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In this article, the effect of heat treatment on the phase composition and structural state of welded joints of an experimental highly-doped titanium alloy, made by argon-arc and electron-beam welding, was investigated. As a result of the heat treatment of welded joints at a temperature of 690 ° C, the structure of the near-seam zone is stabilized. However, in order to fully restore the plasticity of the welded joint with the formation of alpha-phase globules of a simple structure in the structure of the near-seam zone, a higher heat treatment temperature is required.

The results of the work of the NRC “Kurchatov Institute” – CRISM “Prometey” on the creation of titanium alloys for deep-sea marine equipment, vehicles and submersibles are presented. The paper considers development of titanium alloys with a yield strength of more than 1000 MPa.

This article investigates the change in the phase composition and structural state during the thermal cycle of welding a high-alloyed titanium alloy. It is shown that structural-phase transformations in the welded joint occurring under the influence of the thermal and deformation cycle of welding lead to the formation of metastable phases, and its subsequent decomposition can lead to ductility losses. To bring the metal of the welded joint to an equilibrium state, stabilizing annealing is required.

The microstructure and mechanical properties of joints made of alloy 6082-T6 obtained by friction stir welding (FST) are investigated. Welded joints have a pronounced heterogeneity in microstructur...

The adsorption of Cd and Te on the surface of a CdTe crystal is studied in situ using a mass spectrometer in the temperature range of 500−700 K and at an incident flux intensity of VCd = 10–2−2 single layers per second, SL/s, and VTe = 0.5−5 SL/s. Computer programs for controlling the experiment and processing the obtained information are developed. The growth parameters are in good agreement with the proposed model of adsorption. The activation energies of the “evaporation” (transition of atoms from the crystal to the adsorption layer) and desorption of Cd atoms and Te2 molecules are 2 and 0.5 eV and 0.59 eV, respectively. It is established that the dependence of the growth rate on the Te2 flux at a constant Cd flux is linear over a wide range, while the dependence of the growth rate on the Cd flux at a constant Te2 flux is nonlinear and reaches saturation. The growth parameters depend on the structural features of the crystal surface (roughness, polycrystallinity, and mosaicity) accompanying film growth at large deviations from equilibrium.

We consider dynamic inverse problems for a dynamical system associated with a finite Jacobi matrix and for a system describing propagation of waves in a finite Krein–Stieltjes string. We offer three methods of recovering unknown parameters: entries of a Jacobi matrix in the first problem and point masses and distances between them in the second, from dynamic Dirichlet-to-Neumann operators. We also answer a question on a characterization of dynamic inverse data for these two problems.

A dynamic inverse problem for a dynamical system that describes the propagation of waves in a Krein string is considered. The problem is reduced to an integral equation, and an important special case is considered where the string density is determined by a finite number of point masses distributed over the interval. An equation of Krein type, with the help of which the string density is restored, is derived. The approximation of constant density by point masses uniformly distributed over the interval and the effect of the appearance of a finite wave propagation velocity in the dynamical system are also studied.

The welding properties of argon-arc and electron-beam welding of pseudo-β-titanium alloy of VST 5553 grade are investigated. It is necessary to apply heat treatment after welding to improve the mechanical properties of welded joints.

Some indicators that determine the trends in the aquaculture development in the world, such as the number of employed and the volume of aquaculture production by continent have been considered as well as a forecast for the development of the industry in comparison with industrial fisheries and an analysis of the volume and growth rate of aquaculture production in some foreign countries have been given. The essence of regional protectionism in aquaculture has been revealed, its relationship with government programs and strategies for the aquaculture development in the country has been determined, the development and implementation of which are based on the formation of strategic competitive advantages in the global market and ensuring national food security. An analysis of the level of food security by the countries of the world allowed the authors to identify some foreign countries from different regions of the world with various forms of government and to characterize the implementation of regional protectionism in aquaculture in these countries. As a result of evaluating the implementation of regional protectionism in some foreign countries, the authors concluded that the volume of aquaculture production is directly dependent on the effectiveness of protectionism measures in the regions (provinces, states and other domestic territorial entities). In addition, the efforts made by Central authorities to support and develop aquaculture in the country, expressed in the development and active implementation of state programs and strategies, delegation of authority to the regional level, as well as support for the development of informal industry institutions, are a significant factor not only in ensuring food security of the state, but also in increasing the effectiveness of regional protectionism measures in aquaculture.

