiency due to arterial narrowing, improper control and age-related degenerative changes in the blood vessel walls. It is shown that in most individuals the digital curves Q1(t) and Q2(t) well correspond to a linear correlation with a small dispersion, while the curves Q3(t) and Q4(t) are usually weakly correlated, characterized by some time shift between them, significant dispersion and in some patients have unpredictable (chaotic) dynamics. Covariance indices for all the pairs {Qi(t),Qj(t)} of the curves, their spectra and the Lyapunov exponents are calculated. It is shown that in young healthy subjects all the covariances , the spectrum has 3-4 fundamental harmonics, and all Lyapunov exponents <0 that corresponds to regular or quasi-regular dynamics. In most elderly subjects the covariances , especially in the curves measured in the lower extremities, the spectra are complicated, and have positive Lyapunov exponents > 0, that corresponds to the possibility of chaotic dynamics. In the young healthy individuals without diseases and age-related degenerative changes of the cardiovascular system, there are some complications of the spectrum, the presence of both <0 and > 0. Thus, the values , and spectrum of the curves can be important parameters for early diagnosis of age-related changes and circulatory disorders. Their prompt computations can be easily done on any type of cheap and noninvasive ultrasound or impedance rheography curves. Regular measurements and accumulation of such curves in a personal database will increase the quality of individual and population healthcare.","PeriodicalId":33695,"journal":{"name":"Visnik Kharkivs''kogo natsional''nogo universitetu imeni VN Karazina Seriia Matematichne modeliuvannia informatsiini tekhnologiyi avtomatizovani sistemi upravlinnia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69003599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-01DOI: 10.26565/2304-6201-2020-45-05
O. Demyanchenko, E. Kobilskaya, V. Lyashenko, T. Nabok
This paper presents an mathematical model for the prediction of temperature field distribution in spoke-type permanent magnet synchronous machines. The mathematical model takes into account radial heat transfer streams; it is presented as a boundary problem in a multilayer non-canonical region with conjugation conditions at the boundaries of the layers, with different thermal physical properties. The entire study area is divided into five types of simple subdomains, including a shaft, an inner fan-shaped magnet, an outer fan-shaped magnet, a slot opening and a slot. Moreover, on the border of the inner and outer fan-shaped magnets in slot opening and a slot, we have an perfect thermal contact. The problem is solved by the finite element method. Using the results of numerical experiments, the model allows you to control the temperature field of the machine, allows you to calculate the temperature distribution in its individual parts.
{"title":"The mathematical model of the thermal process in Spoke-Type Permanent Magnet Synchronous Machines","authors":"O. Demyanchenko, E. Kobilskaya, V. Lyashenko, T. Nabok","doi":"10.26565/2304-6201-2020-45-05","DOIUrl":"https://doi.org/10.26565/2304-6201-2020-45-05","url":null,"abstract":"This paper presents an mathematical model for the prediction of temperature field distribution in spoke-type permanent magnet synchronous machines. The mathematical model takes into account radial heat transfer streams; it is presented as a boundary problem in a multilayer non-canonical region with conjugation conditions at the boundaries of the layers, with different thermal physical properties. The entire study area is divided into five types of simple subdomains, including a shaft, an inner fan-shaped magnet, an outer fan-shaped magnet, a slot opening and a slot. Moreover, on the border of the inner and outer fan-shaped magnets in slot opening and a slot, we have an perfect thermal contact. The problem is solved by the finite element method. Using the results of numerical experiments, the model allows you to control the temperature field of the machine, allows you to calculate the temperature distribution in its individual parts.","PeriodicalId":33695,"journal":{"name":"Visnik Kharkivs''kogo natsional''nogo universitetu imeni VN Karazina Seriia Matematichne modeliuvannia informatsiini tekhnologiyi avtomatizovani sistemi upravlinnia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69003260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-01DOI: 10.26565/2304-6201-2020-46-02
The respiratory ducts of animals and humans are presented by curved tubes with complex geometries. The open areas in such structures are filled with moving air governed by a pressure drop between the inlet and outlet of the duct. The complex structures formed by thin walls and warmed by constant blood flow at the body temperatures T=36-39 C serve for fast and efficient warming of the inhaled air to the body temperature and its moistening up to 100% humidity. The Arctic animals possess the most efficient nasal ducts allowing the heating of the inhaled air from T=-30-60C to T=38-39 C during the duct with the length L=8-15 only. The detailed geometry of the nasal ducts of some Arctic animal has been studied on the computed tomograms (CT) scans of the heads of the animals found in the open databases and published in literature. The highly porous structures on some slices are formed by fractal-like divisions of the walls protruded into the nasal lumen. Since the fractal structures are characterized by their fractal dimensions D, the relationships between the hydrodynamic properties and fractal dimensions of the porous structures of the upper respiratory tract of some Arctic animals has been studied. The dimensions D of the cross sections of the tract have been calculated by the counting box method. The porosities of the samples, the tortuosity of the pores, and the equivalent hydraulic diameter Dh of the channel have been calculated. Sierpinski fractals of various types have been used as models of porous structures, for which the above listed parameters, as well as hydraulic resistance to a stationary flow, have also been computed. A number of statistical dependencies between the calculated parameters were revealed, but the absence of their correlations with D was shown. It was obtained, the structures with different porosities and hydraulic resistance Dh can have the same values of D. Therefore, the choice of an adequate model based on only D value introduces significant errors in the calculations of air heating along the upper respiratory tract. The statistical dependences inherent in the natural samples studied can be obtained only on the basis of multifractal models in which the number and shape of the channels, as well as the scale of their decrease, change in a certain way at each generation.
