bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermalization of the plasma arising during counter collision of high-energy plasma flows in a longitudinal magnetic field
Authors: Gavrilov V V , Eskov A G , Zhitlukhin A M , Kochnev D M , Pikuz S A , Poznyak I M , Ryazantsev S N , Skobelev I Yu , Toporkov D A , Umrikhin N M 
Published: February 2021

Abstract
This work is devoted to the study of thermalization of plasma created by head-on collisions of high-energy plasma flows in a longitudinal magnetic field of 0.5–2 T. Hydrodynamic flows contained the energy of 200 kJ with velocities from 2 × 107 to 4 × 107 cm/s and ion density from 2 × 1015 to 4 × 1015 cm−3 were created inside the 2MK-200 facility by two electrodynamic plasma accelerators equipped by a system of pulsed gas injection. Nitrogen, neon and their mixtures with hydrogen and deuterium were implemented as working gases. A process of plasma creating was investigated by near-wall magnetic probes situated in different parts of the interaction chamber. Temporal evolution of the plasma electron temperature had been traced by x-ray photodiodes covered by different filters. It was discovered that the plasma electron temperature changed insignificantly during 6–8 μs after it reached the maximum value, which means that it ionization state can be considered as quasi-stationary.
New large-volume detector at the Baksan Neutrino Observatory: Detector prototype
Authors: Ushakov N A , Fazliakhmetov A N , Gangapshev A M , Gavrin V N , Ibragimova T V , Kochkarov M M , Kazalov V V , Kudrin D Yu , Kuzminov V V , Lubsandorzhiev B K , Lukanov A D , Malyshkin Yu M , Novikova G Ya , Petkov V B , Shikhin A A , Sidorenkov A Yu , Veretenkin E P , Voronin D M , Yanovich E A 
Published: February 2021

Abstract
At the Baksan Neutrino Observatory (Institute for Nuclear Research of the Russian Academy of Sciences, Moscow) deployed in the Caucasus mountains, it is proposed to create, at a depth corresponding to about 4700 mwe (meter water equivalent), a large-volume neutrino detector on the basis of a liquid scintillator with a target mass of 10 kt. This article describes the current state of the first stage of the project, namely a prototype detector with a scintillator mass of 0.5 t. The design of the detector, the equipment and methods used are described.
Seismic barriers filled with granular metamaterials: Mathematical models for granular metamaterials
Authors: Kuznetsov S I , Morozov N F , Bratov V , Ilyashenko A 
Published: February 2021

Abstract
The problem of seismic protection from the main types of surface acoustic waves and shear–pressure (SP) evanescent waves emanating from vicinity of an epicenter of an earthquake is discussed. Herein, SP waves represent a kind of the evanescent waves arising at critical angles of incident of bulk shear waves. The proposed seismic protection method utilizes vertical trenches (vertical barriers) filled with the specially constructed granular metamaterials. Some of nonlinear hyperelastic models along with nonlinear and inelastic models are analyzed for applications using granular metamaterials in case of cyclic dynamic loadings that correspond to arrival of the large intensity surface acoustic and evanescent waves. The main attention is paid to arrival of the large intensity Rayleigh, Rayleigh–Lamb and SP waves, as the most frequent waves and the most dangerous waves for engineering structures. Some of the new constitutive equations for metamaterials exhibiting different elastic moduli at tension and compression phases are proposed and discussed.
High performance wave packet molecular dynamics with density functional exchange-correlation term for non-ideal plasma simulations
Authors: Lavrinenko Ya S , Morozov I V , Valuev I A 
Published: February 2021

