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In this theoretical study, we investigate the effect of electron correlations on the electronic structure and magnetic properties of the full Heusler alloy Mn2NiAl in the framework of first-principles calculations. We investigate the electron correlation effect as employed within hybrid functional (HSE) and also within the DFT+U method with varied values of parameters between 0.9 and 6 eV. The XA-crystal structure was investigated with antiferromagnetic orderings of the magnetic moments of the manganese. It was found that with a growth of the Coulomb interaction parameter, the manganese ions magnetic moment increases, and it reaches the value of 4.15–4.46 μB per Mn. In addition, the total magnetic moment decreases because of the AFM ordering of the Mn ions and a small magnetic moment of Ni. The calculated total magnetic value agrees well with recent experiments demonstrating a low value of magnetization. This experimental value is most closely reproduced for the moderate values of the Coulomb parameter, also calculated in constrained LDA, while previous DFT studies substantially overestimated this value. It is also worth noticing that for all values of the Coulomb interaction parameter, this compound remains metallic in its electronic structure in agreement with transport measurements.

Research results of damage and failure of unidirectional laminate packages under tension are presented. A study of the kinetics of damage and failure of the laminate structure is carried out by means of acoustic emission (AE) and synchronous video recording. The conformity between failure proceses occurring on the microscopic, mesoscopic and macroscopic scale levels and the recorded AE events including their energy parameters, shape and spectrum is established. The structural–phenomenological approach implemented by dividing the AE data array into energy clusters allows analyzing the degree of damage and failure of the material employing new criteria parameters, namely the registration activity and the weight content of the location AE events in the clusters of the lower, middle and upper energy levels.

The purpose of the work is a formalized description of the method determining numerical expression of the danger from actions potentially implemented by an information security violator. The implementation of such actions may lead to a disruption of the ordered functioning of multilevel distributed automated process control systems, which indicates the importance of developing new adequate solutions for predicting attacks consequences. The analysis of the largest destructive effects on information security systems of critical objects is carried out. The most common methods of obtaining the value of the hazard quotient of information security violators' destructive actions are considered. Based on the known methods for determining the possible damage from attacks implemented by a potential information security violator, a new, previously undetected in open sources method for determining the hazard quotient of destructive actions of an information security violator has been proposed. In order to carry out experimental calculations by the proposed method, the authors developed the required software. The calculations results are presented and indicate the possibility of using the proposed method for modeling threats and information security violators when designing an information security system for automated process control systems.

Currently, transuranic elements are a serious problem. They are formed in spent nuclear fuel as a result of the operation of reactors. These elements have a sufficiently high radioactivity and a huge half-life, thus they remain dangerous for a very long time and must be burned out on specialized reactors. However, not all of them can be classified exclusively as waste. Am-241, which has a low heat release due to its alpha decay, can be used as a radionuclide source for RTGs. However, this nuclide can maintain a fission chain reaction and emits gamma rays as a result of decay. The article investigates some properties of possible devices, as well as an assessment of the radiation protection for such devices.

The structural-phenomenological concept (SPС) and model of the evolution of fracture in a composite material are considered. The relationship is explored between the bearing capacity and the kinetics of redistributing the weight composition of micro-, meso-, and macroscale damage during the loading process. Monitoring the change in the cumulative amount of partial damage values in the structure of a material at different scales in the loading mode and comparing these values with the threshold makes it possible to control the actual state of the load-bearing capacity of the product. The correspondence between the surfaces of micro-, meso-, and macrofractures of bonds in a structural material and energy parameters of the recorded acoustic emission pulses is theoretically substantiated and experimentally confirmed. The acoustic emission pulses are formed in the field of descriptors of the relative energy (Ep) and maximum amplitude (um) of the domains of the lower (L), middle (M), and upper (U) levels. The boundaries of these energy levels are as follows: Ep < 85 dB, um < 55 dB; Ep = 85 –115 dB, um = 55–80 dB; Ep > of 115 dB, um > 80 dB, respectively. An algorithm and software are developed to control the dynamics of the redistribution of the parameters of partial activity (Ni) and weight composition (Wi) of location pulses in energy domains that characterize the kinetics of micro-, meso-, and macrodamage in situ for breaking the structural bonds of the product in the loading mode. By comparing the current values of the most informative parameters WL and WM with the threshold values [WL] and [WM] corresponding to the product entering the stage of material failure, we can control the actual level of the bearing capacity of the structure. The developed concept, algorithm, and software are used to assess the load-bearing capacity of a panel with the frame structure during compression tests in the loading mode.

