Pub Date : 2021-04-01DOI: 10.17516/1997-1397-2021-14-2-215-225
V. Ivanov, N. Erkaev
A mathematical model of non-stationary rotation modes of the rotor of a centrifugal pump is constructed. It is based on preliminary calculation in ANSYS Fluent package with subsequent analytical calculation taking into account the specified parameters
{"title":"Numerical and Analytical Modeling of Centrifugal Pump","authors":"V. Ivanov, N. Erkaev","doi":"10.17516/1997-1397-2021-14-2-215-225","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-2-215-225","url":null,"abstract":"A mathematical model of non-stationary rotation modes of the rotor of a centrifugal pump is constructed. It is based on preliminary calculation in ANSYS Fluent package with subsequent analytical calculation taking into account the specified parameters","PeriodicalId":422202,"journal":{"name":"Journal of Siberian Federal University. Mathematics and Physics","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130699832","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 : 2021-04-01DOI: 10.17516/1997-1397-2021-14-2-186-194
V. Sharifulin, T. Lyubimova
The supercritical modes of water convection are investigated at room temperature in an elongated horizontal cavityes, with a width-to-height ratios of 2 : 1 and 3 : 1. The Prandtl number is assumed to be equal to seven. A constant heat flux is set at the upper free and lower solid boundaries, and the lateral solid boundaries are assumed to be thermally insulated. Calculations carried out by the finite-difference method for values of the Rayleigh number exceeding the critical one by up to thirty times have shown that in the indicated interval of Rayleigh numbers in both cavities in the supercritical region, a single-vortex steady state is realized
{"title":"Supercritical Convection of Water in an Elongated Cavity at a Given Vertical Heat Flux","authors":"V. Sharifulin, T. Lyubimova","doi":"10.17516/1997-1397-2021-14-2-186-194","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-2-186-194","url":null,"abstract":"The supercritical modes of water convection are investigated at room temperature in an elongated horizontal cavityes, with a width-to-height ratios of 2 : 1 and 3 : 1. The Prandtl number is assumed to be equal to seven. A constant heat flux is set at the upper free and lower solid boundaries, and the lateral solid boundaries are assumed to be thermally insulated. Calculations carried out by the finite-difference method for values of the Rayleigh number exceeding the critical one by up to thirty times have shown that in the indicated interval of Rayleigh numbers in both cavities in the supercritical region, a single-vortex steady state is realized","PeriodicalId":422202,"journal":{"name":"Journal of Siberian Federal University. Mathematics and Physics","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131156213","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 : 2021-04-01DOI: 10.17516/1997-1397-2021-14-2-232-243
I. Khamdamov, Z. S. Chay
A convex hull generated by a sample uniformly distributed on the plane is considered in the case when the support of a distribution is a convex polygon. A central limit theorem is proved for the joint distribution of the number of vertices and the area of a convex hull using the Poisson approximation of binomial point processes near the boundary of the support of distribution. Here we apply the results on the joint distribution of the number of vertices and the area of convex hulls generated by the Poisson distribution given in [6]. From the result obtained in the present paper, in particular, follow the results given in [3, 7], when the support is a convex polygon and the convex hull is generated by a homogeneous Poisson point process
{"title":"Joint Distribution of the Number of Vertices and the Area of Convex Hulls Generated by a Uniform Distribution in a Convex Polygon","authors":"I. Khamdamov, Z. S. Chay","doi":"10.17516/1997-1397-2021-14-2-232-243","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-2-232-243","url":null,"abstract":"A convex hull generated by a sample uniformly distributed on the plane is considered in the case when the support of a distribution is a convex polygon. A central limit theorem is proved for the joint distribution of the number of vertices and the area of a convex hull using the Poisson approximation of binomial point processes near the boundary of the support of distribution. Here we apply the results on the joint distribution of the number of vertices and the area of convex hulls generated by the Poisson distribution given in [6]. From the result obtained in the present paper, in particular, follow the results given in [3, 7], when the support is a convex polygon and the convex hull is generated by a homogeneous Poisson point process","PeriodicalId":422202,"journal":{"name":"Journal of Siberian Federal University. Mathematics and Physics","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133740846","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 : 2021-04-01DOI: 10.17516/1997-1397-2021-14-2-161-177
M. Almalahi, S. K. Panchal
In this paper, we derive the representation formula of the solution for ψ-Hilfer fractional differential equation with constant coefficient in the form of Mittag-Leffler function by using Picard’s successive approximation. Moreover, by using some properties of Mittag-Leffler function and fixed point theorems such as Banach and Schaefer, we introduce new results of some qualitative properties of solution such as existence and uniqueness. The generalized Gronwall inequality lemma is used in analyze Eα -Ulam-Hyers stability. Finally, one example to illustrate the obtained results
