The article is devoted to conceptual views on digital diplomacy as a tool of mass communication in public administration. The idea that in the era of information society building the mass media and the Internet industry development increasingly affects the sphere of international relations is substantiated. Of particular importance are digital technologies as a communication channel and a tool for influencing public consciousness. They become the most important tool for promoting the foreign policy interests of states - public diplomacy.The analysis of publications on the issue led the authors to the conclusion that the digital technologies of the MC take public diplomacy to a new level - digital diplomacy as an innovative way of conducting diplomatic activities. The authors emphasize that the very phenomenon of "diplomacy" requires scientists to rethink in the modern international information field. In this case, the so-called "digital diplomacy", which does not have any generally accepted, fixed conceptual basis, can be interpreted as a form of public diplomacy in public administration.Exploring digital diplomacy in public administration, the authors turned to the formation and implementation of US public diplomacy. It was found that among the tools of US public diplomacy, the most effective is higher education in the United States, as the world leader in the number of foreign students. In this regard, special attention in the United States is paid to foreign audiences, education of foreign students (cultural diplomacy), educational grants, international exchange programs, information countering of international terrorism, foreign policy opponents of the United States. It is noted that in US public diplomacy, when receiving American higher education, the US Department of State pays special attention to international exchange programs - projects for future leaders.The authors note that despite the development of public diplomacy in modern society, classical diplomacy continues to retain its basic functions and institutions. However, given the influence of modern social, political, economic and technological processes, the forms and methods of classical diplomacy are being transformed.The authors conclude that the rapid development of MC at the beginning of the XXI century. became the reason for the growth of information interaction and the transformation of information into an important political and economic resource. All this suggests qualitative changes that may occur in the content and purpose of the phenomenon of "diplomacy".The article substantiates the idea that under the globalization influence and the means of the MC a special form of diplomacy was born - the so-called "digital diplomacy". Compared to classical diplomacy, digital diplomacy has broader goals - to strengthen friendly ties and establish cooperation between people in different countries.As the main points, considering the public diplomacy formation in the United States, it was found that digital diplomacy in the United States was developed under the administration of George W. Bush in 2002-2003. Since then, digital diplomacy can be called a "digital" version of public diplomacy (Web 2.0 Diplomacy). So, there is a way to influence the foreign audience and the international situation with the help of the latest tools of the MC and modern information technology. In particular, US digital diplomacy is beginning to use social networks in US government diplomatic practice. Digital support for the interaction of American diplomats with foreign Internet users begins.Examining the formation of US public diplomacy, the authors note that digital diplomacy as a tool of the MC is becoming one of the areas in public administration. To intensify its policy, the US Department of State began to use the potential impact of the digital Internet on personal computer users and mobile phone owners.The authors suggest that the basis of US digital diplomacy is the ideological basis - the value of democracy and liberal freedoms. They are effectively implemented by the information policy of Google, Facebook, Twitter and other companies in the American Internet industry. At the same time, digital diplomacy can effectively create a positive image of the country, establish positive allied relations online, informationally and psychologically influence foreign audiences to achieve the desired result, and others.The analysis of the features of digital diplomacy as a tool of mass communication in public administration in the context of social development, allowed to characterize it as a structural component of modern public diplomacy. But the problems of using so-called "digital diplomacy" in the context of globalization remain largely part of the current political discourse and require further research.