Here we present the current state of the technical design of the SPHERE project’s new detector. The SPHERE project is aimed at primary cosmic ray studies in the 1–1000 PeV energy range using the reflected Cherenkov light method. The concept of a drone mounted detector with a photosensitive camera based on silicon photomultipliers is discussed. The design details of a small scale prototype of this detector is presented.

Paper contains the first results on the development of a SPHERE-3 telescope for the primary cosmic ray studies in 1–1000 PeV energy range using reflected and direct Cherenkov light generated by extensive air showers. It also sheds some light on the development of our new approach to the design of the new telescope.

The paper presents the analysis of the results of plastic deformation zones obtained by the ball indentation into the surface of a non-magnetic metal plate using the amplitude-sensitive eddy current method. Calculation and experimental methods were used in the research. A two-dimensional finite-element model of an eddy current probe installed above a local plastically deformed zone on the metal plate surface was developed. The finite-element modelling of the electromagnetic field of eddy currents induced in the aluminium plate during multi-frequency excitation was made. It is found that the amplitude-sensitive eddy current method is appropriate not only to estimate the plastic deformation zone propagation depth, but also to detect a zone with the maximum stress values beneath the indent (hydrostatic core zone). An experimental verification of the proposed model was done. The specific zones in the deformed metal beneath the indent were detected by the eddy current method and the hydrostatic core size was evaluated.

Further development of the way of studying primary cosmic rays by detecting the reflected extensive air shower Cherenkov light is planned, based on the successful implementation of the SPHERE-2 aerostat experiment. The possibility of simultaneously detecting direct and reflected Cherenkov light from extensive air showers is demonstrated. Prospects for creating a new SPHERE-3 detector are discussed and the first results from modeling are presented.

A structural-phenomenological concept of monitoring the residual strength of composite materials is proposed. The structural-phenomenological concept was developed taking into account the kinetics of damage and destruction of polymer composite material (PCM) at the micro-, meso-, and macroscale levels, which generate acoustic emission pulses (AE) recorded by the receiving transducers of the antenna array. A correspondence between the ongoing destruction of the composite material structure at the micro-, meso-, and macroscale level and the AE pulses recorded at the same time and their weight content provides the possibility of monitoring of the damage kinetics in the loading mode at all structural levels and, consequently, the possibility of control of the residual strength of the product. An algorithm and software have been developed that made it possible to divide the recorded AE signals into clusters of lower, middle, and upper energy levels corresponding to micro-, meso-, and macroscale disruptions of the structure of a composite material and calculate the AE activity and the weight content of location pulses in energy clusters, thus displaying the dynamics of their changes every second. Comparison of the current values of the most informative parameters of the weight content of location pulses in energy clusters with the threshold values recorded during the destruction of the material provides monitoring of the residual strength of the product in the loading mode. The validity of the developed concept, algorithm and software was proved during tests of elementary and structurally similar samples of PCM under different loading conditions. An example of using the developed technique for revealing the areas of the most intense damage accumulation in a MS-21 fuselage panel at a stepwise increase in the compressive load is presented. In addition to the possibility of identification of the area of intense accumulation of damage and failure of the structure of the composite material, the structural-phenomenological concept of the AE diagnostics provides also the possibility of tracing the damage kinetics at different scale-structural levels, controlling the level of the residual strength of the panel upon the stepwise compression.