{"title":"On the Theory of ψ-Hilfer Nonlocal Cauchy Problem","authors":"M. Almalahi, S. K. Panchal","doi":"10.17516/1997-1397-2021-14-2-161-177","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-2-161-177","url":null,"abstract":"In this paper, we derive the representation formula of the solution for ψ-Hilfer fractional differential equation with constant coefficient in the form of Mittag-Leffler function by using Picard’s successive approximation. Moreover, by using some properties of Mittag-Leffler function and fixed point theorems such as Banach and Schaefer, we introduce new results of some qualitative properties of solution such as existence and uniqueness. The generalized Gronwall inequality lemma is used in analyze Eα -Ulam-Hyers stability. Finally, one example to illustrate the obtained results","PeriodicalId":422202,"journal":{"name":"Journal of Siberian Federal University. Mathematics and Physics","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121999796","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 : 2021-04-01DOI: 10.17516/1997-1397-2021-14-2-258-260
V. Rybakov
We find a computational algorithmic task and prove that it is solvable in polynomial time by a non-deterministic Turing machine and cannot be solved in polynomial time by any deterministic Turing machine. The point is that our task does not look as very canonical one and if it may be classified as computational problem in standard terms
{"title":"A Short Essay towards if P not equal NP","authors":"V. Rybakov","doi":"10.17516/1997-1397-2021-14-2-258-260","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-2-258-260","url":null,"abstract":"We find a computational algorithmic task and prove that it is solvable in polynomial time by a non-deterministic Turing machine and cannot be solved in polynomial time by any deterministic Turing machine. The point is that our task does not look as very canonical one and if it may be classified as computational problem in standard terms","PeriodicalId":422202,"journal":{"name":"Journal of Siberian Federal University. Mathematics and Physics","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128245990","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 : 2021-04-01DOI: 10.17516/1997-1397-2021-14-2-152-160
E. L. Ghasab, H. Majani, G. Rad
In this paper, we prove some new fixed point theorems involving set-valued F-contractions in the setting of quasi-ordered metric spaces. Our results are significant since we present Banach contraction principle in a different manner from that which is known in the present literature. Some examples and an application to existence of solution of Volterra-type integral equation are given to support the obtained results
{"title":"Fixed Points of Set-valued F-contraction Operators in Quasi-ordered Metric Spaces with an Application to Integral Equations","authors":"E. L. Ghasab, H. Majani, G. Rad","doi":"10.17516/1997-1397-2021-14-2-152-160","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-2-152-160","url":null,"abstract":"In this paper, we prove some new fixed point theorems involving set-valued F-contractions in the setting of quasi-ordered metric spaces. Our results are significant since we present Banach contraction principle in a different manner from that which is known in the present literature. Some examples and an application to existence of solution of Volterra-type integral equation are given to support the obtained results","PeriodicalId":422202,"journal":{"name":"Journal of Siberian Federal University. Mathematics and Physics","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124661766","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 : 2021-04-01DOI: 10.17516/1997-1397-2021-14-2-178-185
I. Nemtsev, O. Shabanova
The article was prepared based on the materials of the report at the first All-Russian scientific conference with international participation "YENISEI PHOTONICS – 2020". Photonic crystals are structures that have a spatial architecture with a periodically changing complex dielectric function at scales comparable to the wavelengths of light in the visible frequency range. The purpose of this study is to obtain three-dimensional photonic crystals by self-assembly from submicron spherical monodisperse particles of polymethylmethacrylate in dispersion media with different viscosities
{"title":"Manufacturing of Opals from Polymethylmethacrylate Particles in Dispersion Media with Different Viscosities","authors":"I. Nemtsev, O. Shabanova","doi":"10.17516/1997-1397-2021-14-2-178-185","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-2-178-185","url":null,"abstract":"The article was prepared based on the materials of the report at the first All-Russian scientific conference with international participation \"YENISEI PHOTONICS – 2020\". Photonic crystals are structures that have a spatial architecture with a periodically changing complex dielectric function at scales comparable to the wavelengths of light in the visible frequency range. The purpose of this study is to obtain three-dimensional photonic crystals by self-assembly from submicron spherical monodisperse particles of polymethylmethacrylate in dispersion media with different viscosities","PeriodicalId":422202,"journal":{"name":"Journal of Siberian Federal University. Mathematics and Physics","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129595995","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 : 2021-04-01DOI: 10.17516/1997-1397-2021-14-2-251-259
M. A. Goryunova, A. S. Tsipotan, V. Slabko, Мелина А. Горюнова, Алексей С. Ципотан, Виталий В. Слабко
Abstract. In the last decade, ultraviolet detectors have received significant attention due to their widespread use in civil and military fields. In this work, we have studied the effect of radiation of different ranges (UV and visible) on the spectral properties of CdTe quantum dots and wide-gap graphene QDs. The results obtained can be used to create an integrated UV radiation detector based on new physical principles.