Наведено характеристику іноземних гібридів соняшника, найбільш поширених у Степовій зоні України. Проведено пошук найбільш продуктивних гібридів соняшника для вирощування в умовах Луганської області, які мають велику пристосованість до умов недостатнього зволоження та великого забруднення полів вовчком соняшниковим. Викладено оптимальну технологію вирощування іноземних гібридів соняшника для отримання високого врожаю. Надано реко-мендації щодо обробки ґрунту, застосування мінеральних добрив, термінів сівби, норми висіву, догляду за посівами. Також описано основні заходи з догляду за посівами та боротьби з бур’янами. Наведені гібриди стійкі до зниження урожайності від нових рас вовчка й толерантні до фомопсису, білої гнилі кошику, білої гнилі стебла, стійкі до несправжньої борошнистої роси. Надано перспективний перелік іноземних гібридів, здатних за однакових умов вирощування давати високий урожай соняшника. The characteristics of foreign sunflower hybrids, which are most common in the Steppe zone of Ukraine, are given. A search for the most productive sunflower hybrids for growing in Luhansk region, which are highly adaptable to the conditions of insufficient moistening and large contamination of the fields by a sunflower broomrape, has been conducted. A broomrape is a parasitic plant, up to 65 cm high, which forms 500 thousand seeds having the ability to persist in the soil up to 20 years. The broomrape parasitizes on the roots of a sunflower and rapidly inhibits the growth and development, as a result of which the yield of the sunflower falls significantly. Among domestic hybrids, the majority is resistant to 4–5 races A-E, while foreign sunflower hybrids have a resistance to 7 races of A-G. The best technology of growing of foreign sunflower hybrids to obtain a high yield is described. In conditions of Luhansk region the best sunflower precursors are winter crops, corn, legumes, barley. In our case, winter wheat was a precursor of the sunflower. Recommendations for the soil treatment, application of mineral fertilizers, sowing time, seeding rates, crop care were provided. Since autumn, plowing to a depth of 25–27 cm was carried out. In the spring, in order to close the humidity by plowing, an alignment of the plowland was carried out. Due to the weak clogging with weeds, one pre-sowing cultivation was carried out to a depth of 5–6 cm. Strawberry herbicide Kratos was introduced directly before cultivation against the germs of weed vegetation. The main measures for the crop care and weed control are also described. Pre-emergence harrowing across the crops was conducted. In sunflower crops, 1–2 inter-row treatments with a ridger can be carried out to put the weeds in rows. One treatment was performed. Hybrids, which help to reduce the yield from new races and are resistant to: phomopsis, white rot of composite flowers, white rot of stems and unreal downy mildew, are shown. A perspective list of foreign hybrids that can produce a high sunflower yield under the same conditions of cultivation is provided. The best indicators for yield of tested hybrids by species with a humidity index of less than 8.0 % are Pioneer: P64LC108 with a yield of 27.75 c/ha, P63LE113 – 27.25 c/ha and PR64F66 – 25.00 c/ha. The best yields from the hybrids of the firm Limagrain were: LH5662 – 24.00 c/ha and LH50635 – 23.00 c/ha. Among the hybrids of Syngenta seeds the best result was shown by SI Arizona yield of 23.50 c/ha with 7.6 % moisture content.

We set the urgency of controlling Orobanche cumana Wallr. - a parasitic weed. The weed distribution is described, the regions of Ukraine with great number of Orobanche cumana are indicated. We also described the harmfulness of Orobanche cumana, loss of parts or all of the yield of sunflower, as well as the possibility of complete death of plants. We specified the morphological structure, biological characteristics, methods of distribution of seeds of Orobanche cumana, and germination and maturation. We underlined that parasite weeds penetrate into the root of the host plant and absorb water and nutrients from it with the help of gaustories. We suggested that these factors contribute to the infection of the sunflower by Orobanche cumana, the spread of the parasite and its racial composition. We preented the survey results regards the most productive measures of Orobanche cumana control. We described the classical methods of struggle against Orobanche cumana, which include: crop rotation, soil cultivation, and biological methods. We suggested that the modern, effective measures of struggle are the use of hybrids that genetically resistant to Orobanche cumana, the use of the production system "CLEARFIELD", and cultivation of sunflower using the technology "SUNEO".

