Yurii Shokin

Institute of Computational Technologies

Development of technology and technical systems significantly increases in the volume of information. Traditional methods for designing, manufacturing and operating of technical systems do not allow processing such volumes of information. In this regard, the modern strategy for creating technical systems is based on the use of digital twins. Solvin...

The probabilistic aspects of multiscale modeling of the fracture of heterogeneous structures are considered. An approach combining homogenization methods with phenomenological and numerical models of fracture mechanics is proposed to solve the problems of assessing the probabilities of destruction of structurally heterogeneous materials. A model of...

This paper is a continuation of [38]. The analysis of the modified partial differential equation (MDE) of the constant-wind-speed linear advection equation explicit difference scheme up to the eighth-order derivatives is presented. In this paper the authors focus on the dissipative features of the Beam–Warming scheme. The modified partial different...

The analysis of the modified partial differential equation (MDE) of the constant wind speed advection equation explicit difference scheme up to the eighth order with respect to both space and time derivatives is presented. So far, in majority of publications this modified equation has been derived mainly as a fourth-order equation. The MDE is prese...

The overview maps of tsunami hazard for the Far East coast of Russian Federation are created. The methodological basis of the PTHA (Probabilistic Tsunami Hazard Assessment) approach are discussed, as well as the problems of constructing seismotectonic models of the main tsunamigenic zones, mathematical models and algorithms for calculating probabil...

In this work we present the new mathematical models and the results of numerical studies of cell death processes – apoptosis and necrosis – in ischemic stroke, myocardial infarction and Alzheimer’s disease. General questions of aseptic inflammation modeling are considered on the example of dynamics of inflammation factors during wound healing. New...

Further development of calculation and experimental analysis methods and ensuring their security against risk criteria for the prevention of accidents and disasters is considered. Of particular importance in this direction are the methods and technologies of both computational and physical modeling and analysis of the limiting states of structures...

In the present paper we propose a mathematical model and study numerically the functioning of the p53 tumors suppressor protein and the direct positive connection of microRNA molecules related to it. The adequacy of the model is confirmed by qualitative concordance of calculation results with the experimental data concerning transactivation of spec...

The mathematical model of the dynamics of the tumor markers network p53-Mdm2-microRNA for microRNA class with a direct positive connection with p53 was formulated. Numerical investigation of the microRNA functioning in conditions of the deregulation of p53 and p53-Mdm2-network was carried out. The deregulation of microRNA in detail was studied. The...

Improvement of advanced technologies in the field of high-velocity hydrodynamics is strategically significant in terms of national security and stable and long-term growth of the economy due to regional development in Siberia and the Arctic, as well as support of Russia’s scientific and technological authority in the global arena. The practice of c...

The discussed challenge and its prospects in mining geoinformation science are connected with Big Data concept—flows of large sets of various data on mining. The authors describe Big Data technology and its general implementation on mini-clusters using Hadoop and MapReduce with case studies presented.

The numerical simulation of the run-up of long surface waves on a plane slope is presented. Using a method based on the combination of the TVD scheme and the SPH method the shallow water approximation is applied to the solution of the well known model problem of a run-up of a wave approaching from an area of constant depth towards a plane slope. Th...

Abstract: In the present paper we study features and abilities of the combined TVDtSPH method relative to problems of numerical simulation of long waves runup on a shore within the shallow water theory. The results obtained by this method are compared to analytic sol utions and to the data of laboratory experiments. Examples of successful applicati...

In the present paper we study features and abilities of the combined TVD+SPH method relative to problems of numerical simulation of long waves runup on a shore within the shallow water theory. The results obtained by this method are compared to analytic solutions and to the data of laboratory experiments. Examples of successful application of the T...

The present paper is focused on the mathematical model describing the dynamics of an artificial heart valve and the method of its numerical solution. The results of performance simulation are presented for the tricuspid valve of perfect form and the biological prosthesis ‘Uniline’.