{"title":"Photostability of CdTe Quantum Dots and Graphene Quantum Dots under their Continuous Visible and UV Irradiation","authors":"M. A. Goryunova, A. S. Tsipotan, V. Slabko, Мелина А. Горюнова, Алексей С. Ципотан, Виталий В. Слабко","doi":"10.17516/1997-1397-2021-14-2-251-259","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-2-251-259","url":null,"abstract":"Abstract. In the last decade, ultraviolet detectors have received significant attention due to their widespread use in civil and military fields. In this work, we have studied the effect of radiation of different ranges (UV and visible) on the spectral properties of CdTe quantum dots and wide-gap graphene QDs. The results obtained can be used to create an integrated UV radiation detector based on new physical principles.","PeriodicalId":422202,"journal":{"name":"Journal of Siberian Federal University. Mathematics and Physics","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117138924","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 : 2021-04-01DOI: 10.17516/1997-1397-2021-14-2-146-151
S. Alekseev, V. Losev, Y. Grudtsyn, A. Koribut, V. Trofimov
The conditions of broadening the second harmonic spectrum in KDP upon pumping by a negatively chirped pulse of fundamental frequency with central wavelength of 950 nm are analyzed numerically. It is shown that broadening of the spectrum (K = 1.4) is mainly limited by difference in group velocities of radiation pulse between first and second harmonics. The article is based on materials of the report at the first All-Russian scientific conference with international participation "YENISEI PHOTONICS – 2020"
{"title":"Simulation of Broadening the Second Harmonic Spectrum in KDP by Chirp Pulse Pumping","authors":"S. Alekseev, V. Losev, Y. Grudtsyn, A. Koribut, V. Trofimov","doi":"10.17516/1997-1397-2021-14-2-146-151","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-2-146-151","url":null,"abstract":"The conditions of broadening the second harmonic spectrum in KDP upon pumping by a negatively chirped pulse of fundamental frequency with central wavelength of 950 nm are analyzed numerically. It is shown that broadening of the spectrum (K = 1.4) is mainly limited by difference in group velocities of radiation pulse between first and second harmonics. The article is based on materials of the report at the first All-Russian scientific conference with international participation \"YENISEI PHOTONICS – 2020\"","PeriodicalId":422202,"journal":{"name":"Journal of Siberian Federal University. Mathematics and Physics","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122749103","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 : 2021-04-01DOI: 10.17516/1997-1397-2021-14-2-244-250
T. V. Fadeev, M. Dorokhin, I. M. Kuznetsov, L. Kveglis, Vladimir V. Shevchuk
The article shows the ability to control magnetic properties due to modulation of phases in the film with varying temperature of growth. So, at low growth temperatures, a film is formed with an axis of easy magnetization in plane. An increase in temperature leads to a change in the phase composition of the film. It is shown that the presence of even a small component of the magnetization vector in the perpendicular direction leads to the appearance of a thermomagnetic effect of a large magnitude with respect to thermal noise
{"title":"Steel 110G13L. Thermomagnetic and Galvanomagnetic Effects in its Films","authors":"T. V. Fadeev, M. Dorokhin, I. M. Kuznetsov, L. Kveglis, Vladimir V. Shevchuk","doi":"10.17516/1997-1397-2021-14-2-244-250","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-2-244-250","url":null,"abstract":"The article shows the ability to control magnetic properties due to modulation of phases in the film with varying temperature of growth. So, at low growth temperatures, a film is formed with an axis of easy magnetization in plane. An increase in temperature leads to a change in the phase composition of the film. It is shown that the presence of even a small component of the magnetization vector in the perpendicular direction leads to the appearance of a thermomagnetic effect of a large magnitude with respect to thermal noise","PeriodicalId":422202,"journal":{"name":"Journal of Siberian Federal University. Mathematics and Physics","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121305525","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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