Mathematica Montisnigri最新文献_第5页

Multigrid method for numerical modelling of high temperature superconductors 高温超导体数值模拟的多重网格法

Mathematica Montisnigri Pub Date : 1900-01-01 DOI: 10.20948/mathmontis-2022-53-7

O. Feodoritova, N. Novikova, M. M. Krasnov, V. Zhukov

{"title":"Multigrid method for numerical modelling of high temperature superconductors","authors":"O. Feodoritova, N. Novikova, M. M. Krasnov, V. Zhukov","doi":"10.20948/mathmontis-2022-53-7","DOIUrl":"https://doi.org/10.20948/mathmontis-2022-53-7","url":null,"abstract":"An approach to numerical simulation of three-dimensional electrical and thermal fields in high-temperature superconductors is described. In such a semiconductor, the phenomena of superconductivity are observed at high temperatures above the temperature of liquid nitrogen. The absence of a generally accepted theory of superconductivity leads to the need to study physical processes in semiconductor structures using mathematical simulations. The main attention is paid to the calculation of temperature and electric current distributions in large-size mesas with a self-heating effect. An efficient algorithm for solving the equations describing these distributions is constructed. The basis of the algorithm is an adaptive multigrid method on structured Cartesian grids. The adaptability is based on the Chebyshev iterative method for constructing the smoothing procedures at each grid level and for solving the coarsest grid equations. The adaptive technique allows us to realistically simulate the anisotropic phenomena. The functionality of the algorithm is demonstrated along with an example of solving an anisotropic model problem with discontinuous coefficients.","PeriodicalId":170315,"journal":{"name":"Mathematica Montisnigri","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124537525","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}

引用次数: 0

Modeling of the radiation induced electromagnetic field in finely-disperse media 细分散介质中辐射感应电磁场的模拟

Mathematica Montisnigri Pub Date : 1900-01-01 DOI: 10.20948/mathmontis-2021-52-6

M. Zhukovskiy, V. Egorova

{"title":"Modeling of the radiation induced electromagnetic field in finely-disperse media","authors":"M. Zhukovskiy, V. Egorova","doi":"10.20948/mathmontis-2021-52-6","DOIUrl":"https://doi.org/10.20948/mathmontis-2021-52-6","url":null,"abstract":"Algorithms for supercomputer modeling of the radiation electromagnetic field in heterogeneous materials of a complex finely-dispersed structure are constructed. A geometric model of a heterogeneous medium is created using Stilinger-Lubachevsky algorithms for multimodal structures. The model includes a system of detectors for statistical evaluation of functionals on the space of solutions of the photon-electron cascade transport equations. Algorithms for the three-dimensional approximation of the results of modeling the radiation transport in a fine-dispersed medium to an electrodynamic difference grid are developed. The approximation methods based on the technology of neural networks. The method of numerical solution of the complete system of Maxwell's equations for calculating the electromagnetic field in a fine-dispersed medium is worked out. The results of demonstration calculations of the electromagnetic field are presented. The results of the calculations show that the spatial distribution of the radiation electromagnetic field has a sharply inhomogeneous structure caused by the presence of boundaries of materials with different radiation properties.","PeriodicalId":170315,"journal":{"name":"Mathematica Montisnigri","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131140857","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}

引用次数: 0

Cubic intuitionistic structures of a semigroup in KU-algebra ku -代数中半群的三次直观结构

Mathematica Montisnigri Pub Date : 1900-01-01 DOI: 10.20948/mathmontis-2023-56-7

B. Davvaz, F. F. Kareem, Wisam K. Awad

引用次数: 0

Some aspects of Neyman triangles and Delannoy arrays 内曼三角形和Delannoy数组的一些方面

Mathematica Montisnigri Pub Date : 1900-01-01 DOI: 10.20948/MATHMONTIS-2021-50-4

O. Deveci, A. Shannon

引用次数: 1

Life long scientific feat. On the occasion of centenary of the birth of academician of RAS A.A. Samarskii 终身科学壮举。值此俄罗斯科学院院士萨马斯基诞辰一百周年之际

