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In this paper, the structure of a shock wave in a binary gas mixture is studied on the basis of direct solution of the Boltzmann kinetic equation. The conservative projection method is used to evaluate the collision integral in the kinetic equation. The applied evaluation formulas and numerical methods are described in detail. The model of hard spheres is used as an interaction potential of molecules. Numerical simulation is performed using the developed simulation environment software, which makes it possible to study both steady and non-steady flows of gas mixtures in various flow regimes and for an arbitrary geometry of the problem. Modeling is performed on a cluster architecture. Due to the use of code parallelization technologies, a significant acceleration of computations is achieved. With a fixed accuracy controlled by the simulation parameters, the distributions of macroscopic characteristics of the mixture components through the shock wave front were obtained. Computations were conducted for various ratios of molecular masses and Mach numbers. The total accuracy of at least 1% for the local values of molecular density and temperature and 3% for the shock front width was achieved. The obtained results were compared with existing computation data. The results presented in this paper are of theoretical significance, and can serve as a test computation, since they are obtained using the exact Boltzmann equation.

The purpose of this work is to develop a universal computer program (solver) which solves kinetic Boltzmann equation for simulations of rarefied gas flows in complexly shaped devices. The structure of the solver is described in details. Its efficiency is demonstrated on an example of calculations of a modern many tubes Knudsen pump. The kinetic Boltzmann equation is solved by finite-difference method on discrete grid in spatial and velocity spaces. The differential advection operator is approximated by finite difference method. The calculation of the collision integral is based on the conservative projection method.

In the developed computational program the unstructured spatial mesh is generated using GMSH and may include prisms, tetrahedrons, hexahedrons and pyramids. The mesh is denser in areas of flow with large gradients of gas parameters. A three-dimensional velocity grid consists of cubic cells of equal volume.

A huge amount of calculations requires effective parallelization of the algorithm which is implemented in the program with the use of Message Passing Interface (MPI) technology. An information transfer from one node to another is implemented as a kind of boundary condition. As a result, every MPI node contains the information about only its part of the grid.

The main result of the work is presented in the graph of pressure difference in 2 reservoirs connected by a multitube Knudsen pump from Knudsen number. This characteristic of the Knudsen pump obtained by numerical methods shows the quality of the pump. Distributions of pressure, temperature and gas concentration in a steady state inside the pump and the reservoirs are presented as well.

The correctness of the solver is checked using two special test solutions of more simple boundary problems — test with temperature distribution between 2 planes with different temperatures and test with conservation of total gas mass.

The correctness of the obtained data for multitube Knudsen pump is checked using denser spatial and velocity grids, using more collisions in collision integral per time step.

The paper simulates a mixture of gases in a multi-stage micro-pump and evaluates its effectiveness at separating the components of the mixture. A device in the form of a long channel with a series of transverse plates is considered. A temperature difference between the sides of the plates induces a radiometric gas flow within the device, and the differences in masses of the gases lead to differences in flow velocities and to the separation of the mixture. Modeling is based on the numerical solution of the Boltzmann kinetic equation, for which a splitting scheme is used, i. e., the advection equation and the relaxation problem are solved separately in alternation. The calculation of the collision integral is performed using the conservative projection method. This method ensures the strict fulfillment of the laws of conservation of mass, momentum, and energy, as well as the important asymptotic property of the equality of the integral of the Maxwell function to zero. Explicit first-order and second-order TVD-schemes are used to solve the advection equation. The calculations were performed for a neon-argon mixture using a model of solid spheres with real molecular diameters and masses. Software has been developed to allow calculations on personal computers and cluster systems. The use of parallelization leads to faster computation and constant time per iteration for devices of different sizes, enabling the modeling of large particle systems. It was found that the value of mixture separation, i. e. the ratio of densities at the ends of the device linearly depends on the number of cascades in the device, which makes it possible to estimate separation for multicascade systems, computer modeling of which is impossible. Flows and distributions of gas inside the device during its operation were analyzed. It was demonstrated that devices of this kind with a sufficiently large number of plates are suitable for the separation of gas mixtures, given that they have no moving parts and are quite simple in manufacture and less subject to wear.

