Temperature deformations of the mirror of a radio telescope antenna

The stress informed state of the mirror of an antenna, with a diameter of 3 m, for a radio interferometer used in space, and located in a temperature field is examined. The mirror represents a parabolic shell, consisting of 19 identical parts. The problem is based on representations of the thermoelasticity of thin shells

Simulation of the short-range order in disordered cubic titanium monoxide TiO1.0

A model of the atomic structure with the short-range order in the vacancy distribution for the disordered cubic phase of titanium monoxide TiO1.0 has been proposed. The effect of the short-range order on the electronic structure and the stability of the compound has been studied by the supercell method within the DFT-GGA approximation with the use of pseudopotentials. It has been established that the appearance of the short-range order considerably decreases the total energy. The decrease in the energy is comparable with the energy gain during the ordering of the vacancies according to the type of monoclinic superstructure Ti5O5 to the long-range order parameter η = 0.7. It has been shown that the discrepancies between the theoretical and experimental electronic spectra of titanium monoxide can be explained by allowance for the short range order. © 2013 Pleiades Publishing, Ltd

Spectral Asymptotics for Perturbed Spherical Schr\"odinger Operators and Applications to Quantum Scattering

We find the high energy asymptotics for the singular Weyl--Titchmarsh m-functions and the associated spectral measures of perturbed spherical Schr\"odinger operators (also known as Bessel operators). We apply this result to establish an improved local Borg-Marchenko theorem for Bessel operators as well as uniqueness theorems for the radial quantum scattering problem with nontrivial angular momentum.Comment: 20 page

Diagnostics of formedness of system of values of future economists in professional preparation process

The article presents the results of the diagnostics of the formation of the value sphere of future economists. The problem of diagnostics of the formedness of the axiosphere of future economic profile specialist is becoming increasingly relevant in the context of modern socio-economic and political conditions. The notion of "value" is considered in the article as a material or spiritual object, which matters for a particular person and causes a valuable relation to it. We define the valuable orientations of the person as a relatively stable orientation of the needs of an individual towards a certain group of values. The purpose of the research is to carry out the diagnostics of the formation of the value sphere of future specialists of the economic profile. Students studying economics on 1-3 courses participated in the study. The methods of conversations, interviews, questionnaires, and observations were used to diagnose the formedness of the value sphere of future specialists in the economic field in the process of carrying out their vocational training. The conducted research testifies to the formedness of certain social image of democratic and totalitarian values of future economic specialists. However, there is a need for further work on clarifying the essence of such socially important values as discipline and law-abidingness and the formation of proper awareness of them by future economists. The development of a methodology for formation of the value sphere of the future specialist in the economic profile is the prospects for further research.peer-reviewe

Influence of a high-power pulsed ion beam on the mechanical properties of corundum ceramics

The mechanical properties of near-surface layers of corundum ceramics treated by high-power pulsed ion beam of carbon are investigated. The samples for investigation were prepared from corundum substrate, which is usually used in microelectronic. The ion treatment was carried out at the TEMP-4M facility under the following conditions: an accelerating voltage of 160-200 keV, the current density in the pulse varied within 15-85 A/cm{2} . It was found that ion irradiation changes the structure and properties of near-surface layers of corundum ceramics. At the same time, melting and erosion of the surface layer takes place. These processes are accompanied by the formation of a network of microcracks. Microcracks are propagated only by the depth of melting layer. The mechanical properties were measured using a NanoTest600 nanohardness testing instrument. It was found that the nanohardness depends of the treatment modes. At a current density of 15A/cm{2} , with an increase treatment dose, the nanohardness of the irradiated surface layer increases in comparison with the initial value before irradiation. At higher current densities, the nanohardness of irradiated ceramics decreases relatively to the initial value before irradiation. The dependences of nanohardness off the irradiation dose in this case have the view of a curves with a minimum at irradiation doses of 2.5∙1014 and 1.3∙1014 cm{-2} , for current densities of 50 and 85 A/cm{2} , respectively

