Latest releases in the series

An approach to using Golang programs for the specification and verification of distributed systems (p. 1-9)
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The work is devoted to an attempt to use Golang programs for the specification and verification of distributed systems. The A.P. Ershov Institute of Informatics Systems, SB RAS, has been developing this approach for years. A distributed system described in terms of an SDL specification, which is…

On the History of the START project (1985–1988) (p. 11-21)
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The paper presents the history of START, an ad-hoc team created in 1985 to develop fifth-generation computers in response to the "Japanese challenge". As a new form of the organization and implementation of scientific and technical projects during the perestroika, START contributed to the…

Creating a prototype of an IoT development web platform (p. 23-31)
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Nowadays, the creation of custom electronic devices of varying degrees of complexity is available for a wide audience. The applications vary from simple devices such as clocks and weather stations to automated homes and manufacturing control systems. In the last decade, the Arduino platform [1] has…

Comparison of ELMO-based models on the named entity recognition task (p. 33-41)
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This paper presents a comparison of ELMO-based models. The comparison was performed on data in the Russian language for the task of named entity recognition (NER). The paper also discusses a comparison of the architectures based on the Simple Recurrent Unit (SRU) and Gated Recurrent Unit (GRU). All…

Extraction of the author’s terminology and definitions from mathematical texts (p. 43-51)
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This paper describes a pipeline for extracting the author’s terms and definitions from mathematical texts. We used two models: one, for detecting mathematical formulas to clear text from noise and the other, for converting images into LaTeX formulas to restore the deleted formulas. Experimental data…

On an inverse problem arising in the theory of propagation of nonlinear waves (p. 1–7)
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In this paper, we consider a one-dimensional inverse source problem for the Hopf equation. We show that it is uniquely solvable in the class of finite smoothness.

Modeling of seismic wave propagation during an earthquake in complex heterogeneous media (p. 9–16)
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The direct dynamic problem of elasticity theory is solved numerically taking into account the energy dissipation caused by viscous (internal) friction, which models the formation and propagation of seismic waves from earthquakes. The problem is written in the form of dynamic equations of elasticity…

On the possible relationship between remote seismic activations and strong earthquakes in southeast regions of Eurasia and adjacent seismic focal zones (p. 17–27)
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Using the example of the 14 largest earthquakes (MS ≥ 7.9) in area: −30–50°N, 78–180°E, the possible geodynamic interconnectedness of the processes of focus preparation with a preliminary moderate seismic activation in the subduction or collision zones crossing the areas of a future earthquake…

Layered flows of high-temperature suspensions (p. 29–39)
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The paper numerically studies the flow of a high-temperature twophase mixture in a gravity field. Thermodynamically consistent equations of twospeed hydrodynamics of a suspension with a foreign impurity are developed within the framework of the conservation law method. The numerical non-stationary…

On one inverse source problem for a poroelasticity system (p. 41-47)
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The inverse problem of determining a distributed source from a porodynamic system described by three elastic parameters in a reversible hydrodynamic approximation is considered. A theorem on solvability in the class of twice continuously differentiable in time and having Fourier transforms in the…

On the polar vortex streamer dynamics (p. 1-8)
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Potential vorticity (PV) streamers and cutoffs are indicators to the Rossby wave breaking (RWB) near the extratropical tropopause. In the Rossby waves breaking, the formation of elongated high-PV stratospheric air tongues extending to the equator and tropospheric low PV air tongues extending to the…

Study of the in fluence of Atlantic water on the ice cover state in the Eurasian basin of the Arctic Ocean using numerical simulation (p. 9-19)
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A numerical simulation of the water and sea ice dynamics of the Arctic Ocean was carried out to identify the physical mechanisms that determine the variability of the state of the ice cover. For the research, we used the coupled ocean-ice regional numerical model of the North Atlantic and the Arctic…