Abstract
We report on development of the wave packet molecular dynamics (WPMD) with density functional theory (DFT) simulation technique that we proposed earlier for nonideal plasma and warm dense matter simulations. The method is based on the WPMD where the electron exchange-correlation effects are taken into account using the DFT approach. It is aimed at studying simultaneous dynamics of electrons and ions in equilibrium and non-equilibrium conditions for a wide range of temperatures and densities. Compared to classical molecular dynamics and WPMD simulations the method of WPMD-DFT provides more accurate representation of quantum effects such as electron–ion coupling and electron degeneracy. At this stage of the method development we pay a special attention to the performance issues such as acceleration with graphical processing units, the choice of an optimal simulation box size with respect to the boundary conditions, the use of an adaptive mesh for calculation of the exchange-correlation energy, and implementation of our algorithm in the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS). The results for internal energy of equilibrium dense hydrogen plasma are presented for evaluation of the method.
The interaction of laser radiation with strongly coupled plasmas
Authors: Zaporozhets Yu B , Mintsev V B , Reinholz H , Röpke G 
Published: February 2021

Abstract
New results of measurements of s- and p-polarized reflectivity of nonideal plasma at the frequency of the external electromagnetic field ν
las = 2.83 × 1014 s−1, free-electron number density n
e = 3.3 × 1021 cm−3 (Coulomb nonideal plasma parameter Γ = 1.2) and n
e = 5.2 × 1021 cm−3 (Γ = 1.4) are presented. These data are the result of the next stage of study of optics of a warm dense matter. We present a microscopic approach to describe the entire set of experimental data on the optics of strongly correlated plasma.
Electrical conductivity of dilute colloid electrolytes
Authors: Shikin V B , Chikina I 
Published: February 2021

Abstract
We discuss the mechanism of the influence of the multiply-charged colloidal clusters on linear electric transport in diluted polyelectrolytes. The structure of these colloids has well known form. They are effectively neutral and cannot participate in the transfer of charges in the solution. Nevertheless, there is a linear increase in the conductivity of colloidal polyelectrolyte with an increase in the density of colloids. This phenomenon is observed experimentally. It is shown that this happens due to the change of electric field in the polyelectrolyte under the effect of colloidal particle polarization.
Analysis of micro-acceleration requirements in the context of designing a small technological spacecraft
Authors: Anshakov G P , Belousov A I , Sedelnikov A V , Taneeva A S 
Published: February 2021

Abstract
The paper analyzes the design features of a small technological spacecraft justifying the choice of design parameters and modeling the functioning of the spacecraft in terms of micro-acceleration requirements. These requirements are imposed in order to successfully implement gravitationally sensitive technological processes, determine the possibility and feasibility of their implementation and regulate the choice of design parameters, structural layout diagram and executive bodies of the orientation and motion control system of a small technological spacecraft. The experience of designing, creating and operating medium-class technological spacecraft is generalized and analyzed. Common points and differences are identified and discussed. The approaches proposed in the work and the results obtained can be used in the design of small technological spacecraft.
Demonstration sample research impulse of the propulsion system of nanosatellite
Authors: Blinov V N , Kositsin V V , Lukyanchik A I , Ruban V I , Stepen P V , Yachmenev P S 
Published: February 2021

Abstract
The aim of the research is to determine ways to create a pulse corrective propulsion systems of a maneuvering nanosatellite at the early stages of design when forming its design appearance on the basis of experimental and numerical studies of a demonstration sample with a multifunctional flow-through launch chamber and an micro resistojet of a transverse nozzle placement scheme. A pneumohydraulic scheme of a propulsion system with various chokes of a multifunctional flow-through starting chamber has been developed. Experimental and numerical studies of a demonstration sample of a propulsion system confirmed its operability and the possibility of achieving the specified characteristics by changing the interdependent main design parameters in terms of pressure, temperature, specific thrust pulses, duration of operation in various operating modes, and design parameters of a multifunctional flow-through launch chamber. Based on the results of experimental and numerical studies, a 3D model of an improved pulse propulsion system was developed.
The optimal parameters technique for the vertical ground heat exchangers of the geothermal heat pump systems
Authors: Semenov B A , Saponenko D S 
Published: February 2021