{"title":"Investigation of the relationship between fractal and hydraulic properties of porous structures of the upper respiratory tract of some Arctic animals","authors":"","doi":"10.26565/2304-6201-2020-46-02","DOIUrl":"https://doi.org/10.26565/2304-6201-2020-46-02","url":null,"abstract":"The respiratory ducts of animals and humans are presented by curved tubes with complex geometries. The open areas in such structures are filled with moving air governed by a pressure drop between the inlet and outlet of the duct. The complex structures formed by thin walls and warmed by constant blood flow at the body temperatures T=36-39 C serve for fast and efficient warming of the inhaled air to the body temperature and its moistening up to 100% humidity. The Arctic animals possess the most efficient nasal ducts allowing the heating of the inhaled air from T=-30-60C to T=38-39 C during the duct with the length L=8-15 only. The detailed geometry of the nasal ducts of some Arctic animal has been studied on the computed tomograms (CT) scans of the heads of the animals found in the open databases and published in literature. The highly porous structures on some slices are formed by fractal-like divisions of the walls protruded into the nasal lumen. Since the fractal structures are characterized by their fractal dimensions D, the relationships between the hydrodynamic properties and fractal dimensions of the porous structures of the upper respiratory tract of some Arctic animals has been studied. The dimensions D of the cross sections of the tract have been calculated by the counting box method. The porosities of the samples, the tortuosity of the pores, and the equivalent hydraulic diameter Dh of the channel have been calculated. Sierpinski fractals of various types have been used as models of porous structures, for which the above listed parameters, as well as hydraulic resistance to a stationary flow, have also been computed. A number of statistical dependencies between the calculated parameters were revealed, but the absence of their correlations with D was shown. It was obtained, the structures with different porosities and hydraulic resistance Dh can have the same values of D. Therefore, the choice of an adequate model based on only D value introduces significant errors in the calculations of air heating along the upper respiratory tract. The statistical dependences inherent in the natural samples studied can be obtained only on the basis of multifractal models in which the number and shape of the channels, as well as the scale of their decrease, change in a certain way at each generation.","PeriodicalId":33695,"journal":{"name":"Visnik Kharkivs''kogo natsional''nogo universitetu imeni VN Karazina Seriia Matematichne modeliuvannia informatsiini tekhnologiyi avtomatizovani sistemi upravlinnia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69003969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-01DOI: 10.26565/2304-6201-2020-46-06
Nowadays more and more scientific interest is paid to social processes. It is relatively new, but very important direction because knowledge in this area might have significant impact in many fields of modern life. The purpose of this article is to create a model of public opinion dynamics in modern society. The model is iterative and considers a number of features which are typical for modern society. One of the key components of the model is political parties. They have significant influence on the public opinion. The model takes into account the impact of mass media. It considers both independent and controlled by a political party mass media. Also the model considers influence of social networks, messengers and telephony. In addition, it takes into account geographical position of each state, length of common border between states or social groups and possibly different density of population in each of the states. The model is developed with computer implementation in mind, which significantly simplifies further steps. The author of the article implemented the model in Python programming language with help of tkinter library for user interface and matplotlib for results displaying. Also he gives some implementation advice and performance optimizations. The implemented model has flexible and easy to understand and edit configuration, which makes using of it very convenient. In the last part of the article the built model was tested against several cases which results could be predicted. The first case shows debate of two political parties where first one has notable advantage. The second case shows polarization of the simulated society, where each ideology dominates in a separate region. The last case shows winning of a political party which has significant control over almost all mass media in the simulated society. After simulations of the cases, the model showed results similar to what was expected which indicates that the created in this article model is correct.
