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Studies of extreme nonlinear optical effects, in which dissipative factors such as absorption and amplification of light in a medium play a fundamental role, are reviewed. The generation of pulses with extremely short duration down to unipolar ones is analysed by tracking the development of ideas related to the self-induced transparency phenomenon, whose practical application becomes real for extremely short pulses in lasers and laser media. Extreme radiation structuring is achieved in dissipative (laser) solitons characterised by a complex topology of phase and polarisation singularities, which is of interest for coding information.

The article presents the results of the study of new hybrid combinations of rediploid maize lines obtained by the diallelic scheme of crossing. The experiment involved simple hybrids of six homozygous lines. The degree of manifestation of heterosis according to the main morphometric parameters of the plant (stem length, ear height, panicle length, stem diameter), as well as the combinative ability of lines and components of genetic dispersion, was revealed. The ways of possible use of lines and hybrids in the breeding process are noted - for tall stature, resistance to lodging, manufacturability. The influence of overdominance in the manifestation of the length of the panicle and the diameter of the stem and the predominance of additive effects in the formation of the height of the ear were noted. Analysis of the components made it possible to identify the number of genes or groups of genes that influenced the manifestation of traits in 2021 (stem length - 1-2, cob height - 2-3, panicle length - 1-2, stem diameter - 2-3). A significant influence of cultivation conditions on the manifestation of the length of the stem, the height of the cob, the length of the panicle, and the diameter of the stem was noted.1.

Unipolar pulses have a nonzero electric pulse area (integral of the electric field strength with respect of time in a given point of space). Due to unidirectional action on charges they can be an efficient tool for ultrafast control of wave packet dynamics in matter, charges acceleration and so one. In this paper, we briefly revise recent advances (including the results obtained by the authors) in optics of extremely-short unipolar half-cycle pulses.

The propagation of a unipolar light pulse with a duration of less than one period in a two-level resonant amplifying medium is studied theoretically. In the process of amplification, the unipolar pulse becomes bipolar. The effect of the relaxation time on the shape and duration of the amplified pulse is demonstrated. It is found that the electric pulse area (integral of electric field strength with respect to time) is conserved, in contrast to the area under the long pulse envelope (integral of slowly varying field amplitude with respect to time), which, in the case of long pulses, satisfies the McCall – Hahn area theorem.

The article presents the results of comparative studies of the rheological properties of the ceramic polymer blend of polylactide (PLA) filled with 50 %vol alumina to evaluate the possibility of obtaining extruded filament for 3D printing.

The paper established that depending on the number of natural brown flax bran and squash the prefabricated poultry meat does not significantly change its indicators, but the most optimal is sample No. 2 – with the replacement of the wheat bread norm with 50% natural brown flax bran; with the replacement of the water norm with 50% squash – Kurazh. The content of amino acids in Kurazh balls was higher than in the control sample, which indicates their biological value and quality. The study of the content of such acute deficient amino acids as lysine, methionine and tryptophan showed that the Kurage balls exceed the control sample in amino acids: lysine – by 77.6%, methionine – by 125.5%, tryptophane – by 78.1, respectively. A new kind of balls with functional ingredients has a number of useful properties for the human body and may be recommended for gerodietetic nutrition.

The paper presents the results of a study to explore the influence of different behaviors of rams bred by crossing the Prekos and the Edilbay breeds on the technological properties and quality of meat and meat products. It was found that the meat from rams of the first, strong, type of behavior has the best technological properties and got a high tasting rating – excellent quality. Meat processing has kept the brand, the best quality product “Pressed Boiled Lamb” is also produced from the meat of rams coming under a strong type of behavior.