Abstract
A scientifically substantiated methodology for determination the optimal parameters of vertical heat exchangers of a underground circuit of the geothermal heat pump systems (GHPS) by the condition of reaching the maximum integral effect or Net Present Value (NPV) is presented. The calculations have confirmed the maximum economic efficiency of the vertical ground heat exchangers can be achieved when observing the optimal values of two defining parameters: the total length of U-shaped heat-receiving pipe and the consumption of the heat carrier passing on it. The optimal values of these parameters are calculated depending on the type and temperature of the ground, the diameter and grade of polyethylene pipes, the initial temperature of the heat carrier at the inlet, tariffs for heat and electricity, specific capital investments in all elements of the ground exchangers, including earthworks, taking into account the real discount rate and a number of additional initial data. The technique allows, to determine the optimal construction and operating parameters of vertical ground heat exchangers under various climatic conditions and types of ground. Also, this technique makes it possible to quantitatively evaluate the maximum achievable economic efficiency of using underground circuit with vertical U-shaped exchangers for the extraction of low-potential ground heat. The use of given technique is necessary for a real assessment of the feasibility of using GHPS as alternative sources of thermal energy in each case.
On the issue of selecting burned materials in rocket vehicle designs
Authors: Trushlyakov V I , Zharikov K I 
Published: February 2021

Abstract
The concept of selecting materials for the design of separable parts of missiles with a property that ensures their rapid disposal by burning after the mission is completed is considered. The characteristics of incinerated materials are presented. The choice of materials based on the proximity of thermal and strength characteristics to existing structural materials used in the production of traditional head fairings is made.
Study the bias field in bilayer film by computer simulation
Authors: Belim S V , Larionov I B 
Published: February 2021

Abstract
Computer modeling of two-layer system from antiferromagnetic and ferromagnetic films is carried out. The Ising model is used. Wolf ′s cluster algorithm is used for calculations. Phase transition temperatures are determined. A state with an ordered antiferromagnetic film and a disordered ferromagnetic film is selected for examination. Dependence the ferromagnetic film magnetization on parameters of antiferromagnetic film is determined. Computer simulation of ferromagnetic film behavior in external magnetic field is performed. The value of the anti-ferromagnetic bias field is determined from the comparison these two experiments. The dependence of the bias field on the exchange integral value at the film boundary is determined.
Research of the influence of optical fibers structure on the spectral characteristics of Mandelstam – Brillouin scattering
Authors: Bogachkov I V , Gorlov N I 
Published: February 2021

Abstract
Influences of structures of optic fibers, fiber types and the dopant concentration, composition, number and thickness of layers on the characteristics of Mandelstam – Brillouin backscattering are discussed. Results of modeling and experimental tests for different types of optic fibers are presented. The comparative analysis of the obtained results is carried out.
About the possibility of using speech recognition technologies in problems of assessing the protection of acoustic information from the leakage throught technical channels
Authors: Ivanov A V , Salimov Sh R 
Published: February 2021

Abstract
This article discusses the possibility of improving the existing instrumental calculation method for assessing the security of meeting rooms by moving from the Pokrovsky formant method to using speech recognition algorithms based on deep neural networks. In our case, it is proposed to use recurrent neural networks that have shown themselves best in terms of information processing with low SNR ratios. Also, using the long-term short-term memory of a recurrent neural network, it is proposed to improve the test signal. In addition, it substantiates the need to take into account the individual characteristics of the room and the possibility of using interference, such as a “speech choir”.
An Approach to Data Transmission Process Modelling in Automated Power Accounting Systems
Authors: Lyubchenko A A , Kopytov E Y , Malyutin A G , Bogdanov A A 
Published: February 2021

