{"title":"Molecular-dynamic Investigation of Silicon Carbide Fracture Under External Mechanical Loads","authors":"A. Utkin, V. Fomin","doi":"10.17516/1997-1397-2021-14-6-787-794","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-6-787-794","url":null,"abstract":"In this study, molecular dynamic simulations of quasi-static compression of silicon carbide nanorod, were performed. A longitudinal through defect in the form of a cylindrical channel was in- troduced into the central part of the nanorod. The influence of the cross sectional size of this internal channel on the strength properties was investigated","PeriodicalId":43965,"journal":{"name":"Journal of Siberian Federal University-Mathematics & Physics","volume":"1 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84010444","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}
T. Brusentseva, V. Shikalov, Sergei M. Lavruk, V. Fomin
{"title":"Simulation of Thermoplastic Powder Cold Spraying","authors":"T. Brusentseva, V. Shikalov, Sergei M. Lavruk, V. Fomin","doi":"10.17516/1997-1397-2021-14-6-726-734","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-6-726-734","url":null,"abstract":"The work is devoted to the deposition of composite powder materials by cold spray method. As a spraying material, a thermoplastic compound «WAY» for marking the roadway was used. An asphalt concrete was used as a substrate. As a result of experimental studies, the dependence of the deposition efficiency on the stagnation temperature of the working air in the ejector nozzle was obtained. The ANSYS Fluent package was used for evaluative modeling of the cold spraying process. Gas flow patterns were obtained in the computational domain without particles and taking into account the interaction of the flow with particles. The trajectory of the particles was calculated for various spraying parameters","PeriodicalId":43965,"journal":{"name":"Journal of Siberian Federal University-Mathematics & Physics","volume":"12 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74239446","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}
{"title":"Modeling of Surface Fracture in Friction Interaction of Fiber Composites","authors":"I. Goryacheva, A. Meshcheryakova","doi":"10.17516/1997-1397-2021-14-6-690-699","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-6-690-699","url":null,"abstract":"The model of the frictional interaction of a fiber composite material with a rigid non- wearing body is proposed, which makes it possible to study the effect of the mechanical and strength characteristics of the fiber and matrix materials and the composite structure on its stress state, in particular, at the fiber-matrix interface. Analysis of the stress distribution in the subsurface layers of the composite was carried out for different values of the ratio of matrix to fiber materials hardness, the sliding friction coefficient and the distance between the fibers. For the known failure criteria of fiber composites, the conclusions about the effect of the structure and relative strength properties of a fiber (fiber bundle) and matrix on the pattern of subsurface fracture of the composite under sliding friction conditions are made","PeriodicalId":43965,"journal":{"name":"Journal of Siberian Federal University-Mathematics & Physics","volume":"31 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85344199","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}
{"title":"Multimode Pulsations In The Axisymmetric Cavern At Supersonic Flow","authors":"D. Gubanov, V. Zapryagaev","doi":"10.25205/2541-9447-2017-12-2-119-128","DOIUrl":"https://doi.org/10.25205/2541-9447-2017-12-2-119-128","url":null,"abstract":"Experimental study results of flow structure and pressure pulsation spectral characteristics of axisymmetric cavern at supersonic flow with Mach number 2 is presented. Multimode pulsation existence is observed. Different modes dominate in different time moments. Maximum of one mode amplitude correspond to minimum value of another. Mode tuning nature is incidental. Time of one mode existence is much more than one of mode oscillation period. It is determine that pulsation mode exist in the form of toroidal and helical disturbances. Numerical calculation results qualitative reproduce multimode fluctuation and corresponded to experimental data","PeriodicalId":43965,"journal":{"name":"Journal of Siberian Federal University-Mathematics & Physics","volume":"134 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83749182","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}
{"title":"Satisfiability in Boolean Logic (SAT problem) is polynomial?","authors":"V. Rybakov","doi":"10.17516/1997-1397-2021-14-5-667-671","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-5-667-671","url":null,"abstract":"We find a polynomial algorithm to solve SAT problem in Boolean Logic","PeriodicalId":43965,"journal":{"name":"Journal of Siberian Federal University-Mathematics & Physics","volume":"1 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88784196","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}
