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The aim of this work was to compare the quality of milk and its suitability for processing into cheese in cows of the local Ukrainian black-and-white dairy (UBW) breed and their crossbreeds with the Swiss breed. The research was conducted on a commercial farm in Vinnytsia region. The first farm keeps purebred cows of the Ukrainian black-and-white dairy breed and crossbreeds of the first generation obtained as a result of crossing with the Brown Swiss breed. Two groups (purebred and local) analog cows were formed with 20 heads each. It was found that crossbreeding had a positive effect on the content of fat and protein in milk in crossbreeds UBW and Brown Swiss cows, these values were 0.21 and 0.13% higher than in purebred cows. At the same time, the crossbreeds lost some of their productivity - the average daily yield of UBW and Brown Swiss cows was 1.83 kg lower than that of purebred counterparts. The crossbreeds of UBW and Brown Swiss cows were dominated by purebred analogues in terms of energy value of 1 kg of milk and theoretically possible yield of rennet cheese by 0.141 MJ and 0.53 kg. The duration of the coagulation phase of milk obtained from crossbred cows was shorter than that of purebred analogues: in crossbreeds of UBW and Brown Swiss cows by 1.23 minutes. Samples of milk obtained from crossbreeds had the highest class on the characteristics of the rennet clot. Out of 20 studied samples of milk of UBW cows of breed 15 samples (75%) are referred to I and 5 (25%) - to II class; in the milk of UBW and Brown Swiss breeds of cows 17 (85%) - up to I and 3 (15%) - up to II class.

This study is aimed at improving the efficiency of photovoltaic plants operated in the electric networks of various densities by adjusting the synthetic inertia algorithm and automatic frequency control circuits. To this end, the automatic control system of a photovoltaic plant was investigated using hybrid modelling methods in an all-mode online simulation complex of electric power systems. It was shown that the stability of photovoltaic power plants could be improved through the use of synthetic inertia. According to the conducted research, effective operation of this algorithm can be ensured by a correct determination of the bandwidth of automatic frequency control. Operation of this automatic frequency control circuit can lead to the oscillations of various frequencies during the installation of photovoltaic power plants in low-current electrical networks (electrical networks with the short circuit coefficient of less than 10 a.u.) and, subsequently, negatively affect the operability of the synthetic inertia algorithm. In addition, in high-current networks with an increased bandwidth of the automatic frequency control unit, the value of the network frequency reduction decreases (optimal bandwidth of 50 Hz). Conversely, in low-current networks, the automatic frequency control unit, under an increase in the bandwidth, decreases the response rate of the synthetic inertia algorithm, which leads to an increase in the frequency reduction value (optimal bandwidth of 0.3 Hz). Thus, the conducted investigations showed that the automatic frequency control circuit in the control system of a photovoltaic power plant can be used to alter the operation of the synthetic inertia algorithm. However, the nature of this effect depends on the electrical network density and can be both positive and negative. The effect observed in the tested power system was confirmed for a real-dimension power system.

The aim of this work was to study the effect of low temperatures on productivity, microclimate parameters and comfort of keeping cows in different variants of prefabricated premises. The research was conducted in the central part of Ukraine (Kyiv region, Bila Tserkva district) in three farms where animals are kept loose at different sizes of prefabricated premises. The first option is a prefabricated room without insulation elements; the second prefabricated room with elements of warming of side walls by polycarbonate glass; the third in an easy-to-assemble room on a deep, long-lasting straw litter. The average annual number of dairy cows in all farms is 400. The studies were performed in the thermoneutral period, when the average daily ambient temperature did not fall below -5.0 ° C (17 days) and the period of high-temperature load, when the value of the average daily ambient temperature was -15 °C and below (11 days). It was found that prolonged low-temperature load significantly affects the comfort of cows in the options for keeping in easily assembled rooms of different types. The average daily air temperature in all variants of easily assembled rooms was negative. At the same time, during boxing without insulation elements, the temperature was -5.3 ° С, which is slightly lower than the permissible values ​​recommended for dairy cattle. The best values ​​among prefabricated premises in terms of microclimate indicators, bioclimatic indices, resting place temperatures and energy costs for heat production were for the use of polycarbonate glass insulation systems during the winter period. The use of elements of insulation of easily assembled premises provided the lowest among the studied options of premises reduction of productivity in the period of low-temperature load.