The nonlinear dynamics of the 197Au31+ ion beam in the booster has been studied with the MAD-X program. The numerical computation of the dynamic aperture for the DFO-magnetic lattice of the booster is presented. Resonances of second and third order are taken into account. An analysis of the betatron oscillation frequency spread is carried out. This paper shows that the use of multipole correctors allows one to get beams with the required parameters.

The NICA accelerator complex will consist of two injector chains, a new 600 MeV/u superconducting booster synchrotron, the existing superconducting synchrotron—Nuclotron, and the new superconducting collider that has two storage rings each of about 503 m in circumference. The influence of the fringe fields and misalignments of the structure magnets, the field imperfections and natural chromaticity should be corrected by the correction system. The main parameters, arrangements and the field calculations of the corrector magnets are presented.

The welding properties of argon-arc and electron-beam welding of titanium pseudo-β-alloy of VST 5553 grade are investigated. It is shown that to increase the level of mechanical properties of welded joints, it is necessary to apply heat treatment after welding.

Despite the low invasiveness of percutaneous nephrolithotripsy, this surgery is not without complications. One of the most important stages of the operation, on which depends not only the success of the patient completely getting rid of calculus, but the likelihood of complications, is the puncture of the pelvic-pelvic system.Determination of the effectiveness and security of the new less-traumatic puncture needle MG under experimental conditions.A series of pork kidney punctures with a new less-traumatic needle MG and standard Chiba and Troakar needles (Coloplast A/S, Denmark) were performed under experimental conditions, followed by a comparative morphological assessment. The staining of the slides was performed with hematoxylin and eosin. For the purpose of additional assessment of the structures of the kidney punctured with a low-traumatic MG needle, a morphological assessment of the parenchyma stained with picrofuchsin according to Van Gieson was performed.On parenchymal slides with punctures with Chiba and Trocar needles, the passage places with multiple large fragments of desquamated (damaged) epithelium are visualized. On preparations of the parenchyma punctured with a less-traumatic needle MG, the place of passage of the needle is presented with clear contours. The damaged epithelium in the lumen of the formed defect is practically absent. With additional staining according to Van Gieson (magnification x200), the integrity of the full-blooded vessel adjacent to the limited focus of the needle MG was visualized. Output. The new less-traumatic puncture needle MG is an innovative development in urology. The design of the needle with an atraumatic mandrel-bulb atraumatic mandrel-bulb on a spring basis made it possible to significantly reduce the trauma to the structures of the kidney and perirenal tissues due to the bougienage effect.

A comprehensive study is made of the properties of samples of BiFe1−xMnxO3 (0.05 ≤ x ≤ 0.15) solid solutions synthesized using the sol-gel technique. Stabilization of the main phase, a reduction in the average granule size, and an increase in the dielectric constant are observed upon an increase in concentration x. The presence of Mn ions in BiFe1−xMnxO3 solid solutions results in semiconductor-type conductivity and the emergence of magnetic ordering at 605 K (х = 0.05) and 550 K (х = 0.15).

—The results of a statistical and harmonic analysis of the magnetic measurement data of structural elements (dipole magnets) of the Nuclotron Booster at an injection and extraction current are presented.

The problem of reconstruction of the Cauchy data for the wave equation in ℝ1 from the measurements of its solution on the boundary of a finite interval is considered. This is a one-dimensional model for the multidimensional problem of photoacoustics, which was studied previously. The method was adapted and simplified for the one-dimensional situation. The results of numerical testing to see the rate of convergence and the stability of the procedure are given. Some hints are also given on how the procedure of reconstruction can be simplified in the 2d and 3d cases.

We consider a dynamic inverse problem for a dynamical system describing the propagation of waves in a Krein–Stieltjes string. We offer three methods of recovering the string, that is point masses and distances between them, from the dynamic Dirichlet-to-Neumann operator.

The inverse dynamic problem for the wave equation with a potential on a real line is considered. The forward initial-boundary value problem is set up with the help of boundary triplets. As an inverse data, an analog of the response operator (dynamic Dirichlet-to-Neumann map) is used. Equations of the inverse problem are derived; also, a relationship between the dynamic inverse problem and the spectral inverse problem from a matrix-valued measure is pointed out.