Значне місце у вирішенні проблеми підвищення врожайності соняшнику займає удосконалення сортової агротехніки вирощування. Проведено досліди зі зміни ширини міжрядь у посівах гібридів соняшнику з 70 см до 15 см. У кожному з варіантів посіву були представлені по чотири варіанти густоти стояння рослин 70; 60; 50; 40 тис. / га. Дослідження проводилися на дослідних ділянках кафедри біології та агрономії Луганського національного університету імені Тараса Шевченка. У дослідах висаджували гібриди вітчизняної селекції Ясон, Гектор, Базальт, Сучасник. Ці гібриди охоплюють основні морфотипи і групи стиглості, найбільш поширені в колективних і фермерських господарствах. Отримані результати показали, що способи сівби мало впливали на якість насіння, але в більшості років спостерігається підвищення олійності на суцільному посіві. Згущення соняшника сприяє збільшенню олійності і зменшенню білковости насіння. Кращий за якістю насіння був гібрид Базальт. A significant place in solving the problem of increasing the yield of sunflower is taken by the improvement of the varietal agrotechnology of sunflower cultivation. The best technology of growing sunflower hybrids to obtain a high yield is described. In conditions of Luhansk region the best sunflower precursors are winter crops, corn, legumes, barley. In our case, winter wheat was a precursor of the sunflower. Recommendations for the soil treatment, application of mineral fertilizers, sowing time, seeding rates, and crop care were provided. In autumn, plowing to a depth of 25-27 cm was carried out. In the spring, in order to close the humidity by plowing, an alignment of the plow land was carried out. Due to the weak clogging with weeds, one pre-sowing cultivation was carried out to a depth of 5-6 cm. Herbicide was introduced directly before cultivation against the weeds. Hybrids resistant to: phomopsis, white rot of composite flowers, white rot of stems and downy mildew are recommended. Experiments were carried out on changing the width of the rows between the sunflower hybrids from 70 cm to 15 cm. Every varieties of plant standing were presented to each variant of sowing; 70; 60; 50; 40 th/h. The studies were conducted on experimental plots of the Department of Biology and Agronomy of Taras Shevchenko. Luhansk National University. In experiments, hybrids of domestic breeding Jason, Hector, Basalt, Suchasnyk were planted; these hybrids cover the main morphotypes and groups of ripeness, which are most common in collective farms. The results showed that the methods of sowing influenced the quality of the seeds, but in most years there has been an increase in oil content on continuous sowing. The thickening of sunflower promotes an increase in oil content and a decrease in the protein content of seeds. The best seed quality was the Basalt hybrid.

Проміжні культури є передусім важливим додатковим джерелом продукції сільського господарства. Вони дають змогу в сівозмінах інтенсивного землеробства значно підвищити коефіцієнт використання ріллі (КВР), який характеризує відношення площі посівів сільськогосподарських культур до загальної площі ріллі. З розширенням проміжних культур КВР зростає від 1 до 1,3. Залежно від термінів посіву основних культур, після прибирання яких обробляються проміжні культури, вони діляться на озимину, пожнивну, підсівну і післяукісні. Післяукісні проміжні культури висіваються після скошування основної озимини і ярових культур на зелений корм. Вибір післяукісних культур визначається конкретними ґрунтово-кліматичними умовами і господарськими потребами. У ґрунтово-кліматичних умовах півночі Луганської області з тирвалим теплим періодом зростання за достатньої вологозабеспеченності рослин в якості післяукісних культур використовуються кукурудза, гречка, просо, соя, соняшник та інші. У нашій роботі виявлено відмінності під час особливостей вирощування соняшнику в післяукісному посіві після озимого жита, прибраного на зелену масу. Досліди проводилися на дослідних ділянках Луганського національного університету ім. Тараса Шевченка в 2015–2017 роках. Після збирання озимого жита сіяли ранньостиглий гібрид соняшнику Pioneer P63LE113 по оранці і по-верхневій обробці ґрунту на гербіцидному («Трефлан» 4–5 л/га, «Харнес» 2 кг/га) і безгербіцидному фонах. На обох способах посіву установлювали страхові надбавки 20, 40 і 60 % до оптимальної переджнивної густоті стояння соняшнику на рядовому посіві 70 тис./га, широкорядному – 50 тис./га. Боронували соняшник бороною БЗСС-1,0, а на широкорядному посіві додатково за необхідності проводили міжрядні обробки. Найбільш високі урожаї забезпечуються під час посіву суцільним способом і підтримці полів у чистому від бур'янів стані. При цьому виключаються міжрядні обробки. Intermediate crops are primarily an important additional source of agricultural production. They allow crop rotation of intensive agriculture to significantly increase utilization rate of arable land (UR of AL), which characterizes the ratio of the area of crops to the total area of arable land. With the expansion of intermediate crops, the UR of AL increases from 1 to 1.3. Depending on the dates of sowing of the main crops, after harvesting of which intermediate crops are cultivated, they are divided into wintering, sowing and post-skeletal. Post-skeletal intermediate crops are sown after cutting the main winter crops and spring crops on green feed. The choice of post-ear crops is determined by specific soil-climatic conditions and household needs. In soil-climatic conditions in the north of Luhansk region with a thriving warm period of growth with sufficient moisture supply of plants, post-crop crops use corn, buckwheat, millet, soya, sunflower, and others. Our work revealed differences in the peculiarities of growing sunflower in post-crop sowing after winter rye, harvested on green mass. Experiments were conducted on experimental sites of Luhansk National University of Taras Shevchenko in 2015–2017. After harvesting of winter rye, an early-seeded hybrid of Pioneer P63LE113 sunflower was sown by rooting and surface treatment of the soil on herbicide (Treflan 4-5 l/ha, Harnes 2 kg/ha) and non-herbicide backgrounds. On both methods of sowing, insurance premiums were set at 20, 40 and 60 % to the optimal density of sunflower stand on ordinary crops of 70 th/ha, and broad-row – 50 th/ha. Flours of sunflower with harrow BZSS – 1.0, but on wide-range crop additional, if necessary, inter-row processing. The highest yields are provided when sown in a continuous manner and the maintenance of fields in a pure state of weeds. It eliminates inter-row processing.

