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This study investigates the numerical simulation of fluid flow in a flat layer near a porous bottom layer in gravity field. The porosity distribution along the bottom is assumed to be homogeneous. The upper part of the layer is free of the porous medium, while the porosity is in the lower part. This task describes, for example, the flow near bottom vegetation. The problem is solved using the Lattice Boltzmann Method. The porous medium is simulated by the representative elementary volume (REV) method. The system is studied in an isothermal formulation with different porosity and permeability coefficients.

This study investigates the natural convective flow within an horizontal two-layer system driven by daily temperature fluctuations. The upper part of the layer is free of the porous medium, while the porosity is in the lower part. A homogeneous porosity distribution is assumed along the bottom, mimicking the flow near bottom vegetation or sludge. The Lattice Boltzmann Method is employed to solve the problem. The porous medium is simulated using the representative elementary volume (REV) method. An additional set of distribution functions is implemented to capture temperature distribution. Simulation is performed at constant porosity coefficient and at different Darcy number.

The construction industry is undergoing a change in approaches to the design of capital construction projects due to the preparation of consolidated digital models in the course of designing and working with the information placed therein. This requires updating the content and changing the format of training students in the fields of study and specialties related to the design of capital construction projects and their engineering systems. Based on the comparison of the current format of training engineering students to the format of professional activities of engineers involved in the design of capital construction projects, it is shown that today’s training system does not fully take into account the specifics of team work of engineers of various profiles in the course of project development. The necessity of using methods of cross-discipline team training is substantiated. It is proposed to use the best practices in competence R94 “Engineering Design” of the WorldSkills Russia “Young Professionals” national championship as a methodological basis for organizing such training format.

It is known that the efficient kinds of photocatalytic additives for cement materials are “core–shell” compositions synthesized by precipitation of photocatalyst particles on mineral substrates (dispersed carriers). The study aim was to install patterns of influence of 5 mineral modifiers on the technological characteristics of cement systems with finding of the most promising raw materials for dispersed carriers of photocatalytic agents. The increased technological efficiency of silica fume, metakaolin and expanding sulfoaluminate modifier in cement paste, due to the peculiarities of their granulometric composition with high dispersity and defectiveness of particles, was revealed by the research results. It predetermines the prospects of using these mineral additives in the composition of photocatalytically active self-cleaning cement materials.

The purpose of this publication is to describe a phenomenon that is fundamentally important and, at the same time, hardly elucidated in the literature. In the process of film condensation of vapor on the bundles of horizontal tubes, a developing region of the thermal boundary layer is formed on each tube of the bundle; the role of this region in heat transfer is important, and in some cases decisive. The paper presents experimental results on the influence of various contributions of the developing region on heat transfer during film vapor condensation on tube bundles. Based on the data obtained, an algorithm for calculating a condenser during condensation of a stationary vapor without non-condensable impurities is proposed.

The paper presents 3D numerical modeling of spreading dynamics of R21 (mol. fraction: 0.9) and R114 refrigerant mixture film. We considered an outer flow along a round vertical cylinder at Reynolds numbers of 50 and contact angles of 10°, 30°, 50°, 70° and 90°. The simulation was performed in OpenFOAM software on the basis of the volume of fluid (VOF) method. We obtained that the contact angle has a key effect on the wetted area due to the change of liquid spreading modes over the cylinder. At that, we distinguished the following flow modes: the stable jet mode, the cascade jet mode, the jet-droplet mode and the drying mode. These modes are similar ones for horizontal tubes. In some flow modes over the vertical cylinder, we demonstrated the existence of the back liquid flow between jets, directed against gravity.

The article presents the results of two-year studies on the biological effectiveness of biofungicide Serenade, ASO, SC (Bacillus amyloliquefaciens, strain QST-713, titer not less than 1x10 9 CFU/ml) in the fight against bacterial black spot on the leaves and fruits of indoor tomatoes in the conditions of the II soil-climatic zone of the Crimea. It was found that a five-time treatment with biofungicide Serenade, ASO, SC, the rate of application of 5.0, 6.5 and 8.0 l/ha, contributed to a decrease in the intensity of development of Xanthomonas campestris pv. vesicatoria on leaves by 2.3-2.9 times, on fruits by 2.2-2.7 times. On the 10th day after the fifth spraying, the biological effectiveness of biofungicide Serenade, ASO, SC in the application rates of 5.0, 6.5 and 8.0 l/ha, with an average development of bacterial black spot on the control variant (3.3-5.2% on leaves, 2.9-3.3% on fruits), on leaves was 76.5-85.1%, on fruits – 71.6-75.0%. On the day of the last harvest, on the 29th day after the last treatment, the biological efficiency on leaves was 57.3-65.4%, on fruits – 54.5-62.6%. The difference of five-time treatment with biofungicide Serenade, ASO, SC in the norm of application of 8.0 l/ha, with the standard is insignificant, within the limits of experimental error. The positive effect of biofungicide Serenade, ASO, SC on yield was noted. The difference with the control (77.9 c/ha) is 34.9, 36.9 and 41.0 c/ha.