Fracture propagation caused by fluid pumping is in the focus of the report. The most popular approaches and problem statements used for the propagation simulation are described. Methods of simulation of the main processes that take place during the fracture propagation are outlined. There processes are the follows: rock deformation and rock breakin...

In this study, a new numerical model based on the method of particles in cells, which differs in principle from the schematic of particles in Harlow cells by the fact that the particles have their own velocity and, therefore, boundaries with a vacuum are not spread, is proposed for the first time. The model makes it possible to pass the stage of th...

An approach to the computer simulation of a tsunami run-up on the coast is presented, based on nested grids and the large-particle method. The computational algorithms are based on the classical equations of shallow-water theory. The main elements of the developed computational technology are described and the results are given of the verification...

The derivation of shallow-water models taking into account the dispersion is based on the Euler equations for an ideal incompressible fluid on a rotating sphere, the mobility of the bottom surface being taken into account, while further passage along the hierarchy from completely nonlinear equations with dispersion towards simplifications proceeds...

Рассмотрена информационная система для поддержки научных исследований с использованием данных спутникового мониторинга, в основе которой лежит технология представления файлового архива данных дистанционного зондирования Земли как единого многомерного информационного пространства — технология hVault. Возможности этой системы рассмотрены на примере р...

Results of a numerical simulation of the action of distant tsunamis on the coast of the Russian Far East are presented. It is shown that waves generated by focuses of the strongest M9 earthquakes in the region of South Chilean coast, as well as in the region of Papua New Guinea and Solomon Islands, are most dangerous for this coast. Other tsunamige...

Digital simulation of disorders in the p53 and Mdm2 protein system, involved in repair of DNA defects and in many vital processes, including tumor formation, neurodegeneration, and aging, was carried out on the base of functional nonlinear octoparametric mathematical model. Stress situations were studied, associated with emergence of imbalance in p...

Transformations of consistent discrete approximations of the first derivatives in the passage from Cartesian coordinates to an orthogonal curvilinear system and transformations of discrete operations of vector analysis on skewed grids on a plane are studied. It is established that the transformation algorithm for discrete operators preserves symmet...

The ascend and evolution of an axisymmetric gas bubble are studied numerically using an inviscid incompressible potential flow model. The volume of the gas bubble varies adiabatically. The transition from a simply connected bubble to a doubly connected toroidal one and its interaction with the free surface are simulated. The change in connectedness...

Mathematical simulation of the time course of p53 and Mdm2 protein concentrations during their interactions was carried out. The system states corresponding to threatened uncontrolled apoptotic cell death accelerating aging processes and to situation with hypersuppression of p53-dependent apoptosis fraught with high risk of cancer were modeled. New...

The authors study the surface waves which are generated by the submarine landsliding on a curvilinear bottom slope of a deep reservoir. The shallow water models of the first and second approximations are used to describe the surface waves. An underwater landslide is described by the model of motion of a "quasi-deformed" body on curvilinear surface...

Performing modern research requires serious instrumental and technological support. One of the key sources of such securing is information technology, which are widely used in both research processes and in various tasks of the scientific activity: the publication of results, information storage and processing, document and project management, etc....

A model of underground coal gasification (UCG) is proposed in the paper. In the process of UCG, coal burning at the interface (so-called ‘fire-face’) between the coal mass and the gas chamber (called fire drift) is transformed into a gas mixture. A certain part of gas is filtered through the coal mass and rock. This process is described by Darcy’s...

In recent years, natural and anthropogenic disasters that take human lives and pollute the environment have become more frequent not only in Russia but also throughout the world. The authors present a model that predicts and prevents disasters; the model is based on the Siberian Federal District data.

This paper is focused on the development of numerical algorithms based on the natural element method for the solution of problems of incompressible fluid dynamics with free boundaries.

The general scheme for processing the results of the area risk monitoring, requirements for the data bank structure and functioning are presented. The algorithms of processing statistical and expert information for obtaining quantitative estimates of the area risks and creating thematic maps of different detailization of the considered territories...

A series of two- and three-dimensional stationary problems of a viscous incompressible fluid flow in a channel caused by a given pressure differential is studied in the paper. It is shown that the solution to this problem is not unique. A numerical method allowing one to obtain the solution without specifying additional conditions for the velocity...

