COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)最新文献

{"title":"Calculation of aerodynamic heating and ablation of thermal protection system in axisymmetric formulation","authors":"D. Minyushkin, I. Kryukov","doi":"10.1063/1.5135685","DOIUrl":"https://doi.org/10.1063/1.5135685","url":null,"abstract":"High-speed aircrafts are exposed to severe aerodynamic heating during flight. Strong aerodynamic heating results in ablation of a thermal protection system (TPS). Ablation of the material leads to a change in the shape of the body, which is reflected in the aerodynamic characteristics of the aircraft. It means that the task of TPS material ablation is a conjugate one. The article presents a numerical method for calculating the ablation and heating of thermal protection system on moving grids. Thermal and power loads were calculated by solving the Navier-Stokes equations. The method was validated on experimental data obtained at the NASA Ames research center. In the experiment, the ablation of a POCO graphite sample was studied in an arc-jet facility. A sublimation regime of graphite ablation was achieved.","PeriodicalId":268263,"journal":{"name":"COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123918116","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":"Computational model for satellite periodic motion","authors":"Liudmila Kondratieva","doi":"10.1063/1.5135662","DOIUrl":"https://doi.org/10.1063/1.5135662","url":null,"abstract":"Using the technique of inertial manifolds of ordinary differential equations in ℝn, we establish the existence of stable periodic motion of the satellite with a certain choice of controls. The presence of a two-dimensional inertial manifold allows us to reduce the problem of detecting such motions to the Poincare-Bendixson theory for dynamical systems on the plane. On the basis of the harmonic balance version, we obtain approximate analytical formulas for the corresponding closed trajectories and give accuracy estimates.Using the technique of inertial manifolds of ordinary differential equations in ℝn, we establish the existence of stable periodic motion of the satellite with a certain choice of controls. The presence of a two-dimensional inertial manifold allows us to reduce the problem of detecting such motions to the Poincare-Bendixson theory for dynamical systems on the plane. On the basis of the harmonic balance version, we obtain approximate analytical formulas for the corresponding closed trajectories and give accuracy estimates.","PeriodicalId":268263,"journal":{"name":"COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130052483","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":"Prototype-based programming with fractal algebra","authors":"A. Semenov","doi":"10.1063/1.5135669","DOIUrl":"https://doi.org/10.1063/1.5135669","url":null,"abstract":"The aim of this article is to present the formal simulation model of an elastic distributed system which transformed dynamically at runtime. The model based on fractal algebra and concept software containers. The model has a high level abstraction, operates with container objects, simulates different levels of the system granularity, and makes predictions about behavior of transformation. The model integrates with pprototype-based programming. The example of the elastic system model optimized on demand by strategy planning is given.","PeriodicalId":268263,"journal":{"name":"COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127504401","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":"Study on gas-dynamic effects in nozzles during their oscillating motion","authors":"I. Ivanov, I. Kryukov","doi":"10.1063/1.5135686","DOIUrl":"https://doi.org/10.1063/1.5135686","url":null,"abstract":"A flow of a viscous gas from a nozzle, which oscillates around an axis perpendicular to the axis of symmetry of the nozzle, is considered. The study of the gas-dynamic process is based on the numerical solution of the two-dimensional and three-dimensional Navier-Stokes equations, written in a non-inertial reference frame associated with the nozzle and using the relative components of velocities and accelerations. The flow characteristics in plane and axisymmetric nozzles and jets exhausted from it are obtained using a high order of accuracy method.A flow of a viscous gas from a nozzle, which oscillates around an axis perpendicular to the axis of symmetry of the nozzle, is considered. The study of the gas-dynamic process is based on the numerical solution of the two-dimensional and three-dimensional Navier-Stokes equations, written in a non-inertial reference frame associated with the nozzle and using the relative components of velocities and accelerations. The flow characteristics in plane and axisymmetric nozzles and jets exhausted from it are obtained using a high order of accuracy method.","PeriodicalId":268263,"journal":{"name":"COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134644743","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":"Approximate MMSE and MAP estimation using continuous-time particle filter","authors":"Konstantin Chugai, Ivan M. Kosachev, K. Rybakov","doi":"10.1063/1.5135661","DOIUrl":"https://doi.org/10.1063/1.5135661","url":null,"abstract":"The algorithm is proposed for solving approximately the optimal filtering problem for nonlinear continuous-time stochastic observation systems that provides two estimates for the state. These