Modern cattle selection programs are characterized by the increase of traits with a low level of genetic determination. This change is associated to a technical means of verification capabilities (automated milking systems, behavioral video surveillance systems, control of rumination process, etc.), the success of genomics when selection based on genetic markers requires additional controls over the phenotypic changes. But the basic selection remains the production economy-based selection process. Recently, more features related to reproduction and productive longevity or animal health have been included in this group. A study was carried out on the effects of genetic and environmental factors on the voluntary waiting period, the open days and milk productivity. A new feature was identified – the insemination period which was defined as the difference between the length of the open days and the waiting period. Investigations were carried out on Holstein cows (605 heads in total), the average milk yield which amounted 8777 kg. The majority of the primary information was the data of the Uniform Agri program, which analyzed using variance and correlation-regression analysis. Weak probable impact of the «father» factor on the 305-day milk yield of lactation (11.5 %), the open days (5.4 %) and the insemination period (5.2 %) was identified. A positive, reliable and weak correlation was found between lactation milk yields and service period (0.115, p ≤ 0.01.), and between service period and voluntary waiting period (0.257, p ≤ 0.01). The dependence of the length of the service period and the voluntary waiting period on paratypic factors such as the age of cow’s lactation and the month of their calving is investigated. As such, a tendency to reduce the length of the open days and the voluntary waiting period in cows with each subsequent lactation. It is found that the length of the voluntary waiting period was the largest in cows that calved in November, March, May, and the shortest – in August. At the same time, cows that had calved in March was the largest the open days, and with calving in February – the shortest. It was concluded that the possibility of using the value of the insemination period in the selection programs. The possibility of using the traits of the level of reproduction in the selection programs has been proven.

The article attempts to investigate the historical circumstances of technological renewal of the fleet of freight cars of the state railways of Ukraine in 1918-1919. It is found that in conditions of political instability and deep economic crisis its sustainable operation. The need for coherence in the operation of railway transport was due to the aggravation of the final act of the First World War, which also affected the technical task of rolling stock in the context of its equipment with means of transporting troops. It is determined that against the background of limited available resources, domestic machine-building enterprises presented conceptual samples of biaxial covered freight cars of the NTV type, developed on the basis of all the requirements of the time, taking into account possible technical replacements of individual components. The reasons for the slowdown in the process of renewal of the rolling stock of state railways, as well as the general restoration of the transport industry of Hetman Ukraine in 1918-1919 are clarified. the latest examples of legendary monuments of domestic car building should be a priority for the revitalization of the technological heritage of railway transport of Ukraine. Further study of the topic requires clarification of a wide range of issues concerning the impact of these events on the restoration of the Soviet railway industry in the first half of the 1920s. The practical significance of the proposed study can be introduced into the development of the concept of restoration of historical rolling stock for the branch museum collection of Ukrainian railways. Key words: freight car, rolling stock, railways of Ukraine, industry, transport.

The article presents the results of research on the gene expression systems of adaptation of sowing oats from the different ecological and geographical origins at low and high temperatures. Specific cold and heat shock proteins were isolated. Significant peroxidase activity was found in Ivory and Neptune varieties, which characterizes their increased resistance to cold oxidative stress. It was found that the varieties Ivory, Arkan and Neptune are resistant to high temperature and water stress, due to the higher content of heat shock proteins with a molecular weight of 80, 70 and 60 kDa. The content of high-molecular proteins (250 kDa) and proteins with a molecular weight of 110, 100, 80 and 70 kDa has decreased in the Hesser variety, which makes it possible to classify this variety as a low-resistance variety. Higher peroxidase activity was found in Ivory, Arkan and Neptune varieties, which characterizes their increased resistance to oxidative stress in winter and summer It is shown that Ivory and Neptune varieties have high protein expression and are highly frost- and drought-resistant, Arkan and Arthur – moderately frost- and drought-resistant, and Gesser variety has low resistance to stressful environmental conditions, which somewhat limits its use in Ukraine; It is found that the highest peroxidase activity in optimal growing conditions and under the action of water and high temperature stress have varieties Ivory grain purpose and Neptune – fodder purpose, which allows to recommend these varieties for growing in the Forest-Steppe and Steppe of Ukraine.

At nuclear hazard sites, such as the Chernobyl reactor sarcophagus or Fukushima Nuclear Power Plant, radiation is one of the main factors influencing microbial communities including those involved in microbially influenced corrosion (MIC) of metal structures. By studying the impact of radiation on corrosion-relevant bacteria it may be possible in the future to predict changes in MIC. We believe that the composition and function of natural multi-species biofilms will change when exposed to the stress of ionizing radiation. To address this possibility, biofilm formation by Pseudomonas pseudoalcaligenes and Stenotrophomonas maltophilia were studied after exposure to a range of radiation dosages. Altered planktonic cell morphologies and biofilm architectures on submerged glass surfaces were noted 3 – 7 days after low-doasage sub-lethal irradiation (5.3 Gy) of samples at the micro-colony, macro-colony and mature biofilm stages of development. Furthermore, significant differences in the percentage area covered by biofilms and the release of viable planktonic cells was also noted. These observations suggested that exposure, considered as insignificant levels of irradiation, can be enough to alter biofilm formation of corrosion-relevant bacteria. Such low dosage radiation may have significant impact on soil microbial communities in nuclear hazard sites, potentially altering the MIC of exposed metal structures, their stability and service life of underground metal constructions.