Mathematica Montisnigri Pub Date : 1900-01-01 DOI: 10.20948/mathmon-2019-44-12

B. Chetverushkin, A. Aptekarev, V. Mazhukin, O. Koroleva, M. Demin, A. Mazhukin

{"title":"Life long scientific feat. On the occasion of centenary of the birth of academician of RAS A.A. Samarskii","authors":"B. Chetverushkin, A. Aptekarev, V. Mazhukin, O. Koroleva, M. Demin, A. Mazhukin","doi":"10.20948/mathmon-2019-44-12","DOIUrl":"https://doi.org/10.20948/mathmon-2019-44-12","url":null,"abstract":"The article is dedicated to the 100th anniversary of the outstanding Soviet and Russian scientist, Academician of the USSR Academy of Sciences and the Russian Academy of Sciences Alexander Andreevich Samarskii, the founder of the Soviet and Russian school of mathematical modeling, the creator of the fundamental general theory of difference schemes, an outstanding teacher who brought up more than one generation of famous scientists , an active organizer and a bright advocate of science. Scientific activities of academician A.A. Samarskii is strongly associated with the Keldysh Institute of Applied Mathematics of Academy of Sciences of the USSR and the Russian Academy of Sciences and the Institute of Mathematical Modeling of the Russian Academy of Sciences, which he headed. A brilliant scientist and an excellent organizer, he laid down the potential to keep the world level of Russian science in the most important area of mathematical modeling for our country. 1. A.A. SAMARSKII THE FOUNDER OF THE NATIONAL SCHOOL OF MATHEMATICAL MODELING Alexander Andreevich Samarskii was born on February 19, 1919 in the village of NovoIvanovskoye, Donetsk-Amvrosievsky District, Donetsk Region, into a peasant family. He began his education at the village school, and then attended the secondary school named after A.P. Chekhov in Taganrog, which in 1936 he graduated with honors. After school, A.A. Samarskii entered the Faculty of Physics of the Lomonosov Moscow State University. In 1939 he began working in the scientific seminar of professor A.N. Tikhonov, a brilliant mathematician, a future academic, world-famous scientist. Since that time, the collaboration of two eminent scientists, which lasted for many decades, began.","PeriodicalId":170315,"journal":{"name":"Mathematica Montisnigri","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127737915","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}

引用次数: 0

Molecular dynamic calculation of lattice thermal conductivity of gold in the melting-crystallization region 熔融结晶区金晶格热导率的分子动力学计算

Mathematica Montisnigri Pub Date : 1900-01-01 DOI: 10.20948/MATHMONTIS-2019-46-9

M. Demin, V. Mazhukin, A. A. Aleksashkina

{"title":"Molecular dynamic calculation of lattice thermal conductivity of gold in the melting-crystallization region","authors":"M. Demin, V. Mazhukin, A. A. Aleksashkina","doi":"10.20948/MATHMONTIS-2019-46-9","DOIUrl":"https://doi.org/10.20948/MATHMONTIS-2019-46-9","url":null,"abstract":"Of all the metals, gold is the most well-known and widely used material in scientific research, industrial production and, more recently, in biomedicine problems. In the temperature range 300 ≤ T ≤ 2000 K, including the region of the melting – crystallization phase transition, the results of modeling the phonon thermal conductivity of gold are presented. Phonon thermal conductivity plays an important role in modeling the mechanisms of interaction of pulsed laser radiation with gold in the framework of the two-temperature continuum model. In the region of the phase transition, overheating-undercooling of the solid phase occurs, the substance changes its structure. These phenomena are associated with changes in the phonon subsystem of gold, therefore, for mathematical modeling of heatingcooling, it is necessary to know the characteristic of heat transfer as the thermal conductivity of the phonon subsystem of gold. Obtaining the temperature dependence of phonon thermal conductivity in such a wide temperature range from experiment is problematic. In this work, phonon thermal conductivity was obtained by the direct non-equilibrium method in the framework of molecular dynamics modeling using the EAM potential.","PeriodicalId":170315,"journal":{"name":"Mathematica Montisnigri","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128130844","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}

引用次数: 6

Automated cryptanalysis of substitution cipher using Hill climbing with well designed heuristic function 具有良好设计的启发式函数的爬山替代密码的自动密码分析

Mathematica Montisnigri Pub Date : 1900-01-01 DOI: 10.20948/MATHMON-2019-44-11

Luka Bulatović, Anđela Mijanović, Balša Asanović, Nikola Trajković, V. Bozovic

引用次数: 0

Modeling limit states for curvilinearly reinforced rotated disks 曲线早期增强旋转盘极限状态建模

Mathematica Montisnigri Pub Date : 1900-01-01 DOI: 10.20948/MATHMON-2019-44-7

Y. Nemirovsky, N. Feodorova

引用次数: 3

On a sum over primitive sequences of finite degree 有限次原始序列的和

Mathematica Montisnigri Pub Date : 1900-01-01 DOI: 10.20948/mathmontis-2022-53-4

Ilias Laib, Nadir Rezzoug