Magnetic hysteresis loops obtained in the fields from 0 to ±2.5 kOe and dielectric permittivity e (at 1 kHz, 1 MHz, and 8.3 GHz) of (1 – x)BiFeO3–xYMnO3 composite multiferroics (0 ≤ x ≤ 0.5) were studied. Ceramic samples of solid solutions were made by the nitrate process. Compositions (1 – x)BiFeO3–xYMnO3 with 0.1 ≤ x ≤ 0.5 were found to be soft ferromagnetic materials sensitive to weak magnetic fields. Coercive field Hc is about 20–32 Oe for these samples. The maximal magnetization was observed in the sample having x = 0.35. For the samples with 0 ≤ x ≤ 0.4 at T = 300 K, the permittivity was e ~ 17.6–248.6 at the frequency of 1 kHz, 7.8–63.2 at 1 MHz, and 4 ± 0.3 at 8.3 GHz.

The object of consideration is asynchronous address systems using code division of subscribers. The subject of the analysis is noise immunity of quasi-orthogonal signal ensembles based on a subset of M-sequences, allowing joint processing of code sequences. The purpose of the analysis is to determine the noise immunity characteristics of system using M-sequences subset that have the stated properties of joint processing. The solution is based on the principles and mathematical models developed by authors: the principle of the fast conversions in Galois fields, algebraic model of representation and structure of fast delay acquisition devices for a subclass of the sequences as well as on the simulation of the corresponding devices. This article is devoted to the study of the correlation properties of signal ensembles possessing the property of joint fast processing, as well as to the finding of the noise immunity characteristics of the corresponding signal receiving and processing devices. It is shown that the considered subset of code sequences, allowing joint fast processing, can be used in various scenarios, including in the scenarios of "distinguish-measure" objects, simultaneously using different code features from the ensemble under consideration. In this case, the considered devices are resistant to changes in the signal structure within the established ensemble. The proposed variants of the search scheme perform reception and primary processing of code sequences in real time, which favorably distinguishes them from known schemes that perform fast transformations by other methods. The results of the work will be useful to specialists involved in the design of asynchronous-address systems using complex signals based on code sequences with a large base.

We consider the dynamic problem for the discrete system with discrete time associated with (finite and semi-infinite) Jacobi matrices. The aim of the paper is to associate the special Hilbert spaces of functions, playing an important role in the inverse spectral theory, with these systems by making use of the method previously developed by the authors.

В работе показана сущность государственно-частного партнерства (ГЧП), его особенности, типология и правовые основания функционирования в Российской Федерации. Приведен анализ данных о численности соглашений всех форм ГЧП, объемах инвестиционных обязательств и роли ГЧП в экономике страны. Выявлены сферы наибольшего развития механизма ГЧП в стране. Вскрыта проблематика деятельности отечественного лесного комплекса, показана актуальность привлечения для разрешения этих проблем механизма ГЧП и необходимость комплексного эффективного развития и использования лесов, в частности создания лесных селекционно-семеноводческих центров по выращиванию посадочного материала для лесовосстановления, развития лесной инфраструктуры, организации глубоко продуманной системы вырубки и учета вырубленной древесины, ее транспортировки для переработки, стимулирования внутренней глубокой переработки лесоматериалов, популяризации и налаживания экотуризма в лесах

In this paper, using the exponential Queuing networks (QN) apparatus, the problem of finding the maximum fault tolerance distributed information processing systems (IPS) implemented on the basis of a two-level and three-level client-server architecture is formulated and solved. The method of finding the average response time for all user requests is presented. It takes into account the impact of fault tolerance of individual servers of such a system. The problem determining the fault tolerance indicators of distributed IPS was reduced to the problem determining the stationary probabilities of QN states. The paper also presents an iterative algorithm for solving this problem. At the conceptual level, the presented models can be used to obtain reliability characteristics of integrated automated control systems (IACS) in the electric power industry

In this paper, we consider the application of stochastic Queuing networks (QN) to solve a practical problem related to a more rational organization of the computing process in information systems of the electric power industry. Exact methods of stochastic QN analysis are presented by the closed exponential QN analysis method, approximated by the decomposition approximation method, the average knowledge analysis method, and simulation modeling. The simulation method used an approach based on a combination of agent and process modeling. This approach was applied to obtain an adequate mathematical model of the functioning of a distributed IPS with an input stream that has self-similarity properties. The results of numerical solution of practical problems are presented.