The paper analyzes the possibility of not only expanding the range of healthy food products, but also reducing its cost due to the combination of natural animal and plant raw materials. The possibility of introducing an innovative approach to the creation of products aimed at healthy nutrition was considered. It was found that the inclusion of plant additives into traditional meat-containing products will not only contribute to high quality products, but also products with increased nutritional and biological value. It was proved that the inclusion of plant ingredients ensures products with functional properties, high physicochemical and organoleptic indices. It was revealed that the proposed technological scheme and formula of a new type of meat-containing semi-product in dough with the introduction of vegetal raw materials will make the product more functional. The obtained results showed that the inclusion of wheat bran, nettle and onions in minced white meat will make it possible to enrich the product with essential nutrients. The obtained results of the study show that the combination of natural and plant raw materials makes it possible to obtain a product with high quality at a low cost aimed at improving the health of large population groups.

Young lamb has high nutritional properties due to its high protein, amino acids, vitamins and microelements content. However, the specific odor and the high fat pour point are the main obstacles to the industrial use of lamb. The purpose of our research was to study the physical and chemical characteristics of raw lamb after ultrasonic salting and to select the optimal processing conditions and their economic justification. Experimental samples were salted in the devices UOM - 2 and PSB - Gals at 35 kHz ultrasound frequency, as well as using an ultrasonic submersible emitter at 26 kHz. Ultrasonic treatment has led to an increase in the pH and moisture content of the raw material, as well as in product yield. With an increase in the salting time, the water activity (Aw) decreased. Based on the results of physicochemical samples studies and comparative analysis of the economic efficiency, a submersible ultrasonic emitter with an ultrasonic frequency of 26 kHz and a salting duration of 12 hours was recommended for lamb delicacies salting.

We demonstrate the possibility of inducing, erasing and extra rapidly controlling population difference gratings resulting from coherent interaction of unipolar subcycle pulses with a resonant medium. Gratings can be produced without overlap of pulses in the medium, which is an important distinction of the proposed approach from the traditional one, in which gratings are produced using interference of two or more overlapping quasi-monochromatic light beams. The use of unipolar subcycle pulses ensures faster control over gratings in comparison with bipolar pulses studied by us previously.

Electromagnetically induced gratings (EIG) are created by standing-wave laser field in resonant media. Such gratings can be also created by few-cycle electromagnetic pulses counter-propagating in the medium via coherent Rabi oscillations of atomic inversion. In this case, instantaneous cross-section of the pulses in the medium is not necessary for grating formation. In this paper, we revise our recent results in study of such grating formation and their control by few-cycle pulses coherently propagating in a resonant medium. We demonstrate the grating formation and their control in three-level medium excited by three subcycle THz pulses.

The main problem of the functioning of the organizational, technical and technological structures of the enterprise is the insufficient formalization of business processes, which, in turn, is based on the uncertainty of business process tasks influence level to the whole process, which complicates its further effective development. In this article, the structuring of such elements is based on the approach of forming the system of design and technological preparation of production (DTPP) at the enterprise, and the business processes are the subject of the study. The objective of the study is to improve the DTPP control system within the framework of research and development (R&D) with further deeper formalization for the implementation of an automated DTPP control system. To achieve this objective, tasks for assessing the business processes of DTPP control have been identified, as well as for analyzing the effectiveness of the business processes tasks for DTPP control. To achieve the target goals and solve the tasks, the research plan includes such stages as the formation of a schedule of research, identifying the necessary resources and their sources, identifying the direct executors and bringing the plans to them, fixing the results of planning in the form of a project. The study is based on the use of expert assessment method. To obtain the correct result from two groups of expert assessments, individual assessments have been used, which are based on the use of the individual experts’ opinions who are specialists of the enterprise, and functionally independent from each other. The implementation of the individual assessments formation is based on an individual expert survey in the form of an interview with an analysis of expert assessments.

To date, a large number of experimental methods for determining the mechanical properties of composite materials is known. However, the results of these methods. i.e. their comparison features, are relative and give good repeatability in strict compliance with the sample production and experiment technology. In this case, the stress-strain state in the working area of sample structures should be numerically evaluated to determine the generally accepted characteristics. This paper constructs and develops the simplest models of the mechanical behavior of polymer composite material samples. The stress-strain state is numerically simulated in the working areas of samples with various geometric parameters and external loading features. Modeling is made using the ANSYS engineering analysis system. According to the results of calculations for each of the samples, the fields of stresses, deformations, and displacements under compression and tension are obtained for medium models: effective isotropic medium, effective anisotropic medium, and layered composite with effective anisotropic medium texture layers.