{"title":"Model of public opinion dynamics in modern society","authors":"","doi":"10.26565/2304-6201-2020-46-06","DOIUrl":"https://doi.org/10.26565/2304-6201-2020-46-06","url":null,"abstract":"Nowadays more and more scientific interest is paid to social processes. It is relatively new, but very important direction because knowledge in this area might have significant impact in many fields of modern life. The purpose of this article is to create a model of public opinion dynamics in modern society. The model is iterative and considers a number of features which are typical for modern society. One of the key components of the model is political parties. They have significant influence on the public opinion. The model takes into account the impact of mass media. It considers both independent and controlled by a political party mass media. Also the model considers influence of social networks, messengers and telephony. In addition, it takes into account geographical position of each state, length of common border between states or social groups and possibly different density of population in each of the states. The model is developed with computer implementation in mind, which significantly simplifies further steps. The author of the article implemented the model in Python programming language with help of tkinter library for user interface and matplotlib for results displaying. Also he gives some implementation advice and performance optimizations. The implemented model has flexible and easy to understand and edit configuration, which makes using of it very convenient. In the last part of the article the built model was tested against several cases which results could be predicted. The first case shows debate of two political parties where first one has notable advantage. The second case shows polarization of the simulated society, where each ideology dominates in a separate region. The last case shows winning of a political party which has significant control over almost all mass media in the simulated society. After simulations of the cases, the model showed results similar to what was expected which indicates that the created in this article model is correct.","PeriodicalId":33695,"journal":{"name":"Visnik Kharkivs''kogo natsional''nogo universitetu imeni VN Karazina Seriia Matematichne modeliuvannia informatsiini tekhnologiyi avtomatizovani sistemi upravlinnia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69003679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-01DOI: 10.26565/2304-6201-2020-46-04
A lot of methods for solving boundary value problems using arbitrary grids, such as SDI (scattered data interpolation) and SPH (smoothed particle hydrodynamics), use families of atomic radial basis functions that depend on parameters to improve the accuracy of calculations. Functions of this kind are commonly called "shape functions". When polynomials or polynomial splines are used as such functions, they are called "basis functions". The term "radial" means that the carrier of the function is a disk or layer. The term "atomic" means that the support of the function is limited, ie the function is finite. In most cases, the term "finite" is used in English-language publications. The article presents an algorithm for constructing such a function, which is the solution of the functional-differential equation where - circle of radius r: , and . The function generated by this equation has two parameters: r and . Variation of these parameters allows to reduce the error in the calculations of the Poisson boundary value problem by several times. The theorem on the existence of such an unambiguous function is proved in the article. The proof of the theorem allows us to construct one-dimensional Fourier transform of this function in the form , where . Previously, function was calculated using its Taylor approximation (at ), and at – using the asymptotic Hankel approximation of the function . Thus in a circle of a point a fairly large error was found. Therefore, the calculation of the function in the range was carried out by Chebyshev approximation of this function in the range . Chebyshev coefficients (calculated in the Maple 18 system with an accuracy of 26 decimal digits) and the range were chosen by an experiment aimed at minimizing the overall error in calculating of the function . Thanks to the use of the Chebyshev approximation, the obtained function has more than twice less error than calculated by the previous algorithm. Arbitrary value of the function is calculated using a six-point Aitken scheme, which can be considered (to some extent) a smoothing filter. The use of Aitken's six-point scheme introduces an error equal to 6% of the total function calculation error , but helps to save a lot of time in the formation of ARBF in solving boundary value problems using the method of collocation.