The paper presents a semi-empirical wide-range equation of state (EOS) for platinum with account for melting, evaporation, and ionization. The equation is based on a wide spectrum of experimental and calculation data. Parameters for the EOS were adjusted using a genetic algorithm which proved to perform well for optimizations in big data processing. In the regions where no experimental data were available, we used results of first-principles and average-atom model calculations. The EOS was used to calculate the melting curve of platinum to pressures above 1 TPa, sound velocities along the Hugoniot curve, parameters of melting under shock compression, and parameters of the critical point. An improved model is proposed for the shear modulus in (V, T) coordinates and its variation along the shock adiabat is calculated.

The object of consideration is wireless networks of the 802.11 standard, also modeling options for the intruder active impact on the physical environment to evaluate the effectiveness of information interaction in the presence of signal-like interference. The subject of the study is the development of software and hardware solutions based on the USRP architecture and LabVIEW software environment for modeling the intruder active impact at the physical level, aimed at destroying or reducing the information interaction effectiveness of wireless network clients. The purpose of the study is to substantiate the possibility and evaluate the effectiveness of the USRP devices and LabVIEW software environment for prototyping specialized hardware and software devices use. The solutions are based on the documented characteristics of National Instruments Corporation's USRP devices, a description of LabVIEW virtual devices that solve particular problems of physical monitoring, but mainly on the results of authors experimental studies, as well as testing these results and technical solutions in the educational process. The article is devoted to substantiating the relevance of modeling an aggressive electromagnetic environment, building specialized software and hardware devices based on the USRP architecture, testing a number of scenarios for generating signal-like interference with an evaluation of their effectiveness.

The object of consideration is systems of cognitive radio, area and cases of their application in the tasks of technical support of special information needs, in particular, for deep or operational monitoring of the radio broadcasting channels content. The subject of research is the development of software and hardware solutions for special tasks of cognitive radio based on SDR technology, USRP architecture and LabVIEW software environment. The purpose of the research is to formulate and justify the tasks of information service, to justify the possibility and evaluate the effectiveness of SDR technology, USRP architecture and LabVIEW software environment using for specialized hardware and software devices prototyping. The decisions are based on the results of similar studies published in periodicals and on the Internet, but mainly on the results of experimental research by the authors, as well as testing of these results and technical solutions in the educational process. The article is devoted to the search, substantiation of relevance and the formulation of a number of information service tasks using cognitive radio technology, the problems analysis of implementing the corresponding devices based on the prototyping paradigm, the evaluation of these devices using performance to solve a number of information service problems, and the experimental verification of the functionality and quality of the developed prototypes.

Background: Brugada syndrome is a hereditary disease with genetic and phenotypic variability characterized by a high risk for arrhythmia and sudden cardiac death. It is assumed that modifying genetic factors contribute to the variability of the phenotype. Mitochondrial DNA (mtDNA) polymorphism can be considered among such factors, since mitochondrial dysfunction, including that associated with mtDNA variants, can have an arrhythmogenic effect. Aim: To study possible association between mtDNA polymorphism with the phenotype in the Russian patients with Brugada syndrome. Materials and methods: We have studied mtDNA polymorphism in 36 Russian probands with Brugada syndrome. Common “European” haplogroups of mtDNA were assigned using sequencing of the hypervariable segment 1 in mtDNA D-loop. Results: In the study sample, the frequencies of the mtDNA haplogroups generally correspond to the distribution common for the Russian populations, except the J haplogroup, which was not found in the studied probands. The results contradict with previously published data on the J and T haplogroups as risk factors for Brugada syndrome manifestation. Conclusion: The study did not reveal the role of mtDNA polymorphism (J and T haplogroups) in the formation of the Brugada syndrome phenotype.

We propose a method of definition of a solution of the semi-infinite Toda lattice for a wide class of unbounded initial data. For this purpose we describe the evolution of moments of the spectral measure of semi-infinite Jacobi operator associated with the Toda lattice.