The lack of integration solutions for transferring data according to the information model of the capital construction object or certain parts of the information model between different systems (for example, from the customer to the expertise, from the contractor to the State information system for the provision of urban planning activities (GISOGD) or other state information systems) leads to the loss of data and important information stored in the information model, which accounts for reproduce or transmit in native format without the possibility of data processing by the information system. The purpose of this article is to analyze the world and domestic experience of using XML schemes for organizing the processes of transferring and storing structured data in information systems (including government ones) and software with a reasonable selection of best practices.

A kinetic model that describes the evolution of residual stress in thin polycrystalline films during bombardment by ions with energies below the sputtering threshold is presented. The mechanisms responsible for the change in stress are the generation of point defects on the surface and their redistribution over the film thickness along grain boundaries. The presented model was used to explain the experimental data on the change in stress in thin Cr films after treatment in Ar plasma of low-pressure RF induction discharge with ion energy of 15-30 eV.

The paper deals with the experimental study of mechanical behavior and the common factors of deformation of structural composites in combined use of contactless optical video system and acoustic emission analysis and registration system. The experimental studies were conducted at the electromechanical testing system Instron 5989 in compliance with ASTM 5766 recommendations for the samples of spatially reinforced and fiber-laminated carbon fiber composites with open holes. The preform-based carbon plastic samples with spatially reinforced structure are obtained by 3D-weaving methods. The paper presents the results of mechanical strain tests of open-hole samples. The authors obtained stress and strain diagrams for carbon plastic of various structures and analyzed the evolution of non-homogeneous strain fields on the surface of 3D-reinforced composite samples of the studied structure. They observed the difference in mechanical behavior of spatially reinforced and fiber-laminated carbon fiber composites. The paper presents the images of the samples with the characteristic damages in the area of the opening. Using the acoustic emission signals recording data, the authors obtained the diagrams of dependence of cumulative power, which allowed to observe the diverse nature of damage accumulation for the studied groups of samples.

The article presents the results of numerical studies and analysis of the feedwater regenerative heating operating modes depending on power unit capacity. The main parameters of this system are the enthalpy of the turbine steam extraction for heaters, as well as the steam consumption in these extractions. The dependences of the turbine unit steam flow rate and the change in expansion process of the steam turbine during the load regulation were investigated. The mathematical model of calculation the thermal power plant for a 300 MW power unit capacity was developed. Following on the results of the calculation conclusions of feed water regenerative heating operating modes at reduced loads of a turbine-generator for a 300 MW unit.

Various approaches are used to improve baker’s yeast technological properties of and final products quality. Because of low-frequency ultrasound does not have a destructive effect on yeast cells, the aim of our research is to test a new method of improving the technological properties of baker’s yeast using low-frequency ultrasonic cavitation. The object of the study was active dried baker’s yeast Saf-levure (France). All experimental and control samples were processed in a “Grad” ultrasonic bath (Russia) with different intensities and processing times at a frequency of 35 kHz. It was shown that precure of baker’s yeast with ultrasound at a frequency of 35 kHz, an intensity of 0.5-1 W/cm2 and an exposure of 1 and 3 minutes redound to improving the baker’s yeast technological properties: the yeast specific growth rate increases by 1.8–2.7 times, and yeast rising power - by 1.2–1.6 times. At the same time, baked with ultrasonic-treated yeast bread has significantly improved physicochemical and organoleptic characteristics compared to traditional bread. Acidity and humidity of the bread crumb decreased by 1.2 and 1.3 times and porosity increased by 1.6-2.5 times with an increasing the time and intensity of the sonication. With increasing of sonication time and intensity, the bread crust became golden brown, the color of the crumb became lighter, and the loaf shape fluffier. The best results are obtained after precure of baker’s yeast suspension with ultrasound at a frequency of 35 kHz, an intensity of 1 W/cm2 and an exposure of 3 minutes.