estimates are the minimum mean squared error estimate and the maximum a posteriori estimate. The proposed algorithm is based on the continuous-time particle filter, which corresponds to the Duncan–Mortensen–Zakai equation. To find the mode of the conditional distribution approximately, the Edgeworth series is used for the conditional probability density function expansion. This approach allows one to significantly reduce the computation time in contrast to finding the mode by estimating the conditional probability density function, for example, by the histogram or the kernel density estimation.The algorithm is proposed for solving approximately the optimal filtering problem for nonlinear continuous-time stochastic observation systems that provides two estimates for the state. These estimates are the minimum mean squared error estimate and the maximum a posteriori estimate. The proposed algorithm is based on the continuous-time particle filter, which corresponds to the Duncan–Mortensen–Zakai equation. To find the mode of the conditional distribution approximately, the Edgeworth series is used for the conditional probability density function expansion. This approach allows one to significantly reduce the computation time in contrast to finding the mode by estimating the conditional probability density function, for example, by the histogram or the kernel density estimation.","PeriodicalId":268263,"journal":{"name":"COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128485590","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":"Symmetry of the flows of Newtonian and non-Newtonian fluids in the diverging and converging plane channels","authors":"A. Fedyushkin, A. A. Puntus, E. Volkov","doi":"10.1063/1.5135676","DOIUrl":"https://doi.org/10.1063/1.5135676","url":null,"abstract":"The results studying various laminar flow regimes in diverging and converging plain channels (diffuser and confusor) with a small opening angle of channels (diverging and converging angles) are presented. The results are obtained for a viscous incompressible fluid by numerical simulation based on solving the Navier-Stokes equations. The paper presents the results concerning the change in the nature of flows from stationary - symmetric to stationary - asymmetric and to non-stationary in the diffuser and confusor in dependence on the Reynolds number. The ranges of existence of these flow regimes in plane diffusers and confusors depending on the Reynolds number for Newtonian, pseudo plastic and dilatants fluids with the Ostwald-de Waele power law for viscosity are numerically found. The transitions of flow regimes in the diffuser from symmetric steady state to the asymmetric one and to the asymmetric unsteady mode in dependence on the Reynolds number are shown. The values of Reynolds number that determine the existence ranges of these flow modes in the cases of Newtonian and non-Newtonian fluids are given.The results studying various laminar flow regimes in diverging and converging plain channels (diffuser and confusor) with a small opening angle of channels (diverging and converging angles) are presented. The results are obtained for a viscous incompressible fluid by numerical simulation based on solving the Navier-Stokes equations. The paper presents the results concerning the change in the nature of flows from stationary - symmetric to stationary - asymmetric and to non-stationary in the diffuser and confusor in dependence on the Reynolds number. The ranges of existence of these flow regimes in plane diffusers and confusors depending on the Reynolds number for Newtonian, pseudo plastic and dilatants fluids with the Ostwald-de Waele power law for viscosity are numerically found. The transitions of flow regimes in the diffuser from symmetric steady state to the asymmetric one and to the asymmetric unsteady mode in dependence on the Reynolds number are shown. The values of Reynolds number that determine th...","PeriodicalId":268263,"journal":{"name":"COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126260529","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":"Simulation of DDoS attack on software defined networks","authors":"Timur R. Bikbulatov, I. Kurochkin","doi":"10.1063/1.5135682","DOIUrl":"https://doi.org/10.1063/1.5135682","url":null,"abstract":"Software defined network technology is attractive in the modern world. In the networking community, very few have escaped its impact. This is a new approach to building the architecture of computer networks. The network management layer and data transfer layer are separated, and network management functions are transferred from routers and switches to software applications running on a separate controller server. The article provides an overview of the most common attacks on software defined networks, their classification and the goals that attackers want to achieve. As software defined network devices and systems enter the market, security in software defined network must be brought up on the agenda. This paper provides a comprehensive overview of the security studies in software-defined networks that have been conducted to date. Both the security improvements that will result from using the software defined network platform and the security issues associated with the platform are discussed. By categorizing existing works, a set of conclusions and proposals for future research directions is presented. What is