The study was aimed to analyze the relation between individual genotypes and allelic variants of SNPs g.2141C>G of growth hormone gene, g.914T>A and g.257A>G of growth hormone receptor gene with growth and reproduction traits and to evaluate the populationgenetic structure in Aberdeen-Angus cattle (Bos taurus L., 1758) sample of Eastern Ukraine according SNPs studied. Allele C of SNP g.2141C>G has a positive correlation with birth weight, body stature, bigger rump, udder and total exterior evaluation score, shorter calving interval and better calve birth weight and negative correlation with calve average daily gain. Allele T of SNP g.914T>A has positive correlation with the muscle and udder size; live weight in each age, average daily gain, weight and average daily gain of calves born conform to the principle AA>TT≥TA. SNP g.257A>G showed a positive correlation for G allele with muscle size. The population is in equilibrium for SNPs g.2141C>G and g.257A>G, and in disequilibrium for SNP g.914T>A. The analysis showed no linkage disequilibrium between SNPs g.914T>A and g.257A>G. Inbreeding coefficient FST in Aberdeen-Angus group studied was 16.1%.

The effect of the static synchronous compensator (STATCOM) on distance protection of a high-voltage transmission line is studied in this article. To carry out the research stated in the topic of the paper, an experimental scheme was developed, equipment was selected, the operation settings of the 3 stages of distance protection were calculated and quad characteristics were built on their basis. All listed above, as well as further experiments, were carried out by the real time digital simulator. The STATCOM model was integrated in the scheme and set next. A series of experiments was carried out: two-phase and three-phase short circuits in various nodes of the scheme with and without the compensator and in various connection nodes. After all the experiments were carried out, appropriate conclusions were made about the impact of FACTS devices on the operation of distance protection. Possible ways to solve detected problems were also proposed.

In the article an experimental power system consisting of Russian equipment, as well as 220 kV power line distance protection, are simulated in the RTDS Simulator. The settings were calculated and the polygonal characteristics of distance protection were constructed. A sequential installation of wind turbines into various nodes of the power system was carried out and the correct operation of the protection was verified. As a result of the study, the impact of wind turbines on the distance protection when they are connected between the protection installation site and the point of the short circuit is revealed. The analysis of this impact is made. Possible ways to solve the identified problems are proposed, such as the use of adaptive distance protection, as well as numerous studies of the behaviour of wind turbines in various operating modes for further analysis and possible adjustment of guidelines for relay protection using new algorithms for calculating and configuring of distance protection. The results of this work can be used to improve and clarify the recommendations for tuning, produced by manufacturers of relay protection devices, which currently do not take into account the impact of wind power generation.

The lack of micronutrients in the diet of the population affects the growth of alimentary-dependent diseases, affects the preservation of health and active longevity. One of the most effective methods of preventing micronutrient insufficiency is the enrichment of mass-consumption food products with vitamin and mineral premixes. Additionally, it is recommended to enrich the missing micronutrients to the level corresponding to the physiological needs of the body with mass-use products, which can include flour confectionery products, in particular cookies. The main factors shaping the quality of finished enriched products are raw materials and production technology. A special role in the application of premixes for flour products is assigned to the mixing process, because when mixing the premix with flour, its uniform distribution must occur throughout the entire volume of the mixture to obtain high-quality finished products with a guaranteed content of vitamins and minerals declared in the premix. Development of recipes and selection of technological parameters of mixing are relevant for the practical implementation of results in industrial production. For this purpose, studies have been conducted to obtain a homogeneous flour mixture consisting of wheat flour and vitamin-mineral premix on a drum mixer. The obtained data allowed us to determine the rational parameters of mixing the initial ingredients, which produce an enriched flour mixture with the specified quality indicators. The numerical values of quality indicators were processed using multiple regression methods, on the basis of which a regression model was obtained describing the quality of a flour-enriched mixture (with a high degree of accuracy) depending on the technological parameters of mixing a drum mixer.