We present the results of numerical modelling of surface wave generation by the movement of submerged deformable body along the slope, which simulates the real coastal slope. The multiparametric computations are carried out within the shallow water approximation that allowed to determine the dependence of wave pattern on the depth of landslide subm...

Parallel implementation of finite volume time domain method (FVTD) described in this paper is being developed for numerical simulations in the optics of nano-structured metal-dielectric composites. The problem is complicated by the dispersive behaviour of the dielectric function in metals, which is introduced into the system of equations through th...

The main reason for the generation of tsunamis is the deformation of the bottom of the ocean caused by an underwater earthquake. Usually, only the vertical bottom motion is taken into account while the horizontal co-seismic displacements are neglected in the absence of landslides. In the present study we propose a methodology based on the well-know...

This paper reviews mathematical models using the approximation of a slow envelope amplitude of an electromagnetic field and implementing the corresponding numerical algorithms for mathematical modelling of nonlinear effects in optical fibers. Some examples illustrating the use of mathematical simulation methods for solving actual physical problems...

1] A record of a tsunami event riding on the usual tide signal was recorded by a floating-type tidal gauge installed in the port of Yafo, Israel. The tsunami was triggered by an earthquake in the Aegean Sea on 9 July 1956. This paper presents a retrieval of tsunami waves from the record. At the first stage of the study an attempt had been undertake...

The paper presents the review of the development of Computational Fluid Dynamics and Aerodynamics in the time frame 1960-2007 in the USSR and, later, in Russia. The organization of scientific investigations in the given fields is shown. Reviewed are the theory of difference schemes, splitting methods, irregular grids, and the particle-in-cell metho...

Siberia Integrated Regional Study (SIRS, http://sirs.scert.ru) is a Northern Eurasia Earth Science Partnership Initiative (NEESPI, http://neespi.org) mega project co-ordinating national and international activity in the region in line with Earth System Science Program (ESSP) approach. It is aimed to understand dynamics of dynamics of regional envir...

Numerical simulation is used for studying the formation and outflow of a jet of low-temperature plasma generated by water evaporation induced by a high-energy electric pulse discharge in a half-closed cylindrical volume. It is shown that a stable bounded comet-shaped high-pressure zone is formed in the leading part of the jet moving in the vertical...

The results of numerical simulation of the self-focusing process of a laser pulse in a dielectric based on the nonlinear Schrödinger equation (NSE) with cubic nonlinearity are presented in the paper for initial Gauss and ring distributions. The critical power levels for the collapse of these initial distributions are determined. The Crank-Nicholson...

Several two- and three-dimensional problems for the Navier-Stokes equations are solved numerically using the minimal residual iterative method. The iteration method uses a matrix of iteration parameters. The choice of elements of this matrix is based on the condition of minimization of residual norms. It is shown that two-dimensional and three-dime...

The book expounds in a popular form basic elements of a technology for generating adaptive grids in multi-dimensional domains and surfaces. The technology relies on numerical solutions of inverted Beltrami and diffusion equations

Efficient statistical tests, e.g. recently suggested “Book Stack” test, are successfully applied to detect deviations from randomness in bit sequences generated by stream ciphers such as RC4 and ZK-Crypt, as well as by block cipher RC6 (with reduced number of rounds). In case of RC6 a key recovery attack is also mounted. The essence of the tests is...

This paper presents a method for the calculation of tsunami wave runup on an actual coast. This method consists in preliminary study of peculiarities of wave patterns near the coast for a series of simplified model water areas inheriting the basic characteristics of the coastal zone, and in the use of the obtained results for the interpretation of...

Catastrophic tsunamis that flooded the ocean coast in the past had taken many human lives and destroyed the infrastructure of the coastal areas in the Pacific and elsewhere. Recent tragic events in the Indian Ocean motivated governments to develop new and improve the existing tsunami warning systems capable to mitigate the impact of catastrophic ev...