Investigations were carried out into the special features of the formation of structural and chemical heterogeneity of the metal in the heat-affected zone (HAZ) of binary alloys, corresponding to different types of the equilibrium diagram. The results of the investigation of the high-temperature zone in the HAZ are presented, and the factors influencing the formation of the heterogeneity in the fusion zone of the grain boundaries of the metal are determined.

By means of 3D numerical simulations, we study the statistical properties of the fragments cloud formed during high-velocity impact of a spherical projectile on a mesh bumper. We present a quantitative description of the projectile fragmentation, and study the nature of the transition from the damage to the fragmentation of the projectile when the impact velocity varies. A distinctive feature of the present work is that the calculations are carried out by smoothed particle hydrodynamics (SPH) method applied to the equations of mechanics of deformable solids (MDS). We describe the materials behavior by the Mie–Grüneisen equation of state and the Johnson–Cook model for the yield strength. The maximum principal stress spall model is used as the fracture model. It is shown that the simulation results of fragmentation based on the MDS equations by the SPH method are qualitatively consistent with the results obtained earlier on the basis of the molecular dynamics and discrete element models. It is found that the power-law distribution exponent does not depend on energy imparted to the projectile during the high-velocity impact. At the same time, our calculations show that the critical impact velocity, the power-law exponent and other critical exponents depend on the fracture criterion.

Special features of the manufacture of brazed waveguide slot-array antennas are discussed. The method for calculating the approximate brazing conditions is described. Samples of equipment and devices for assembling and brazing of antenna arrays are outlined.

An approach for evaluating the current technical state of thermal equipment in thermal power plants is discussed. A system of parameters and corresponding criteria are developed for the technical state of groups of essential components of boilers and piping. Ascale for evaluation of safety factors is proposed in terms of the relationship between state parameters and the corresponding criteria. Analytic expressions are given for an approximate evaluation of the maximum lifetime limit for operation of an object in terms of an integral safety factor and an evaluation of this type is illustrated for the case of the live steam pipeline in a 300-MW unit. An algorithm is set up for actions to be taken by equipment owners in organizing monitoring of the technical state of the equipment.

To locate actively geodesic satellites stationed on the low Earth orbits lasers are often used via illumination of the satellites and detection of the laser reflected radiation. But, the lasers can strongly affect electronic devices of the satellites because of scattering of the laser radiation inside its optical systems. To exclude the influence of laser radiation on operating capabilities of the satellites, the characteristic properties of scattered laser radiation in a plane of receiver optical systems are studied in the paper.It is known that scattered laser radiation fields have a speckled character and registered speckles depend on both the laser and photo detector array spectral and power characteristics. In the paper, the laser radiation recorded experimentally in a focal plane of optical system by using photo detector array is investigated at various conditions of the array illumination. Theoretical analysis of the speckles is carried out to determine such characteristics of speckled images as dispersion and covariance and its dependence on the illumination conditions.