Abstract
An accurate accounting of electricity consumption is a relevant task for the improvement of energy efficiency both in industry and in housing and communal services. An important step in solving this task is the deployment of automated metering systems that allow obtaining analytical information required for development and adjustment of energy saving programs. The development of data transmission technologies over cellular networks has led to the widespread use of wireless channels for information exchange in automated energy control and monitoring systems. As both main and reserve communication channels, these systems can use technologies with channel switching (GSM CSD) and packet switching (GPRS). The choice of a particular data transmission technology in this case depends on a number of technical or economic factors. The aim of this work is the development of a conceptual model of the data transmission process in the automated energy consumption monitoring systems with direct connection of meters via GSM CSD and GPRS channels. For modeling the physical layer of the radio channel the model of signal propagation of Okamura-Hata was chosen. Calculation of call blocking probability is based on Erlang-B model. MIR C-01 and CET-4TM have been chosen as electric energy meters. In the work, the conceptual model of data transmission process in the monitoring system with GSM CSD and GPRS channels is offered, being a basis for its further mathematical formalization for the purpose of modelling of an information exchange between elements of the automated energy consumption monitoring system.
The problem of security address resolution protocol
Authors: Stepanov P P , Nikonova G V , Pavlychenko T S , Gil A S 
Published: February 2021

Abstract
This paper examines the conditions for conducting a Man in the middle (MITM) attack in networks using the Address Resolution Protocol (ARP), as well as possible methods for detecting and preventing such attacks. Examples of implementation of denial of service (DoS) attacks in a peer-to-peer network using the ARP protocol are given. An implementation of an ARP spoofing attack in Python and C # using the sharppcap library is presented. Examples of Man-in-the-middle attacks such as DHCP spoofing and ICMP redirection are provided. Describes the techniques of hacking the router and spoofing the MAC address.
Creation of a morphological analyzer based on finite-state techniques for the Uzbek language
Authors: Bakaev I I , Bakaeva R I 
Published: February 2021

Abstract
The article analyzes the existing morphological analyzers related to agglutinative languages. The architecture of the morphological analyzer for the Uzbek language is proposed, the functionality is described using the IDEF0 model, and a finite-state transducer for grammatical and morphological rules is created. Here also described a formal mathematical model for rules morphotactics. Based on the rules of grammar, morphotactics, morphonology, an algorithm was developed using a finite state machine and a transducer.
The dispersion complexes and prognostic tables of allergic triggers “Tree dust” construction
Authors: Goltyapin V V , Kondratieva N A 
Published: February 2021

Abstract
Allergy is one of the most widespread diseases in the world and its epidemic growth over the past 30-40 years is obvious. The results of numerous Russian and foreign epidemiological studies objectively reflect the steady increase in allergic pathology, including pollen allergens being one of the most common allergic triggers. About 15% of the population has the pollen affects allergy, this is one of the most common allergic diseases. Hence, it is important to construct dispersion complexes and prognostic tables to assess the impact of an allergic triggers “birch pollen + alder pollen” combination on the category of observed symptoms (“nasal congestion”, “rash”, “choking”, “itching”). To determine the effect strength on the allergic triggers combination “birch pollen + alder pollen” on symptoms, dispersion complexes were constructed. The calculations were carried out using the STIR computer system with the implementation of a computational algorithm for constructing dispersion complexes and predictive probability tables.
Curriculum optimization algorithm using genetic programming methods
Authors: Guts A K , Senkovskaya A A , Furayeva I I 
Published: February 2021

Abstract
Recently, optimization has become an important aspect of educational process management. The goal of the optimization process is usually reduced to reducing the total amount of the pedagogical load of the university, as well as to the formation of an optimal schedule of training sessions with the existing classroom fund. This article discusses the main aspects of the formation of curricula in order to optimize the educational process. The problem of formation of educational flows is considered with a combination of disciplines of general education and majors. A solution is proposed to optimize the curriculum in order to minimize educational flows and the total teaching load of departments using genetic programming methods.
Study of the main factors affecting the spread of aerosol particles in the atmosphere
Authors: Ravshanov N , Shafiev T R , Daliev Sh 
Published: February 2021