Events and character extraction from narratives is a fundamental task in text analysis. The application of event extraction techniques ranges from the summarization of different documents to the analysis of medical notes. We identify events based on a framework named “four W” (Who, What, When, Where) to capture all the essential components like the actors, actions, time, and places. In this paper, we explore two prominent techniques for event extraction: statistical parsing of syntactic trees and semantic role labeling. While these techniques were investigated by different researchers in isolation, we directly compare the performance of the two approaches on our custom dataset, which we have annotated.

Our analysis shows that statistical parsing of syntactic trees outperforms semantic role labeling in event and character extraction, especially in identifying specific details. Nevertheless, semantic role labeling demonstrate good performance in correct actor identification. We evaluate the effectiveness of both approaches by comparing different metrics like precision, recall, and F1-scores, thus, demonstrating their respective advantages and limitations.

Moreover, as a part of our work, we propose different future applications of event extraction techniques that we plan to investigate. The areas where we want to apply these techniques include code analysis and source code authorship attribution. We consider using event extraction to retrieve key code elements as variable assignments and function calls, which can further help us to analyze the behavior of programs and identify the project’s contributors. Our work provides novel understandings of the performance and efficiency of statistical parsing and semantic role labeling techniques, offering researchers new directions for the application of these techniques.

Results obtained during practical training session on MPI during high perfomance computing summer school MIPT-2010 are discussed. MPI technology were one of technologies proposed to participants for realization of project. 3D version of Conway’s Game of Life was proposed as a project. Algorithms used in the development, theoretical and practical assessment of their scalability is analyzed.

GIS INTEGRO is the geo-information software system forming the basis for the integrated interpretation of geophysical data in researching a deep structure of Earth. GIS INTEGRO combines a variety of computational and analytical applications for the solution of geological and geophysical problems. It includes various interfaces that allow you to change the form of representation of data (raster, vector, regular and irregular network of observations), the conversion unit of map projections, application blocks, including block integrated data analysis and decision prognostic and diagnostic tasks.

The methodological approach is based on integration and integrated analysis of geophysical data on regional profiles, geophysical potential fields and additional geological information on the study area. Analytical support includes packages transformations, filtering, statistical processing, calculation, finding of lineaments, solving direct and inverse tasks, integration of geographic information.

Technology and software and analytical support was tested in solving problems tectonic zoning in scale 1:200000, 1:1000000 in Yakutia, Kazakhstan, Rostov region, studying the deep structure of regional profiles 1:S, 1-SC, 2-SAT, 3-SAT and 2-DV, oil and gas forecast in the regions of Eastern Siberia, Brazil.

The article describes two possible approaches of parallel calculations for data processing 2D or 3D nets in the field of geophysical research. As an example presented realization in the environment of GRID of the application software ZondGeoStat (statistical sensing), which create 3D net model on the basis of data 2d net. The experience has demonstrated the high efficiency of the use of environment of GRID during realization of calculations in field of geophysical researches.

Amid the ongoing trend of rapid urbanization and the intensive development of megacities and large cities worldwide, the impact of man-made vibrations on residential structures and infrastructure is increasing. The operation of subway systems, construction using pile-driving and drilling equipment, and heavy traffic have become active sources of wave disturbances, which can be a decisive factor in reducing the structural stability of buildings and, consequently, their long-term reliability. This paper proposes a numerical calculation using the grid-characteristic method to model elastic waves propagating through soil layers and load-bearing structures from various sources. By solving the direct problem of numerical pulse simulation and varying its location, the values of velocity vector projections and components of the Cauchy stress tensor were obtained at each time step. Two scenarios were examined: the first simulates the impact of noise generated by construction work or nearby traffic, while the second demonstrates how a subway running through an underground tunnel affects multi-story residential buildings. Wave propagation patterns from these sources were visualized in terms of the parameters of interest, enabling a quick and convenient comprehensive analysis of the problem. The analysis of the obtained data will help adjust the timing and types of repair work, identify structural weak points, and develop innovative methods for preserving historical buildings that are cultural heritage sites. Additionally, it will allow for the most economically optimal construction of modern buildings near architectural landmarks, provide an efficient and safe action plan in emergencies, and modernize existing construction technologies to enhance the comfort of residential buildings, office structures, and other socially significant facilities. It will also aid in selecting the most suitable locations for modern high-precision manufacturing plants.