{"title":"Energy Method for the Elliptic Boundary Value Problems with Asymmetric Operators in a Spherical Layer","authors":"V. Denisenko, S. Nesterov","doi":"10.17516/1997-1397-2021-14-5-554-565","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-5-554-565","url":null,"abstract":"Three-dimensional elliptic boundary value problems arising in the mathematical modeling of quasi-stationary electric fields and currents in conductors with gyrotropic conductivity tensor in domains homeomorphic to the spherical layer are considered. The same problems are mathematical models of thermal conductivity or diffusion in moving or gyrotropic media. The operators of the problems in the traditional formulation are non-symmetric. New statements of the problems with symmetric positive definite operators are proposed. For the four boundary value problems the quadratic energy functionals, to the minimization of which the solutions of these problems are reduced, are constructed. Estimates of the obtained quadratic forms are made in comparison with the form appearing in the Dirichlet principle for the Poisson equation","PeriodicalId":43965,"journal":{"name":"Journal of Siberian Federal University-Mathematics & Physics","volume":"1 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83110526","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}
{"title":"On Estimation of the Convergence Rate to Invariant Measures in Markov Branching Processes with Possibly Infinite Variance and Allowing Immigration","authors":"A. Imomov","doi":"10.17516/1997-1397-2021-14-5-573-583","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-5-573-583","url":null,"abstract":"The paper discusses the continuous-time Markov Branching Process allowing Immigration. We are considering a critical case for which the second moment of offspring law and the first moment of immigration law are possibly infinite. Assuming that the nonlinear parts of the appropriate generating functions are regularly varying in the sense of Karamata, we prove theorems on convergence of transition functions of the process to invariant measures. We deduce the speed rate of these convergence providing that slowly varying factors are with remainder","PeriodicalId":43965,"journal":{"name":"Journal of Siberian Federal University-Mathematics & Physics","volume":"72 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84164200","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}
{"title":"A List of Integral Representations for the Diagonal of Power Series of a Rational Function","authors":"Artem V. Senashov","doi":"10.17516/1997-1397-2021-14-5-624-631","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-5-624-631","url":null,"abstract":"In this paper we present integral representations for the diagonals of power series. Such representations are obtained by lowering the multiplicity of integration for the previously known integral representation. The procedure for reducing the order of integration is carried out in the framework of the Leray theory of multidimensional residues. The concept of the amoeba of a complex analytic hypersurface plays a special role in the construction of new integral representations","PeriodicalId":43965,"journal":{"name":"Journal of Siberian Federal University-Mathematics & Physics","volume":"10 2 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82148427","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}
{"title":"On Pairs of Additive Subgroups Associated with Intermediate Subgroups of Groups of Lie Type over Nonperfect Fields","authors":"Ya. N. Nuzhin","doi":"10.17516/1997-1397-2021-14-5-604-610","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-5-604-610","url":null,"abstract":"The author has previously (Trudy IMM UrO RAN, 19(2013), no. 3) described the groups lying between twisted Chevalley groups G(K) and G(F) of type 2Al, 2Dl, 2E6, 3D4 in the case when the larger field F is an algebraic extension of the smaller nonperfect field K of exceptional characteristic for the group G(F) (characteristics 2 and 3 for the type 3D4 and only 2 for other types). It turned out that apart from, perhaps, the type 2Dl, such intermediate subgroups are standard, that is, they are exhausted by the groups G(P)H for some intermediate subfield P, K ⊆ P ⊆ F, and of the diagonal subgroup H normalizing the group G(P). In this note, it is established that intermediate subgroups are also standard for the type 2Dl","PeriodicalId":43965,"journal":{"name":"Journal of Siberian Federal University-Mathematics & Physics","volume":"7 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85431917","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}
D. Fedchenko, V. Stepanenko, R. V. Bikmurzin, Isaeva Victoria V.
{"title":"On Reductants of Two Groups","authors":"D. Fedchenko, V. Stepanenko, R. V. Bikmurzin, Isaeva Victoria V.","doi":"10.17516/1997-1397-2021-14-5-566-572","DOIUrl":"https://doi.org/10.17516/1997-1397-2021-14-5-566-572","url":null,"abstract":"In this paper we consider the reductant of the dihedral group Dn, consisting of a set of axial symmetries, and the sphere S2 as a reductant of the group SU(2,C) ∼= S3 (the group of unit quaternions). By introducing the Sabinin’s multiplication on the reductant of Dn, we get a quasigroup with unit","PeriodicalId":43965,"journal":{"name":"Journal of Siberian Federal University-Mathematics & Physics","volume":"200 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76972143","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}