Review of scientific topics for Millimetron space observatory

This paper describes outstanding issues in astrophysics and cosmology that can be solved by astronomical observations in a broad spectral range from far infrared to millimeter wavelengths. The discussed problems related to the formation of stars and planets, galaxies and the interstellar medium, studies of black holes and the development of the cosmological model can be addressed by the planned space observatory Millimetron (the "Spectr-M" project) equipped with a cooled 10-m mirror. Millimetron can operate both as a single-dish telescope and as a part of a space-ground interferometer with very long baseline.Comment: The translation of the original article in Physics Uspekhi http://ufn.ru/ru/articles/2014/12/c

Analyzing the Demand for Educational Services of Higher Education Institutions of Ukraine in the Context of Modern Challenges

The aim of the article is to study the demand for educational services in Ukraine under the influence of economic, political and social factors that are effective in the country. Among the main factors influencing the demand for educational services are the COVID-19 pandemic, the full-scale invasion of the russian federation on the territory of Ukraine and, as a result, migration processes, the destruction of educational infrastructure, changes in the structure of the labor market, budget constraints, reduction of funding at the expense of households, etc. The projected value of the reduction in demand for educational services (number of entrants) by 2025 based on the studied parameters is on average 10%. A correlation and regression analysis was carried out to study the demand for educational services of higher education institutions (HEIs) depending on the main demographic, economic, political and social indicators. According to the analysis of the correlation matrix, the factors that have a high level of closeness of interconnection and a direct impact on the number of entrants to HEIs are the number of school graduates, the number of population aged 16–59 years and the employment rate. Factors such as a decrease in education costs, the COVID-19 pandemic, and the occupation have an inverse impact on the number of entrants. The paper considers the study of the effectiveness of the State regulation of admission to the budget form of education in individual specialties. For this purpose, data on the results of the 2023 admission campaign from the Unified State Electronic Database on Education were used. It is found that in 2023, the highest demand is for specialties related to the social and philological direction (Psychology, Journalism), as well as those that have a well-established importance in terms of prestige and employment (Dentistry, International Relations, specialties in the IT profile, etc.). On the other hand, the lowest demand is for engineering specialties, where the competition is two applications for three budget-funded places. The article uses econometric methods of analysis of digital information, analyzes the influence model between the indicators of the passing score and the general competition. Recommendations are provided on the revision of the policy of admission and competitive selection of students in certain specialties, taking into account the existing established trends in the demand for engineering specialties and taking into account the factor of occupation of the country’s territory and, as a result, changes in the structure of production and needs in the labor market

Deep learning based automatic software defects detection Framework

We present the VulDetect, a source code vulnerability detection system. This system uses deep learning methods to organizate rules for deciding whether a code fragment is vulnerable. This approach is an improvement of the approach proposed in VulDeePecker. The model uses the AST representation of the source code. We compared vulnerability detection results of both systems on the Bitcoin Core project

Abstract kinetic equations with positive collision operators

We consider "forward-backward" parabolic equations in the abstract form $Jd \psi / d x + L \psi = 0$, $0< x < \tau \leq \infty$, where $J$ and $L$ are operators in a Hilbert space $H$ such that $J=J^*=J^{-1}$, $L=L^* \geq 0$, and $\ker L = 0$. The following theorem is proved: if the operator $B=JL$ is similar to a self-adjoint operator, then associated half-range boundary problems have unique solutions. We apply this theorem to corresponding nonhomogeneous equations, to the time-independent Fokker-Plank equation $\mu \frac {\partial \psi}{\partial x} (x,\mu) = b(\mu) \frac {\partial^2 \psi}{\partial \mu^2} (x, \mu)$, $0<x<\tau$, $\mu \in \R$, as well as to other parabolic equations of the "forward-backward" type. The abstract kinetic equation $T d \psi/dx = - A \psi (x) + f(x)$, where $T=T^*$ is injective and $A$ satisfies a certain positivity assumption, is considered also.Comment: 20 pages, LaTeX2e, version 2, references have been added, changes in the introductio