Abstract
To conduct a comprehensive study of the significant factors affecting the transfer and diffusion process of aerosol particles in the atmosphere, a mathematical model, numerical and software tools are developed in the paper. Taking into account the physicomechanical properties of harmful substances discarded from industrial production facilities and the characteristics of soil surface, air velocity, and the substance extinction coefficients. When predicting the concentration of harmful substances in the atmosphere, a key factor that affects the transfer and diffusion of aerosol particles in the atmosphere is the velocity of substance transfer in three directions x, y, z, respectively. The problem posed in the paper is solved by the finite-difference method and the results of numerical calculations on a computer are presented in the form of graphs. It was established that the transfer and diffusion processes of aerosol particles in the atmosphere that play an important role are the rate of air mass formation in the surface layer of the atmosphere; the density and linear size of the aerosol particles emitted into the atmosphere; the terrain, which generates the velocity of air propagation in the atmosphere. It was established by computational experiments that the lower the density and mass of a harmful substance particle, the higher its horizontal velocity and the lower its vertical velocity.
On direct product of algebraic sets over groups
Authors: Shevlyakov A N 
Published: February 2021

Abstract
We study systems of group equations of the form S = S
1 (X) U S
2 (Y), where X, Y are disjoint sets of variables. The central problem is the description of the radical Rad(S) in terms of the systems S

i
. We prove that Rad(S) may contain equations which are not derived from equations from Rad(S

i
). Systems of equations are considered in the following classes of groups: abelian, free and 2-step nilpotent groups.
Numerical research of probabilistic characteristics of quality by the piece the component of mix with increase in number of doses given by the batcher
Authors: Evseev A V 
Published: February 2021

Abstract
In work it is carried out the mathematical analysis of these pilot studies of the automatic conveyor mixer (non-mixer) and drum dozers for receiving mix of single elements of the components having similar standard overall dimensions but differing in internal properties at effective end use. The relevance and novelty of development are shown on the example of receiving the general party of composite product from small similar parties, at the determined forming of its uniformity, with the set qualitative and quantitative characteristics from single heterogeneous components. The analysis of influence of ratios of components in synthesizable mix on its quality is carried out. The main evaluation criterion was the quantity of doses of components at the same time given by batchers and its influence on final parameters of the received mixes.
Two algorithms for numerical modeling of thermal decay of a metastable state
Authors: Chushnyakova M V , Gontchar I I , Khmyrova N A 
Published: February 2021

Abstract
We compare two numerical algorithms for the computer modeling of the thermal decay process (Kramers problem) solving the stochastic (Langevin) equations for the generalized coordinate and its conjugate momentum. These are known in the literature (i) the ALGO algorithm including in the fluctuation part the terms up to τ3/2 (t is the time step of the numerical modeling) and (ii) the Euler-Maruyama algorithm including in the fluctuation part only the terms proportional to τ1/2. We concentrate on the quasistationary decay rate and transient time. The ALGO algorithm appears to be more efficient, however, the optimal size of the time step has a strong and non-trivial dependence upon the dissipation strength and governing parameter.
The experience of magnets manufacturing from metal powder using a laser
Authors: Zhukov A S , Barakhtin B K , Bobyr V V , Kuznetsov P A , Shakirov I V 
Published: February 2021

Abstract
The structure of hard magnetic and soft magnetic alloys manufactured on a RussianSLM FACTORY init by selective laser melting (SLM) from a spherical powder less than 80 μm in size has been studied. The powder is made by melt atomization from ingots. At various scanning speeds and laser power, additive samples were manufactured to study the structure, magnetic parameters, and also fractal analysis. According to the research results, recommendations were given on changing the melting modes and conducting thermal post-processing of materials. By constructing a hysteresis loop, data were obtained indicating the achievement of magnetic characteristics in additive samples that are close in magnitude to magnets of traditional founding technology. Prototypes of complex-shaped additive magnets have been made.