{"title":"Some Features of the construction of a family of atomic radial basis functions Plop r,a (x1,x2)","authors":"","doi":"10.26565/2304-6201-2020-46-04","DOIUrl":"https://doi.org/10.26565/2304-6201-2020-46-04","url":null,"abstract":"A lot of methods for solving boundary value problems using arbitrary grids, such as SDI (scattered data interpolation) and SPH (smoothed particle hydrodynamics), use families of atomic radial basis functions that depend on parameters to improve the accuracy of calculations. Functions of this kind are commonly called \"shape functions\". When polynomials or polynomial splines are used as such functions, they are called \"basis functions\". The term \"radial\" means that the carrier of the function is a disk or layer. The term \"atomic\" means that the support of the function is limited, ie the function is finite. In most cases, the term \"finite\" is used in English-language publications. The article presents an algorithm for constructing such a function, which is the solution of the functional-differential equation where - circle of radius r: , and . The function generated by this equation has two parameters: r and . Variation of these parameters allows to reduce the error in the calculations of the Poisson boundary value problem by several times. The theorem on the existence of such an unambiguous function is proved in the article. The proof of the theorem allows us to construct one-dimensional Fourier transform of this function in the form , where . Previously, function was calculated using its Taylor approximation (at ), and at – using the asymptotic Hankel approximation of the function . Thus in a circle of a point a fairly large error was found. Therefore, the calculation of the function in the range was carried out by Chebyshev approximation of this function in the range . Chebyshev coefficients (calculated in the Maple 18 system with an accuracy of 26 decimal digits) and the range were chosen by an experiment aimed at minimizing the overall error in calculating of the function . Thanks to the use of the Chebyshev approximation, the obtained function has more than twice less error than calculated by the previous algorithm. Arbitrary value of the function is calculated using a six-point Aitken scheme, which can be considered (to some extent) a smoothing filter. The use of Aitken's six-point scheme introduces an error equal to 6% of the total function calculation error , but helps to save a lot of time in the formation of ARBF in solving boundary value problems using the method of collocation.","PeriodicalId":33695,"journal":{"name":"Visnik Kharkivs''kogo natsional''nogo universitetu imeni VN Karazina Seriia Matematichne modeliuvannia informatsiini tekhnologiyi avtomatizovani sistemi upravlinnia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69004069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-01DOI: 10.26565/2304-6201-2020-45-03
The article presents an approach to assessing the quality of functioning of scientific institutions based on ontologies. Today, there are a large number of scientific institutions and specialized organizations whose efficiency depends on the quality of the services they provide. In the course of their operation, institutions accumulate a large amount of information (scientific articles, reports, employee ratings, economic indicators, etc.) that can be used to evaluate them automatically by national criteria. This study proposes to use an ontological model to store, present and manipulate with such information. Ontologies are new intelligent tools for finding resources on the Internet, new methods for representing and processing knowledge and queries. They are able to accurately and efficiently describe the semantics of data for a certain domain and solve the problem of incompatibility and inconsistency of concepts. The ontological approach allows the continuous improvement of the model based on basic ontologies by completing and developing them The ontology will allow not only to structure and systematize the data of scientific institutions, but also to perform the procedure of quality assessment through the mechanism of ontological logical inference. A general ontology for describing the activities of scientific institutions is represented by a system of five connected components. In the paper the structure of such a system is described, basic elements of its ontologies and the connections between them are highlighted. The ontology of the scientific institution activity is developed using specific technological platform TEDAOS - “Transdisciplinary Educational Dialogues of Applications’ Ontology Systems”.
{"title":"Ontological model for evaluating the effectiveness of scientific institutions","authors":"","doi":"10.26565/2304-6201-2020-45-03","DOIUrl":"https://doi.org/10.26565/2304-6201-2020-45-03","url":null,"abstract":"The article presents an approach to assessing the quality of functioning of scientific institutions based on ontologies. Today, there are a large number of scientific institutions and specialized organizations whose efficiency depends on the quality of the services they provide. In the course of their operation, institutions accumulate a large amount of information (scientific articles, reports, employee ratings, economic indicators, etc.) that can be used to evaluate them automatically by national criteria. This study proposes to use an ontological model to store, present and manipulate with such information. Ontologies are new intelligent tools for finding resources on the Internet, new methods for representing and processing knowledge and queries. They are able to accurately and efficiently describe the semantics of data for a certain domain and solve the problem of incompatibility and inconsistency of concepts. The ontological approach allows the continuous improvement of the model based on basic ontologies by completing and developing them The ontology will allow not only to structure and systematize the data of scientific institutions, but also to perform the procedure of quality assessment through the mechanism of ontological logical inference. A general ontology for describing the activities of scientific institutions is represented by a system of five connected components. In the paper the structure of such a system is described, basic elements of its ontologies and the connections between them are highlighted. The ontology of the scientific institution activity is developed using specific technological platform TEDAOS - “Transdisciplinary Educational Dialogues of Applications’ Ontology Systems”.","PeriodicalId":33695,"journal":{"name":"Visnik Kharkivs''kogo natsional''nogo universitetu imeni VN Karazina Seriia Matematichne modeliuvannia informatsiini tekhnologiyi avtomatizovani sistemi upravlinnia","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69003191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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