At the present stage of science development it is necessary to develop and implement the grape breeding programs for immunity basing on the international level of knowledge about the genetics of immunity to pathogens that cause culture diseases. The extensive material on genes of grape resistance to Plasmopara viticola and Erysiphe necator (Uncinula necator), which cause mildew and oidium diseases, has been collected thanks to the MAS technology. There is an evidence of necessity to pyramidize genes of resistance to these pathogens in one progeny genome for consistent field resistance to the complex of these pathogens. However, even at present, the issue of study the transfer of specific genes of resistance from parents to the progeny, their combining ability in one genome, and gene expression during pathogenesis remains relevant. This publication discusses the formation of grape breeding program in the FSBSI Institute Magarach of the RAS on introgression of resistance genes of the species Vitis rotundifolia (Muscadinia rotundifolia), and also presents the results of phytopathological screening of populations resulting from crossing with this species.

Rotary bucket dredgers are used in various operations: dredging, mining, development of all types of soil. Despite their high weight, cost and complexity of construction, they are increasingly used in underwater soil development due to their versatility and high efficiency. The article presents the developed method for calculating the rotary bucket dredgers, taking into account their placement under water.

Approximately 95% of the total heat losses of a greenhouse for year-round use are losses through translucent enclosing structures. Therefore, to reduce energy costs, the area of the enclosing structures of the cultivation structure should be minimal. The purpose of the study included the derivation of formulas to substantiate the energy-saving space-planning parameters of greenhouses offered by the market for farms, and a comparative assessment of various types of structures. Formulas were obtained for determining the minimum fencing factor for greenhouses of various shapes, on the basis of which they were compared in terms of heat losses and material consumption for enclosing structures.

Key performance indicators, KPI are a proven cutting-edge tool for process productivity and staff performance monitoring. Therefore, today it is possible to find the use of this tool in the most varied spheres and industries. However, the system implementation is a long and painstaking process, which requires financial, labor and time expenditures. But in case of its successful implementation, KPI technology will provide the balance of advantage for the company management and contribute to its growth. The article presents the selection mechanism of KPI system development and implementation methods. Using key performance indicators, the organization is able to manage the process and modify it, as well as define objectives for employees and motivate them to achieve their objectives. KPIs are based on measuring quantitative benefits. Control shall be based on comprehensive and reliable information about the company’s process productivity. This is the only way to take quick management decisions, make adjustments to the operation of processes that will contribute to the achievement of strategic objectives as a whole.

The research deals with the analytics of the features of business processes of a digital agency and the identification of promising aspects of digital marketing as a tool for B2B interaction in the Foodtech market. It is noted that the primary trend of the Foodtech sector deals with digital transformation. From the strategic point of view of creating a business model, it is necessary to understand that digital transformation involves the installation of modern hardware or software and fundamental changes in approaches to management, corporate culture, and communications. To increase the efficiency of the digital agency’s business model, the authors propose to consider digital marketing. The analysis of the effectiveness of the business model of the digital agency allowed us to identify the most problematic and, at the same time, promising components of the business model. Based on generalized approaches to business model management in the case of a digital agency in the design of relevant services, it is proposed to consider maximizing the speed and efficiency of business model transformation and minimizing the uncertainty of further digital service development based on customer relationship management.

Sweet sorghum hybrids F1 in productivity can surpass the parental forms on 50-60%. Thus the breeding process is aimed to develop first generation hybrids with a strong potential of productivity and quality of green mass and silage. The purpose of the work is to study heritability and heterosis of the quantitative traits of sweet sorghum hybrids F1 obtained on a sterile basis. The study was conducted in 2013-2015 on the lines with cytoplasmic male sterility (‘A-63’, ‘Knyazhna’, ‘APV-1115), the varieties (‘Listvenit’, ‘Severnoe 44’, ‘Zernogradskoe 454’, ‘Stavropolskoe 36’, ‘Galiya’ and ‘Larets’) and the hybrids. The inheritance of green mass productivity and absolutely dry matter, the length of a vegetation period, plant height and leaf formation (foliage), protein content in dry matter of the hybrids occurred according to the type of dominance and overdominance. It has been determined that while choosing the parental forms for hybridization it’s essential to select the forms with differences in the vegetation period of 4-6 days to avoid the dominance of late maturity. The height pollinator increase results in the hybrid height increase and large heterosis. It’s necessary to select the parental forms with maximum foliage to improve leaf formation in the hybrids.