The paper addresses numerical modeling of electric and magnetic fields in fiber media generally described by Maxwell equations. Complex microstructures and composite materials in modern optics devices require special techniques to be modeled. These peculiarities are all considered in FVTD method proposed. High computational complexity inherent to m...

The performance gap between supercomputers and personal workstations is growing. Yet supercomputing resources are scarce and carefully managed. Gaining access to a leading national supercomputing centre requires a considerable amount of work comparable to the amount of work needed to get a paper published in a leading scientific journal. This raise...

The solution of new classes of application problems in the fields of continuum mechanics, including the problems of three-dimensional aerodynamics and hydrodynamics, space physics, environmental science often require considerable computer resources which are often too great even for the leading and best equipped research centers. We believe this pr...

]. Nowadays the method of differential approximation is more and more used in the analysis of the properties of difference schemes (e.g., refs. [I-9]). The essence of the method is, that investigation of the properties of difference schemes leads to investigation of differential representations and differential approximations. The differential repr...

Using numerical modeling, we studied the formation and propagation of a cloud of finely dispersed aluminum particles generated by a special unit under the action of high-temperature combustion products from solid propellant gas generator, as well as the ignition conditions of these particles. We used the Favre-averaged system of Navier-Stokes equat...

Brief information of the INTAS funded project is given. The project focuses on the mathematical description of the breaking-wave-induced mixing of coastal wa-ters. The analysis involves both tackling a number of theoretical issues (characteri-zation/modeling of breaking waves, of the generation/evolution of large-scale vertical structures, of the i...

We propose a numerical method for solving nonstationary Maxwell equations on unstructured triangular grids, which is based on the finite volume method. We give the results of test calculations which confirm the second order of convergence of the method both for homogeneous media and media with space-variable dielectric permittivity.

We describe results obtained in numerical investigation of tsunami generation by a moving submerged landslide which is simulated by a solid body sliding down a slope. We perform complex multiparameter calculations by algorithms based on a hierarchy of wave hydrodynamics models comprising shallow water equations and full hydrodynamical equations of...

In this paper we consider an explicit difference predictor-corrector scheme of the second order of approximation for solving one-dimensional nonlinear shallow water equations, which yields nonoscillating profiles of discontinuous solutions with the proposed choice of the approximation viscosity of the scheme. For linearized shallow water equations...

Collecting and sharing timely, reliable and accurate information during a crisis is critical to improving humanitarian response, maximizing resources and minimizing human suffering. The faster humanitarian organizations are able to collect, analyse and disseminate critical information, the more effective the response becomes and the more lives are...

Several new possibilities to enhance information capacity of data transmission by integration of several key technologies such as dispersion management, wavelength-division multiplexing and optical regeneration of signals are discussed. Mathematical modelling results may be used for upgrade of existing fiber links and design of new generation of lo...

Some invariant and noninvariant finite-difference schemes for the solution of hyperbolic equations are discussed and compared. It is shown that invariant schemes reflect the characteristics of exact solutions more precisely, both qualitatively and quantitatively. The inaccuracy of noninvariant finite-difference schemes derives primarily from the pe...

The present paper gives the numerical simulation of tsunami generation and propagation in the ocean with real bathymetry. For the describing of this processes nonlinear shallow water equations are used, which are solved with the help of finite-difference method. Here is considered the problem of tsunami generation by bottom displacements, moving wi...

The paper addresses the problems of construction of numerical models for generation and transformation of long surface waves induced by landslides. The authors specify the basic mathematical models, expound the principles, on which the computational algorithms are constructed, and discuss the computational result.

A finite volume method to solve Maxwell’s equations on partially unstructured grids for the media having jump discontinuities in the electric permittivity coefficient ε has been presented. Test numerical simulations prove the second order accuracy of the method proposed.

The new approach to construction of monotonic nonlinear difference second order schemes, based on the investigation of the differential approximation of a scheme, is presented. One of possible formulas for the definition of approximating viscosity is given, which leads to the coincidence of the constructed scheme with the Harten’s TVD scheme. The k...