{"title":"Cosmic Gasdynamic Studies at the Chair of Aeromechanics and Gas Dynamics","authors":"K. V. Krasnobaev, V. V. Izmodenov","doi":"10.3103/S0027133025700049","DOIUrl":"10.3103/S0027133025700049","url":null,"abstract":"<p>Problems related to cosmic gasdynamic studies at the Chair of Aeromechanics and Gasdynamics of Lomonosov Moscow State University are discussed. We give main directions and methods of the space studies at our chair. Results of the developed theoretical models describing and predicting physical phenomena in space are presented in details. The models include the interaction of the solar wind with the local interstellar medium and comet atmospheres, motions of the interstellar medium under nonequilibrium ionization.</p>","PeriodicalId":710,"journal":{"name":"Moscow University Mechanics Bulletin","volume":"79 6","pages":"212 - 223"},"PeriodicalIF":0.3,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143698610","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. V. Treschev, E. I. Kugushev, T. V. Shakhova, S. V. Bolotin, Yu. F. Golubev, V. A. Samsonov, Yu. D. Selyutskiy
{"title":"Chair of Theoretical Mechanics and Mechatronics","authors":"D. V. Treschev, E. I. Kugushev, T. V. Shakhova, S. V. Bolotin, Yu. F. Golubev, V. A. Samsonov, Yu. D. Selyutskiy","doi":"10.3103/S0027133025700037","DOIUrl":"10.3103/S0027133025700037","url":null,"abstract":"<p>In the paper, scientific and pedagogical activities of the Chair of Theoretical Mechanics and Mechatronics of the Faculty of Mechanics and Mathematics of Lomonosov Moscow State University have been described. Some scientific results obtained in recent years by current employees and the most significant scientific results of former employees of the chair have been presented.</p>","PeriodicalId":710,"journal":{"name":"Moscow University Mechanics Bulletin","volume":"79 6","pages":"200 - 211"},"PeriodicalIF":0.3,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143698609","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}
V. A. Sadovnichii, V. V. Aleksandrov, J. L. Gordillo-Dominguez, A. A. Konovalenko, P. Yu. Sukhochev, K. V. Tikhonova, N. E. Shulenina
{"title":"Galvanic Correction of Neural Control of Gaze Stabilization, Part 2","authors":"V. A. Sadovnichii, V. V. Aleksandrov, J. L. Gordillo-Dominguez, A. A. Konovalenko, P. Yu. Sukhochev, K. V. Tikhonova, N. E. Shulenina","doi":"10.3103/S0027133024700201","DOIUrl":"10.3103/S0027133024700201","url":null,"abstract":"<p>The article shows an experimental (part 2) improvement in the\u0000stabilization of the gaze under galvanic vestibular stimulation.</p>","PeriodicalId":710,"journal":{"name":"Moscow University Mechanics Bulletin","volume":"79 5","pages":"149 - 155"},"PeriodicalIF":0.3,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994487","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":"Dependence of the Size of the Reachable Set on Parameters in a Second-Order Linear System","authors":"A. S. Klyuev","doi":"10.3103/S0027133024700237","DOIUrl":"10.3103/S0027133024700237","url":null,"abstract":"<p>The oscillating linear time-invariant system of second order with time-varying bounded control is considered. The reachable set size is studied with respect to bounded parameters of the system. The reachable set size is characterized by a distance from the origin to the most or least distant point of the set in the Euclidean norm. For one case study, the set size is found to be monotonous in all parameters of the system.</p>","PeriodicalId":710,"journal":{"name":"Moscow University Mechanics Bulletin","volume":"79 5","pages":"172 - 177"},"PeriodicalIF":0.3,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994488","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":"The d’Alambert Principle and the Classical Relativity in Lagrangian Mechanics","authors":"B. Jovanović","doi":"10.3103/S0027133024700213","DOIUrl":"10.3103/S0027133024700213","url":null,"abstract":"<p>In this paper, we present an invariant formulation of the d’Alambert principle and classical time-dependent Lagrangian mechanics with holonomic constraints from the perspective of moving frames.</p>","PeriodicalId":710,"journal":{"name":"Moscow University Mechanics Bulletin","volume":"79 5","pages":"156 - 164"},"PeriodicalIF":0.3,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994599","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":"Guaranteeing Estimation Method for Determining Failures in a Redundant Sensor Unit","authors":"A. I. Matasov, E. V. Shestakova","doi":"10.3103/S0027133024700249","DOIUrl":"10.3103/S0027133024700249","url":null,"abstract":"<p>An algorithm is proposed to determine failures for a redundant inertial sensor unit by means of the guaranteeing estimation method. The numerical testing confirms the efficiency of the proposed algorithm.