Viral infections cause the reduction of yields and efficiency of vine cultivation in all viticultural regions of the world. Simultaneous infecting with several viruses, the so-called mixed infection, can significantly increase the severity of symptoms. The article presents the results of study of mixed infecting of grapevine with viruses in the vineyards of the Crimean Peninsula during 2011-2020. More than 800 grapevine samples of 153 varieties selected in 23 vineyards of the Crimea were analyzed over the entire period of study. Presence of phytopathogenic viruses in the samples was determined by RT-PCR using virus specific primers. The share of 25.5 % of all the samples tested gave positive result for one or more of the following viruses: GFLV, GLRaV-1, GLRV-2, GLRaV-3, GFkV, GVA, GRSPaV, ArMV, GFLV. During the process of studyno vines affected by GVB virus were identified. Single-agent infection was found in 20% of the examined vines. The amount of vines affected by mixed infection was 5.48 % of all tested. In a mixed viral infection more common combinations are: GRSPaV/GFkV; GVA/GRSPaV; GVA/GLRaV-1/GRSPaV; GVA/GLRaV-3/GRSPaV. Vines were infected the most with GRSPaV and GFkV viruses, which is visually manifested in the form of mosaic leaf variegation, leaf chlorosis and the appearance of necrotic spots.

Heat treatment was used as a method of improving the health of grape plants from the phytoplasma. The Binder KBWF 240 growth cabinet was used for thermotherapy, in which plants of the Tsitronny Magaracha variety were cultivated in vitro under simulated conditions with a treatment period of 14 days. The results of repeated testing of samples showed the efficacy of treatment of this grape disease: out of 13 samples of the Tsitronny Magaracha variety, only one revealed the latent form of phytoplasma blackening of grapevine wood Bois noir. To improve the health of grape plants obtained in vitro culture, it is advisable to use the developed technological operations with thermotherapy in the growth cabinet, which allows to rid the planting material of the latent form of phytoplasma associated with blackening of grapevine wood Bois noir.

The article investigates the relationship of flows of various types (transport, cargo, information, financial, energy, legal and others) between themselves and elements in the delivery system of foreign trade cargo. A hierarchical scheme of points of interaction of various types of flows is proposed. It is note that optimization of flow control will create more favorable conditions for rhythmic work and coordination of transportation with other modes of transport, and a correctly calculate supply of goods to ports and border crossings will provide an opportunity for the economical use of rolling stock. The solution to this problem at a new level has become possible due to the widespread introduction of digital information technologies. A model of the topology of their interaction has been develop with the definition of an integral quality indicator of a particular route or delivery option. An algorithm for assessing the interdependence of various types of elements, flows, legal ties and the degree of complexity of the structure of the system for the delivery of foreign trade goods.

Traffic flows associated with the movement of passengers and goods, characterized by traffic intensity, speed, direction and other factors are closely interrelated. The planned traffic intensity of these flows is de-termined by calculating the carrying capacity of the elements of the transport system or links in the delivery chains. The article provides a comprehensive analysis of the throughput capacity of a railway line, rail-way station, railway stations and landside areas, airports, and highways. Calculated dependencies, used to determine the carrying capacity of transport infrastructure facilities, have been carry out. It is shown that the throughput (capacity) of infrastructure facilities is focused, most of all, on the volume of cargo transportation in various industries. The factors that must be take into account when determining the conditions for further de-velopment and increasing the capacity of transport infrastructure elements are noted. All calculation methods are reduced to determining the maxi-mum permissible volume of cargo transportation (in passenger traffic, - passengers) that can be passed (processed) by an infrastructure object per unit (for a certain period) of time in the considered road transport and weather and climatic conditions.

The article is devoted to actual problem of development and introduction of the replay system of the current location and direction of movement, in real time vessels and aircrafts, intended for continuous monitoring and obtaining data on the characteristics of vessels.

In this paper we picture and compare national systems of innovation of four Asian countries (China, Korea, Japan, Taiwan) with some characteristics of their prolific inventors. The evolutionary model of the growth of knowledge through recombination enables us to explain the inventor productivity, mobility as well as their mobility and the value of their invention. Thanks to patents date from the NBER data set we can estimate a set of relations. Our findings are: 1) the determination of the invention value by the inventor productivity is verified for the four countries, 2) inter firms mobility has a positive impact on productivity in China et Taiwan but no impact in Korea and Japan, 3) inventor international mobility play a role on invention value in Taiwan. Inventor technological specialization has a positive effect on his productivity and a negative effect on his mobility.