When selecting the method of low-temperature brazing, it is necessary to carry out design and technological analysis of the structure of brazed components which includes the analysis of the elements in the composition of sections (the presence of heatsensitive elements, barrier and technological coatings), types of joints, the density of the assembly of elements, etc. In most cases, the brazing of electronic components is carried out using brazing with a wave of the brazing alloy and also furnace brazing in convection and infrared furnaces. However, in a number of cases, the structure of the component does not permit general heating and contact introduction of energy. These structures are usually brazed by laser or light beams. To produce high-quality joints in these components, it is important to select correctly the parameters of the conditions, such as the duration of the heating process and the temperature of heating. Selection requires timeconsuming experiments with brazing of full-size specimens or calculation of the parameters using the mathematical models of the heating process. The application of the models for ensuring the appropriate adequacy is a more rational method of solving the problem and is characterized by a minimum expenditure. The Department of Technology of Welding Processes of the Institute has been investigating the technology of low-temperature light beam brazing (LBM) of the CFE. The composition of these components includes heatsensitive electronic–optical elements (superluminescent and laser diodes), which lose the emitting properties on heating to temperatures higher than 1258C. Consequently, localized supply of energy is essential for assembling of these elements. The presence of electronic–optical elements is the reason why it is not permitted to use fluxes and, consequently, gold coatings must be deposited on the elements to be brazed in order to ensure satisfactory wetting. In this study, it is proposed to carry out lowtemperature LBM using an indium-based alloy as the brazing alloy which is characterized by a low susceptibility to the dissolution of the gold coating and ensures satisfactory characteristics of wetting and spreading of the brazing alloys without using the flux. The heat source was a small light beam apparatus, Luch-3M. The main component of the equipment for light beam heating is the radiant heating module (RHM) which consists of an emitter, a focusing optical system (FOS), current supply elements and adjustment devices. The module also includes the FOS based on an ellipsoidal reflector and a lamp of the DKsSh series with a power of 100–500 W. The main parameters of the process of LBM are the lamp current and the duration of the heating process. To determine these parameters, investigations were carried out to develop a mathematical model of the process of heating of brazed elements with the focused light beam and a flow of the brazing alloys through the gap under the effect of capillary forces and forces of gravity. The mathematical model is based on the program Ray-1 written in Visual Basic language and consists of two modules for calculating the output energy characteristics of the RHM, and also thermal fields, formed as a result of the interaction of the radiant flux with the surface of brazed components, and the duration of the process of heating the component in the nominal working conditions of the lamp. The program can be changed, depending on the design of the RHM and the brazed components of the module. The energy characteristics of the module were calculated using the procedure proposed in Kholodilov. According to this method, in the calculation of the density of the radiant flux in the heating spot, the glowing body of the lamp arc is divided into five fictitious radiation sources with the same brightness. The initial data for the calculation are the geometrical and optical characteristics of the reflector of the RHM and also the light engineering characteristics of the lamp. The density of the radiation flux is calculated using the following expression:

In the report building and application questions of picosecond terawatt CO2 laser installations are presented. The design and the description of the basic components of middle-infrared picosecond laser facility (MIRPLF) with terawatt power of 10 &mgr;m laser radiation manufacturing by efforts of institutes NIIKIOEP and NIIEFA are presented. The main attention is paid to questions of design of the master oscillator with pulse with 10÷100 ps and the final laser CO2 high pressure amplifier (HPA) with the intermediate water capacitor integrated in to the gas-discharge chamber. The main results of experimental investigations of characteristics of MIRPLF components are presented and prospects of MIRPLF projected peak power increasing are analyzed.

The terawatt picosecond CO2-laser design is considered in the paper. The CO2-laser system includes itself the following units: a) master oscillator with variable pulse width of 100 ps, and b) laser pre-amplifier being developed on a basis of a ring optical scheme and operating under the gas pressure of 3 atm. Both experimental and theoretical analysis of the CO2-laser system is carried out.