Simulation of the near-bottom water warming in the Laptev Sea in 2007-2008 (p. 21-30)
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The Laptev Sea, one of the most severe Arctic shelf seas is the focus of the international research on account of a pronounced climate change (warming of the atmosphere temperature, lengthening of the summer open-water season, reduction of the ice extent, rapid coastal erosion). In recent years, as…

The Novosibirsk reservoir hydrothermal regime model (p. 31-49)
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In this paper, the adaptation of the SibCIOM three-dimensional thermodynamic model is considered that allows modeling a three-dimensional velocity and temperature distribution, as well as a two-dimensional field of the ice cover for the Novosibirsk reservoir with seasonal changes in the water level…

Reproduction of runoff hydrograph in the Lena River basin with a hydrologically correct digital elevation model (p. 51-58)
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A hydrologically correct digital model of the bottom topography of the Lena River basin with a resolution of (1/3)° x (1/3)° is constructed. Based on the linear model of forming a water balance in the river-bed network and a model network of river channels schematized in the form of a graph of a…

Numerical comparison of the source identification problem with the continuation problem for the air quality evaluation scenario (p. 59-66)
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In the data assimilation algorithms for the air quality applications, the source identification problem can be considered as an auxiliary one for the solution of the model state function continuation problem. The algorithm based on the ensembles of the adjoint problem solutions is applied to solve…

The use of satellite information to estimate smoke emissions parameters of power stations (p. 67-76)
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The satellite observations of smoke plumes from the pipes of power stations make possible to obtain prompt information about the processes of impurities distribution in the atmosphere and about the source parameters. This paper proposes a method of numerical reconstruction of characteristics of the…

Numerical experiments for solving Maxwell's equations in thin domains with a new implicit scheme (p. 1-8)
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Conditional stability of explicit schemes in finite differences complicates the choice of a time step. The increase in the number of the grid nodes for more precise computations and the corresponding space step decrease leads to the increase in computer costs due to the decreasing of the time step…

Numerical models of the electrostatic shock waves (p. 9-16)
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The self-consistent evolution of the ion-acoustic collisionless shock with shock-reflected ions is numerically studied with kinetic simulations. We want to compare different approaches to the shock simulation based on the PIC-method. The results of one-dimensional fully kinetic simulation for both…

The portable and scalable kinetic plasma simulation code for hybrid supercomputers (p. 17-28)
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Today the method for the development of portable numerical simulation programs is very important because of the two main reasons. The first reason is the diversity of supercomputer architectures in Top500 and the second one is a demand for using the most powerful computers to simulate, for example…

Radial inflow model in the near-wellbore zone of exploitation wells (p. 29-35)
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The paper reviews the problem of forecasting the possible maximum pressure at the well-head, at the well-bore and at near-wellbore zone of reservoir during the process of new stimulation technology like reactive chemistry application. The technology provides stimulation by thermobaric effects. This…

Modeling of a heterophase flow in permeable zones of the lithosphere (p. 37-47)
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This paper investigates a magma flow in permeable zones of the lithosphere. The model equations describing the dynamics of saturated porous media both without tangential stresses and with them are presented. The phenomenological method used for deriving the equations provides the thermodynamic…

On derivation of the size distribution of cloud droplets from the phase function (p. 49-56)
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This paper deals with an ill-posed problem to determine the size distribution for water drops in a cloud from a given scattering phase function. Numerical experiments have shown that a method based on non-negative least squares with additional requirements of smoothness can be used to solve the ill…

Supercomputer-aided comparison of the efficiency of using different mathematical statements of the 3D geophysical problem (p. 57-66)
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In order to create systems of vibroseismic monitoring for earthquakeprone areas it is needed to carry out the simulation of seismic wave propagation in the media typical of volcanic structures. To this end it is required to develop supercomputer technologies for decreasing the computation time and…

Supercomputer simulation of a gravitating gaseous circumstellar disk using SPH (p. 67-75)
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New parallel algorithm is developed for simulating the dynamics of a thin circumstellar disk. It is based on the combination of a gridless method of smoothed particle hydrodynamics (SPH) and the grid-based convolution method for calculating a gravitational potential. To develop the algorithm, we…