The presented research was aimed to determine the parameters of chlorophyll fluorescence (IChH) curve induction for Vicia sativa L. that were grown on radionuclide contaminated soils by using "Floratest" fluorometer. Plants were inoculated with 5 species of bacteria that might potentially block radionuclide uptake (Agrobacterium radiobacter IМВВ-7246, Azotobacter chroococcum UКМВ-6082, A. chroococcum UКМВ-6003, Bacillus megaterium UКМВ-5724, Rhizobium leguminosarum bv. viceae) and grown in sod-podzolic, сhernozem and peat-bog soils, contaminated with 137Cs (4000±340 Bq/kg). As a result of research, it was determined that the most stressful factors for vetch plants are combination of soil radionuclide and presence of Bacillus megaterium UКМ В-5724, as the number of inactive chlorophyll increased. In addition, the vetch plants significantly increased fixed level of fluorescence (Fst) under the influence of radioactive contamination in presence of Bacillus megaterium UKM B-5724, indicating inhibition of photosynthetic reactions. Other bacteria showed radioprotective properties in almost all types of soil.

The article analyzes the improvement of the quality of enriched cookies to meet the expectations of consumers. This paper shows the application of QFD methodology for a new type of enriched flour confectionery. The analysis allowed to determine the relationship between consumer expectations and technical characteristics of the new product, to prioritize physical and chemical indicators that determine the functional orientation of the product, to identify the most important criteria for consumers. The matrix of consumer requirements, which allows to predict the improvement of the quality of the new product. The results allowed to determine the direction of improving the quality of enriched cookies, to form a range of consumer properties. The results were tested in the production conditions of the enterprise of the Kemerovo region.

Modern electric power systems (EPSs) is a complex, dynamic, non-linear and stiff system. Adequate simulation of processes in EPSs is a non-trivial task. During its solution, in most cases, relay protection (RP) devices are modeled as the simple blocks which are compering input signal with a setting and sending a signal to the commutation equipment. The character and duration of the transients in real EPS due to different disturbances are often depend on the moment of RP tripping and vice versa — occurring transients affecting the operation of RP and automation. This should be reflected in the EPS' model. Ignoring the processes in the RPs devices decreasing the accuracy of the simulations results of the processes in the power systems. This publication presents the results of research carried out using the Hybrid Real-Time Power System Simulator (HRTSim) and supported the identified problems.

This paper proposes the modeling automatic load-frequency control system implemented in the Hybrid real time simulator of electric power system (HRTSim). HRTSim developed for different simulation tasks does not impose any restrictions on the application of mathematical models and allows reproducing spectrum of normal, emergency and post-emergency processes in the electric power systems. The results of experimental studies of steam turbine momentary and sustained fast-valving simulation for transient and steady state stability in the power system confirm the adequacy of simulation tools.

For a correct determining of the overvoltage limiters characteristics, as well as the optimal location of its installation is required to use reliable information about the primary electrical quantities, especially voltage level, in different operation modes of electric power systems (EPS). This problem is highly complex, due to the danger of the experiments in real EPS. Methods and tools for calculation and researches of quasi-stationary and switching overvoltages which are applied to solve this problem not always allow to obtain satisfactory results. The developed tools of comprehensive real-time simulation of electric power systems, providing adequate reproduction of processes associated with overvoltages in EPS, are presented in the article. Fragments of the researches of switching overvoltage in the electrical network of the real power system are given.

The energy losses of a small black hole passing through the Earth are examined. In particular, we investigate the excitations in the frequency range accessible to modern acoustic detectors. The main contribution to the effect is given by the coherent sound radiation of the Cherenkov type., Comment: 6 pages

The leading term of the asymptotic of quasinormal modes in the Schwarzschild background, omega_n = - i n/2, is obtained in two straightforward analytical ways for arbitrary spins. One of these approaches requires almost no calculations. As simply we demonstrate that for any odd integer spin, described by the Teukolsky equation, the first correction to the leading term vanishes. Then, this correction for half-integer spins is obtained in a slightly more intricate way. At last, we derive analytically the general expression for the first correction for all spins, described by the Teukolsky equation., 14 pages, 2 figures; arguments improved, no results changed; 2 references added

Aim. The aim of the study was to analyze effects of SNPs CAPN316 in CAST282 in calpain and calpastatin genes on offspring productive traits produced by dairy and beef bulls. Methods. Data on offspring productivity included milk performance traits (for dairy bulls), birth weight and average daily gain (for beef bulls). Molecular genetic analysis was performed by PCR-RFLP. χ²-, t-tests and Pearson correlation coefficient were used for statistical analysis at significance levels of 0.05. Results. In progeny of dairy bulls number of alleles C in both SNPs demonstrated negative correlation with milk yield (r=-0.577), fat yield (r=-0.794) and protein yield (r =-0.798). G allele of CAPN316 (“wild type”) was associated with increased number of beef bulls progeny. Body weight and average daily gain was better in GG-bulls offspring. Conclusions. C alleles of SNPs CAPN316 in CAST282 being associated with meat quality traits were found to be ineffective in selection for milk production traits. Keywords: calpain and calpastatin genes, SNP, CAPN316, CAST282, bull’s genotype, evaluation on progeny, offspring productivity.