more, a study was conducted on the impact of DDoS attacks on the software defined network. Appropriate conclusions are drawn from the results obtained after modeling attacks using Mininet technology.Software defined network technology is attractive in the modern world. In the networking community, very few have escaped its impact. This is a new approach to building the architecture of computer networks. The network management layer and data transfer layer are separated, and network management functions are transferred from routers and switches to software applications running on a separate controller server. The article provides an overview of the most common attacks on software defined networks, their classification and the goals that attackers want to achieve. As software defined network devices and systems enter the market, security in software defined network must be brought up on the agenda. This paper provides a comprehensive overview of the security studies in software-defined networks that have been conducted to date. Both the security improvements that will result from using the software defined network platform and the security issues associated with the platform are discussed. By categoriz...","PeriodicalId":268263,"journal":{"name":"COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134285539","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 thermal radiation during zinc sulfide synthesis via combustion in a wet inert gas environment","authors":"A. Markov, I. A. Filimonov","doi":"10.1063/1.5135672","DOIUrl":"https://doi.org/10.1063/1.5135672","url":null,"abstract":"We have presented the numerical results of calculations obtained with the help of a model of the ZnS combustion synthesis in a wet inert gas environment. The model was a modification of the model of the ZnS combustion synthesis on argon developed earlier. The results let us numerically and with the high accuracy estimate separately the heat transfers by both convection, conduction and thermal radiation during the combustion under the conditions stated in the heading. As a result, we are not only able to compare the heat transfers by the convection, conduction and thermal radiation, but also investigate in details the reason of much smaller heat transfer by radiation with respect to convection in the combustion system considered. On one hand, our results agree with data on relative values of heat transfer by convection, conduction and radiation, and on the other hand, they allow us to specify accurately the reason of a smallness of heat transfer by radiation more precisely and reasonably. We have concluded that this is a hot thin cloud of water vapors that is formed in a close vicinity of the igniter, absorbs radiation and prevents the other part of green mixture both from ignition by radiation and the subsequent propagation of the combustion on the basis of radiation heat transfer. In the presented paper a modification of the previous research results was carried out which allows taking into account the influence of water vapor on the radiation heat transfer process during the synthesis of zinc sulfide. At sufficiently high concentration of vapors the model explains the abnormally low values of effective gas permeability coefficients calculated without taking into account the indicated effect.We have presented the numerical results of calculations obtained with the help of a model of the ZnS combustion synthesis in a wet inert gas environment. The model was a modification of the model of the ZnS combustion synthesis on argon developed earlier. The results let us numerically and with the high accuracy estimate separately the heat transfers by both convection, conduction and thermal radiation during the combustion under the conditions stated in the heading. As a result, we are not only able to compare the heat transfers by the convection, conduction and thermal radiation, but also investigate in details the reason of much smaller heat transfer by radiation with respect to convection in the combustion system considered. On one hand, our results agree with data on relative values of heat transfer by convection, conduction and radiation, and on the other hand, they allow us to specify accurately the reason of a smallness of heat transfer by radiation more precisely and reasonably. We have concluded...","PeriodicalId":268263,"journal":{"name":"COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)","volume":"32 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133964047","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 the averaged balloon satellite motions in a plane restricted four-body problem with light pressure","authors":"A. V. Dobroslavskiy, P. Krasilnikov","doi":"10.1063/1.5135670","DOIUrl":"https://doi.org/10.1063/1.5135670","url":null,"abstract":"","PeriodicalId":268263,"journal":{"name":"COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129892209","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":"Stochastic traffic cellular automata model accounting drivers’ behavior","authors":"E. Pegachkova, Anastasia Boboshina","doi":"10.1063/1.5135681","DOIUrl":"https://doi.org/10.1063/1.5135681","url":null,"abstract":"","PeriodicalId":268263,"journal":{"name":"COMPUTATIONAL MECHANICS AND MODERN APPLIED SOFTWARE SYSTEMS (CMMASS’2019)","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132669639","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}