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This paper presents an efficient hybrid asynchronous three-dimensional (3D) perfectly matched layer (PML) for modeling unbounded domains. The proposed unsplit explicit or implicit 3D PML formulation is implemented in the framework of a heterogeneous asynchronous time integrator. It is fully versatile in terms of time integrators and time step sizes according to partitions while conserving classical finite element formulations in the elastic domain without complex-valued stretched coordinates. Examples of a semi-infinite bar, Lamb’s test, and a soil–structure interaction problem with PML-truncated semi-infinite heterogeneous media are investigated to illustrate the efficiency of the proposed PML in terms of accuracy and CPU time.

The recent devastating earthquake of Mw7.8 occurred on February 6, 20223 in the Kahramanmaraş region having extreme intensity (XI) on the modified Mercalli scale (MMS) caused the death of more than 52,800 people in Turkey and Syria, as well as severe damages to the infrastructure. The appearance of an unusually strong delta-like S-wave pulse in the seismogram of the main shock and its consequences are analysed, and possible measures to mitigate the possible future high intensity earthquakes are discussed.

Farm animals provide about 30% of humanity’s food requirements [1]. The world’s population’s demand for animal products is expected to keep growing. New technologies in animal husbandry can make it possible to meet this demand and to reduce its impact on the environment. Genomic selection plays a key role in this process as a promising and safe method for improving genetic qualities of farm animals. Before the widespread of genomic selection, high cost of genotyping was the main factor holding back an improvement of animal farming. However, today, the bottleneck in genomic selection is a limited amount of high-quality phenotypic data, which is still either difficult or too costly to obtain [2]. New technologies in animal phenotyping become of special attention. The current paper reviews the next-generation technologies in animal phenotyping and revels the main challenges limiting its widespread in the example of dairy cattle.

The system of technical operation (TO) of on-board equipment or avionics of aircraft (AC) as an object of research is a set of objects and means of technical operation, maintenance and repair programs, as well as personnel performing procedures and organizing the processes of TO. The quality of the TO system is manifested in the TO process - a set of processes of intended use, operational control, maintenance, restoration and repair. The TO process, as a process of changing the TO states, can be considered as a controlled random process, determined on the set of operation states by probabilistic characteristics. The quality of the TO system is characterized by a set of properties that determine its ability to satisfy with the maximum economic efficiency the needs of the TO system of the aircraft, while ensuring the required levels of reliability and readiness of the avionics for operation. That is, the TO system has all the features inherent in complex technical systems - a hierarchical ramified structure, subordination of goals and restrictions, wide interrelationships in the process of functioning. The main research apparatus in solving problems of optimization of processes and synthesis of TO systems is the apparatus of the theory of mathematical modeling of complex technical systems, based on a system approach, the integration of analytical and simulation modeling. The article solves the problem of determining the values of the parameters of the TO system such that the costs of the system during the TO process reach a minimum when all the required tasks are completed and all restrictions on the system’s own parameters and indicators of its technical efficiency are met.

Structural synthesis creates a structural scheme according to the given structural characteristics - the degree of abnormality of the structure S and the degree of its irrationality s. Structural scheme is created at the first stage of synthesis, containing only rotational kinematic pairs and corresponds to a given degree of abnormality, which is ensured by the ratio of structural units – plus monads, minus monads and null monads. At the second stage, the independence of structural characteristics makes it possible to bring the obtained scheme to a given degree of irrationality by downgrading the class of kinematic pairs. The proposed algorithm makes it possible to synthesize structural schemes of both normal structure and adaptive (with redundant motions), as well as indifferent (with redundant links). Monadic approach to structure research allows to formalize the structural features of the circuit and to create a knowledge base for automated design of structural circuits with given structural properties.

A mathematical model for analyzing Lamb waves propagating in stratified media with arbitrary elastic anisotropy is worked out. The model incorporates a combined Fundamental Matrix (FM) and Modified Transfer Matrix (MTM) methods. Multilayered unbounded plates with different types of boundary conditions imposed on the outer surfaces are considered. Closed form fundamental matrices and secular equations for dispersion relations are derived.

Degeneracy of the linear dispersion wave equation at the phase velocities coinciding with the bulk wave velocities is observed and analysed. Spectral analysis of Pochhammer – Chree equation is performed. The corrected analytical solutions for components of the displacement fields are constructed, accounting degeneracy of the secular equations and the corresponding solutions.

The dispersion waves propagating in anisotropic functionally graded (FG) plates with arbitrary transverse heterogeneity and arbitrary elastic monoclinic anisotropy are analysed within a recently developed six-dimensional formalism. The dispersion relation is obtained for all modes of dispersive harmonic waves propagating in an unbounded plate.

In work presented the results of research the algorithms of experimental data visualization, which obtain in the simulation of materials. The algorithms study was carried out on the example of the complete cycle for calculating the properties of an ideal diamond crystal. The calculation of crystal lattice properties was carried out using a software package for materials simulation. The obtained experimental data were analyzed using program REM_Viewer in which have been realized the algorithms of data visualization.

Geometrical parameters (coordinates and angles) of CeO2 crystal lattice by molecular dynamics method are calculated. Calculated parameters of crystal lattice are applied for definition the energy band structure via Hartree-Fock method in an approximation to CO LCAO (crystal orbitals as linear combination of atomic orbitals) and using the model of cyclic cluster. Calculated minimum energy band p-d is within the value range of experimental data. Valence band maximum is 4.2 while minimum energy band p-d width is 2.8 eV Quantum-chemical calculations are accelerated by Schwarz inequality and direct inversion method in iterative subspace. The obtained mathematical model is implemented into software package for calculating material properties.

The contribution is dealing with the wind tunnel measurements of dynamic pressures on the canopy roofs. It compares experimentally determined pressure coefficients Cp with the values in ČSN EN 1991-1-4 and former code ČSN 73 0035 as well. The pressures are expressed by the dynamic values. Thus, the averaged values are presented together with the fluctuating part, which significantly contributes to the overall loading. The measurement is carried out at two roof models, two basic directions, and two turbulence intensities.