The object of consideration is async-address systems using code division of subscribers. The subject of the analysis is quasi-orthogonal ensembles of signals based on code sequences that have normalized characteristics of cross-correlation functions (CCF) and provide reliable separation of subscribers (objects) when exposed to imitation and signal-like interference. The purpose of the analysis is to create a model and methodology for construction a set of the best code sequences ensembles having the ability to quickly change the instance of the set to counter imitation and signal-like interference. The solution is based on algebraic models of code sequences and their CCF representation. The article proposes a comprehensive technique to construct signal ensembles set having normalized characteristics of the CCF. The quality of the primary ensemble of code sequences is ensured by the procedure for calculating the CCF optimized in the number of look over options. Optimization is based on the basic properties of the Galois field, in particular, on the Galois fields’ isomorphism property. It provides a significant reduction in calculations when choosing the primary ensemble of code sequences with the specified properties of the CCF. The very choice of the best (largest in size) code sequences ensemble relies on the solution of one of the classical combinatorics problems – searching for maximal clique on a graph. The construction of signals ensembles set having normalized characteristics of the CCF is ensured by the use of special combinatorial procedures and algorithms based on the multiplicative properties of Galois fields. An analysis of the effectiveness of known and proven procedures searching for maximal clique is also performed in this article. The work results will be useful in the design of infocommunication systems using complex signals with a large base and variable structure to provide protection from signal structure research and the effects of imitation and signal-like interference

We consider the problem of reconstruction of the Cauchy data for the wave equation in ℝ 3 {\mathbb{R}^{3}} and ℝ 2 {\mathbb{R}^{2}} by the measurements of its solution on the boundary of the unit ball.

The object of consideration is radio systems using special correlation properties of code sequences for the simultaneous execution of various information functions, in particular, measuring the motion parameters of aerospace objects group and transmitting a variety of information. The subject of the analysis are procedures for the construction and processing of encoded signals, ensuring the effective compositing of information functions. The purpose of the analysis - identification of classes and characterization of code sequences, devices for their construction and processing, capable of compositing information functions and having the property of adaptation to the rapid change in the code sequences structure. The solution is based on the principles and mathematical models developed by the authors: the principle of fast transformations in Galois fields, an algebraic representation model, and the structure of fast delay acquisition devices for a subclass of sequences. The article is devoted to the search and evaluation of encoding methods characteristics, the method of compositing information functions with the minimum mutual influence of signal processing processes on each other, identifying encoding and decoding rules that can quickly adapt signal processing devices to changing encoding parameters. The results of the work will be useful to developers of various information and communication systems that are resistant to signal-like noises.

The quality of booster closed-orbit correction is estimated. The distribution of the maximum orbit distortion in both directions and the results of numerical simulation using the singular value decomposition method are given. The estimation of closed-orbit distortion with the worst correction quality is given.

The paper considers software for the simulation and analysis of transverse dynamics of charged particle beams in synchrotrons and beam lines. It calculates the transverse beam dynamics in synchrotrons and beam lines based on the linear model, the structural functions of synchrotrons and beam lines, the beam acceptance and emittance, and the orbit correction. The software is capable of calculating the orbit-correction quality distributions and reconstructing the transport matrix parameters from the response matrices.

Problems connected with the Nuclotron virtual simulation model within MADX are considered. The main objective of the study is a more precise specification of the exiting accelerator model, so that the numerical results obtained using MADX are as close as possible to the experimental data obtained in the last Nuclotron runs. The groups of parameters that bring theoretical calculations closer to the experimental data are found via analyzing the impact of the model characteristics on the numerical results.

One of the modern antibacterial strategies to control various infectious pathogens in agriculture, veterinary medicine, and the food industry is the use of bacteriocins, which are potent antimicrobial peptides produced by almost all species of bacteria. The wide distribution of antibiotic-resistant bacteria, as well as the increasing awareness of the importance of the normal human biocenosis for health, necessitates the study of this new class of antimicrobial agents, whose application is recognized an alternative strategy for the treatment of infectious diseases. Among diverse marine organisms, bacteria are considered the most numerous. They are a promising source of bacteriocins, which play an important role in regulating competitive interactions in marine microbial systems. In the marine environment, with its high competition for space and resources, bacteria produce more potent bacteriocins than those isolated from other ecosystems. The scientific substantiation of the relevance of the research on the biological properties of these peptides is associated with the prospect of industrial cultivation of their producers in maricultures, as well as with the use of bacteriocins for medical and veterinary purposes.

We derive special representation for Weyl functions for finite and semi-infinite Jacobi matrices with bounded entries based on a relationship between spectral problem for Jacobi matrices and initial-boundary value problem for auxiliary dynamical systems with the discrete time for Jacobi matrices.