The difference scheme for numerical solution of a time-dependant system of two Schrödinger equations with the operator of a spin-orbit interaction for a two-component spinor wave function is offered on the basis of a split method for a time-dependant Schrödinger equations. The computer simulation of the external neutrons’ wave functions evolution with different values of the full moment projection upon internuclear axis and probabilities of their transfer are executed for head-on collisions of ¹⁸O and ⁵⁸Ni nuclei.

The paper considers the process of flow formation in an outflow of a binary gas mixture through a thin slit into vacuum. An approach to modeling the flows of rarefied gas mixtures in the transient regime is proposed based on the direct solution of the Boltzmann kinetic equation, in which the conservative projection method is used to calculate the collision integrals. Calculation formulas are provided; the calculation procedure is described in detail in relation to the flow of a binary gas mixture. The Lennard–Jones potential is used as an interaction potential of molecules. A software modeling environment has been developed that makes it possible to study the flows of gas mixtures in a transitional regime on systems of cluster architecture. Due to the use of code parallelization technologies, an acceleration of calculations by 50–100 times was obtained. Numerical simulation of a two-dimensional outflow of a binary argon-neon gas mixture from a vessel into vacuum through a thin slit is carried out for various values of the Knudsen number. The graphs of the dependence of gas mixture components output flow on time in the process of establishing the flow are obtained. Non-stationary regions of strong separation of gas mixture components, in which the molecular densities ratio reaches 10 or more, were discovered. The discovered effect can have applications in the problem of gas mixtures separation.

By numerical simulation methods the interaction processes of oscillating soliton (breather) with a 180-degree Neel domain wall in the framework of a (2 + 1)-dimensional supersymmetric O(3) nonlinear sigma model is studied. The purpose of this paper is to investigate nonlinear evolution and stability of a system of interacting localized dynamic and topological solutions. To construct the interaction models, were used a stationary breather and domain wall solutions, where obtained in the framework of the two-dimensional sine-Gordon equation by adding specially selected perturbations to the A3-field vector in the isotopic space of the Bloch sphere. In the absence of an external magnetic field, nonlinear sigma models have formal Lorentz invariance, which allows constructing, in particular, moving solutions and analyses the experimental data of the nonlinear dynamics of an interacting solitons system. In this paper, based on the obtained moving localized solutions, models for incident and head-on collisions of breathers with a domain wall are constructed, where, depending on the dynamic parameters of the system, are observed the collisions and reflections of solitons from each other, a long-range interactions and also the decay of an oscillating soliton into linear perturbation waves. In contrast to the breather solution that has the dynamics of the internal degree of freedom, the energy integral of a topologically stable soliton in the all experiments the preserved with high accuracy. For each type of interaction, the range of values of the velocity of the colliding dynamic and topological solitons is determined as a function of the rotation frequency of the A3-field vector in the isotopic space. Numerical models are constructed on the basis of methods of the theory of finite difference schemes, using the properties of stereographic projection, taking into account the group-theoretical features of constructions of the O(N) class of nonlinear sigma models of field theory. On the perimeter of the two-dimensional modeling area, specially developed boundary conditions are established that absorb linear perturbation waves radiated by interacting soliton fields. Thus, the simulation of the interaction processes of localized solutions in an infinite two-dimensional phase space is carried out. A software module has been developed that allows to carry out a complex analysis of the evolution of interacting solutions of nonlinear sigma models of field theory, taking into account it’s group properties in a two-dimensional pseudo-Euclidean space. The analysis of isospin dynamics, as well the energy density and energy integral of a system of interacting dynamic and topological solitons is carried out.