</p>","PeriodicalId":710,"journal":{"name":"Moscow University Mechanics Bulletin","volume":"79 5","pages":"178 - 182"},"PeriodicalIF":0.3,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994489","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":"Symmetric Cavitation Flow around a Cylinder with a Point Effluent on Its Surface","authors":"A. A. Spasova, S. L. Tolokonnikov","doi":"10.3103/S0027133024700225","DOIUrl":"10.3103/S0027133024700225","url":null,"abstract":"<p>The problem of a symmetric stationary cavitation flow around a cylinder by an infinite flow of ideal incompressible weightless fluid in the presence of a given intensity point effluent located at the front point of the cylinder is considered. The exact solution to the problem is constructed by mapping the areas of change in the complex potential and complex flow velocity onto the area of change in the auxiliary parametric variable. A parametric analysis of the problem is performed. For a wide range of values of the cavitation number, the dimensionless flow rate, the shape and dimensions of the cavitation cavity, and the values of the drag coefficient are found.</p>","PeriodicalId":710,"journal":{"name":"Moscow University Mechanics Bulletin","volume":"79 5","pages":"165 - 171"},"PeriodicalIF":0.3,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994485","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":"The Polynomials of Mixed Degree in Problems of Micropolar Theory of Elasticity","authors":"A. V. Romanov","doi":"10.3103/S0027133024700171","DOIUrl":"10.3103/S0027133024700171","url":null,"abstract":"<p>In this paper, a variational principle of Lagrange and the Ritz method with generalized reduced and selective integration for mixed piecewise polynomial functions are used to obtain a stiffness matrix and a system of linear algebraic equations for micropolar theory of elasticity. This approach is implemented for anisotropic, isotropic, and centrally symmetric material in case of nonisothermal process. The cube problem is considered. The performance for finite element with mixed piecewise polynomial functions is exposed.</p>","PeriodicalId":710,"journal":{"name":"Moscow University Mechanics Bulletin","volume":"79 4","pages":"130 - 136"},"PeriodicalIF":0.3,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142410103","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":"Creep Curves Generated by a Nonlinear Flow Model of Tixotropic Viscoelastoplastic Media Taking into Account Structure Evolution","authors":"A. V. Khokhlov","doi":"10.3103/S002713302470016X","DOIUrl":"10.3103/S002713302470016X","url":null,"abstract":"<p>We continue the systematic analytical study of the nonlinear Maxwell-type constitutive equation for shear flow of tixotropic viscoelastoplastic media formulated in the previous article. It accounts for interaction of deformation process and structure evolution, namely, the influence of the kinetics of formation and breakage of chain cross-links, agglomerations of molecules, and crystallites on viscosity and shear modulus and deformation influence on the kinetics. The constitutive equation is governed by an increasing material function and six positive parameters. Assuming that the stress is constant (in order to simulate creep conditions), we formulate the set of two nonlinear differential equations for two unknown functions (namely, strain and cross-links density) and obtain its exact general solution in explicit form. We examine the properties of creep curves generated by the model for arbitrary material function and material parameters and analyze dependence of creep curves and cross-links density on time, stress level, initial cross-links density, and material parameters governing the model. Thus, we prove that the model not only describes basic phenomena observed for simple shear flow of shear thinning fluids, but can simulate creep, relaxation, and other phenomena observed for solid bodies.</p>","PeriodicalId":710,"journal":{"name":"Moscow University Mechanics Bulletin","volume":"79 4","pages":"119 - 129"},"PeriodicalIF":0.3,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142410092","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":"Real-Time Determination of Heat Turn Beginning Using Inertial Sensors","authors":"A. A. Petrov, V. V. Latonov, A. P. Kruchinina","doi":"10.3103/S0027133024700183","DOIUrl":"10.3103/S0027133024700183","url":null,"abstract":"<p>Capturing human movements and determining their features are often necessary in the development of devices worn by persons or used by them in daily work. In this regard, the problem of detecting the beginning of rotation seems to be relevant and has many applications in bionavigation and biomechanics. One of the main difficulties in these tasks is minimizing the delay in detecting the motion. In this paper the problem of detecting the head turn beginning by inertial sensors data fixed on it—three-axis accelerometer and CRS—is considered. The requirement to determine the head turn beginning appears when trying to solve the problem of supplementing vestibular information under special conditions, for example, to solve the problem of the vestibulo-sensory conflict that occurs in a state of weightlessness.</p>","PeriodicalId":710,"journal":{"name":"Moscow University Mechanics Bulletin","volume":"79 4","pages":"137 - 143"},"PeriodicalIF":0.3,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142410107","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}